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Anniina Lahti
OULU 2014
D 1257
Anniina Lahti
EPIDEMIOLOGICAL STUDYON TRENDS AND CHARACTERISTICS OF SUICIDE AMONG CHILDREN AND ADOLESCENTS IN FINLAND
UNIVERSITY OF OULU GRADUATE SCHOOL;UNIVERSITY OF OULU, FACULTY OF MEDICINE,INSTITUTE OF CLINICAL MEDICINE, DEPARTMENT OF PSYCHIATRY;OULU UNIVERSITY HOSPITAL, DEPARTMENT OF PSYCHIATRY;HELSINKI UNIVERSITY CENTRAL HOSPITAL,DEPARTMENT OF PSYCHIATRY, DIVISION OF ADOLESCENT PSYCHIATRY
A C T A U N I V E R S I T A T I S O U L U E N S I SD M e d i c a 1 2 5 7
ANNIINA LAHTI
EPIDEMIOLOGICAL STUDY ON TRENDS AND CHARACTERISTICS OF SUICIDE AMONG CHILDREN AND ADOLESCENTS IN FINLAND
Academic Dissertation to be presented with the assentof the Doctoral Training Committee of Health andBiosciences of the University of Oulu for public defencein Auditorium 1, Building PT1 of the Department ofPsychiatry (Peltolantie 17), on 10 October 2014, at 12noon
UNIVERSITY OF OULU, OULU 2014
Copyright © 2014Acta Univ. Oul. D 1257, 2014
Supervised byProfessor Pirkko RäsänenDocent Kaisa RialaDoctor Helinä Hakko
Reviewed byProfessor Eila LaukkanenDocent Markus Henriksson
ISBN 978-952-62-0556-4 (Paperback)ISBN 978-952-62-0557-1 (PDF)
ISSN 0355-3221 (Printed)ISSN 1796-2234 (Online)
Cover DesignRaimo Ahonen
JUVENES PRINTTAMPERE 2014
OpponentProfessor Jouko Lönnqvist
Lahti, Anniina, Epidemiological study on trends and characteristics of suicideamong children and adolescents in Finland.University of Oulu Graduate School; University of Oulu, Faculty of Medicine, Institute ofClinical Medicine, Department of Psychiatry; Oulu University Hospital, Department ofPsychiatry; Helsinki University Central Hospital, Department of Psychiatry, Division ofAdolescent PsychiatryActa Univ. Oul. D 1257, 2014University of Oulu, P.O. Box 8000, FI-90014 University of Oulu, Finland
Abstract
Finnish youth suicide mortality is exceptionally high in international comparisons. This studyinvestigated the epidemiology of child and adolescent (< 18 years) suicides in Finland, with aspecial focus on gender differences.
Two data sets were employed. Data from the national Finnish Cause of Death Register wasused to examine trends in the rates and methods of child and adolescent suicides in Finland in1969–2012. The characteristics of 58 child and adolescent suicides, which occurred in theprovince of Oulu in Northern Finland between 1988 and 2012, were explored based on individual-level data extracted from documents pertaining to establishment of the cause of death inmedicolegal autopsy investigations. The primary source of data was death certificates. Othersources included documents such as police investigation reports and the results of toxicologicalinvestigations. In addition, the suicide data was linked with the Finnish Hospital DischargeRegister.
After 1990, suicide rates generally decreased for males, but increased for females. Amongfemales, hanging exceeded poisoning as the most common suicide method after 1990, whereasfirearms were the most common method among males, until traffic suicides took the leadingposition for both genders during 2008–2012. Violent suicide methods of all types increased amongfemales after 1990. Male firearm suicide rates were nearly three times higher in Northern Finlandthan in Southern Finland, while there was no regional difference in rates of suicide by othermethods.
15% of male and 17% of female suicide victims in the province of Oulu had a history ofprevious psychiatric hospitalization. The discharge diagnoses were heterogeneous. Previoussuicidality and self-cutting were more common among females than males. Half of all adolescentswere under the influence of alcohol at the time of their death. The majority of the intoxicatedadolescents committed suicide at night, during descending blood alcohol concentrations. Anotable fall peak was observed in male firearm suicides.
The increase in violent, i.e. more lethal, suicide methods among females is alarming, asfemales are known to have high rates of attempted suicide. The special characteristics of malefirearm suicides in Northern Finland suggest the need for region-specific preventive measures.The high frequency of acute alcohol use in child and adolescent suicides warrants attention.
Keywords: adolescent, alcohol, epidemiologic studies, firearms, gender, mentaldisorders, seasonality, suicide
Lahti, Anniina, Epidemiologinen tutkimus lasten ja nuorten itsemurhienerityispiirteistä Suomessa. Oulun yliopiston tutkijakoulu; Oulun yliopisto, Lääketieteellinen tiedekunta, Kliinisenlääketieteen laitos, Psykiatria; Oulun yliopistollinen sairaala, Psykiatrian klinikka; HYKS,Psykiatrian tulosyksikkö, Nuorisopsykiatrian klinikkaryhmäActa Univ. Oul. D 1257, 2014Oulun yliopisto, PL 8000, 90014 Oulun yliopisto
Tiivistelmä
Suomalaisnuorten itsemurhakuolleisuus on kansainvälisessä vertailussa korkea. Tässä epidemio-logisessa tutkimuksessa selvitettiin alle 18-vuotiaiden suomalaislasten ja -nuorten itsemurhienerityispiirteitä.
Tutkimuksessa käytettiin kahta aineistoa. Kansallisen kuolemansyyrekisterin avulla selvitet-tiin alaikäisten itsemurhakuolleisuutta ja itsemurhien tekotapojen muutoksia Suomessa vuosina1969–2012. Empiirisen aineiston asiakirjat koskivat entisen Oulun läänin alueella vuosina1988–2012 itsemurhan tehneiden 58 alaikäisen oikeuslääketieteellistä kuolemansyyn selvittä-mistä. Aineiston perustiedot koottiin kuolintodistuksista. Lisäksi tietoja poimittiin muista kuole-mansyyn selvittämisasiakirjoista, kuten poliisin tutkintapöytäkirjoista ja oikeuskemiallisista tut-kimustuloksista. Aineistoon liitettiin myös hoitoilmoitusrekisteritietoja.
1990-luvun alusta lähtien poikien itsemurhat ovat vähentyneet ja tyttöjen lisääntyneet. Tytöil-lä hirttäytyminen ohitti myrkyttäytymisen yleisimpänä itsemurhan tekotapana vuoden 1990 jäl-keen. Pojilla ampuminen oli yleisin itsemurhamenetelmä koko tutkimusjakson ajan, kunnes lii-kenneitsemurhat nousivat yleisimmäksi tekotavaksi molemmilla sukupuolilla vuosina2008–2012. Väkivaltaisten itsemurhan tekotapojen käyttö on lisääntynyt tytöillä vuodesta 1990lähtien. Poikien ampumisitsemurhakuolleisuus oli Pohjois-Suomessa lähes kolminkertainenmuuhun Suomeen verrattuna. Vastaavaa alueellista eroa ei ollut muissa tekotavoissa.
Oulun läänin alueella itsemurhan tehneistä pojista 15 % ja tytöistä 17 % oli ollut psykiatri-sessa osastohoidossa ennen itsemurhaa. Diagnoosit olivat heterogeenisiä. Aiempi itsetuhoisuusja viiltely oli yleisempää tytöillä kuin pojilla. Puolet alaikäisistä oli ollut humalassa itsemurha-hetkellä. Suurin osa päihtyneenä tehdyistä itsemurhista tapahtui laskuhumalassa yöaikaan. Poiki-en ampumisitsemurhat olivat yleisempiä syksyllä kuin muina vuodenaikoina.
Väkivaltaisten eli tappavampien itsemurhamenetelmien lisääntyminen tytöillä on huolestutta-vaa, koska tyttöjen itsemurhayritysten tiedetään olevan yleisiä. Itsemurhien ehkäisyssä tulisihuomioida alueelliset erityispiirteet, joita tässä tutkimuksessa havaittiin poikien ampumisitse-murhissa Pohjois-Suomessa. Päihtyneenä tehtyjen itsemurhien suuri osuus alaikäisillä korostaanuorten alkoholinkäytön vähentämisen merkitystä.
Asiasanat: alkoholi, aseet, epidemiologiset tutkimukset, itsemurha,mielenterveyshäiriöt, nuoret, sukupuoli, vuodenaikaisvaihtelu
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Acknowledgements
This work was carried out at the Department of Psychiatry of the University of
Oulu and the Department of Psychiatry of Oulu University Hospital. I wish to
express my gratitude to Professor (emeritus) Matti Isohanni, Professor Juha
Veijola and Docent Outi Saarento for providing excellent facilities in which to
work and for their support during my work.
I am most grateful to my supervisors Professor Pirkko Räsänen, Docent Kaisa
Riala and Dr Helinä Hakko. I feel privileged to have been tutored and inspired by
this brilliant trio. Pirkko, I especially value your intelligence, inventiveness and
optimistic outlook. Kaisa, I always looked forward to the special monthly “Kaisa
days” when you visited Oulu and I had the opportunity to hear your clinical
viewpoints and enjoy your sense of proportion. Helinä, I truly appreciate your
helpfulness, patience and wisdom, and of course your expertise in statistics.
I would like to sincerely thank all of my co-authors for their valuable
contribution to the original publications. Professor (emeritus) Erkki Vuori is
gratefully acknowledged for sharing his expertise in forensic toxicology. In
addition, I would like to acknowledge the Department of Forensic Medicine of
the University of Oulu and, for their more recent contribution, the National
Institute for Health and Welfare for their kind collaboration in providing the study
data.
I greatly appreciate the pre-examiners of this thesis, Professor Eila
Laukkanen and Docent Markus Henriksson, for their advice and constructive
comments. The professional language experts are warmly thanked for revising the
English language of the original publications and the final form of this thesis.
M.A. Olli Romppanen is acknowledged for his technical assistance with the
thesis.
I owe my thanks to Ms. Pirkko Kaan, Ms. Niina Keränen, Ms. Anja
Kylmänen, Mr. Jani Moisala and other staff at the Department of Psychiatry of
Oulu University Hospital and the Department of Psychiatry of the University of
Oulu for their help during the work. The Research & Development Unit (TUKE)
is acknowledged for its financial and practical support for this study.
I wish to express my loving thanks to all of my friends for just being there
and for encouraging me throughout the years. Finally, I reserve my deepest
gratitude for all of my family: my parents and siblings and their families. I cannot
thank you enough for all the support and unconditional love you have given me
throughout my life.
8
Financial support received for this work from the Department of Psychiatry
of Oulu University Hospital, The Alma and K. A. Snellman Foundation, The Emil
Aaltonen Foundation, The Finnish Cultural Foundation, The Finnish Medical
Foundation, The Finnish Psychiatric Research Foundation, The Jalmari and
Rauha Ahokas Foundation, The Otto A. Malm Foundation, The Päivikki and
Sakari Sohlberg Foundation, and The Yrjö Jahnsson Foundation is gratefully
acknowledged.
Oulu, August 2014 Anniina Lahti
9
Abbreviations
APC Annual percent change
BAC Blood alcohol concentration
BMI Body mass index
CI Confidence interval
FHDR Finnish Hospital Discharge Register
ICD-8 International Statistical Classification of Diseases, Injuries and
Causes of Death, 8th edition
ICD-9 International Statistical Classification of Diseases, Injuries and
Causes of Death, 9th edition
ICD-10 International Statistical Classification of Diseases, Injuries and
Causes of Death, 10th edition
SD Standard deviation
UAC Urine alcohol concentration
WHO World Health Organization
10
11
List of original publications
This thesis is based on the following publications, which are referred throughout
the text by their Roman numerals:
I Lahti A, Räsänen P, Riala K, Keränen S & Hakko H (2011) Youth suicide trends in Finland, 1969–2008. Journal of Child Psychology and Psychiatry 52: 984–991.
II Lahti A, Keränen S, Hakko H, Riala K & Räsänen P (2014) Northern excess in adolescent male firearm suicides: A register-based regional study from Finland, 1972–2009. European Child & Adolescent Psychiatry 23: 45–52.
III Lahti A, Harju A, Hakko H, Riala K & Räsänen P (2014) Suicide in children and young adolescents: A 25-year database on suicides from Northern Finland. Journal of Psychiatric Research 58: 123–128.
IV Lahti A, Räsänen P, Karvonen K, Särkioja T, Meyer-Rochow VB & Hakko H (2006) Autumn peak in shooting suicides of children and adolescents from Northern Finland. Neuropsychobiology 54: 140–146.
Some unpublished data are also presented in this thesis.
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13
Contents
Abstract
Tiivistelmä
Acknowledgements 7
Abbreviations 9
List of original publications 11
Contents 13
1 Introduction 15
2 Review of the literature 17
2.1 Terms and definitions .............................................................................. 17
2.1.1 Suicide .......................................................................................... 17
2.1.2 Suicidal and nonsuicidal self-injury, self-harm and
suicidality ..................................................................................... 18
2.1.3 Childhood and adolescence .......................................................... 19
2.2 Suicide research methodology ................................................................ 20
2.2.1 Macro approach ............................................................................ 21
2.2.2 Micro approach ............................................................................. 21
2.3 Epidemiology of child and adolescent suicides ...................................... 22
2.3.1 General characteristics .................................................................. 22
2.3.2 Suicide rates and secular trends .................................................... 23
2.3.3 Methods of suicide ....................................................................... 25
2.4 Risk factors for child and adolescent suicides ........................................ 25
2.4.1 Mental disorders, substance abuse and alcohol
intoxication ................................................................................... 26
2.4.2 Previous suicide attempt and self-harm ........................................ 29
2.4.3 Familial and psychosocial risk factors .......................................... 29
2.4.4 Availability of lethal methods ....................................................... 30
2.4.5 Suicide contagion and clusters ..................................................... 31
2.5 Seasonal and other temporal patterns of suicide ..................................... 31
2.6 Child and adolescent suicide prevention ................................................. 32
2.6.1 Universal suicide prevention ........................................................ 33
2.6.2 Selected suicide prevention .......................................................... 35
2.6.3 Indicated suicide prevention ......................................................... 36
3 Aims of the study 39
14
4 Material and methods 41
4.1 Suicide data ............................................................................................. 41
4.1.1 Macro approach (I, II) .................................................................. 41
4.1.2 Micro approach (III, IV) ............................................................... 45
4.2 Statistical methods .................................................................................. 49
4.3 Ethical considerations and personal involvement ................................... 51
5 Results 53
5.1 Macro approach (I, II) ............................................................................. 53
5.1.1 Child and adolescent suicide trends in Finland (I) ....................... 53
5.1.2 Child and adolescent male firearm suicides (II) ........................... 55
5.2 Micro approach (III, IV).......................................................................... 56
5.2.1 Demographic features of child and adolescent suicides
(III) ............................................................................................... 56
5.2.2 Suicide methods (III) .................................................................... 57
5.2.3 Mental health (III) ........................................................................ 57
5.2.4 Circumstances of the suicides (III, IV) ......................................... 60
5.2.5 Toxicology findings (III) .............................................................. 63
5.2.6 Somatic findings from the medicolegal autopsies (III) ................ 66
6 Discussion 67
6.1 Overview of the results ........................................................................... 67
6.2 Discussion of the findings ....................................................................... 68
6.2.1 Trends in child and adolescent suicides (I) ................................... 68
6.2.2 Regional differences in child and adolescent male firearm
suicides (II) ................................................................................... 70
6.2.3 Characteristics of child and adolescent suicides in the
province of Oulu (III, IV) ............................................................. 72
6.3 Strengths and limitations ......................................................................... 76
6.3.1 Strengths of the study ................................................................... 76
6.3.2 Limitations of the study ................................................................ 77
7 Conclusions 79
7.1 Main conclusions .................................................................................... 79
7.2 Implications of the study ......................................................................... 80
7.3 Implications for further research ............................................................. 81
References 83
Appendix 97
Original publications 99
15
1 Introduction
Suicide in a child or adolescent is a painful and devastating event that has a
widespread effect on families, friends, and the community. To many, the very idea
of young people dying by their own hands is incomprehensible. Yet, it is
estimated that global annual suicide fatalities among children and adolescents
may approach 100,000 (Greydanus & Calles 2007), making suicide one of the
major causes of adolescent mortality throughout the world (Patton et al. 2009).
Suicidal behavior in the young population has long been recognized as a
serious public health issue. Completed suicide in children and adolescents is the
tip of the iceberg considering the large continuum of suicidality. According to
some estimates, there are more than 100 suicide attempts to every completed
suicide among adolescents (Maris 2002). Approximately 2–10% of adolescents
report having attempted suicide, females more often than males (Bridge et al. 2006, Evans et al. 2005). Thoughts about death and suicide are common in
adolescence. Around 10% to 30% of adolescents have had suicidal thoughts at
some point in their lives (Evans et al. 2005, Nock et al. 2013).
Finnish adolescent suicide mortality is among the highest in Europe
(European Detailed Mortality Database 2014). In early 21st century Finland,
suicide has been the second leading cause of death among 15–19-year-old
adolescent males and the third for females of the same age (Statistics Finland
2014a). The United Nations Committee on the Rights of the Child has recently
expressed its concern about the high rate of depression and high number of
suicides among children in Finland, and about inadequate access to mental health
services (United Nations Committee on the Rights of the Child 2011). The
committee recommended the strengthening of mental health services for children
and the intensification of suicide prevention measures.
Gender is an important factor in child and adolescent suicides. Whereas the
rate of attempted suicides is higher among females, males predominate in
completed suicides, particularly in Western societies (Hawton et al. 2012b).
Further, specific psychiatric disorders, a history of previous suicidality, and the
distribution of different suicide methods among adolescent suicide victims have
all been shown to vary by gender (Brent et al. 1999, Grøholt et al. 1999,
Marttunen 1994, Shaffer et al. 1996). Despite the clinical importance of these
differences, not all child and adolescent suicide studies have reported their
findings for males and females separately, which may reduce the utilizability of
the results.
16
The ultimate aim of suicide research is to increase our knowledge of suicidal
behaviors in order to form a basis for effective preventive measures.
Epidemiological studies have an important contribution to make to the field of
suicidology, as they provide insights regarding the different determinants of
suicide. Accordingly, this study sought to investigate the epidemiology of child
and adolescent suicides in Finland, with a special focus on gender differences.
Finland’s reliable national registers and cause-of-death certification practices
form a good basis for performing such research.
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2 Review of the literature
2.1 Terms and definitions
2.1.1 Suicide
The concept of suicide is much more complex than is conveyed by the words
“killing oneself”, which originate in the Latin terms “sui” (of oneself) and
“caedere” (to kill). In defining suicide, it has been emphasized that suicide is a
behavior – not a disease, disorder or diagnosis – and that all behavior is
multidimensional and determined by multiple factors (Silverman et al. 2007).
Numerous definitions of suicide have been proposed, a selection of which is
presented in Table 1.
Table 1. A selection of definitions of suicide.
Definition of suicide Source
The act of killing oneself deliberately initiated and performed by the person
concerned in the full knowledge, or expectation, of its fatal outcome.
World Health
Organization 1998
Self-inflicted death with evidence (either explicit or implicit) that the person
intended to die.
American Psychiatric
Association 2003
An act with a fatal outcome, which the deceased, knowing or expecting a
potentially fatal outcome, has initiated and carried out with the purpose of
bringing about wanted changes.
De Leo et al. 2006
Self-injurious behavior that resulted in a fatality and was associated with
at least some intent to die as a result of the act.
Posner et al. 2007
Death caused by self-directed injurious behavior with any intent to die
as a result of the behavior.
Crosby et al. 2011
Death, i.e. a fatal outcome, is the most easily agreed element between different
definitions. Other key aspects include the agency of the act (self-inflicted), the
intention to die or stop living, and consciousness/awareness of the outcome (De
Leo et al. 2006, Silverman 2006). With regard to the intention to die, because of
the generally ambivalent attitude towards living or dying in the case of an
individual contemplating suicide, post mortem determination of the presence and
degree of suicidal intent is often difficult (Silverman 2006). A central question
posed by De Leo et al. (2006) is, “how much more must the suicidal subject wish
for death rather than life, in order for their death to be classified as a suicide”.
Establishing intent and consciousness/awareness of the outcome can be
18
particularly problematic regarding suicide in children and young adolescents.
According to Mishara (1999), coroners and medical examiners may not classify a
pediatric death as suicide due to the commonly held view that children have an
insufficient understanding of the finality and irreversibility of death. However,
Mishara (1999) found that most 5–7-year-olds and almost all children aged 8–12
know that suicide results in death and understand that death is permanent and
final.
For the purposes of this thesis, suicide is defined as deaths that have been
officially classified as suicides by medical examiners, based on a medicolegal
death investigation practice.
2.1.2 Suicidal and nonsuicidal self-injury, self-harm and suicidality
Not only the concept of suicide itself, but the overall terminology, nomenclature
and classification systems of suicidology are complex and have been a topic of
considerable international debate (De Leo et al. 2006, Skegg 2005). From one
viewpoint, death is not always the aim of self-injurious behaviors, i.e. there is no
intent to die. The presence or absence of the intent to die can therefore be used as
a premise for dichotomizing self-injurious behaviors into suicidal (when there is
evidence of suicidal intent) and nonsuicidal (no evidence of suicidal intent)
behavior (Crosby et al. 2011, Kapur et al. 2013). On the other hand, “self-harm”
is a term used to encompass all self-injurious behaviors regardless of suicidal
intent (Hawton et al. 2012b, Skegg 2005). The reasoning behind the latter view is
that suicidal intent is fluid, it exists on a continuum rather than being a categorical
construct, and its evaluation is difficult and unreliable (Brunner et al. 2014,
Ougrin 2012). Furthermore, multiple motivations for self-harm may exist
simultaneously, and even the persons themselves may be equivocal as to the
underlying reasons of their self-harming behavior (Kapur et al. 2013).
The term “suicidality” is a broad concept that refers to all suicide-related
thoughts and behaviors, including suicidal ideation, suicide attempts and
completed suicides (Bridge et al. 2006). Suicidal ideation has been defined as
thoughts about suicide that may include the planning of suicide attempts
(Waldvogel et al. 2008), a wish to or threat to die (Pelkonen & Marttunen 2003),
or thoughts of harming or killing oneself (Bridge et al. 2006). According to a
definition provided by Crosby et al. (2011), a suicide attempt is a non-fatal self-
directed potentially injurious behavior, with any intent to die as a result of such
behavior. However, in common language “suicide attempt” is often used as an
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umbrella term for any self-injurious behaviors regardless of intent, a view also
shared by some investigators (Kerkhof 2000).
Differences of opinion also exist as to the term “nonsuicidal self-injury”
(NSSI), defined as intentional self-inflicted damage to the surface of the body
without conscious suicidal intent (American Psychiatric Association 2013). Here,
the focus of controversy again rests on the question of whether a clear-cut
distinction can be made between “non-suicidal” and “suicidal” self-injury –
especially given the strong association that exists between NSSI and suicidal
behavior (Kapur et al. 2013). Nevertheless, it is of importance in terms of this
thesis that the most common method of NSSI is cutting or carving oneself with a
sharp implement (Nock 2010). In the research literature, “self-mutilation” and
“self-cutting” are some of the terms used to refer to such behavior (although often
with no precise definition regarding the suicidal intent of the individual). In this
thesis, the term “self-cutting” will be used to describe the above-mentioned
behavior, regardless of the suicidal intent.
2.1.3 Childhood and adolescence
One dictionary definition of childhood refers to it as the period of life before
puberty (HarperCollins 2014). In the Convention on the Rights of the Child,
children are defined as persons up to the age of eighteen years (United Nations
1989). In legal terms, children are referred to as those under the age of majority,
the limit for which is 18 years in many countries, including Finland. The World
Health Organization (WHO) defines adolescence as the period in human growth
and development that occurs after childhood and before adulthood, from the ages
of 10 to 19 years (World Health Organization 1986). Some other definitions of
adolescence are not based solely on chronological age. For example, it has been
stated that adolescence begins with the onset of physiologically normal puberty,
and ends when an adult identity and behavior are accepted (Sacks et al. 2003).
As a consequence of the various definitions of childhood and adolescence,
studies of child and adolescent suicides tend to be marked by high variability in
age groupings. Numerous suicide research papers focus on “young people”
(individuals aged 15–24 years), thereby including adolescents in this broader age
group and excluding children and younger adolescents. Since the developmental
and sociodemographic characteristics of children and adolescents are in many
ways different from those of young adults, the main emphasis of this literature
20
review is on studies investigating suicides in children and adolescents under 20
years of age.
In this thesis, children and adolescents are defined as those under 18 years of
age. In addition to being the age of majority, this age limit is of importance in
child and adolescent mental health services and social services in Finland. The
Finnish Child Welfare Act (2007) refers to children as anyone under 18 years of
age. The Finnish Mental Health Act (1990) requires that patients under 18 years
of age – referred to as “minors” – in need of inpatient psychiatric treatment must
be treated separately from adults. Further, regarding involuntary commitment, the
conditions for ordering treatment are broader for minors than for adults (Mental
Health Act 1990). It is also worth noting that the Finnish law defines the time
limits within which patients must be given access to health care services, and
regarding access to mental health care the treatment of children and young people
(<23 years of age) must begin within three months, while the limit is six months
for adults (Health Care Act 2010).
2.2 Suicide research methodology
Suicide is a complex research subject. By definition, the first obstacle concerns
the unavailability of the people who it is most important to understand – the
deceased themselves (Berman et al. 2006). Another challenge is the relative rarity
(low base rate) of completed suicide amongst the population. This means that in
prospective studies, the generally preferred research strategy, very large sample
sizes would be required in order to obtain meaningful results (Nock 2009, Robins
& Kulbok 1986). In addition to clinical and methodological difficulties, potential
ethical restraints are of importance (Berman et al. 2006). It is therefore not
surprising that studies of adolescent suicidality have to a great extent focused on
living suicidal individuals, such as suicide attempters and individuals with a
history of self-harm. However, although adolescent suicide attempters and
completers share many characteristics, they also differ from each other in many
important ways (Moskos et al. 2004). Results obtained from studies on the former
group may not therefore directly apply to the latter.
As outlined by Berman et al. (2006), there are two main methodological
strategies for studying completed suicides. The “macro approach” makes use of
large samples of aggregate data to study the characteristics of population groups.
The “micro approach”, on the other hand, investigates individual suicide cases
with the aim of identifying more specific clinical characteristics and risk
21
variables. In both approaches, suicide data may be linked to various registers,
such as national health registers, in order to obtain additional relevant
information.
2.2.1 Macro approach
The macro approach, i.e. the ecological research method, is based on population
data rather than focusing on the characteristics of individual suicides (Stack
1987). Suicide counts and rates are compared between regions, genders, or age
groups, for example. Temporal trends in the suicide mortality of different
populations can also be examined. (Robins & Kulbok 1986)
2.2.2 Micro approach
In the micro approach, i.e. case study strategy, individuals serve as units of
analysis (Stack 1987). Sources of data include existing records, and/or interview
data (of relatives, physicians, etc.) generated for research purposes. Compared
with the macro approach, case studies involve the prospect of finding more
specific predictors for suicide. (Berman et al. 2006) Two main types of micro
approach strategies, i.e. psychological autopsies and record review studies,
account for most of our current knowledge of the clinical characteristics and risk
factors of adolescent suicides.
Psychological autopsies
In psychological autopsy studies, interviews of family members, other close
intimates and health professionals are used in conjunction with different kinds of
record data to reconstruct the social and psychological features of deaths by
suicide (Marttunen et al. 1993). This technique has been regarded as particularly
useful when studying suicides among young people, because many informants,
such as parents and other family members, friends, and teachers, are available in
most cases (Marttunen et al. 1993). Nevertheless, there are surprisingly few
psychological autopsy studies on child and adolescent suicides. Since the 1980s,
only around ten research groups have published results of psychological autopsies
conducted on children and adolescents under 20 years of age (Brent et al. 1999,
Eisele et al. 1987, Freuchen et al. 2012, Marttunen et al. 1991, Portzky et al. 2009, Renaud et al. 2008, Rich et al. 1990, Shaffer et al. 1996, Shafii et al. 1985).
22
Record review studies
Record review (case series) studies make use of the available record data. Such
information is typically extracted from suicide case files compiled by medical
examiners or other relevant authorities responsible for establishing the cause of
death. Case files usually include death certificates in combination with
investigatory records containing more detailed information (Berman et al. 2006).
2.3 Epidemiology of child and adolescent suicides
2.3.1 General characteristics
There is a great deal of international variability in adolescent suicide rates
(Wasserman et al. 2005). A universal characteristic of suicide epidemiology,
however, is the rarity of completed suicide before puberty and the subsequent
increase in frequency throughout adolescence (Gould et al. 2003). Explanations
proffered for the low rates of suicide in children and young adolescents as
compared to older adolescents include fewer risk factors, lower suicide intent and
cognitive immaturity in the planning and execution of a lethal act (Brent et al. 1999, Grøholt et al. 1998).
The male-female disparity in rates of completed suicides is another almost
universal pattern in adolescent suicide epidemiology, with higher rates among
adolescent males than females being identified throughout Western countries
(Wasserman et al. 2005). In contrast, rates of self-harm, suicide attempts, suicidal
ideation and self-cutting are generally more common among female than male
adolescents (Brunner et al. 2014, Laukkanen et al. 2009, Lewinsohn et al. 1996,
Lewinsohn et al. 2001, Moran et al. 2012, Wunderlich et al. 2001). This
discrepancy between males and females has been called the “gender paradox of
suicidal behavior” (Canetto & Sakinofsky 1998, Schrijvers et al. 2012). The
reasons for the phenomenon are by no means clear. Suggested explanations
include gender differences in accuracy and honesty in the reporting of suicidal
behavior (Canetto & Sakinofsky 1998, Lewinsohn et al. 2001), the influence of
cultural factors (suicide being regarded as a masculine and attempting suicide as
feminine behavior) (Canetto 1997), disparity in help-seeking behaviors (Beautrais
2002) and differences in methods of suicide (Beautrais 2003) and
psychopathology (Kaess et al. 2011, Schrijvers et al. 2012).
23
2.3.2 Suicide rates and secular trends
The age groupings most commonly utilized when reporting rates of child and
adolescent suicides are those of 10–14 years and 15–19 years, which is likely due
to the statistical practices of the World Health Organization. As regards the
younger group, worldwide suicide rates (per 100,000 population) among 10–14-
year-olds range between 0.0 and 8.5 for males and between 0.0 and 6.5 for
females (Dervic et al. 2008, Kolves & De Leo 2014). Recent reports on secular
trends in suicide rates in this age group are scarce, and where published data
exists, the findings are inconsistent. Decreasing suicide trends in 10–14-year-old
males in Austria between 1970–2001 (Dervic et al. 2006) and a sporadic increase
among females in Canada from the 1980s until 2008 (Skinner & McFaull 2012)
have been reported. At the same time, no significant changes in suicide rates
occurred among Austrian females (Dervic et al. 2006), Canadian males (Skinner
& McFaull 2012), or among either gender in England and Wales in the first
decade of the 21st century (Windfuhr et al. 2013).
Table 2 presents the rates of suicide (per 100,000 population) among 15–19-
year-old adolescents by gender in selected European countries. Eastern European
countries, Finland and Ireland lead the rates among male adolescents, and the
situation is largely similar among females.
24
Table 2. Suicide death rate (per 100,000 population) among 15–19-year-old males and
females in selected European countries. (European Detailed Mortality Database 2014)
Males Females
Country and year 1 Suicide death rate Country and year 1 Suicide death rate
Russian Federation 2010 24.7 Russian Federation 2010 7.2
Belarus 2009 21.3 Lithuania 2010 6.2
Lithuania 2010 20.2 Belarus 2009 6.1
Finland 2011 20.2 Norway 2012 5.7
Ukraine 2012 18.1 Finland 2011 5.6
Ireland 2010 17.6 Austria 2011 4.6
Latvia 2012 14.8 Ukraine 2012 4.0
Poland 2011 13.4 Sweden 2010 3.9
Czech Republic 2012 10.4 Belgium 2010 3.8
Sweden 2010 9.6 Ireland 2010 3.7
Estonia 2012 8.8 Switzerland 2010 3.6
Hungary 2012 8.4 Netherlands 2011 2.9
Belgium 2010 8.4 Poland 2011 2.4
Iceland 2009 8.2 Denmark 2011 2.3
Norway 2012 7.7 France 2010 2.3
France 2010 7.2 Germany 2012 2.3
Austria 2011 7.1 United Kingdom 2010 2.1
Switzerland 2010 6.9 Greece 2011 1.8
Germany 2012 6.6 Hungary 2012 1.8
Netherlands 2011 5.1 Czech Republic 2012 1.6
Denmark 2011 4.9 Portugal 2011 1.5
United Kingdom 2010 4.4 Spain 2011 1.1
Spain 2011 2.9 Italy 2010 0.8
Italy 2010 2.8 Estonia 2012 0.0
Greece 2011 2.1 Iceland 2009 0.0
Portugal 2011 1.4 Latvia 2012 0.0 1 Latest year available.
With regard to changes over time, an upward trend in suicides among males aged
15–19 years was reported in many countries between the 1960s and 1990s (Rutz
& Wasserman 2004, Wasserman et al. 2005). More recently, declining trends in
male adolescent suicides have been reported in the United States (US) (Bridge et al. 2008), Canada (Skinner & McFaull 2012) and the United Kingdom (UK)
(Windfuhr et al. 2008, Windfuhr et al. 2013), for example. Opposing trends have
also emerged, for example in South Korea (Park et al. 2014). Among 15–19-year-
old females, suicide rates have generally remained more stable in many countries
(Madge 1999, Rutz & Wasserman 2004, Wasserman et al. 2005). In recent times,
25
it has been reported that adolescent female suicide rates are stable in the UK
(Windfuhr et al. 2013), and decreasing in the US (Bridge et al. 2008), but are
increasing in Canada (Skinner & McFaull 2012). To conclude, secular trends in
adolescent suicides have been diverse between different countries and genders.
2.3.3 Methods of suicide
As well as suicide rates and trends, the distribution of suicide methods among
adolescents varies between nations and genders. Use of firearms is the leading
method of suicide among 15–19-year-old males in Finland (Statistics Finland
2014a) and the US (Lubell et al. 2007), as well as in Switzerland for all <20-year-
old males (Hepp et al. 2012). Firearms have also been the most common suicide
method among 15–19-year-old males in Canada, but hanging surpassed firearms
at the beginning of the 1990s (Skinner & McFaull 2012). At the same time, in
Canada the distribution of suicide methods also changed among adolescent
females, with hanging overtaking poisoning as the leading method of suicide
(Skinner & McFaull 2012). In a similar manner, in the US at the beginning of the
2000s hanging surpassed firearms as the most common suicide method among
adolescent females (Lubell et al. 2007).
In contrast to the use of firearms among adolescent males, hanging is the
most common method of suicide among 15–19-year-old females in Finland
(Statistics Finland 2014a), while traffic (railway suicides) is the most common
method among Swiss female adolescents (Hepp et al. 2012). In Italy, hanging is
the leading method among males, whereas jumping from a high place accounts
for most female adolescent suicides (Pompili et al. 2009). Otherwise, recent
reports on the distribution of suicide methods among European adolescents (<20
years) are scarce. However, a study of 15 European countries examined suicide
rates in young people (15–24 years) and found that hanging was the most
common method of suicide among males in 12 countries and among females in
all but one country (Värnik et al. 2009).
2.4 Risk factors for child and adolescent suicides
Suicide is a highly complex and multidetermined outcome. No single cause can
be shown to underlie any individual suicide, and no single path leads to this end.
Nevertheless, research from several previous decades has consistently identified
26
factors that are associated with an increased likelihood of completed suicide in
adolescence – that is, risk factors for adolescent suicides.
2.4.1 Mental disorders, substance abuse and alcohol intoxication
Psychological autopsy studies have identified at least one psychiatric disorder in
approximately 90% of adolescent suicide victims (Brent et al. 1993b, Marttunen
et al. 1991, Portzky et al. 2005, Renaud et al. 2008, Shaffer et al. 1996).
However, Brent et al. (1999) found that only 60% of under 16-year-old suicide
victims had a diagnosable psychiatric disorder, and similar results have also been
found in other studies (Grøholt et al. 1998, Shaffer et al. 1996).
In psychological autopsy studies, mood disorder has been the most prevalent
mental disorder among adolescent suicide victims (Brent et al. 1993b, Grøholt et al. 1999, Renaud et al. 2008, Shaffer et al. 1996, Shafii et al. 1988). Gender
difference is a consistent finding across studies: more female (approximately
70%) than male (approximately 40–60%) adolescent suicide victims have
suffered from a mood disorder (Brent et al. 1999, Marttunen et al. 1991, Shaffer
et al. 1996). Substance abuse or dependence (alcohol or drugs) is another
important risk factor (Brent et al. 1999, Marttunen et al. 1991, Portzky et al. 2005, Renaud et al. 2008, Shaffer et al. 1996). As regards gender differences, one
study from the US (Shaffer et al. 1996) found higher rates of substance abuse
among male adolescents (42% in males vs. 12% in females), whereas another
(Brent et al. 1999) reported fairly similar rates (35% vs. 24%) between genders.
In a Finnish study (Marttunen et al. 1991), the rates of alcohol abuse/dependence
were higher among females (23% vs. 44%), although note should be taken of the
small number of adolescent females (n=9) in that study. Findings regarding age
differences in terms of the prevalence of substance abuse among adolescent
suicide victims are more consistent, the rates being significantly higher among
older adolescents (Brent et al. 1999, Grøholt et al. 1998, Shaffer et al. 1996).
Substance abuse is often comorbid with mood disorders (Brent et al. 1993b,
Shaffer et al. 1996), and psychiatric comorbidity is common in adolescent
suicides in general, as up to 70% of adolescent suicide victims have had more
than one psychiatric disorder (Bridge et al. 2006). Apart from mood disorders and
substance abuse, disruptive disorders (such as oppositional disorder) are among
the mental disorders that have been shown to increase the risk of adolescent
suicide, especially among males (Brent et al. 1999, Renaud et al. 2008, Shaffer et al. 1996).
27
Whereas alcohol abuse, i.e. chronic alcohol use has consistently been shown
to be a risk factor in adolescent suicide, empirical research on the role of acute
alcohol use in increasing the risk of suicide among adolescents is scarce. On a
general level, it has been suggested that acute alcohol consumption is a potent risk
factor for completed suicides (Lamis & Malone 2012). Proposed mechanisms
include increased psychological distress (particularly, it is suggested, during
descending blood alcohol concentration, which is often associated with depressed
and sedative-like effects (Holdstock & de Wit 1998)), increased aggressiveness,
and the impairment of cognitive processes (Hufford 2001). In relation to cognitive
functioning, Hufford (2001) argues that alcohol use impedes alternative coping
strategies and narrows the range of options that the individual perceives as being
available. It is also well-known that alcohol impairs inhibitory control (Field et al. 2010) and that there is a strong association between impulsivity and alcohol use
(Lamis & Malone 2012).
Table 3 presents results from previous studies that included data, based on the
results of forensic toxicology examinations, on adolescent suicide victims who
were under the influence of alcohol at the time of their death. Where information
is available, the results are shown by gender. The overall figures for acute alcohol
use among adolescent suicide victims fall between 10% and 50%, between 20%
and 50% for males and between 10% and 40% for females, although an
exceptionally high proportion (56%) of intoxicated female adolescent suicide
victims was reported in a Finnish study by Marttunen et al. (1992). In addition to
the information provided in Table 3, a study from Belgium (Portzky et al. 2005)
reported that 37% of adolescent suicide victims were known, based on informant
interviews, to have consumed alcohol during the day of their death (no results of
toxicology examinations were available). Regarding age differences, studies have
shown that being under the influence of alcohol at the time of death is rare among
<15-year-old adolescents (Brent et al. 1999, Freuchen et al. 2012, Grøholt et al. 1998).
28
Ta
ble
3. A
do
les
cen
t v
icti
ms
un
de
r th
e in
flu
en
ce o
f a
lco
ho
l a
t th
e t
ime
of
de
ath
, b
ase
d o
n f
ore
ns
ic t
ox
ico
log
y e
xam
inati
on
s.
Stu
dy
Countr
y, t
ime s
pa
n
Ag
e g
rou
p
(ye
ars
)
To
tal n
(m
ale
s %
) A
lcohol t
oxi
colo
gy
scre
ens,
%
Under
the in
fluence
of alc
ohol (
posi
tive
case
s am
on
g those
test
ed)
To
tal,
%
Ma
les,
%
Fe
ma
les,
%
Eis
ele
et al.
19
87
U
S,
19
83
–1
98
4
13
–1
9
25
(7
6%
) 8
8%
1
8%
n
ot
rep
ort
ed
n
ot
rep
ort
ed
Ho
be
rma
n &
Ga
rfin
kel 1
98
8
US
, 1
97
5–
19
85
<
20
2
29
(8
0%
) n
ot
rep
ort
ed
2
8%
1
no
t re
po
rte
d 2
n
ot
rep
ort
ed
2
Ald
rid
ge
& S
t Jo
hn
19
91
C
an
ad
a,
19
77
–1
98
8
10
–1
9
63
(8
4%
) n
ot
rep
ort
ed
2
1%
n
ot
rep
ort
ed
n
ot
rep
ort
ed
Ma
rttu
ne
n e
t al.
19
92
F
inla
nd
, 1
98
7–
19
88
1
3–
19
5
3 (
83
%)
94
%
51
%
50
%
56
%
Grø
ho
lt et al.
19
97
, 1
99
9
No
rwa
y, 1
99
0–
19
92
8
–1
9
12
9 (
77
%)
79
%
45
%
ap
pr.
45
%
ap
pr.
40
%
Bre
nt
et al.
19
99
U
S,
19
84
–1
99
4
13
–1
9
14
0 (
85
%)
no
t re
po
rte
d
29
% 3
3
2%
1
5%
Wein
berg
er
et
al.
20
01
U
S,
19
96
–1
99
7
11
–1
6
46
(7
4%
) 1
00
%
11
%
no
t re
po
rte
d
no
t re
po
rte
d
Johanss
on e
t al.
20
05
S
we
de
n,
19
81
–2
00
0
13
–1
9
88
(7
5%
) a
pp
r. 9
7%
3
5%
a
pp
r. 4
0%
a
pp
r. 2
0%
Shie
lds
et al.
20
06
U
S,
19
93
–2
00
2
11
–1
7
10
8 (
89
%)
94
%
17
%
no
t re
po
rte
d
no
t re
po
rte
d
Sin
gh
& L
ath
rop
20
08
U
S,
19
79
–2
00
5
9–
17
4
33
(7
9%
) n
ot
rep
ort
ed
2
0%
2
3%
3
9%
3
Ka
rch
et al.
2013
U
S,
2005–2008
10–17
1046 (
not
report
ed
) appr.
75
%
ap
pr.
10
%
no
t re
po
rte
d
no
t re
po
rte
d
1 E
viden
ce o
f pro
bable
alc
oh
ol c
on
sum
ptio
n (
base
d o
n o
bse
rvers
’ report
s) in
anoth
er
17%
. 2 M
ale
s and fem
ale
s equally
like
ly to
have
been u
nder
the in
fluence
of alc
ohol;
figure
s n
ot pro
vided.
3 F
igure
s ca
lcula
ted b
ase
d o
n in
form
atio
n in
the a
rtic
le t
ext
.
29
2.4.2 Previous suicide attempt and self-harm
A history involving a prior suicide attempt has consistently been shown to be one
of the strongest risk factors in adolescent completed suicide (Brent et al. 1999,
Grøholt et al. 1997, Shaffer et al. 1996). More female (36–67%) than male (12–
37%) adolescent suicide victims have previously attempted suicide (Brent et al. 1999, Grøholt et al. 1999, Hoberman & Garfinkel 1988, Karch et al. 2013,
Marttunen et al. 1992, Marttunen et al. 1995, Shaffer et al. 1996, Soor et al. 2012,
Weinberger et al. 2001), which is similar to the situation amongst the general
adolescent population (Evans et al. 2005, Hultén et al. 2001, Lewinsohn et al. 2001). It has been suggested that a previous suicide attempt increases the risk of
suicide among male adolescents in particular, the predictive value being less
important in females (American Academy of Child and Adolescent Psychiatry
2001, Gould et al. 2003), but this interpretation does not seem justifiable when
we examine original data from case-control studies that employ the psychological
autopsy method (Brent et al. 1999, Shaffer et al. 1996).
Self-cutting in adolescents is often regarded as low-risk behavior. However, a
study from the United Kingdom explored the long-term outcomes of self-harm
among <19-year-old children and adolescents and found that self-cutting was
strongly associated with the risk of suicide. Importantly, the study showed that
self-cutting conveyed a greater risk of suicide than self-poisoning. (Hawton et al. 2012a)
2.4.3 Familial and psychosocial risk factors
Parental psychopathology (most commonly, depression and substance use) and a
family history of suicidal behavior are risk factors in adolescent suicide (Brent et al. 1996, Gould et al. 1996). Case-control studies have shown that parental
divorce/separation is more common in the families of suicide victims than in
those of controls, but the association decreases when parental psychopathology is
accounted for (Gould et al. 2003).
Both in the longer term and shortly before a suicide, stressful life events, such
as interpersonal losses and conflicts, discord, and legal and disciplinary problems
are more common among adolescent suicide victims than among controls (Bridge
et al. 2006, Gould et al. 2003). In the latter case, the stressors are referred to as
precipitating factors or precipitants. Marttunen et al. (1993) described a
precipitant as a stressor that occurred during the month preceding the suicide and
30
that is believed to have directly contributed to it. An argument with one’s parents
is more common among child and young adolescent suicide victims, while
arguments or end of a relationship with a boy/girlfriend is associated with
suicides among older adolescents (Brent et al. 1999, Grøholt et al. 1998). A
precipitating factor was reported in 45% of male and 50% of female adolescent
suicides in a Norwegian study (Grøholt et al. 1999) and in 70% and 64% of all
adolescent suicide cases in studies conducted in Finland and the US, respectively
(Marttunen et al. 1993, Rich et al. 1990). One study from the US reported that a
precipitating event occurred on the day of the suicide in the case of 33% of
suicide victims under 18 years old (Barber 2005).
2.4.4 Availability of lethal methods
Much of the literature on the association between adolescent suicides and the
availability of lethal methods focuses on the use of firearms and largely originates
in the US, where use of firearms is the leading method of suicide among
adolescent males (Lubell et al. 2007). Results of ecological studies have
suggested that areas with a higher availability of firearms have higher rates of
suicide (Birckmayer & Hemenway 2001, Miller & Hemenway 1999, Miller et al. 2002, Miller et al. 2007). Further, studies indicate that this association is
relatively more important in suicides among adolescents and young people than in
the adult population (Birckmayer & Hemenway 2001, Miller et al. 2002, Miller et al. 2007, Sloan et al. 1990). More robust empirical evidence concerning the
association between firearms availability and adolescent suicide can be found in
case-control studies (Miller & Hemenway 1999). Such studies have shown that
the presence of a firearm in the home is associated with a higher risk of
adolescent suicide (Brent et al. 1988, Brent et al. 1991, Brent et al. 1993c, Shah
et al. 2000). With regard to age differences, Brent et al. (1999) have suggested
that availability of lethal means may play a greater role among younger than older
adolescents. Furthermore, there is some evidence that a firearm in the home is
associated with a particularly high risk of suicide among adolescents with no
discernible psychopathology (Brent et al. 1999). The role of impulsivity has been
emphasized in this respect (Brent & Bridge 2003).
31
2.4.5 Suicide contagion and clusters
It is recognized that some suicides occur in clusters, supporting the view that
suicide can be contagious behavior (Niedzwiedz et al. 2014). There are two main
patterns of suicide clusters: point clusters (localized in space and time, therefore
also known as space-time clusters) and mass clusters (media related, localized in
time only) (Haw et al. 2013, Joiner 1999, Mesoudi 2009). Regarding mass
clusters, the evidence indicates that the number of suicides increases following
mass media reporting of suicide – so-called copycat behavior or the Werther
effect (Mesoudi 2009, Niederkrotenthaler et al. 2010). Mesoudi (2009) defines
point cluster as a temporary increase in the frequency of suicides within a small
community or institution, relative to both the baseline suicide rate before and after
the point cluster and the suicide rate in neighboring areas. According to a recent
systematic review study, the evidence suggests a greater risk of point suicide
clustering among adolescents compared with older age groups (Niedzwiedz et al. 2014). However, point clustering has been reported as being a factor in less than
5% of suicides among adolescents and young people (Gould et al. 1990, Jones et al. 2013b).
The internet’s role in adolescent suicide contagion is currently a subject of
interest (Olson 2013, Robertson et al. 2012), but little research has been done on
the topic. A systematic review concluded that internet use may have both positive
effects, such as functioning as a support network, and negative effects, such as
normalizing self-harm and increasing suicidal ideation and hopelessness, on
young people who are at risk of self-harm or suicide (Daine et al. 2013).
2.5 Seasonal and other temporal patterns of suicide
Seasonal variation in suicide occurrence is a classic subject of interest in
psychiatric research. Conventionally, seasonality is defined as a “cyclical change
related to seasons of the year”, although nowadays the term is sometimes used to
refer to periodic fluctuations of any kind (Ajdacic-Gross et al. 2010a). Apart from
seasonal patterns, shorter-term temporal variations have been reported in
accordance with the day of the week and time of day (Law & De Leo 2013).
Seasonal variation in suicides among the general population, with peaks
during the spring and early summer, has been well documented in the medical
literature (Ajdacic-Gross et al. 2010a, Christodoulou et al. 2012). This general
pattern is known to vary between subpopulations according to the suicide method,
32
gender, and age (Ajdacic-Gross et al. 2010a, Christodoulou et al. 2012).
However, seasonality of suicides among adolescents is a poorly studied area, the
current, inconsistent findings being based on just a few published reports. Studies
from the US (Hoberman & Garfinkel 1988), Canada (Aldridge & St John 1991)
and Turkey (Uzun et al. 2009) identified no seasonality in <20-year-old
adolescent suicides. Another study from Canada (Thompson 1987) revealed a fall
peak among <21-year-old males. In the US, a September peak has been
demonstrated among 11–17-year-old children and adolescents (Shields et al. 2006) and fall and winter peaks among <16-year-old males (McCleary et al. 1991). Dervic et al. (2006) identified discrete suicide peaks in the spring and fall,
i.e. a bimodal seasonal trend, for <15-year-old Austrian children and adolescents.
In Norway, 63% of <16-year-old males and 75% of females of the same age who
committed suicide, did so “during the dark season”, i.e. between September and
February (Freuchen et al. 2012).
With regard to shorter-term fluctuations in the occurrence of suicide, an
excess of suicides on Mondays amongst the general population has been reported
(Maldonado & Kraus 1991, Miller et al. 2012), although an increased risk over
the weekend days was observed in a Finnish study (Partonen et al. 2004).
Findings from adolescent suicides have rarely been reported. In one study, a peak
on Saturday (30% of all suicides) was observed (Aldridge & St John 1991).
Another study found that 44% of adolescent suicide-related deaths occurred
between Friday and Sunday (Johansson et al. 2005) – a figure very close to what
would be expected if the suicides were distributed evenly throughout the days of
the week. 55% of suicides among <16-year-old Norwegian females were
committed on Monday, and only 17% of male suicides occurred between Friday
and Sunday (Freuchen et al. 2012). In terms of the time of day, a peak in suicides
during the late morning hours has been demonstrated amongst the general
population (Gallerani et al. 1996, Preti & Miotto 2001), whereas the peak for
younger people (14–24 years) occurred in the late afternoon (Preti & Miotto
2001). Similarly, a preponderance of suicides in the afternoon or evening has been
reported among <20-year-old (Hoberman & Garfinkel 1988) and <16-year-old
(Freuchen et al. 2012) suicide victims.
2.6 Child and adolescent suicide prevention
It is a widely accepted view that, in order to be effective, suicide prevention
efforts need to be comprehensive, multimodal and integrated (Lönnqvist et al.
33
2011, Mann et al. 2005, Schwartz-Lifshitz et al. 2012). Suicide prevention
strategies can be conceptualized using a model based on Universal, Selected and
Indicated preventive approaches (the USI model) (Dumon & Portzky 2013a).
While universal strategies target the entire population (or large subgroups such as
adolescents), selective strategies address subgroups of the total population that
have an above average risk of suicide. Indicated prevention strategies target
individuals who are at specifically high risk of suicidal behaviors, such as those
with suicidal thoughts. (Dumon & Portzky 2013a, Nordentoft 2011, U.S.
Department of Health and Human Services (HHS) Office of the Surgeon General
and National Action Alliance for Suicide Prevention 2012)
The low base rate of suicides entails methodological problems in
demonstrating the efficacy of various suicide prevention measures, since very
large studies with long follow-up periods would be needed in order to conduct
research with completed suicide as an outcome (Robinson et al. 2011). Due to
these practical considerations, not to mention ethical ones, in this field it is
practically impossible to perform randomized controlled trials, with ecological or
individually based naturalistic studies being carried out instead (Nordentoft
2011). Robust scientific evidence on the efficacy of most suicide prevention
approaches is therefore largely lacking. The evidence used in suicide prevention
may be imperfect from the scientific perspective, but given the significance of
suicide as a serious public health concern preventive acts and recommendations
must rely on the best available knowledge (Campo 2009, Nordentoft 2011).
In the following review of suicide prevention approaches, the emphasis is on
the strategies considered most relevant to adolescents.
2.6.1 Universal suicide prevention
School-based programs
Compared to suicide prevention measures amongst the general population, a
specific dimension of child and adolescent suicide prevention lies in the fact that
most young people attend school. A school setting therefore seems a natural
standpoint from which to target virtually all individuals in this age group.
Suicide awareness programs number among the most commonly applied
adolescent suicide prevention programs (Portzky & van Heeringen 2006). Among
the main goals of these programs are enhancing help-seeking behavior and
34
providing adolescents with the information they need to identify at-risk peers,
followed by confiding in responsible adults (since suicidal adolescents are much
less likely to talk to adults than to peers in times of distress) (Berman et al. 2006,
Brown et al. 2007, Gould et al. 2003). However, no firm evidence exists on the
positive impact of these programs on reducing suicidal behavior (van der Feltz-
Cornelis et al. 2011). As reviewed by Gould et al. (2003), Mann et al. (2005) and
Pelkonen and Marttunen (2003), whereas positive effects have sometimes been
observed, indifferent and even unfavorable effects have been reported, such as
negative reactions among suicidal adolescents and a decreased likelihood of
recommending mental health evaluations to a suicidal peer. It is also
acknowledged that changes in behavior are not necessarily brought about by
changes in knowledge and attitudes (Berman et al. 2006). The emphasis has
therefore been shifted toward other school-based strategies, including skills
training programs focusing e.g. on the problem-solving and cognitive skills of the
adolescents in question (Bridge et al. 2006, Gould et al. 2003). Although no direct
causal relationship can be established between skills training programs and
reduced suicide rates, improvements in other factors such as distress coping skills
are regarded as being of importance in general.
Media education
Since considerable evidence exists of suicide contagion, a plausible intervention
option would involve influencing media reporting on suicides. Accordingly,
media guidelines have been published (Dumon & Portzky 2013b, World Health
Organization 2008), including descriptions of factors that should be avoided (such
as portraying suicides in a glamorizing or romanticizing manner, or disclosing the
method and location of suicide) and suggestions for enhancing the positive role
played by the media in suicide prevention efforts (such as providing information
on the help available and stressing the multifactorial nature of suicidal acts).
Method restriction
Restricting access to lethal means of suicide is a key and evidence-based suicide
prevention strategy at the population level (Florentine & Crane 2010, Mann et al. 2005, Yip et al. 2012). The background rationale for this approach lies in the idea
that ambivalence about life and death is common among suicidal individuals, the
suicidal intent “waxes and wanes”, and periods of high risk are often of short
35
duration. Restricting access to suicide methods during this short period may
therefore have the potential to prevent suicides (Florentine & Crane 2010). At the
same time, it is acknowledged that such a suicide prevention approach does not
address the underlying causes of suicide (Hawton 2005).
The substitution hypothesis constitutes a potential dilemma in relation to the
method restriction approach. This hypothesis states that if access to one method
of suicide is restricted, another will be used instead (Florentine & Crane 2010).
However, there is some evidence that suicidal individuals have a preference for a
specific method of suicide and tend not to switch easily from one to the other
(Daigle 2005).
One of the most intensely studied areas of the method restriction strategy is
controlling access to firearms. Not only has it been shown that the availability of
firearms increases the risk of adolescent suicide by such means, but several
studies have also concluded that adolescent firearm suicide rates fall following
stricter regulation of such access (Beautrais et al. 2006, Cheung & Dewa 2005,
Lubin et al. 2010, Niederkrotenthaler et al. 2010, Webster et al. 2004). Examples
of other method restriction approaches shown to reduce suicide rates among the
general population include packing analgesics in blister packets and limiting
packet size, detoxification of domestic gas, restrictions on pesticides, and the
construction of barriers at jumping sites (Nordentoft 2011, van der Feltz-Cornelis
et al. 2011).
2.6.2 Selected suicide prevention
The aim of this approach is to prevent the onset of suicidal behaviors among
specific above-average risk subpopulations (Dumon & Portzky 2013a). Since
psychiatric disorder is a salient risk factor in adolescent suicides, those with
mental illnesses are the most important risk group with respect to prospective use
of the selected suicide prevention approach.
Screening and gatekeeper education
A screening strategy involves the use of self-report and individual interviews to
identify at-risk adolescents, with subsequent referral for treatment (Gould et al. 2006). A potential problem in this approach is the relatively high rate of false
positives. Although even non-suicidal adolescents would probably benefit from
interventions, the downside is the large burden imposed on limited mental health
36
resources (Horowitz et al. 2009). Suicide screening programs in schools are
popular in the US, yet a review study concluded that, given the weak evidence
base demonstrating the effect of this approach in reducing suicidal behaviors,
“efforts to use such programs should be regarded as investigational in nature”
(Peña & Caine 2006).
The rationale for gatekeeper education is that by educating adults (such as
school personnel) who meet adolescents on an everyday basis about suicide risk
factors, the identification of at-risk adolescents could be improved. In their
review, Gould et al. (2003) concluded that the research findings are encouraging,
pointing to improvements in e.g. knowledge, attitudes and referral practices
among school personnel, while the amount of research is limited.
Treatment of psychiatric disorders
In reducing suicidal behaviors, the effectiveness of treatment of adolescent
psychiatric disorders provides the fundamental grounds for high-risk suicide
prevention strategies. Because mood disorders are the most common diagnostic
risk factors involved in adolescent suicide, most research has focused on the
treatment of depression (Pelkonen & Marttunen 2003). A review of adolescent
depression treatment approaches would be beyond the scope of this literature
review, but it should be mentioned that psychotherapy and use of antidepressants
are commonly accepted evidence-based treatments (Thapar et al. 2010).
Regarding antidepressant treatment and suicidal behavior in children and
adolescents, during the first decade of the 21st century concerns emerged about
the possible adverse effect of antidepressants in provoking suicidal behavior
among adolescents (Hammad et al. 2006). Subsequently, “black box warnings”
were issued by the US Food and Drug Administration (FDA) (Leslie et al. 2005).
However, the subject remains controversial (Cooper et al. 2014, Isacsson & Rich
2014).
2.6.3 Indicated suicide prevention
The indicated suicide prevention approach focuses on the high-risk group of
adolescents who have already attempted suicide, or who are at specifically high
risk of suicidal behaviors, such as those with suicidal thoughts (Dumon & Portzky
2013a). As previously noted, a history of prior suicide attempts is one of the most
potent risk factors in terms of adolescent suicides. It should be noted, however,
37
that only a minority of adolescents who engage in self-harm and attempt suicide
seek treatment or present to hospitals (Bridge et al. 2006, Hawton et al. 2012b). A
large proportion of these high-risk individuals may therefore remain unknown to
health care professionals.
In cases of suicidal crisis, guidelines commonly recommend that adolescents
be referred to inpatient care (American Academy of Child and Adolescent
Psychiatry 2001). Although intensive treatment based on skilled observation and
support are offered in hospital settings, no empirical evidence exists on the
effectiveness of this treatment in reducing rates of completed suicides (Gould et al. 2003).
A recent review (Robinson et al. 2011) studied randomized, controlled trials
testing interventions in the case of adolescents and young adults who had attended
a clinical setting due to suicidal behavior or deliberate self-harm. The outcome
measures were suicidal behavior, ideation, and/or deliberate self-harm. The
review concluded that no differences were found between treatment and control
groups, except for one study in which favorable outcomes emerged in an
individual cognitive therapy group compared to treatment as usual (i.e. standard
treatment used in clinical practice) received by a control group. The authors of the
review remarked that the sample sizes were far too small to enable a study of the
effectiveness of treatments in preventing completed suicides.
38
39
3 Aims of the study
The purpose of this work was to investigate the epidemiology of child and
adolescent suicides in Finland, with a special focus on gender differences. The
specific aims were:
1. To examine national trends in rates and methods of child and adolescent
suicides in 1969–2012 in Finland (I).
2. To analyze the regional difference between Northern and Southern Finland in
rates of firearm suicides among male children and adolescents in 1972–2009
(II).
3. To explore the characteristics of child and adolescent suicides, including
demographic, psychosocial and situational factors, use of alcohol, previous
suicidality and the psychiatric inpatient treatment histories of the suicide
victims, and seasonal pattern of the suicides in the province of Oulu between
the years 1988–2012 (III, IV).
Hereafter, the Roman numerals I–IV refer to the original publications.
40
41
4 Material and methods
4.1 Suicide data
The data presented in this thesis are based on information from official documents
concerning deaths classified as suicides by medical examiners. Regarding death
certification practices, Finnish law requires that the police conduct an
investigation into the cause of death and request a medicolegal autopsy 1) when a
person’s death is due or is suspected of being due to a criminal offence, an
accident, suicide, intoxication, an occupational disease or medical treatment, 2)
when a person has died from an unknown disease or did not receive medical
treatment during their last illness, and 3) when the death was otherwise
unexpected (Act on the Inquest into the Cause of Death 1973).
As stated above, in Finland medicolegal autopsy is performed in every case
in which the actual or suspected cause of death was suicide. Medicolegal
autopsies are performed by official medical examiners who are forensic
pathologists. They make the final decision on the cause and manner of the death
and issue the death certificate once the information acquired from the autopsy is
complete and the necessary background information, such as medical history and
recent life events, has been gathered on the deceased. The data included in this
thesis refer only to deaths classified as suicides, whereas deaths classified as
being of undetermined cause did not qualify for the study.
4.1.1 Macro approach (I, II)
The data for the macro-level studies (I, II) were obtained from the Finnish Cause
of Death register, which is produced by Statistics Finland (Statistics Finland
2013). Statistics on the cause of death cover persons who have died in Finland or
abroad and were permanently resident in Finland at the time of their death. The
Cause of Death Register is based on data from death certificates and includes
information on the cause and manner of death, the date and place of death, and
the person’s exact birth date, personal identity code, age, gender and place of
residence. Since 1996, causes of death have been coded according to the 10th
revision of the International Statistical Classification of Diseases and Related
Health Problems (ICD-10). In 1969–1986, such statistics were compiled
according to ICD-8, and ICD-9 was used in 1987–1995.
42
For the purposes of this study, deaths classified as suicides were extracted
from the Causes of Death Register. The diagnostic codes used for suicides were
E950–959 of ICD-8 and ICD-9 in 1969–1995, and codes X60–X84 and Y87.0 of
ICD-10 since 1996. The classification of specific suicide methods in various
revisions of ICD is illustrated in Table 4.
Table 4. Classification of suicide methods in ICD-8, ICD-9 and ICD-10.
Method of suicide ICD-8
(used in 1969–1986)
ICD-9
(used in 1987–1995)
ICD-10
(used since 1996)
Poisoning E950 E950 X60–X65, X68–X69
Gassing E952 E951–E952 X66–X67
Hanging E953 E953 X70
Drowning E954 E954 X71
Use of firearms E955 E955 X72–X75
Jumping from a high place E957 E957 X80
Other methods E956, E958–E959 E956, E959 X76–X79, X81–X84, Y87.0
Traffic suicides not specified E959A–E959B X81–X82
Other/Unspecified E956, E958–E959 E956, E959 X76–X79, X83–X84, Y87.0
Year-end population estimates for specific age groups were also obtained from
Statistics Finland, in order to calculate age-standardized suicide mortality rates,
i.e. annual suicide rates per 100,000 population. An age limit of 12–17 years was
chosen for the adolescent population, because suicides among persons younger
than 12 years of age are extremely rare.
Adolescent suicide trends in Finland (I)
The data derived from the original publication I cover all suicides committed by
under 18-year-old children and adolescents (hereafter referred to as
“adolescents”) between 1st January 1969 and 31st December 2008 in Finland. In
this study, trends in overall and method-specific suicide rates among male and
female adolescents were investigated. The suicide methods presented in Table 4
were further classified into violent methods (use of firearms, hanging, jumping
from a high place, drowning), non-violent ones (poisoning and gassing) and
others.
At the time the data was purchased, Statistics Finland classified suicide
methods according to ICD-9 (from 1987 until 1997). Nowadays, the causes of
43
death classification follows the year limits used in the official classification of
diseases described in Table 4.
This thesis also includes unpublished results for updated suicide trends. The
updated data includes the years 2009–2012.
Adolescent male firearm suicides in Northern and Southern Finland (II)
Data derived from the original publication II cover all male adolescent suicides
committed with firearms in Northern and Southern Finland between 1st January
1972 and 31st December 2009. As reference groups, the data also includes firearm
suicides by males aged 18–24 years (hereafter referred to as “young adults”) and
25–44 years (“adults”). Rates of adolescent male firearm suicides in Northern
Finland and Southern Finland are compared. The study regions are illustrated in
Figure 1.
44
Fig. 1. Study regions: Northern and Southern Finland and the province of Oulu.
In ICD-8 and ICD-9, only one diagnostic code (E955) was used for firearm and
explosive suicides. In ICD-10, firearm suicides were classified as follows:
handgun discharge (X72); rifle, shotgun and larger firearm discharge (X73); other
and unspecified firearm discharge (X74); explosive material (X75). Since
information on specific types of firearm was not recorded before 1996, type-
specific firearm results can only be reported from that year onwards.
The characteristics of Northern and Southern Finland are presented in Table 1
of the original publication II. A major difference between the study regions lies in
the greater number of firearms per person in the north (50/100 persons in
45
Northern Finland vs. 27/100 persons in Southern Finland) (The Finnish Police,
unpublished data).
4.1.2 Micro approach (III, IV)
Data from the “Suicides in the province of Oulu” research project
Data on micro-level studies originate in the “Suicides in the province of Oulu”
research project, which was initiated in 1988. This includes all suicides
committed in the province of Oulu since 1st April 1988. Such data is collected by
the Department of Psychiatry, University of Oulu, in collaboration with the
competent authority in charge of forensic medicine. In the province of Oulu, this
competent authority was the Department of Forensic Medicine of Oulu University
until 2009 and the National Institute for Health and Welfare from 2010.
The province of Oulu, situated in Northern Finland, is shown in Figure 1. The
area will be referred to under that name in this thesis, although as of the beginning
of 2010 the Finnish provinces were abolished and the former area of the province
of Oulu is now administered by the Regional State Administrative Agency for
Northern Finland. The province of Oulu is a geographically extensive area
covering 19% of Finland’s land area, while the population accounted for 9%
(n=480 000) of the total population of Finland in 2014 (Statistics Finland 2014b).
The data used in the “Suicides in the province of Oulu” research project are
based on documentation related to establishing the cause of death during
medicolegal autopsy investigations. Related sources of information are illustrated
in Table 5. Primary source of data consists of death certificates in which suicide
has been classified as the manner of death by official medical examiners. Data
extracted from death certificates include age, gender, method of suicide, date and
place of death, contributory cause(s) of death (defined as reasons adversely
affecting the development of the condition leading to death and hence
contributing to it) (Statistics Finland 2013), and the presence of alcohol in the
blood at the time of death (use of alcohol coded as the contributory cause of
death). In addition to their structured data fields, the death certificates include a
blank text field for event description, i.e. a short case history written in the form
of free text (Lahti & Penttilä 2001). Such a case history usually includes
background information on issues such as the previous suicidality of the
deceased, or critical life events prior to suicide. The type of firearm used in
46
firearm suicides is always noted in the event description. Appendix 1 presents a
copy of the Finnish death certificate form.
Table 5. Sources of information for the “Suicides in the province of Oulu” research
project.
Information source Specific information source Original
publication
Documents pertaining to
establishing the cause of death
Primary source Death certificates III, IV
Other sources Autopsy referrals III
Police investigation reports
Findings of the external and internal examinations of
the medicolegal autopsies
Microscopic examinations
Toxicological examinations
Final medicolegal autopsy reports
Register linkage data Finnish Hospital Discharge Register III
Other sources of information are also presented in Table 5. Autopsy referrals are
written by primary care physicians and often include information on the
deceased’s prior state of health. Most police investigation reports include
information based on interviews with next-of-kin or others who knew the
deceased, and copies or mentions of possible suicide notes. Detailed external and
internal examinations of the body are conducted by official medical examiners,
who also take tissue samples for microscopic examination. Toxicological
examinations include, for example, the determination of alcohol and drug
concentrations in the blood and urine. All toxicological analyses are performed in
the Forensic Toxicology Laboratory at the Department of Forensic Medicine Hjelt
Institute of the University of Helsinki. Final medicolegal autopsy reports are
written by medical examiners based on all of the above information.
National health care register information was also used as a source of data. In
Finland, it is possible to make register linkages using the personal identity codes
with which every Finnish citizen is provided. The suicide data was linked to the
Finnish Hospital Discharge Register (FHDR, renamed as the Care Register for
Health Care in 1994), a nationwide health register covering all inpatient hospital
admissions at primary and specialized level care in Finland since 1969 (Sund
2012). The FHDR data contain primary diagnoses and comorbidities upon
47
discharge, as well as the length of stay and discharge dates for all treatment
episodes. Such data is provided by the National Institute for Health and Welfare.
Adolescent suicide data (III, IV)
The study sample in the original publication III comprised all 58 adolescents
below 18 years of age who committed suicide in the province of Oulu between 1st
April 1988 and 31st December 2012. Among the documents pertaining to
establishing the cause of death, death certificates were available for all subjects.
In terms of other documents, these were available for 54 (93%) adolescents and,
due to administrative obstacles, unavailable for four male subjects. Among the 54
suicide victims, the medical examiners’ suicide case files included documents of
all other kinds, except for autopsy referrals (or equivalent documents) which were
available for 56% of the subjects. In addition, while the content of toxicological
examinations varied, the blood alcohol concentration (BAC) was available for all
subjects.
For the purpose of this research, besides data derived from the death
certificates, information extracted primarily from the other documents included
blood and urine alcohol concentrations, the presence and concentrations of
substances other than alcohol in the blood and urine, the time of suicide, the
presence of a suicide note, the family circumstances and living arrangements of
the adolescents, precipitating factors (defined as a recent stressor believed to have
directly contributed to the suicide), the psychological and behavioral
characteristics of the adolescent, previous suicidality (expression of suicidal ideas
or a suicide attempt) and self-cutting. Self-cutting was defined as distinctive scars
detected by a medical examiner in an external examination of the body. A
previous suicide attempt was considered to be present if “suicide attempt” was
mentioned in any of the documents. As described in section 4.1.1., suicide
methods were categorized as violent or non-violent.
Blood alcohol concentrations are reported in line with the Finnish standards
on the issue, i.e. as mass of alcohol per mass of blood (1 mg/g, indicating 1 per
mil (‰)), in contrast to many other countries which use mass of alcohol per
volume of blood (e.g. 1 g/L) as the unit of measurement (Jones 2006). A cut-off
concentration of 0.20 g/L (i.e. 0.19 mg/g, or 0.19‰) was used when reporting
positive blood alcohol results (Jones et al. 2013a), due to the risk of small
amounts of alcohol being generated in the body after death.
48
In the original publication IV, the seasonal distribution of adolescent suicides
(n=42) was examined for the period 1988–2005. Adult suicides (≥18 years) were
used as a comparison group. Since the seasonality of suicide differs by method
and the use of firearms was the most common suicide method among the
adolescents studied, only the seasonality of firearm suicides was investigated.
Seasonal patterns among adolescent and adult firearm suicides were compared
with one another and with the uniform distribution of suicide cases over the year.
Additionally, the seasonal pattern of firearm suicides within a subgroup of young
adults aged 18–23 years was compared with that of the rest of the adult
population (≥24 years).
The distribution of suicides was investigated by both month and season. The
seasons were defined as follows: winter (November to January), spring (February
to April), summer (May to July) and fall (August to October). As such, they
follow the occurrence of solstices and equinoxes and are based on the amount of
light, which in Northern Finland peaks in June and troughs in December. Monthly
mean sunshine hours during the period 1971–2000 in the province of Oulu were
obtained from official publications by the Finnish Meteorological Institute (2004).
This thesis also includes unpublished results based on updated suicide
seasonality data related to adolescent suicides up to the year 2012. For male
adolescents, the updated results are presented as overall data, and separately for
firearm suicides and for suicides by all other methods. With respect to adolescent
females, due to the small number of cases the updated results are presented for
total data only.
Further, this thesis presents unpublished data based on the results of forensic
toxicology examinations, which include results related to alcohol concentrations
in the blood (BAC) and urine (UAC). The stage of alcohol metabolism in suicide
victims at the time of death, i.e. whether they committed suicide during the
ascending or descending phase of blood alcohol concentration, can be assessed by
calculating the ratio of UAC and BAC. The UAC/BAC ratio also serves as an
indicator of the time which elapsed between the point at which drinking ended
and death (Jones 2006).
As regards alcohol metabolism, alcohol is absorbed into the circulatory
system from the stomach and gut, whereby the BAC begins to increase. The
alcohol is then distributed throughout the body (Kugelberg & Jones 2007). The
UAC begins to increase, although at a lower rate than the BAC, when alcohol
passes into the kidneys from blood carried by the renal artery (Jones 2006).
During the initial 60–120 minutes after alcohol consumption, the UAC is less
49
than or equal to the BAC during the absorptive phase, as the BAC increases
(ascending phase of the blood alcohol concentration), and slightly higher than the
BAC during the plateau phase (an “intermediate period” denoting that alcohol is
still being absorbed, but no increase in BAC is occurring due to the elimination
process simultaneously occurring in the liver). In the post-absorptive phase, i.e.
approximately >120 minutes after drinking, as the BAC is decreasing due to
alcohol metabolism in the liver (the descending phase of the blood alcohol
concentration), the UAC is higher than the BAC due to the higher water content
of the urine (~100%) compared with that of the blood (~80%). (Jones 2006, Jones
& Kugelberg 2010) Following alcohol consumption, the UAC/BAC ratio
therefore changes as a function of time. A relatively low UAC/BAC ratio (<1.0)
suggests that the absorptive phase was under way at the time of death, indicating
that the individual had been drinking alcohol fairly recently, around one hour
before death. A UAC/BAC ratio between 1.0 and 1.2 suggests that the decedent
was in the plateau phase, while a ratio greater than 1.2 is indicative of the
complete absorption and distribution of alcohol (post-absorptive phase), implying
that most of the alcohol was consumed several hours before death. (Jones 2006,
Kugelberg & Jones 2007, Levine & Smialek 2000)
UAC/BAC ratios were calculated for all adolescent suicide victims who were
under the influence of alcohol at the time of their death, except for one subject
whose forensic toxicology results were not available (but use of alcohol was
recorded on the death certificate). The proportion of adolescents in the ascending
phase (UAC/BAC ratio ≤1.2) and in the descending phase (UAC/BAC ratio >1.2)
of blood alcohol concentrations at the time of suicide was determined. To
calculate the UAC/BAC ratios, BAC units of 1 mg/g were converted into 1 g/L to
enable use of the aforementioned cut-off value of 1.2, which is based on mass per
volume measurements (Levine & Smialek 2000). Since the water content of urine
is close to 100%, i.e. its density is almost 1.0, conversion of units is not required
for UAC values (Jones 2006).
4.2 Statistical methods
The statistical significances of the group differences in categorical variables were
assessed using Pearson’s chi-squared test or Fisher’s exact test, and in continuous
variables using Student’s t-test. In addition, the specific statistical analyses used
in the original publications are presented below.
50
Original publication I. For the analysis of suicide trends, a Joinpoint
regression model was employed in order to identify changes in suicide rates over
time. A grid-search model was used to fit the regression function to unknown
joinpoints. In addition, the annual percent change (APC) was used to characterize
trends in suicide rates over time and the model suggested by the Joinpoint
regression analysis (Kim et al. 2000) was used as the best fit for the adolescent
suicide rate data per 100,000 population. The Joinpoint regression Program,
version 3.4.2 (http://srab.cancer.gov/joinpoint/) served as the software. Owing to
the relatively small number of adolescent suicides, three-year moving averages
were used for statistical modeling.
In analyzing trends in specific suicide methods, trends from the year 1975
onwards were examined. This was because during the time of study completion
method-specific suicide data were unavailable for 1969–1974. Since it is well
established that the year 1990 marked a notable turning point in overall suicide
rates in Finland, i.e. the rising trend turned to a decrease (Hiltunen et al. 2009),
these method-specific trends were examined separately for the years 1975–1989
and 1990–2008. From 1987, the “other methods” were split between traffic
suicides and other/unspecified methods, since due to a change in the statistical
practices used within Statistics Finland, a separate code was assigned to traffic
suicides (E959; X81–X82). When calculating the trend in violent suicides for the
period 1990–2008, traffic suicides were included in violent suicide methods.
Original publication II. Suicide rates were visualized as 3-year moving
average rates. Differences in suicide rates between Northern and Southern
Finland were analyzed using the Independent Samples t-test. Regression analysis
was used to test the linear trend in suicides.
Original publication III. Because this study was descriptive in nature, no
sophisticated analyses were performed. The data were analyzed by gender and
age group (<15 years and 15–17 years), where such an approach was considered
relevant.
Original publication IV. Overall seasonality was assessed using the chi-
square test for multinomials and the ratio of the observed to the expected number
of suicides was calculated with 95% confidence intervals (Wonnacott &
Wonnacott 1990). Expected numbers of suicides were calculated based on the
uniform distribution of suicide cases over the year. Adjustment for equal month
length was performed and account was taken of the effect of leap years.
51
All statistical tests were two-tailed, and a limit for statistical significance was
set at p<0.05. The statistical software used in the analyses was SPSS Statistics
(IBM Corp. 2013).
4.3 Ethical considerations and personal involvement
The research plan for the “Suicides in the province of Oulu” project, of which the
micro approach section of the present research forms part, was approved by the
Ethics committee of the Faculty of Medicine, University of Oulu on 8th November
1999, and by the Ministry of Social Affairs and Health on 22nd May 2000 (Dnro
14/07/2000). The data used in this study are solely based on administrative
documents and information culled from Finnish national registers. The topic of
this doctoral thesis was approved by the Postgraduate Research Committee of the
Faculty of Medicine at the University of Oulu on 16th December 2008.
Suicide in children and adolescents is a particularly sensitive topic, and
careful consideration must be given to the publication and presentation of study
results related to this subject. The results of this study have therefore been
reported while maintaining the confidentiality of deceased children and
adolescents. Individual cases cannot be identified in any of the published results.
No family members or other people close to the suicide victims were contacted
and no interviews were performed at any stage of the research.
The author of this thesis has been participating as a researcher in the
“Suicides in the province of Oulu” study project since 2004. In addition, the
author has made a major contribution to all of the original publications, is named
as the first author in each of them, and was the corresponding author of
manuscripts I–III. She was involved in designing the study, collecting and
analyzing the data and reporting the results. Also, in consultation with a
professional statistician, she participated in the statistical analyses of all of the
original studies. She wrote the first draft of each manuscript and was responsible
for the final form of each paper as it was submitted.
52
53
5 Results
5.1 Macro approach (I, II)
5.1.1 Child and adolescent suicide trends in Finland (I)
In the original publication I, trends in overall and method-specific suicide rates
among Finnish male and female adolescents were explored. Over a period of 40
years between 1969 and 2008, there were 901 suicides among children and
adolescents under the age of 18 years in Finland. Of the suicide victims, 78%
(n=701) were male and 22% (n=200) female, giving a male-to-female ratio of
3.6:1.
Analysis based on the updated data showed that, over the period 1969–2012,
the number of adolescent suicides increased to 964, 77% of which (n=746) were
male and 23% (n=218) female suicides (unpublished data). In the additional
period 2009–2012, there were 45 (71%) male and 18 (29%) female suicides. The
male-to-female ratio for the years 2009–2012 was thus 2.5:1.
Overall trends in adolescent suicides
Figure 1 of the original publication I shows gender-specific adolescent suicide
trends between the years 1969 and 2008. Male adolescent suicide rates increased
significantly (p<0.001) in 1969–1989 and decreased after 1990 (p<0.001). Rates
among females were inconsistent during the earlier period, turning into a
significant increase (p<0.001) in the latter period.
Adolescent suicide trends were recalculated with updated data covering the
period up to the end of 2012 (unpublished data). As shown in Figure 2, the results
remained the same among adolescent males, except for the turn from a decreasing
trend towards an increase during the most recent years (change p=0.013). Female
adolescents also show similar results for the earlier years, but the rate has begun
to decrease slightly in more recent times (change p=0.007).
54
Fig. 2. Child and adolescent suicide trends in Finland in 1969–2012.
Trends in methods of suicide
Among male adolescents, use of firearms was the most common method of
suicide, as it was involved in 49% of all suicides in 1975–1989 and in 49% of all
suicides in 1990–2008 (I: Figure 2). The second most common suicide method
was hanging (35% in the earlier period and 26% in the latter period). The
proportion of all non-violent suicide methods among adolescent males was low
throughout the study period, as they accounted for 3% of all suicides in the earlier
period and 5% in the latter. As shown in Table 1 of the original publication I, no
significant changes occurred in rates of different methods of suicide among male
adolescents in the period 1975–1989. In 1990–2008, a significant decrease was
observed in suicides by the use of firearms, by poisoning and by all violent
methods. The decrease in suicides by all violent methods including traffic
suicides was likewise significant. There was no significant change in the rate of
all non-violent methods.
For female adolescents, the most common method of suicide was poisoning
(26%) in 1969–1989 and hanging (32%) in 1990–2008 (I: Figure 2). Hanging was
the second most common method (22%) in the earlier period, while other
55
methods (25%) were in the latter. Traffic suicides accounted for 96% of the other
methods. Among females, poisoning was the only non-violent method of suicide,
accounting for 26% of all suicides in the earlier period and 21% in the latter. As
presented in Table 2 in the original publication I, no significant changes in the
rates of any specific female suicide methods were observed during the period
1975–1989. In 1990–2008, a significant increase was observed in suicides by
“other methods”, especially traffic suicides. A significant increase was also
observed in violent suicides when traffic suicides were included. Rates of non-
violent suicides remained unchanged.
In a further analysis using updated data, the distribution of adolescent suicide
methods was examined for the most recent 5-year period (2008–2012)
(unpublished results). During this period, traffic suicides were the most common
method of suicide among both genders, as they accounted for 34% of all suicides
among males and for 35% among females. For males, the second and third most
common suicide methods were hanging (28%) and use of firearms (26%), and for
females hanging (27%) and jumping (19%). Non-violent methods accounted for
2% of all male and 12% of all female adolescent suicides.
5.1.2 Child and adolescent male firearm suicides (II)
In the original publication II, the regional difference in the rates of male
adolescent firearm suicides between Northern and Southern Finland was
examined. Of the total of 654 adolescent (<18 years) male suicides in Finland
between 1972 and 2009, 47% (n=305) were committed through the use of
firearms. In the reference groups of young adult (18–24 years) and adult (25–44
years) males, 36% (n=1,530) of the 4,252 young adult male suicides and 25%
(n=3,588) of the 14,674 adult male suicides were committed using firearms.
Regional differences in firearm suicide rates
Throughout the study period, 1972–2009, the mean rate of Finnish adolescent
male firearm suicides (per 100,000 population aged 12–17 years) was
significantly higher in Northern Finland than in Southern Finland (8.7 vs. 3.1,
p<0.001) (II: Figure 3a). The difference in rates between these regions was 2.8-
fold. A similar regional difference in firearm suicides was also observed among
young adult males, as the regional difference was 2.6-fold (33.8 vs. 13.2,
56
p>0.001) (II: Figure 3b) and, in adult males, firearm suicide rates involved a 1.9-
fold (22.0 vs. 11.4, p<0.001) difference between regions (II: Figure 3c).
Regarding the rates of suicide by other methods, no regional differences were
observed among adolescent males (4.8 vs. 4.3, p=0.176) or young adult males
(26.8 vs. 28.7, p=0.086). A significant difference was observed among adult
males (43.2 vs. 38.7, p=0.004).
Proportion of suicides involving firearms
Among adolescent males, the proportion of suicides involving firearms was
significantly higher in Northern Finland than Southern Finland (64% vs. 41%,
p<0.001) (II: Figure 4). A similar regional difference was also found among
young adult males (55% vs. 31%, p<0.001) and adult males (34% vs. 23%,
p<0.001). The highest proportion of suicides involving firearms was observed
among adolescent males in Northern Finland (64%) and the lowest among adult
males in Southern Finland (23%).
Types of firearms
The exact type of firearm involved was included in the diagnostic codes for
suicides from the year 1996, when ICD-10 was implemented in Finland. Type-
specific firearm results are therefore reported only for the years 1996–2009. A
shotgun or rifle (i.e. a hunting gun) was the most commonly used weapon in male
firearm suicides in all three age groups, both in Northern and Southern Finland
(II: Table 2). Among adolescent males, a hunting gun was involved in 88% of all
firearm suicides in Northern Finland, whereas the proportion was 67% in
Southern Finland (p=0.060). The regional difference was similar among young
adults (85% vs. 67%, p<0.001) and adult males (79% vs. 56%, p<0.001).
5.2 Micro approach (III, IV)
5.2.1 Demographic features of child and adolescent suicides (III)
The original publication III presented the characteristics of child and adolescent
suicides, with a special focus on gender differences. Of the total of 58 adolescent
suicide victims in the province of Oulu during 1988–2012, 79% (n=46) were male
57
and 21% (n=12) female. The male-to-female ratio was thus 3.8:1. Approximately
one fifth of both male (n=9) and female (n=2) suicide victims were under 15
years of age (III: Table 1) and the youngest suicide victim was 11 years of age. In
our sample, 17-year-old adolescents comprised almost half of all suicide victims,
the proportions being 43% (n=20) among males and 58% among females (n=7) in
(p=0.518).
With regard to the family circumstances and living arrangements of these
adolescents at the time of suicide, most had been living with at least one
biological parent (III: Table 1). Approximately one in ten of the males were
housed by child welfare services (institutions, relatives, foster family). Of the
adolescents living with at least one biological parent, at least half of the males and
two thirds of the females were living with both biological parents.
5.2.2 Suicide methods (III)
Use of firearms was the most common method of suicide in both genders, with
63% (n=29) of males and 33% (n=4) of females employing this method (III:
Table 1). Hanging was the second most common suicide method among the
males, accounting for 20% (n=9) of all male adolescent suicides. In addition, 9%
(n=4) of the males jumped from a height, 7% (n=3) committed suicide in traffic,
and 2% (n=1) committed suicide using exhaust gas. Of the adolescent females,
25% (n=3) committed suicide in traffic (railway suicides in all cases), 17% (n=2)
took a drug overdose, and hanging, a jump from a height and drowning were each
employed by one female. There was a significant difference in the distribution of
suicide methods between males and females (p=0.009).
In regard to violent and non-violent methods of suicide, with the exception of
one gassing suicide all male adolescent suicides were committed employing a
violent method (98%, n=45). Two females committed suicide by drug overdose,
meaning that the majority (83%, n=10) of adolescent females had used violent
suicide methods. No significant difference was observed in the choice between
violent and non-violent methods of suicide between the genders (p=0.106).
5.2.3 Mental health (III)
Table 6 summarizes the findings concerning the mental health status of adolescent
suicide victims. Evidence of mental health problems – defined as lifetime
inpatient hospital care due to a mental disorder or self-poisoning, a mental
58
disorder as a contributory cause of death in the death certificate, previous
suicidality (expression of suicidal ideas or a suicide attempt), self-cutting, or
nonspecific symptoms of mental health problems – was found in the majority of
adolescent suicide victims in both genders: 63% of males and 83% of females.
Table 6. Evidence of mental health problems among adolescent suicide victims, by
gender.
Evidence of mental health problems Males Females p-value1
n % n %
History of inpatient psychiatric hospitalization 7 15 2 17 1.000
History of inpatient somatic hospitalization due to
self-poisoning
– – 2 17 0.040
Mental disorder as a contributory cause of death
in the death certificate
4 9 3 25 0.147
Previous suicidality 14 30 9 75 0.020
Expression of suicidal ideas 13 28 7 58 0.086
Suicide attempt 2 4 3 25 0.055
Self-cutting 3 7 4 33 0.028
None of the above, but nonspecific symptoms of
mental health problems
7 15 1 8 1.000
Any of the above 29 63 10 83 0.302
No mental health problems by parental report 6 13 – – 0.328
Not reported 11 24 2 17 0.716 1 Fisher’s exact test, two-tailed significance
Lifetime inpatient psychiatric care
A history of inpatient psychiatric hospitalization was infrequent, with only seven
males and two females having been admitted to hospital during their lifetime. Of
these adolescents, five males and one female had only one treatment episode with
one discharge diagnosis. One male had three different discharge diagnoses within
one treatment episode and another had several long treatment episodes due to
autism, whereas one female had six discharge diagnoses within five inpatient
treatment periods. Self-poisoning was diagnosed in two males and one female.
Depression was diagnosed in one male and one female. Similarly, a substance
abuse diagnosis was given in the case of one male and one female. The remaining
discharge diagnoses were diverse and each occurred only once. Examples include
conduct disorder, adjustment disorder and eating disorder. Child psychiatric
diagnoses, such as autism and encopresis, were seen only among males.
59
The duration of previous psychiatric inpatient treatment periods varied from 1
day to 3 months (median 4 days, excluding one male subject with autism). Of
seven males with a history of psychiatric hospitalization, three had been
discharged within 6 months to 1 year before committing suicide, one within 1–2
years, and three more than two years before their suicide. One female subject was
on home leave from a psychiatric hospital at the time of her suicide, and another
had been discharged within 1–2 years before her suicide. Of the two females with
a history of admission to medical wards due to self-poisoning (i.e. a suicide
attempt), one had been discharged within 6 months and another within 1–2 years
before committing suicide. None of the adolescents with a history of lifetime
inpatient hospitalization due to mental disorder or self-poisoning were under the
age of 15 at the time of their deaths.
Mental disorder as a contributory cause of death
A psychiatric diagnosis, depression in all cases, was recorded on the death
certificates by the official medical examiners for four male and three female
suicides. Two males and two females had previously been hospitalized because of
a psychiatric disorder.
Previous suicidality and self-cutting
A significantly greater proportion of female than male adolescents (75% vs. 30%)
had shown evidence of previous suicidality, defined as the expression of suicidal
ideas or suicide attempts (Table 6). In a separate analysis of the expression of
suicidal ideas and previous suicide attempts, gender differences were shown to be
marginally significant. Significantly more of the female than male adolescents
had a history of self-cutting (33% of females vs. 7% of males).
Nonspecific symptoms of mental health problems
15% of the males and 8% of the females had shown nonspecific symptoms of
mental health problems, but did not have a history of inpatient hospitalization due
to a mental disorder or self-poisoning, previous suicidality, self-cutting, or a
mental disorder as a contributory cause of death. Information on nonspecific
symptoms of mental health problems was based on parental reports, which
described the recent behavioral and psychological characteristics of the
60
adolescent, for example signs of being depressed, withdrawn, nervous, or
uncommunicative. Evidence of mental health problems was also found in sources
such as the adolescents’ diary entries and suicide notes, revealing that they had
been contemplating suicide for a long period.
Other mental health related information
Information on the adolescents’ previous mental health treatment in outpatient
settings was rarely found among the documents establishing the cause of death. A
known history of outpatient psychiatric treatment was reported for only one male
and one female, and at the time of suicide, one female was currently receiving
such treatment.
Information concerning the mental health of the suicide victims was absent
for 24% of the males and 17% of the females. In 13% of the male suicides, the
documents stated explicitly that, according to parental reports (and in some cases
the primary care physician), the adolescent was physically and mentally healthy
and his behavior had been normal prior to the suicide. No precipitating events
were reported for these male adolescents. The method of suicide was firearm use
in all such cases, one of which involved a boy under 15 years of age.
5.2.4 Circumstances of the suicides (III, IV)
An adolescent’s home and its surroundings provided the most common location
for suicides among adolescents. A total of 59% (n=27) of the males and 50%
(n=6) of the females committed suicide in the home, in an outbuilding next to
their home, or outside in the near vicinity of their home (p=0.746). In terms of
suicide notes, 37% (n=17) of the males and 40% (n=5) of the females left a
written or recorded note (p=0.752). A precipitating event was reported in 24%
(n=11) of the males and 17% (n=2) of the females (p=0.716). The reported
precipitating events among males were an argument or the end of a relationship
with a girlfriend (45%, n=5), an argument with their parents (27%, n=3), an
argument with friends (9%, n=1), an argument with a girlfriend and friends (9%,
n=1) and shoplifting (9%, n=1). Among the females, the precipitating events were
an argument with friends in one case, and a recent abortion in another.
61
Seasonal pattern (IV) and time of suicides (III)
In the original publication IV, an analysis of seasonal variation was performed for
25 adolescent firearm suicides that had occurred in the province of Oulu in 1988–
2005. Adult (≥18 years) firearm suicides, n=554, committed in the province of
Oulu during the same time period were used as a comparison group. A significant
seasonal pattern (p<0.001) with a notable peak in the fall (ratio 2.70, 95% CI:
1.97–3.42) was found in adolescent firearm suicides (IV: Figure 1). 68% of these
firearm suicides occurred in the fall (August–October), 14% in the winter
(November–January), 21% in the spring (February–April) and none in the
summer (May–July). Among adults, however, firearm suicides peaked in the late
spring/early summer (p=0.05; ratio 1.19, 95% CI: 1.05–1.35). The seasonal
pattern of firearm suicides differed significantly between these two age groups
(p<0.001). In addition, the seasonal pattern of firearm suicides involving the
subgroup of young adults aged 18–23 years was similar to that of adult victims
(p=0.140).
By using updated data, this thesis presents unpublished results on adolescent
suicide seasonality by gender, up to the year 2012. Figure 3 shows the seasonal
distributions of adolescent male suicides within the updated data (1988–2012).
There was a significant fall peak (p=0.004; ratio 1.81, 95% CI 1.24–2.38) in all
male adolescent suicides, which was accounted for by the fall peak in firearm
suicides (p<0.001; ratio 2.60, 95% CI 1.91–3.29). In suicides by other methods,
there was a nonsignificant peak in the winter (p=0.188; ratio 1.87, 95% CI 0.93–
2.81). Very few male adolescent suicides were committed in the summer.
62
Fig. 3. Seasonal distribution of all suicides, firearm suicides and suicides by all other
methods among male adolescents in the province of Oulu, 1988–2012.
Due to the small number of female cases, the seasonal distribution of adolescent
female suicides was investigated for total data only. There was no discernible
seasonal pattern in the suicides of female adolescents, as 25% occurred in the
spring and 25% in the summer, 33% in the fall, and 17% in the winter (p=0.882).
In the original publication III, regarding the day of the week and time of day,
the exact time of death was known for 89% (n=41) of the male and 92% (n=11) of
the female adolescents (III: Figure 2). The variation in suicides in terms of days
of the week was rather small, with 48% of male suicides and 33% of female
suicides occurring on the weekends between Friday and Sunday. Among the
males, half of the suicides were committed during the day (between 06.00 and
18.00) and half at night (between 18.00 and 06.00) (III: Figure 2). Among the
females, one third of the suicides were committed in daytime and two thirds
during the night.
20%n=9
21%n=6
18%n=39%
n=4 0%n=0
24%n=4
46%n=21
66%n=19
47%n=2
26%n=12
14%n=4
47%n=8
0%
25%
50%
75%
100%
Adolescent males, all suicides(n=46)
Adolescent males, firearmsuicides (n=29)
Adolescent males, suicides byother methods (n=17)
Seasonal distribution of suicides (%)
Spring Summer Fall Winter
63
5.2.5 Toxicology findings (III)
Alcohol
48% (n=22) of the males and 58% (n=7) of the females were under the influence
of alcohol at the time of their suicide (p=0.747). Among the males, 11% (n=1) of
those under 15 years of age and 57% (n=21) of those aged 15–17 years were
under the influence of alcohol at their time of death (p=0.023). The corresponding
figures for the females were 0% and 70% (n=7) (p=0.152).
Blood alcohol concentration (BAC) data were available for 95% (n=21) of
the males and 100% (n=7) of the females. For the males, the mean (±SD; min–
max) BAC value was 1.34‰ (±0.47; 0.45–2.1) and for the females it was 1.19 ‰
(±0.52; 0.52–2.0) (p=0.476). Urine alcohol concentration (UAC) data
(unpublished results) were available for all of these adolescents. The mean UAC
value for the males was 1.96‰ (±0.72; 0.38–3.1) and for the females it was
1.71‰ (±0.64; 1.20–2.8) (p=0.419).
Figure 4 presents the UAC/BAC ratios of 21 male and 7 female adolescents
who were under the influence of alcohol at the time of suicide (unpublished
results). The reference line is the UAC/BAC ratio of 1.2, which indicates the
beginning of the post-absorptive phase of the BAC, i.e. descending blood alcohol
concentration. A total of 90% (n=19) of the males and 86% (n=6) of the females
were in the post-absorptive phase (UAC/BAC ratio >1.2) at the time of their
deaths. The mean (±SD; min–max) UAC/BAC ratio was 1.37 (±0.19; 0.79–1.59)
for the males and 1.45 (±0.37; 1.03–2.18) for the females (p=0.497).
64
Fig. 4. The UAC/BAC ratio of adolescents who were under the influence of alcohol at
the time of their suicide, by gender.
Males who committed suicide during the night were significantly more often
under the influence of alcohol at their time of death than males who committed
suicide in the daytime (86% (18/21) vs. 15% (3/20), p<0.001) (III: Figure 2).
Among females, 86% (6/7) of those who committed suicide at night were under
the influence of alcohol, compared with 25% (1/4) of those who committed
suicide during the day, and a trend towards statistical significance was found
(p=0.088).
Substances other than alcohol
Toxicology screens for substances other than alcohol had been performed for 79%
(n=33) of the 42 males for whom information on toxicological investigations was
available and for 92% (n=11) of the females. Among them, 21% (7/33) of the
males and 36% (4/11) of the females tested positive for the presence of illegal or
65
prescription drugs. Among the females, a drug overdose was the method of
suicide in two such deaths. The specific substances found in the toxicology
screens are shown in Table 7. Benzodiazepines and benzodiazepine-like drugs
(diazepam, temazepam, unspecified benzodiazepine and zolpidem) and
antidepressants (mianserin, doxepin, mirtazapine and paroxetine) were the most
commonly detected prescription drugs. Antidepressants had been prescribed for
the two females who screened positive for such medication, but in other cases
there was no indication that the drugs had been prescribed for the adolescents.
Cannabis was found in one male. No positive results were found in cases where
subjects were tested for the presence of so-called hard drugs such as
amphetamine, cocaine or buprenorphine. Four males and three females were also
under the influence of alcohol at the time of death. None of the adolescents who
tested positive for the presence of illegal or prescription drugs were under 15
years of age at the time of their death.
Table 7. Substances other than alcohol detected in the blood or urine of adolescent
suicide victims.
Cases Substances in blood Substances in urine
Males
Alcohol present
Case 1 diazepam 1
Case 2 zolpidem 1
Case 3 benzodiazepine (unspecified)
Case 4 codein, salicylates
No alcohol present
Case 1 mianserin 1
Case 2 methyl tert-butyl ether 1 2 doxepin
Case 3 cannabis 1 3 cannabis 1 3
Females
Alcohol present
Case 1 mirtazapine, ibuprofen
Case 2 temazepam temazepam
Case 3 4 codein, paracetamol, ibuprofen codein, paracetamol, ibuprofen
No alcohol present
Case 1 4 paroxetine, levomepromazine 1 Recorded as contributing cause of death in death certificate. 2 Had drunk gasoline. 3 Also detected in hair. 4 Drug overdose as a method of suicide.
66
5.2.6 Somatic findings from the medicolegal autopsies (III)
Below are presented unpublished findings, based on data from external and
internal examinations and microscopic examinations conducted during the
medicolegal autopsies of adolescent suicide victims. In relation to the somatic
diseases observed during the autopsies, there were early signs of atherosclerosis
in 33% (n=15) of the males and in 25% (n=3) of the females, mild fatty
degeneration of the liver in three cases, one case of gastritis, one case of mild
pneumonia, and one case of thyroid cancer.
Information on the body mass index (BMI) was available for 89% (n=41) of
the males and 100% (n=12) of the females. The average BMI was 22.7 kg/m2 for
the males and 21.2 kg/m2 for the females. 13% (n=6) of the males and none of the
females were overweight or obese (BMI >25 kg/m2). 2% (n=1) of the males and
8% (n=1) of the females were underweight (BMI <18.5 kg/m2).
Of the three males with self-cutting scars, the scars were located on the thighs
in the case of two males and the thighs and arms in the case of one male. Among
females, the location of the scars was the arms for all four suicide victims.
67
6 Discussion
6.1 Overview of the results
Following the continuously increasing trend in male adolescent suicides in
Finland from the late 1960s onwards, rates began to decline after the early 1990s.
However, this favorable development has not continued in recent years, as slight
increases in suicide rates have been observed among male adolescents. Among
adolescent females, following earlier inconsistent trends suicide rates began to
increase in the early 1990s. This alarming upward trend was followed by a
slightly decreasing trend from the early 2000s.
From the 1970s, use of firearms was the most common suicide method
among Finnish male adolescents, until traffic suicides took the lead position in
recent years. Among females, poisoning used to be the most common suicide
method before 1990, but hanging surpassed poisoning after that time. In line with
the situation for males, traffic suicides have recently exceeded hanging to become
the most common method of suicide among female adolescents. On a more
general level, there has been a decrease in the use of all violent methods among
males, and an increase for females since the early 1990s.
Between the years 1972–2009, the adolescent male firearm suicide rate in
Northern Finland was almost three times higher than that observed in Southern
Finland, while there was no difference in rates of suicide by other methods. A
northern excess in firearm suicide rates was also found among young adult and
adult males. Hunting guns were the most common type of firearms employed in
the case of young male suicides, and their use was particularly common in
Northern Finland.
In a comprehensive sample of adolescent suicides that occurred in the
province of Oulu during a period of 25 years, only a minority of the suicide
victims had a previous history of psychiatric hospitalization. The discharge
diagnoses were heterogeneous. A higher proportion of females than males had a
known history of previous suicidality. Half of the adolescents were under the
influence of alcohol at the time of death. Of these, the vast majority committed
suicide during the night and during the descending phase of the blood alcohol
concentration. One fifth of adolescents screened positive for substances other than
alcohol. Violent methods of suicide predominated (males 98%, females 83%).
Use of firearms was the most common suicide method among both genders. A
68
significant seasonal pattern was discernible among male adolescent firearm
suicides, with a peak occurring in the fall.
6.2 Discussion of the findings
6.2.1 Trends in child and adolescent suicides (I)
The results of the study of trends in the suicide rates of Finnish adolescents aged
less than 18 years showed that male adolescent suicide rates increased from 1969
to 1989, while there were no consistent changes in the rates for adolescent
females during that period. The transition from the 1980s to the 1990s marked a
turning point in adolescent suicides, since from that time onwards the adolescent
male suicide rate began to decline, while the female suicide rate followed an
upward trend. It is worth noting that more recent data up to the year 2012 again
revealed shifts in suicide trends among both genders. The previous favorable
decline in male adolescent suicides gave way to a slight increase in the mid-
2000s, while the previous increase in female adolescent suicide rates has ceased
and a slightly declining trend has emerged since the early 2000s. However,
despite these trend changes, current male adolescent suicide rates are still
remarkably lower, and the corresponding rates in females higher, compared to the
rates in the early 1990s.
The general decreasing trend in suicide rates among adolescent males from
the 1990s is in line with the decline reported in the general Finnish male
population, whose suicide rate fell by half between 1990 and 2012. Whereas the
rate was as high as 50.1 per 100,000 male population in 1990, it had fallen to 23.6
by 2012 (Statistics Finland 2014a). As regards females in the general population,
a declining suicide trend has also been observed in their rates of suicide between
1990 and 2012 (from 12.1 to 7.5 per 100,000 population). Therefore, during the
1990s the rising suicide trend among adolescent females was the opposite to that
among Finland’s general female population.
It is remarkable that, despite the long history of suicide research, explanations
of changing trends in suicide rates have remained largely speculative. In Finland,
it has been suggested that decreasing suicide rates among the general Finnish
population are related to better depression treatments, with special regard being
paid to the increased use of SSRI antidepressants (Korkeila et al. 2007, Lönnqvist
2009, Partonen 2012). In addition, the multidimensional effects of the national
69
suicide prevention project in Finland, established in the late 1980s (Lönnqvist et al. 1993), and positive advances in society in a broader sense, have been proposed
as possible contributors to this decreasing trend (Hiltunen et al. 2009, Lönnqvist
2007). With regard to the use of adolescent outpatient psychiatric services in
Finland, the number of 13–22-year-old patients has increased by two thirds in the
2000s and it has been suggested that the previously hidden need for psychiatric
services has given way to active demand (Pylkkänen 2013). Also researchers
from various other countries have suggested that improvements in antidepressant
treatment and government suicide prevention strategies may underlie decreasing
suicide rates among young people (Bridge et al. 2005, McKeown et al. 2006,
Morrell et al. 2007). Other authors seeking explanations for changes in adolescent
suicide rates have focused on factors such as rates of alcohol consumption, access
to lethal means and the influence of the internet (Biddle et al. 2008, Brent et al. 1987, Bridge et al. 2008, McClure 2001). On the other hand, it has been
suggested that a combination of socio-economic and clinical factors accounts for
the changes (Windfuhr et al. 2008), which is consistent with the view that suicide
is a multidetermined event.
Better treatment of depression and the favorable societal changes that have
occurred in Finland may play a role in explaining the decrease in adolescent male
suicides since 1990, but the important question arises of why the rate for
adolescent females has followed the opposite trend at the same time. Notably, the
increase has specifically occurred in the rates (and proportion) of violent suicide
methods, whereas the rate of non-violent methods has remained unchanged.
Similarly to the present findings, a shift towards the use of more violent suicide
methods among young (20–24 years) females had been observed in Finland
before the 1990s (Öhberg et al. 1996), and more recently in several other
European countries (Värnik et al. 2009). It has been suggested that converging
gender roles, i.e. as more similar roles have begun to replace traditional
masculine/feminine roles, are contributing to this phenomenon (Grøholt et al. 1999, Pompili et al. 2009, Värnik et al. 2009). This is alarming, since females are
known to have higher rates of attempted suicide than males and the use of violent
suicide methods is more likely to end in a fatal outcome.
It is also of interest to compare the distributions of violent and non-violent
suicide methods among Finnish adolescents to those among the adult population
in Finland. Between 1998 and 2012, violent methods were employed in 76% of
male and 46% of female adult (≥25 years) suicides (Statistics Finland 2014a),
which illustrates the traditional gender difference in the choice of violent and non-
70
violent methods among adult suicide victims. As the results of the present study
show, the proportions of violent suicide methods among adolescents of both
genders are notably higher than the corresponding proportions for adults.
Correspondingly, Hepp et al. (2012) have reported that suicides by intoxication
are less frequent among Swiss adolescents than among adults. They suggest that
this may be due to adolescents having more difficulty accessing potentially lethal
drugs and lacking sufficient knowledge of the toxicity and lethal doses involved.
Apart from considerations of method availability, another possible explanation for
the large proportion of violent suicide methods among adolescents is related to
the sociocultural acceptability of different suicide methods, with norms and
traditions having an effect on the choice of suicide method (Cantor & Baume
1998).
Recent changes in the types of suicide methods among adolescents in Finland
also merit consideration. Use of firearms has been the predominant method for
Finnish adolescent males – accounting for half of all suicides – since at least the
1970s. The most recent suicide statistics from the years 2008–2012 showed,
however, that traffic suicides have overtaken the use of firearms and hanging
to become the leading suicide method among male adolescents. Similarly, traffic
suicides have assumed the leading position in suicide methods among adolescent
females and the shift towards the increasing use of this method had already begun
among females in the 1990s. Again, this suggests that sociocultural acceptability
may be of importance to the choice of method and that traditional patterns of
suicide among adolescents are subject to change.
6.2.2 Regional differences in child and adolescent male firearm suicides (II)
The results of this study demonstrated a marked regional difference in firearm
suicide rates among adolescent males, with significantly higher rates in Northern
Finland compared to Southern Finland. By contrast, rates of suicide by all other
methods did not show such a regional difference. Use of firearms evidently
accounts for a major part of the northern excess in suicide rates among Finnish
male adolescents.
In Finland, particularly in the northern areas of the country, hunting is a
traditional sport among males of all age groups, including young adolescents. The
prevalence of firearms in general, and hunting guns in particular, is substantially
higher in Northern Finland compared to Southern Finland (The Finnish Police,
71
unpublished data). The association between a greater number of firearms and
higher rate of firearm suicides within any specific region has been demonstrated
in several studies (Ajdacic-Gross et al. 2010b, Johnson et al. 2000, Miller et al. 2007). The results of the present study showed that a regional difference in rates
of firearm suicide was present among all <45-year-old Finnish males, but that the
difference in rates was more prominent among adolescent and young adult males
(2.8- and 2.6-fold differences, respectively) than in adult males (1.9-fold
difference). Earlier studies have reported that the association between greater
availability of firearms and higher rates of firearm suicides is more evident in
young people than adult populations (Birckmayer & Hemenway 2001, Sloan et al. 1990). It has been suggested that this is because young persons are more
impulsive. This impulsiveness when combined with easy access to a highly lethal
method then leads to greater susceptibility to suicide among younger people,
compared to older people (Miller et al. 2007).
With regard to suicide prevention, the evidence strongly suggests that means
restriction is among the most effective available policies (Mann et al. 2005, Yip et al. 2012). Correspondingly, stricter firearm control as a means of suicide
prevention has been emphasized in Finland (Wahlbeck 2011). Finland actually
implemented stricter firearms legislation back in 1998 and again in 2011
(Firearms Act 1998), and a legislative proposal has very recently been presented
to the Finnish Parliament proposing the further restriction of e.g. firearm storage
practices (HE 20/2014). Further, from 2011 physicians have been duty-bound to
notify the police of any persons they consider unfit to possess a firearm on the
basis of the person’s health or behavior, as stated in amendment 11.2.2011/124 of
the Firearms Act (1998). Physicians’ duty to notify the police is further specified
in the ongoing legislative proposal (HE 20/2014). Those opposed to means
restriction strategies argue that, according to the substitution hypothesis, if one
method of suicide becomes unavailable, a suicidal person will seek an alternative
method. However, it has been suggested that individuals have a preference for a
specific means of suicide, which makes method substitution unlikely (Daigle
2005). To conclude, the findings of this study underscore the importance of
further research on relations between firearm availability and suicide, and
adolescents should be included in these studies.
72
6.2.3 Characteristics of child and adolescent suicides in the province of Oulu (III, IV)
Various characteristics of adolescent suicides were scrutinized in order to broaden
the understanding of what may lie behind suicides among adolescents from the
province of Oulu in Northern Finland. The basic demographic characteristics of
adolescent suicide victims in this case series study are in line with previous
research, as the number of male suicides was almost four times that of females,
and suicide rates increased with age among both genders. Violent methods of
suicide were almost always used (in 98% of cases) by adolescent males, and also
predominated among females (83%); this is in accordance with the distribution of
violent and non-violent suicide methods among Finnish adolescents in the country
as a whole. The present study reveals that use of firearms was the most common
method of suicide among both genders. This contrasts with the method
distribution among adolescent females in the whole of Finland, since less than
10% of these suicides were committed using firearms during 1990–2008. As
discussed earlier, cultural factors may play a role in the choice of specific suicide
methods, which may also be of importance in explaining the present finding on
the relatively greater use of firearms among adolescent females in the province of
Oulu.
A minority of the suicide victims (15% of males and 17% of females) had a
lifetime history of psychiatric inpatient hospitalization, which coheres with
previous findings based on international studies. Brent et al. (1999) reported that
15% of adolescent suicide victims had received inpatient care, and other
researchers have reported figures as low as between 2–5% (Grøholt et al. 1997,
Portzky et al. 2005). The figures reported for lifetime mental health care contacts
among adolescent suicide victims have varied between 20 and 50% (Grøholt et al. 1999, Karch et al. 2013, Marttunen et al. 1992, Portzky et al. 2005, Shaffer et al. 1996). In the present study, explicit information on psychiatric outpatient
treatment was scarce. Only one male and two females were known to have
received such care in their lifetimes. However, the clinical impression which
emerged based on all of the available information suggested that the majority of
the adolescent suicide victims had never been in contact with mental health
services. Current psychiatric treatment (at the time of death of the adolescent) was
also rare in this study, again a finding consistent with previous studies (Brent et al. 1988, Grøholt et al. 1997, Rich et al. 1990, Shafii et al. 1988, Windfuhr et al. 2008).
73
The infrequency of psychiatric care among adolescent suicide victims may
have several explanations. Outward signs of mental health problems among
adolescents may not be sufficiently severe to be recognized by others, and the
adolescents may conceal or deny the extent of their problems. Further, even
where problems are recognized, there may be reluctance on the part of the family,
friends and the adolescents themselves to seek help from health care
professionals, possibly due to the stigma associated with mental illness (Moskos
et al. 2007). Young people’s reluctance to seek professional help for mental health
problems is a well-known phenomenon and applies to young males in particular
(Rickwood et al. 2007).
It is also possible that some of these adolescents had no need of psychiatric
care since mental health problems were not involved. Based on the parental
reports, 13% of the male adolescents covered in this study had been healthy,
normally behaving adolescents whose suicides were completely unexpected. This
finding seems consistent with the results of psychological autopsy studies, which
have reported that approximately 10% of adolescent suicide victims (usually
male) had no diagnosable psychiatric disorder (Brent et al. 1993a, Marttunen et al. 1991, Renaud et al. 2008, Shaffer et al. 1996). Suicides of this kind have often
been explained in terms of impulsiveness. However, Brent et al. (1993b) found
that adolescent suicide victims without an apparent psychiatric disorder were
more likely to have some psychiatric risk factors, such as familial psychiatric
disorders, compared to community controls. With regard to the present study, data
on the mental health characteristics of the adolescents in question lacked
sufficient detail for firm conclusions to be drawn in this respect.
In the present study, 25% of the females and just 4% of males were known to
have previously attempted suicide, or the reverse, with 75% of the females and
96% of the males having died in their first suicide attempt. Previous studies have
shown that a prior suicide attempt is a key risk factor in completed suicides
among adolescents of both genders (Brent et al. 1999, Grøholt et al. 1997, Shaffer
et al. 1996). However, in the current study a history of previous suicide attempt(s)
seemed to serve as a potential predictor of suicide among females, but not among
males.
The results of the present study showed that self-cutting scars were much
more prevalent in adolescent female than male suicide victims (33% vs. 7%).
Compared with these results, the life-time prevalence of self-cutting amongst the
general Finnish adolescent population aged between 13 and 18 years is lower
(17%) for females and the same (7%) among males (Laukkanen et al. 2009).
74
From a predictive viewpoint, self-cutting may therefore be an indicator of a
potential suicide risk among female, but not male, adolescents. On the other hand,
Laukkanen et al. (2013) have shown that adolescents who cut themselves on parts
of the body other than just the arms present with psychiatric problems of greater
severity, such as being more likely to have suicidal thoughts and attempt suicide,
than those with self-cutting on the arms alone. Interestingly, in the present study
self-cutting scars were located only on the arms among all four females, while all
three males had cut themselves on the thighs (and also on the arms in one case).
In the normal population study by Laukkanen et al. (2013) 11% of male
adolescents who had a history of self-cutting had cut themselves on parts of the
body other than the arms, compared with 100% of male suicide victims with self-
cutting in the present study. The question therefore remains whether the location
of self-cutting elsewhere than only in the arms serves as an indicator of suicide
risk among male adolescents.
It is of great importance that this study found that 48% of male and 58% of
female adolescent suicide victims had committed suicide while under the
influence of alcohol. These figures, especially with respect to females, are notably
high compared to findings from other countries. In the US, approximately 20–
30% of adolescent male and 10–15% of adolescent female suicide victims were
intoxicated with alcohol at their time of death (Brent et al. 1999, Singh & Lathrop
2008). The corresponding figures were approximately 45% and 40% in Norway
(Grøholt et al. 1999) and 40% and 20% in Sweden (Johansson et al. 2005).
Compared with previous findings from Finland, in agreement with the present
results a study by Marttunen et al. (1992) reported that 50% of male and 56% of
female adolescents had been intoxicated at the time of suicide. However, a recent
report on all deaths among Finnish children in 2009–2011 found a substantially
lower proportion, 25%, of intoxicated <18 year-old suicide victims
(Onnettomuustutkintakeskus 2014). No gender-specific results were presented.
An intriguing finding arising from the present study concerns the stage of
alcohol metabolism among intoxicated adolescent suicides. Alcohol has a well-
known biphasic effect: stimulation and elation are typical of the phase during
which the level of blood alcohol concentration (BAC) is still increasing, whereas
sedation and feelings of depression characterize the declining phase of the BAC
(Jung 2009). In the present study, most intoxicated suicide victims were in the
declining phase of BAC at the time of death. Similar findings have been reported
in studies on adult suicides (Hayward et al. 1992, James 1966), with the majority
of suicide victims having died during the descending phase of BAC. Both studies
75
concluded that acute alcohol use seems to lower the threshold for suicidal
behavior, probably through its depressant and disinhibiting effects, rather than
functioning as “Dutch courage” (i.e. first deciding to commit suicide and then
drinking alcohol to gain sufficient determination to complete the act). The current
study also found that being under the influence of alcohol was related to
committing suicide at night. Whereas 86% of both male and female adolescents
who committed suicide during the night were intoxicated, in the daytime the
proportion of suicides committed while under the influence of alcohol was only
15% among males and 25% among females. It may be that tiredness-related
adverse psychological changes, such as loss of inhibitions and impairment of
judgment, further intensify the similar adverse effects of acute alcohol use –
especially during the BAC’s descending phase, when the depressant action of
alcohol prevails.
The results of toxicological analyses revealed that, with regard to substances
other than alcohol, only one suicide victim tested positive for cannabis. No
positive findings presented in cases where so-called hard drugs, such as
amphetamine and cocaine, were tested. Prescription drugs were detected in just
under one fifth of the cases in which toxicology screens had been performed,
excluding victims who had used drug overdose as the method of suicide. The
most commonly detected drugs were anxiolytes. With two exceptions (two
females taking antidepressants), there was no indication that the prescription
drugs detected had been prescribed to the adolescents, so these drugs seemed to
have been used for intoxication purposes.
Unfortunately, no information on previous alcohol or drug use patterns
among the adolescent suicide victims was available within the study data. This
precluded an elucidation of the possible role played by more chronic substance
abuse. Previously, Pirkola et al. (1999) have shown that, compared with other
adolescent suicide victims, Finnish adolescent (13–22 years) suicide victims who
misuse alcohol suffered from more severe and long-standing psychiatric
morbidity. They also had a greater tendency to be intoxicated at the time of
suicide.
Analysis of seasonal distributions in adolescent suicides revealed a
noteworthy finding of the present study, i.e. that male adolescent firearm suicides
show a peak incidence in the fall. The seasonal pattern was remarkably different
to that in the adult population, which showed a traditional spring/early summer
peak. It was of note that the seasonal pattern of firearm suicides among young
adults (18–23 years) was similar to that observed in other adults, which indicates
76
that the fall peak is a specific phenomenon among the youngest age group. Other
authors who have observed a fall peak in young people’s suicides have suggested
that the intensification of social life after the summer vacations exposes young
people to stressful situations and increases the risk of suicide (Chew & McCleary
1994, Näyhä 1982, Shields et al. 2006). Notably, in the present study the fall peak
was found only in firearm suicides among adolescent males, whereas no specific
pattern could be found among suicides by all other methods among males and all
methods among females. This suggests that firearms play a specific role in
explaining the seasonal distribution. One explanation for this may be easy access
to hunting guns in homes in the fall, due to the beginning of the hunting season.
6.3 Strengths and limitations
6.3.1 Strengths of the study
The national register of causes of death, from which the data for the macro-level
studies in this thesis were drawn, has proven a reliable source of information for
scientific purposes (Lahti & Penttilä 2001). In Finland, the effort is to apply
methods of medicolegal death investigation in all cases in which the cause of
death may be other than a disease, and therefore the proportion of autopsies is
high among such cases (Ministry of Social Affairs and Health 2007). Overall, the
rate of medicolegal autopsies is high in this country. For example, in the year
2012 a medicolegal autopsy was performed in 19% of all deaths (Statistics
Finland 2014a). Further, the suicide statistics cover the entire country with equal
reliability. It is unlikely that determination of death as suicide differs between
medical examiners from different regions.
The study sample in micro-level studies was comprehensive, including all
consecutive child and adolescent suicides committed in the province of Oulu
during the 25 study years. The completeness and accuracy of the nationwide
health register (FHDR), which was used as one source of information, is generally
good (Sund 2012). Information collected from FHDR and the death certificates
was systematically available for all adolescent suicide victims. In addition, police
investigation reports, findings from external and internal examinations of the
medicolegal autopsies, and the final medicolegal autopsy reports were
systematically present in all 93% of cases in which the suicide case files were
77
available. Blood alcohol concentrations had been investigated in all cases and
other toxicological examinations had been performed in most.
6.3.2 Limitations of the study
A number of limitations in this study should be acknowledged. Regarding macro-
level studies, as the data consist of suicide counts, it was not possible to analyze
any biopsychosocial factors, such as the psychiatric histories of individual
victims. Some suicides may have been misclassified as accidental or
undetermined deaths (Öhberg & Lönnqvist 1998). However, the proportion of
undetermined deaths has remained stable and it is unlikely that changes in suicide
rates can be attributed to misclassification (Chishti et al. 2003).
In the micro-level studies involved in this thesis, the documents used to
obtain the data were not compiled for research purposes, but in order to establish
the cause of death. Information was not therefore systematically and consistently
available on every variable in every case. In particular, information on psychiatric
symptoms and mental health status recorded in the documents was either scarce
or had simply not been documented in any form. Conclusions on this issue must
therefore be drawn with great caution. Furthermore, unlike psychological autopsy
studies, record review studies such as the present one do not allow for psychiatric
diagnostic assessment. Gender comparisons may be biased and underpowered due
to missing data. Although all self-cutting scars identified in external examinations
were reported, in some cases there may have been a history of superficial self-
cutting which leaves no permanent scarring on the skin. When seeking potential
predictors for suicide, case-control design would allow the calculation of the
suicide risk in relation to the various background and clinical characteristics of
suicide victims. However, no meaningful controls were available for the purposes
of this study.
The small numbers of cases may have caused a lack of statistical power in the
analyses of subgroups, particularly in the micro-level studies. Some potential
findings may therefore have remained statistically non-significant (type II error).
Although the main findings are statistically robust, several comparisons have
been performed and the risk of spurious findings (i.e. type I errors) cannot be
discounted.
78
79
7 Conclusions
7.1 Main conclusions
Both favorable and unfavorable changes have occurred in suicide rates among
children and adolescents in Finland, with those of males decreasing since the
beginning of 1990s, while rates among females have increased. Although
indications of opposite trends have been observed more recently in both genders,
on a general level rates of male suicides are still lower, and those of females
higher, than they used to be two decades ago. The Finnish male adolescent suicide
rate was higher than that of females throughout the 44-year study period covered
in this research. However, the gender difference in overall suicide rates has
narrowed following the changes in suicide rates.
Finnish female adolescents now have a greater tendency to choose a violent
suicide method. The increase in overall suicide rates among female adolescents
stems specifically from the increase in violent methods of suicide, the rate of
nonviolent methods having remained unchanged. This phenomenon is of
particular concern, as females are known to make a large number of suicide
attempts, and the use of violent suicide methods is more likely to end in death.
With further regard to suicide methods, use of firearms has predominated among
Finnish adolescent males since the 1970s. In female adolescents, hanging has
exceeded poisoning as the leading method of suicide since 1990. In recent years,
however, traffic suicides have taken the leading position as the most common
method of suicide for both genders, which may indicate that the sociocultural
acceptability of this method of suicide has increased among Finland’s young
population.
Between 1972–2009, the adolescent male firearm suicide rate was almost
three times higher in Northern Finland than in Southern Finland, while no such
regional difference appeared in rates of suicide by all other methods. This
suggests that, compared with Southern Finland, use of firearms plays a major role
in explaining the higher male child and adolescent suicide rate in Northern
Finland. Although a causal relationship cannot be inferred from this, it is
proposed that the greater prevalence of firearms in Northern Finland compared to
Southern Finland is a contributing factor.
As regards the similarities and differences in adolescent male and female
suicides, apart from those observed in the rates and methods of suicide, the
80
empirically based study from the province of Oulu investigated more specific
characteristics associated with the suicide victims. Regardless of gender, evidence
of mental health problems was common, but only a minority had a history of
psychiatric hospitalization. Previous suicidality and self-cutting were more
common in female than male adolescents. Whereas being under the influence of
alcohol at the time of death was infrequent among child and young adolescent
suicide victims, more than half of the 15–17-year-old male and female
adolescents had been intoxicated with alcohol at the time of their death, which
highlights the role of acute alcohol use in adolescent suicides in both genders.
Most of the intoxicated adolescents were in the descending phase of blood alcohol
concentration at the time of their suicide, which suggests that the depressant
effect of alcohol use may have contributed to the decision to commit suicide. This
study also found that two thirds of all adolescent male firearm suicides were
committed between August and October, indicating that the fall is a high-risk
period for such suicides.
7.2 Implications of the study
The general upward trend in Finnish female adolescent suicide rates warrants
attention. As suicide is a multifactorial process, no conclusive explanations can be
offered for the changes in suicide trends, but the increase in violent methods of
suicide seems to contribute to the phenomenon. In terms of suicide prevention
efforts, method restriction is considered one of the most effective preventive
strategies. The predominance of hanging suicides and, in recent times, traffic
suicides in particular, impose limitations on the potential for employing the
method restriction strategy, since both of these methods are difficult to restrict.
The rate of adolescent male firearm suicides was substantially higher in
Northern than Southern Finland. Another special characteristic of firearm suicides
among adolescent males in Northern Finland was the notable seasonal pattern,
with a peak incidence of firearm suicides occurring in the fall. These findings
emphasize the need to develop suicide prevention in line with specific regional
characteristics.
Acute alcohol use was shown to play a central role in adolescent suicides,
regardless of gender. Although no information on patterns of previous alcohol use
among adolescents was available for the present study, previous research has
shown that alcohol abuse is an important risk factor in adolescent suicide.
81
Reducing alcohol use and drunkenness-oriented drinking among underage
adolescents is highly important from a preventative viewpoint.
Psychiatric disorders are thought to be present in the majority of adolescent
suicides, but these disorders have often gone unrecognized and untreated. Many
adolescents, especially males, tend not to seek help for their mental health
problems. However, the role of health care professionals in suicide prevention
(most importantly, identifying and treating psychiatric disorders) is limited to
individuals who come into contact with health services. The role of family,
friends, and other close people can therefore be vital in recognizing possible signs
of distress in adolescents. Nevertheless, when an adolescent presents to the health
care system and his or her general health is being evaluated, consideration should
always be taken of the patient’s mental health status. Finally, functioning, low-
threshold mental health services providing easy access to care, preferably
integrated with the school health care system, and a reduction in the stigma
associated with mental health problems, could be helpful in encouraging
vulnerable children and adolescents to seek and obtain help.
7.3 Implications for further research
This epidemiological study on the trends and characteristics of suicide among
children and adolescents in Finland provides the following insights for future
research. Firstly, the increased use of violent suicide methods among female
adolescents is alarming. Further studies are needed in order to investigate the
possible underlying factors at individual level and to explore whether the
phenomenon is universal amongst this young age group. Secondly, studies on the
seasonality of child and adolescent suicides are rare and the findings are
heterogeneous. Additional studies are therefore needed, which should also take
account of the effect of biopsychosocial factors in order to identify their putative
influences on seasonal variations in suicides. Thirdly, it remains to be seen
whether the novel finding on the descending phase of blood alcohol
concentrations at the time of suicide among children and adolescents can be
confirmed in future studies.
82
83
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Appendix 1. The Finnish death certificate form
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Original publications
I Lahti A, Räsänen P, Riala K, Keränen S & Hakko H (2011) Youth suicide trends in Finland, 1969–2008. Journal of Child Psychology and Psychiatry 52: 984–991.
II Lahti A, Keränen S, Hakko H, Riala K & Räsänen P (2014) Northern excess in adolescent male firearm suicides: A register-based regional study from Finland, 1972–2009. European Child & Adolescent Psychiatry 23: 45–52.
III Lahti A, Harju A, Hakko H, Riala K & Räsänen P (2014) Suicide in children and young adolescents: A 25-year database on suicides from Northern Finland. Journal of Psychiatric Research 58: 123–128.
IV Lahti A, Räsänen P, Karvonen K, Särkioja T, Meyer-Rochow VB & Hakko H (2006) Autumn peak in shooting suicides of children and adolescents from Northern Finland. Neuropsychobiology 54: 140–146.
Reprinted with the permission of John Wiley and Sons (I), Springer (II), Elsevier
(III) and Karger (IV).
The original articles are not included in the electronic version of the thesis.
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EPIDEMIOLOGICAL STUDYON TRENDS AND CHARACTERISTICS OF SUICIDE AMONG CHILDREN AND ADOLESCENTS IN FINLAND
UNIVERSITY OF OULU GRADUATE SCHOOL;UNIVERSITY OF OULU, FACULTY OF MEDICINE,INSTITUTE OF CLINICAL MEDICINE, DEPARTMENT OF PSYCHIATRY;OULU UNIVERSITY HOSPITAL, DEPARTMENT OF PSYCHIATRY;HELSINKI UNIVERSITY CENTRAL HOSPITAL,DEPARTMENT OF PSYCHIATRY, DIVISION OF ADOLESCENT PSYCHIATRY