Journal of Substance Use, 2013; 18(4): 302–310

RESEARCH ARTICLE

Comparison of self-report and biological measuresfor alcohol, tobacco and illicit drug use in consecutivealcohol-dependent patients visiting a tertiary care centre

RAKA JAIN1, RIZWANA QURAISHI1, PRADIPTA MAJUMDER2, & RAMANDEEP PATTANAYAK2

1National Drug Dependence Treatment Centre, All India Institute of Medical Sciences, New Delhi, India,2Department of Psychiatry, All India Institute of Medical Sciences, New Delhi, India

AbstractBackground: Alcohol is a major drug of abuse in patients visiting treatment centres. The self-report isused by clinicians to collect information; however, alcohol-dependent patients may not provide reliableself-reports.Aim: The study aimed to assess the agreement between urinalysis and self-report for licit and illicit druguse in alcohol-dependent patients and to examine the relationship of biochemical measures with self-reported alcohol consumption.Methods: Consecutive patients (N ¼ 199) with current alcohol use fulfilling Diagnostic and StatisticalManual, 4th edition (DSM-IV) criteria for alcohol dependence were included. Recent alcohol and druguse was enquired using a structured questionnaire. The biological measures included urine druganalysis and biochemical liver function tests.Results: Urinalysis revealed the use of opiates, cannabis, nicotine and benzodiazepines in 2.5%, 4.2%,5.9% and 28.8%, respectively, even though patients reported no use of these drugs. Gamma-glutamyltransferase (GGT) was elevated in 95.2% of patients with self-reported heavy alcohol consumption,whereas it was raised in 60–62.5% of those with low to moderate alcohol use. In heavy drinkers, thebiochemical liver markers appeared to corroborate with self-reported alcohol use.Conclusion: This study urges for the use of objective methods to validate the self-report in alcohol-dependent patients, especially for co-occurring nonprescription benzodiazepine and drug use.

Keywords: Self-report, alcohol dependence, urinalysis, biochemical markers

Introduction

Alcoholism represents a serious health issue with major socio-economic consequences(Murray & Lopez, 1997). Nearly 21% of adult Indian males are current users of alcohol, ofwhich 17–26% are dependent users. Alcohol is the primary drug of abuse in 43.9% of patients

Correspondence: Raka Jain, National Drug Dependence Treatment Centre, All India Institute of Medical Sciences, New Delhi110029, India. E-mail: rakajain2009@gmail.com

ISSN 1465-9891 print/1475-9942 online © 2013 Informa UK Ltd.DOI: 10.3109/14659891.2012.674625

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visiting substance use treatment settings in India (Ray et al., 2004). However, it has beenfound that physicians are likely to identify only 20–50% of patients with alcoholism who areattending medical care (Sharpe, 2001).

Clinicians working with alcohol-dependent patients often have to rely on self-report for anylicit or illicit drug use other than alcohol. Many a times, even family members are not awareabout the precise nature of various drugs consumed by the patients. However, the substance-using patients are likely to under-report, misreport or hold back some information regardingdrug usage (Hser, 1997; Jain, 2004; Chen et al., 2006). There can be several possible reasonsfor withholding such information: the patient (a) may not perceive the use of drugs other thanalcohol to be physically harmful or requiring an intervention by a doctor, (b) may perceivemore control over use of other drugs compared to alcohol or (c) may simply be ashamed ofaccepting multiple drugs of abuse. Besides other drugs, many people tend not to report theiralcohol intake correctly, but rather deny drinking or at least under-report the true amount(Midanik, 1989; Helander et al., 1999). Moreover, chronic alcohol use is often associatedwith memory or cognitive impairments which may further contribute to unreliable self-report. Certain personality traits associated with addictive behaviours may facilitate easylying and manipulation. Hence, obtaining reliable information about a person’s drinkinghabits is also a difficult task (Jain, 2004). The clinician should be aware of the nature of otherdrugs consumed by alcohol-dependent patients in order to provide a safe and effectivemanagement. There is a need to ascertain the validity of self-reported drug use in alcohol-dependent patients by comparing it with objective measures.

Among the western studies that have examined the validity of self-reported drug use againsturinalysis, 25 –72% of subjects whose urine tested positive denied any recent use of drugs(Maisto et al., 1990; Hser, 1997). As many as two-thirds of the patients in an emergencysetting inaccurately denied illicit drug use as revealed by urinalysis (Chen et al., 2006). Thevalidity of self-reports of recent drug use may differ according to a number of factors such asthe type of setting and the nature of substance used. Available Indian studies have generallyshown moderate concordance rates between self-report and urinalysis, with both under- andover-reporting of drug use. The agreement between self-report and urinalysis was found to beespecially poor for opioids (Jain, 2004; Jain et al., 2006).

The biochemical liver function tests can detect the deleterious effects of alcohol on thehepatic system and may serve as a biomarker of excessive drinking as well as alcoholic liverdisease (ALD; Conigrave et al., 2003). Even though the regular drinkers may have no overtphysical effects from excessive alcohol use, their hepatic enzymes are often elevated. Theelevations of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) mayindicate hepatocellular damage from heavy drinking, while the elevation of gamma-glutamyltransferase (GGT), a biliary canalicular enzyme, is partly the result of enzyme induction andpartly due to damage of the hepatic system (Whitfield, 2001; Conigrave et al., 2003). Theelevated serumGGT level may occur in about 85–90% of patients ingestingmore than 50 g ofalcohol daily and may be a useful pointer to the ongoing alcohol abuse (Sharpe, 2001).Further, the amount of alcohol consumption, irrespective of the form in which it is taken, isthe most important risk factor for development of ALD.

The studies exploring the relation between self-reported alcohol consumption and GGTlevels in Indian population are very scant (Desai et al., 1996; Das & Vasudevan, 2005). Thelevels of alcohol intake at which the biochemical liver parameters become abnormal have notbeen established in Indian setting. Given the ethnic differences in the pharmacokinetics ofalcohol metabolism, it is important to explore the relationship between the quantity of alcoholconsumption and the elevation of liver enzymes in Indian patients.

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This study aims to assess the level of agreement between urinalysis and self-report for licitand illicit drug use in alcohol-dependent patients and to examine the relationship of bio-chemical measures with self-reported alcohol consumption.

Methods

The study was conducted at a tertiary care hospital for substance use treatment in India. Thehospital is also actively engaged in teaching, training and research activities. The centre has nodefined catchment area and patients from several states of India seek treatment for addictivedisorders. The study was conducted prospectively over a period of 6 months.

Study population

Consecutive patients presenting with a regular current use of alcohol, fulfilling Diagnosticand Statistical Manual, 4th edition Text Revision (DSM-IV TR) (American PsychiatricAssociation, 2000) diagnostic criteria for alcohol dependence syndrome and willing toprovide biological sample for assessment were included. The diagnosis and clinical assess-ment were conducted by a psychiatrist. Following inclusion, the socio-demographic profile,alcohol use characteristics and medical co-morbidity, if any, were recorded. From eachpatient, the recent (previous 72 h) use of licit and illicit drugs in any form was enquiredusing a structured questionnaire. The patient was the only informant and family memberswere not interviewed.

Thereafter, from each patient, 5 ml of blood sample and 10 ml of urine sample werecollected under close supervision by the centre’s laboratory staff. All the samples wereanalysed at the drug abuse testing laboratory of the centre. The blood sample was centrifugedshortly after collection and plasma and urine were stored at –20�C till analysis. The laboratorypersonnel conducting the urinalysis and blood tests were blinded to the self-reported sub-stance use status of the patients. The study was conducted in accordance with ethicalstandards mentioned in the declaration of Helsinki and written informed consent wasobtained from all patients.

Biochemical liver function tests and urine analysis

All the biochemistry reagents were purchased from Roche Diagnostics (Mannheim, Germany)and the analysis was performed on echo plus biochemistry autoanalyser (Logotech Pvt. Ltd.,NewDelhi, India). The biochemical parameters assessed in the blood sample include bilirubin,total protein, albumin, globulin, serum transaminases (AST and ALT) and GGT. Urinalysisfor illicit substances and commonly abused prescription drugs was done by cassette test (AlfaScientific Designs Inc., Poway, CA, USA), based on the principle of competitive bindingimmunoassay. Assay was carried out as directed by the manufacturers. The cut-off values foreach drug were opioids, benzodiazepines and cocaine 300 ng/ml, barbiturates and cotinine 200ng/ml and cannabis 50 ng/ml. Urine drug level above the given cut-off values was considered tobe positive for the particular drug.

Statistical methods

Descriptive statistics were used to describe the socio-demographic, clinical and laboratorycharacteristics. Cohen’s kappa (Cohen, 1960) was calculated as a measure for the degree of

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agreement between self-report and urine test result beyond that is expected by chance. Theinterpretation of kappa coefficient was done as per Landis and Koch (1977) as follows: values< 0 indicate no agreement, 0–0.20 slight, 0.21–0.40 fair, 0.41–0.60 moderate, 0.61–0.80substantial and 0.81–1.0 almost perfect agreement. In view of non-normal/skewed distribu-tion of data, Kruskal–Wallis test was used as a nonparametric test for group mean differencesfor biochemical parameters. The post hoc pairwise comparisons of significant variables wereconducted using Mann–Whitney tests. A p-value of 0.05 was taken to indicate statisticalsignificance.

Results

Sample characteristics

A total of 119 male consecutive alcohol-dependent patients who presented over the 6-monthstudy duration were included as per defined criteria. Themean age of the sample was 36.44�9.02 years. The mean duration of dependent use was 16.01 � 8.85 years. Table I shows thesocio-demographic characteristics.

Concordance between urinalysis and self-report for substance use

The self-report for co-occurring substance use in alcohol-dependent patients was comparedwith the urinalysis results. The concordance between self-report and objective measures isshown in Table II. Considering urinalysis as a gold standard, the use of opiates, cannabis,

Table I. Socio-demographic and clinical characteristics of alcohol-dependent patients(N ¼ 119)

Sample descriptivesVariable Mean�SD/frequency

Age (years) 36.44 � 9.02Education (years)Illiterate 15 (12.6%)Primary 34 (28.6%)High school 22 (18.5%)Higher secondary 15 (12.6%)Graduate 25 (21.0%)Postgraduate 8 (6.7%)

Marital statusMarried 99 (83.2%)Unmarried 20 (16.8%)

Occupational typeUnskilled worker 32 (33.6%)Semi-skilled worker 19 (15.9%)Farmer 15 (12.6%)Government job 17 (14.3%)Self-employed 26 (21.8%)Skilled/professional 10 (16.8%)

Occupational statusCurrently working 87 (73.1%)Currently not working 32 (26.9%)

Note: SD, standard deviation.

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nicotine and benzodiazepines was found to be present in 2.5%, 4.2%, 5.9% and 28.8% ofpatients, respectively, even though patients reported no use of these drugs. The false-positiverates for self-report varied between 0.8% and 6.8% for various substances as shown in Table II.

Biochemical markers and their relation to self-reported alcohol consumption

The biochemical liver parameters for the sample have been described in Table III. Thesample was subdivided into three patient groups based on average daily alcohol consumption.The difference in the mean ranks of liver function tests in the patient groups was assessed bythe nonparametric Kruskal–Wallis test as shown in Table IV. The post hoc tests wereperformed for significant differences using Mann–Whitney tests for pairwise comparisonbetween two groups (Table IV).

Discussion

This study compared the urinalysis and biochemical liver markers with the self-reported druguse and alcohol consumption, respectively, in a sample of alcohol-dependent patients. All the

Table II. Concordance between self-report and urinalysis for co-occurring substance use in alcohol-dependentpatients (N ¼ 119)

Self-report

Urinalysis

Cohen’s kappa (κ)Positive Negative

Nicotine Positive 106 (89.1%) 3 (2.5%) 0.333Negative 7 (5.9%) 3 (2.5%)

Opiates Positive 1 (0.8%) 8 (6.8%) 0.133Negative 3 (2.5%) 106 (89.9%)

Cocaine Positive 0 (0%) 1 (0.8%) NANegative 0 (0%) 118 (99.2%)

Cannabis Positive 11 (9.3%) 4 (3.4%) 0.666Negative 5 (4.2%) 98 (83.1%)

Benzodiazepines Positive 11 (9.3%) 2 (1.7%) 0.251Negative 34 (28.8%) 71 (60.2%)

Note: Concordance κ ¼ 0�0.20 (slight); 0.21�0.40 (fair); 0.41�0.60 (moderate).

Table III. Biochemical tests for liver functions in consecutive alcohol-dependent patients (N ¼ 119)

Variable Bilirubin (mg/dl) Albumin (g/dl) AST (units/l) ALT (units/l) GGT (units/l)

Median 0.62 4.51 51.90 48.20 77.00RangeMinimum 0.13 2.43 12.00 11.50 12.80Maximum 8.10 5.58 425.70 337.00 2583.00

Abnormal range (%) 23.5% (") 5.5% (#) 52.1% (") 48.7% (") 67.2% (")Enzyme elevationLess than 1 time 26.8% 33.6% 22.7%>1 to �3 times 18.9% 7.9% 20.1%More than three times 6.4% 7.2% 24.4%

Note: AST, aspartate transferase; ALT, alanine transferase; GGT, gamma-glutamyl transferase.

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patients were male, which is in accordance with previous studies on substance users fromIndia (Jain, 2004; Das & Vasudevan, 2005; Pattanayak et al., 2010). The socioculturalbarriers often prevent women substance users from seeking treatment freely in conservativesocieties.

The level of concordance between self-report and urinalysis ranged from slight tomoderatefor various drugs of abuse in alcohol-dependent patients. In those with a negative self-report,urinalysis could detect opiates in 2.5%, cannabis in 4.2%, nicotine in 5.9% and benzodiaze-pines in 28.8% of the sample. The denial for illicit drugs and nicotine appears to be present ina small but significant percentage of patients. Nonprescription benzodiazepine use wasreported by only 11% of patients; however, it was found to be positive in 38% of the sampleas per urinalysis results. This suggests that a large majority of the alcohol-dependent patientsdenied benzodiazepine use on direct questioning. In a previous Indian study, benzodiazepineuse was denied by 25% of the alcohol users in their self-report, which, however, was found tobe positive on urinalysis (Pattanayak et al., 2010). In a separate study, it was observed thatbenzodiazepines were the most frequent under-reported drugs among the inconsistent self-reports provided by substance-using patients (Neale & Robertson, 2003). The results, how-ever, contrast the findings from some other studies showing a satisfactory agreement betweenself-reported benzodiazepine use and objective measures in alcohol users (Fishbain et al.,1999; Jain et al., 2006).

The inaccurate self-report for co-occurring drug use, for example, benzodiazepines, mayhave important clinical and treatment implications. If concurrent drug use, for example,

Table IV. Relation of biochemical liver functions to alcohol consumption (N ¼ 119)

Variables

Average daily self-reported alcohol consumption(past 30 days)

Kruskal–Wallis testby mean ranks

Post hoc(Mann–Whitney)

Group A �0.5bottle (n ¼ 45)

Group B >0.5 and<1.5 bottles (n ¼ 53)

Group C �1.5bottles (n ¼ 21) χ (p) p

Bilirubin 0.87 � 1.86 0.73 � 0.46 0.72 � 0.36 0.089 (0.956) –

Albumin 4.43 � 0.56 4.47 � 0.58 4.38 � 0.59 0.757 (0.685) –

AST 68.16 � 69.90 78.60 � 78.32 113.19 � 82.09 8.36 (0.015�) A versus B: 0.603B versusC: 0.019�

% elevated 42.2% 50.9% 76.2% A versusC: 0.004�

ALT 61.81 � 64.45 65.45 � 69.93 89.42 � 71.87 6.23 (0.044�) A versus B: 0.839B versusC: 0.030�

% elevated 42.2% 47.2% 66.7% A versusC: 0.016�

GGT 123.88 � 134.26 202.31 � 402.07 284.24 � 288.23 8.99 (0.011�) A versus B: 0.692B versusC: 0.007�

% elevated 60.0% 62.3% 95.2% A versusC: 0.006�

Notes: AST, aspartate transferase; ALT, alanine transferase; GGT, gamma-glutamyl transferase. 1 bottle is equivalentof 750ml local liquor with, 20% (alcohol by volume), amounting to 15 units of alcohol; statistical analysis byKruskal–Wallis nonparametric test for analysis of variance by mean ranks; pairwise comparisons by Mann–Whitney test.�p < 0.05.

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benzodiazepines, has not been reported to the treating clinician, the patient is unlikely toreceive an adequate replacement treatment and may develop distressing or even complicatedwithdrawal symptoms (Wesson et al., 2005). It is also likely that benzodiazepine use mayescalate during the abstinence from alcohol and such patients may require a more intensivefollow-up care. While this study did not focus on the underlying reasons for benzodiazepineuse, patients may use them for augmentation of alcohol effects, for insomnia or as a self-medication to counter the withdrawals from alcohol. The urine cassette used in this study is aquick and effective method to detect benzodiazepine and other drug use. With quick avail-ability of results and the potential to avoid clinical consequences associated with undetecteddrug use, it can act as a useful adjunct to clinicians and a boon for patients. The self-report fora small percentage of sample (0.8–6.8%) was found to be false positive, that is, a negativeurinalysis in spite of a positive self-report for recent substance use. This could be due tomultiple reasons, viz. the patient is over-reporting the drug use or has used very low quantitiesof a substance or has taken the drug immediately prior to his visit to the treating physician orhas used it beyond the detection time limit of urine cassette test.

In this study, GGT was raised in 67.2% of the study sample comprising alcohol-dependentusers. This finding is in accordance with previous literature, which suggests that the serumlevels of GGT are elevated in regular alcoholics and nearly 75% of alcohol-dependent indivi-duals have abnormally raised levels (Sharpe, 2001; Das et al., 2003). Further, the serum levelsof GGT appear to vary considerably in response to different amounts of alcohol consumption.In this study, the serum GGT levels were elevated in 95.2% of those with higher self-reportedconsumption compared to 60–62% of those with a low to moderate alcohol use. GGT appearsto corroborate with the self-reported alcohol use, particularly for heavy drinkers.

AST and ALT were elevated in 76.2% and 66.7% of the patients with self-reported heavyalcohol use. AST and ALT were able to distinguish the group with heavy consumption fromthose with low and moderate alcohol. The liver enzymes are not raised in all patients withalcohol use. The level of serum transaminases depends markedly on the degree of liverdamage, which is more frequent with heavy usage. There is often a greater elevation ofAST compared with ALT in cases of alcohol-induced hepatic derangements (Sharpe,2001; Litten et al., 2010). The biochemical liver markers used in the study appear to beespecially useful for detection of heavy drinking. These can be a useful adjunct in clinicalsituations, especially in patients who are unwilling to provide accurate information regardingtheir drinking. The concurrent use of liver biomarkers can augment the accuracy of self-report measures to a certain extent (Conigrave et al., 2002; Litten et al., 2010).

The study has certain limitations. The study focused only on dependent users and findingsmay differ in alcohol abusers or occasional drinkers. The findings cannot be generalized toother kind of study settings as this study focused on treatment-seeking alcohol users. The useof multiple tests may have contributed to a potential increase in type 1 errors in statisticaltesting. Several other alcohol use parameters, for example, pattern of drinking, may influencethe biochemical markers and were not studied. The study was planned in a routine clinicalsetting and therefore more recent markers of alcohol used for research purposes were notemployed. The liver markers for alcoholism have limitations in terms of sensitivity andspecificity and could be raised in other liver disorders as well. Similarly, urinalysis haslimitations in terms of what it can reveal about the validity of self-report. It can detect onlythe recent use of a substance, generally 48–72 hours earlier, and is unable to detect very lowquantities of a drug below the sensitivity threshold. In spite of these limitations, this studyurges for a routine use of quick and objective methods to corroborate the self-report in

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treatment seekers. The service provision at a treatment centre should also be geared toeffectively deal with and minimize the inaccurate self-reporting by patients.

To conclude, the use of concurrent drugs, for example, benzodiazepines, may be denied byalcohol-dependent patients, even on specific probing. It is therefore necessary to have quickand effective laboratory tests to corroborate patient’s self-report and easily detect the con-current drug use by objective means. The urine cassette test is a useful adjunct for a clinicianand can serve to reveal the misreporting by patient and may be even discouraging it in futurevisits. The traditional alcoholic biomarkers appear to be useful in verifying the self-reportedconsumption of alcohol and can distinguish heavy drinkers from low and moderate drinkers.Use of alternate corroborative measures, for example, family member’s report, must beemployed in the clinical setting. Future research and policy interventions should be gearedtowards addressing and minimizing the inaccurate self-report.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the contentand writing of this article.

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