EMF and subjective symptoms...Schreier SPM, 2006 4th EBEA Course. M. Röösli, subjective symptoms,...

Ebea, Erice (Sicily), 29/03/2008

EMF and subjective symptoms

M. Röösli, PhDUniversity of BernInstitute of Social and Preventive Medicine

4th EBEA Course. M. Röösli, subjective symptoms, 29/03/2008

2

Content

> Electromagnetic hypersentitivity (EHS):Definitions/prevalence

> Perception of low level RF-EMF> Symptoms and RF-EMF: short term> Therapeutic options> Conclusions


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Definitions

> Terms:— Electromagnetic Hypersensitivity (EHS)— Electrosensitivity— Idiopathic environmental Intolerances (IEI-EMF)

> EHS is characterized by a variety of non-specificsymptoms, which afflicted individuals attribute toexposure to EMF (WHO, fact sheet N° 296).

> No established biological mechanism


4

Symptoms attributed to EMF

Proportion [%]

Data from a representative survey in Switzerland(n=2048, thereof 5% attributed symptoms to EMF)

Schreier SPM, 2006


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Attributed causes

Proportion [%]

Schreier SPM, 2006

80% of the EHS suspected specific EMF sources.


6

Subjective

perception of

EMF exposure

II

other factors

Subjective

perception of

health state

III

Perception of

EMF as a health

risk

Attributing health

symptoms to EMF

(EHS)subjective

pathway Subjective

perception of

EMF exposure

II

other factors

Subjective

perception of

health state

III

Perception of

EMF as a health

risk

Attributing health

symptoms to EMF

(EHS)subjective

pathway

?

Objective

distribution of

EMF in the

environment

I

Objective

health state

IV

other factors

biological

mechanism

?

Objective

distribution of

EMF in the

environment

I

Objective

health state

IV

other factors

biological

mechanism

Schreier SPM, 2006

EHS model


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Prevalence

> Prevalence:— Stockholm: 1.5% (Hillert, SJWEH, 2002)— California: 3.2% (Levallois, EHP, 2002)— United Kingdom: 4% (Eltiti, 2007)— Germany: 8-10% (Infas 2002-2006)— Switzerland: 5.0% (Schreier, SPM, 2006)— Austria: women: 4.2%, men:1.7% (Leitgeb & Schröttner,

BioEM, 2003)

> A substantial part of EHS individuals claims toimmediately perceive low level EMF when theyare exposed (56%) and to develop symptomswithin a few minutes (53%) (Röösli, 2004).


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3 different aspects of EHS

> Perception of low-level fields: sensibility (Leitgeband Schröttner, 2003)provocation studies

> Symptoms and RF-EMF: short termrandomized trials/human laboratory study

> Symptoms and RF-EMF: long termepidemiological/observational studies


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Provocation study

> Repeated tests with different exposureconditions (incl. Sham): randomised

> Neither the study participants nor the studyassistant know the exposure condition: doubleblind.

> Study participants state whether they perceiveexposure or not (or symptoms).


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Laboratory of the Swiss UMTS study


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Perceived field intensity

> Subjective assessment of the perceived field on a 100 visualanalog scale (VAS):

nein, gar nicht ja, sehr stark

Wert 0 Wert 36 Wert 100


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Perceived field intensity(Regel et al, EHP, 2006)

0 V/m1 V/m10 V/m


13

Perception of singulartranscranial magnetic stimuli(Frick,et al, BioEM, 2005)

EHS individuals:Controls:

EHS individuals showed more false alarms.Differentiation between sham and real exposure waspoor in EHS individuals


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Provocation studies

> Systematic literature search: 7 double-blind,peer-reviewed papers on RF-EMF (until August,2007)

> Exposure:— Mobile phone: 5 GSM 900— base station: 1 GSM, 2 UMTS

> Exposure duration: 2-50 minutes> Number of sessions per individual: 3-12> Collectives: 182 hypersensitive (EHS)

individuals and 332 healthy volunteers.


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Meta-analysis of provocation studies(correct field detection rate)

Overall

Studies with non-EHS collective

Rubin, 2006

Studies with EHS collective

Study

Radon, 1998

Oftedal, 2007

Eltiti, 2007 (5')

Loughran, 2005

Eltiti, 2007 (5')

Subtotal

Regel, 2006

Eltiti, 2007 (50')

Subtotal

Eltiti, 2007 (50')

Regel, 2006

Rubin, 2006

Wolf, 2006

0.04 (-0.02, 0.11)

0.04 (-0.15, 0.25)

ES (95% CI)

0.20 (-0.04, 0.45)

0.07 (-0.14, 0.28)

0.02 (-0.12, 0.18)

0.23 (-0.09, 0.51)

-0.01 (-0.20, 0.21)

0.07 (-0.02, 0.17)

-0.10 (-0.39, 0.20)

0.02 (-0.13, 0.18)

0.02 (-0.07, 0.10)

0.08 (-0.14, 0.35)

0.13 (-0.25, 0.49)

-0.03 (-0.22, 0.18)

0.09 (-0.26, 0.59)

0.04 (-0.02, 0.11)

0.04 (-0.15, 0.25)

ES (95% CI)

0.20 (-0.04, 0.45)

0.07 (-0.14, 0.28)

0.02 (-0.12, 0.18)

0.23 (-0.09, 0.51)

-0.01 (-0.20, 0.21)

0.07 (-0.02, 0.17)

-0.10 (-0.39, 0.20)

0.02 (-0.13, 0.18)

0.02 (-0.07, 0.10)

0.08 (-0.14, 0.35)

0.13 (-0.25, 0.49)

-0.03 (-0.22, 0.18)

0.09 (-0.26, 0.59)

worse than chance better than chance 0-.6 -.4 -.2 0 .2 .4 .6

Röösli, Env Res, 2008


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Mobile phone vs. base stationstudies

Overall

Loughran, 2005

Eltiti, 2007 (50')

Regel, 2006

Subtotal

Subtotal

Oftedal, 2007

Wolf, 2006

Base station exposure:

Regel, 2006

Radon, 1998

Eltiti, 2007 (50')

Rubin, 2006

Eltiti, 2007 (5')

Eltiti, 2007 (5')

Rubin, 2006

Mobile telephone exposure:

Study

0.04 (-0.02, 0.11)

0.23 (-0.09, 0.51)

0.08 (-0.14, 0.35)

-0.10 (-0.39, 0.20)

0.02 (-0.06, 0.10)

0.09 (-0.02, 0.20)

0.07 (-0.14, 0.28)

0.09 (-0.26, 0.59)

0.13 (-0.25, 0.49)

0.20 (-0.04, 0.45)

0.02 (-0.13, 0.18)

0.04 (-0.15, 0.25)

-0.01 (-0.20, 0.21)

0.02 (-0.12, 0.18)

-0.03 (-0.22, 0.18)

ES (95% CI)

0.04 (-0.02, 0.11)

0.23 (-0.09, 0.51)

0.08 (-0.14, 0.35)

-0.10 (-0.39, 0.20)

0.02 (-0.06, 0.10)

0.09 (-0.02, 0.20)

0.07 (-0.14, 0.28)

0.09 (-0.26, 0.59)

0.13 (-0.25, 0.49)

0.20 (-0.04, 0.45)

0.02 (-0.13, 0.18)

0.04 (-0.15, 0.25)

-0.01 (-0.20, 0.21)

0.02 (-0.12, 0.18)

-0.03 (-0.22, 0.18)

ES (95% CI)



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Overall

5

30

30

45

50

5

30

2

50

5

50

Duration

45

0.04 (-0.02, 0.11)

-0.01 (-0.20, 0.21)

-0.03 (-0.22, 0.18)

0.07 (-0.14, 0.28)

0.13 (-0.25, 0.49)

0.02 (-0.13, 0.18)

0.02 (-0.12, 0.18)

0.04 (-0.15, 0.25)

0.20 (-0.04, 0.45)

0.08 (-0.14, 0.35)

0.09 (-0.26, 0.59)

0.23 (-0.09, 0.51)

ES (95% CI)

-0.10 (-0.39, 0.20)

0.04 (-0.02, 0.11)

-0.01 (-0.20, 0.21)

-0.03 (-0.22, 0.18)

0.07 (-0.14, 0.28)

0.13 (-0.25, 0.49)

0.02 (-0.13, 0.18)

0.02 (-0.12, 0.18)

0.04 (-0.15, 0.25)

0.20 (-0.04, 0.45)

0.08 (-0.14, 0.35)

0.09 (-0.26, 0.59)

0.23 (-0.09, 0.51)

ES (95% CI)

-0.10 (-0.39, 0.20)


Sorted by exposure duration

[min]


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Meta regression

-0.193 to 0.2130.010Exposure duration [h]

-0.068 to 0.2020.067Mobile phone exposure

-0.078 to 0.1780.050EHS collective

95% Conf. intervalCoefficient

Röösli, Env Res, 2008


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Short term effects: Symptomscore after exposure(Regel et al, EHP, 2006)

0 V/m1 V/m10 V/m


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Example: Scandinavian Headachstudy (Oftedal et al, 2007)

> Open provocation with 38 persons, who reportheadache when using a mobile phone.

> 24 persons reacted with headache during theopen provocation.

> 17 persons agreed to participate at a doubleblind experiment.

> Under double blind condition: no associationbetween reported headache and exposure.

> Evidence for nocebo effect.


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Nocebo

> contrary to placebo> development of symptoms due to expectation

(e.g. concern)


22

12

34

5

0 50 100 0 50 100

Sensitive Group Non-sensitive Group

current disposition linear fit

Sco

re

Perceived Field (VAS scale)

Symptom score after exposurevs. perceived field intensity(Regel et al, EHP, 2006)


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Short term effects

> Systematic literature search: 10 peer-reviewed trials onRF-EMF and symptoms (main outcome) (until Dec.2008)

> Design: 9 cross-over, 1 mixed> Blinding: 7 double, 2 single, 1 “blind”> Exposure:

— Mobile phone: 1 NMT, 6 GSM900, 1 GSM1800— base station: 1 GSM, 2 UMTS

> Exposure duration: 30-60 minutes (8), 3h (1), and 6nights (1)

> Collectives: 232 EHS and 460 non-EHS individuals


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Short term effects: randomised doubleblind trials

Rubin2006

Regel2006 Nocebo effects observed

No nocebo effect investigated

Oftedal2007

Wilen2006

Eltiti2007

Fritzer2007

Koivisto2001

Hietanen2001

No effect

Effect

Ridder-vold 2008

Hillert2008


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Summary I: we know…

> EHS is a self declaration based on own experiences.> The vast majority who claims to be able to perceive low

level EMF is not able to perceive fields in a laboratorydouble blind setting.

> EHS individuals overestimate their own exposure (morefalse alarms).

> Nocebo effects occur.> Short term effects from everyday EMF exposures on

well-being are unlikely.> There is no evidence that EHS individuals are more

susceptible to EMF than non EHS-individuals.


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Summary II: We do not know…

> Is there a small minority of individuals who is able toperceive low level EMF?

> Does whole body exposure close to the reference valuecause symptoms (> 10 V/m)?

> Are there any long term exposure effects (>1h)?> Does the signal characteristic matter?> Is there a difference between EHS and reference

individuals (e.g. blood pressure, cortical excitability,etc.)?

> What are the most effective and accepted therapeuticoptions for EHS individuals?


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Do EHS individuals differ fromthe rest of the population?

— Differences observed for:– Self reported symptoms (Regel 2006, Frick 2005, etc.)– Heart rate variability (Lyskov 2001, Wilen 2006)– Cortical excitability (Landgrebe 2007)– Hyperresponsiveness to sensor stimulation, heightened arousal

(Lyskov 2001)– Electrodermal activity (Lyskov 2001), skin conductance (Eltiti,

2007)

— No differences for cholinesterase activity (Hillert2001)

— Inconsistent results for heart rate (Lyskov 2001, Eltiti2007)

> Real differences or a psycho-physiologicalstress response when participating in EMFstudies?


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Therapeutic options

> Placebo works against the nocebo phenomena(e.g. "to neutralise" the exposure).

> Shiatsu worked in one trial (placebo?).> Affected individuals reported that reduction of

exposure was helpful, however, no beneficialeffect occurred in placebo-controlled studies(placebo).

> Some success was reported from cognitivebehavioural therapy, however, often notaccepted.


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Cognitive behavioural therapy

Rubin et al., 2006


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Sensitivity to environmental factors

> Different sensitivities to environmental factors iswell established:— e.g. not everybody reacts in the same way to heat,

coldness, etc.— e.g. not every smoker develops lung cancer

> Thus, if there were health effects from EMF:— not everybody would react -> different sensitivities— Currently, there is no evidence that such sensitivities

can be self perceived as EHS do claim.

> Are there long term EMF effects?

EMF and subjective symptoms...Schreier SPM, 2006 4th EBEA Course. M. Röösli, subjective symptoms,...

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