Suicide and depression abstracts

Epidemiological studies of suicide and depression and magnetic fields

We provide here the abstracts for the major epidemiological studies of magnetic fields or power lines and suicide and depression. See also a summary of the evidence.

Baris and Armstrong 1990Suicide, occupational
Baris, Armstrong, Deadman and Theriault 1996Suicide, occupational
Beale, Pearce, Conroy, Henning and Murrell 1997Psychological effects, power lines
Dowson, Lewith, Campbell, Mullee and Brewster 1988Headaches and depression, power lines
McDowall 1986Mortality (including suicide), power lines
McMahan, Ericson and Meyer 1994Depression, power lines
Perry, Pearl and Binns 1989Depression, residential magnetic field
Perry, Reichmanis, Marino and Becker 1981Suicide, residential magnetic field
Poole, Kavet, Funch, Donelan, Charry and Dreyer 1993Headaches and depression power lines
Reichmanis, Perry, Marino and Becker 1979Suicide, power lines
Savitz, Boyle and Holmgreen 1994Depression, occupation
van Wijngaarden, Savitz, Kleckner, Cai and Loomis 2000Suicide, occupation
van Wijngaarden, Savitz, Kleckner, Cai and Loomis 2000Suicide, occupation
Verkasalo, Kaprio, Varjonen, Romanov, Heikkila and Koskenvuo 1997Depression, power lines
Zyss, Dobrowolski and Krawczyk 1997Depression, power lines
Zyss 1999Depression, power lines

 

 

Br J Ind Med 1990 Nov;47(11):788-9
Suicide among electric utility workers in England and Wales.

Baris D, Armstrong B.

[letter – no abstract]

Occup Environ Med 1996 Jan;53(1):17-24
A case cohort study of suicide in relation to exposure to electric and magnetic fields among electrical utility workers.

Baris D, Armstrong BG, Deadman J, Theriault G.

Department of Occupational Health, Faculty of Medicine, McGill University, Montreal, Canada.

OBJECTIVES--This case cohort study examines whether there is an association between exposure to electric and magnetic fields and suicide in a population of 21,744 male electrical utility workers from the Canadian Province of Quebec. METHODS--49 deaths from suicide were identified between 1970 and 1988 and a subcohort was selected comprising a 1% random sample from this cohort as a basis for risk estimation. Cumulative and current exposures to electric fields, magnetic fields, and pulsed electromagnetic fields (as recorded by the POSITRON meter) were estimated for the subcohort and cases through a job exposure matrix. Two versions of each of these six indices were calculated, one based on the arithmetic mean (AM), and one on the geometric mean (GM) of field strengths. RESULTS--For cumulative exposure, rate ratios (RR) for all three fields showed mostly small non-significant increases in the medium and high exposure groups. The most increased risk was found in the medium exposure group for the GM of the electric field (RR = 2.76, 95% CI 1.15-6.62). The results did not differ after adjustment for socioeconomic state, alcohol use, marital state, and mental disorders. There was a little evidence for an association of risk with exposure immediately before the suicide. CONCLUSION--Some evidence for an association between suicide and cumulative exposure to the GM of the electric fields was found. This specific index was not initially identified as the most relevant index, but rather emerged afterwards as showing the most positive association with suicide among the 10 indices studied. Thus the evidence from this study for a causal association between exposure to electric fields and suicide is weak. Small sample size (deaths from suicide) and inability to control for all potential confounding factors were the main limitations of this study.

Bioelectromagnetics 1997;18(8):584-94
Psychological effects of chronic exposure to 50 Hz magnetic fields in humans living near extra-high-voltage transmission lines.

Beale IL, Pearce NE, Conroy DM, Henning MA, Murrell KA.

Department of Psychology, University of Auckland, New Zealand.

The validity of several published investigations of the possibility that residential exposures to 50 Hz or 60 Hz electromagnetic fields might cause adverse psychological effects, such as suicide and depression, may have been limited by inadequate controlling for confounders or inadequate measurement of exposures. We investigated the relationships between magnetic field exposure and psychological and mental health variables while controlling for potential confounders and careful characterising individual magnetic field exposures. Five-hundred-and-forty adults living near transmission lines completed neuropsychological tests in major domains of memory and attentional functioning, mental health rating scales and other questionnaires. Magnetic field measurements were taken in each room occupied for at least one hour per day to provide an estimate of total-time-integrated exposure. The data were subjected to joint multivariate multiple regression analysis to test for a linear relation between field exposure and dependent variables, while controlling for effects of possible confounders. Performance on most memory and attention measures was unrelated to exposure, but significant linear dose-response relationships were found between exposure and some psychological and mental health variables. In particular, higher time-integrated exposure was associated with poorer coding-test performance and more adverse psychiatric symptomatology. These associations were found to be independent of participants' beliefs about effects of electromagnetic fields.

Practitioner 1988 Apr 22;232(1447):435-6 
Overhead high-voltage cables and recurrent headache and depressions.

Dowson DI, Lewith GT, Campbell M, Mullee MA, Brewster LA.

[No abstract in PubMed]
Br J Cancer 1986 Feb;53(2):271-9
Mortality of persons resident in the vicinity of electricity transmission facilities.

McDowall ME.

Several studies have raised the possibility that exposure to electrical and/or magnetic fields may be injurious to health in particular by the promotion or initiation of cancer. To investigate whether the electricity transmission system presents a long term hazard to public health, the mortality of nearly 8,000 persons, identified as living in the vicinity of electrical transmission facilities at the time of the 1971 Population Census, has been followed to the end of 1983. All identified transmission installations within pre-defined areas were included in the study with the result that the greater part of the study group were believed to be resident near relatively low voltage sub-stations. Overall mortality was lower than expected and no evidence of major health hazards emerged. The only statistically significant excess mortality was for lung cancer (in women overall, and in persons living closest to the installations); this result is difficult to interpret in the absence of smoking data, and is not supported by other evidence but does not appear to be due to the social class distribution of the study group. The study did not support previously reported associations of exposure to electro-magnetic fields with acute myeloid leukaemia, other lymphatic cancers and suicide.

Am J Epidemiol 1994 Jan 1;139(1):58-63
Depressive symptomatology in women and residential proximity to high-voltage transmission lines.

McMahan S, Ericson J, Meyer J.

Department of Environmental Health, School of Social Ecology, University of California, Irvine 92717.

A number of epidemiologic studies indicate an association between depression and proximity to high-voltage transmission lines. These studies have been criticized, however, for using surrogate measures of electromagnetic fields and unstandardized measures of depression. In an effort to overcome these limitations, the authors administered the Center for Epidemiological Studies Depression scale (CES-D) in 1992 to 152 women in Orange County, California, who lived either adjacent to a transmission line or one block away. The results indicated that the average magnetic field level is 4.86 mG at the front door of homes adjacent to transmission lines and 0.68 mG at the front door of homes one block away. There was no significant difference in CES-D scores between the groups when demographic variables were controlled for. The homogeneity of the study population may limit the generalizability of findings.

Public Health 1989 May;103(3):177-80
Power frequency magnetic field; depressive illness and myocardial infarction.

Perry S, Pearl L, Binns R.

Surveys were made to determine whether susceptibility to depressive illness and to myocardial infarction of people living in Wolverhampton was related to the intensity of 50 Hz magnetic field outside their homes. Comparing case with control addresses it was found that the field strength was significantly higher for depressive illness (P = 0.033) but not for myocardial infarction.

Health Phys 1981 Aug;41(2):267-77
Environmental power-frequency magnetic fields and suicide.

Perry FS, Reichmanis M, Marino AA, Becker RO.

[no abstract in PubMed]

Am J Epidemiol 1993 Feb 1;137(3):318-30
Depressive symptoms and headaches in relation to proximity of residence to an alternating-current transmission line right-of-way.

Poole C, Kavet R, Funch DP, Donelan K, Charry JM, Dreyer NA.

Epidemiology Resources Inc., Newton Lower Falls, MA 02162.

Electric power transmission lines have become objects of public controversy. Hypotheses have linked neurobehavioral effects to the electric and magnetic fields that these lines produce. The authors conducted a telephone interview survey in November 1987 to assess the prevalence of depressive symptoms and headache in relation to proximity of residence to an alternating-current transmission line in the United States. Proximity to the line, defined as residing on a property abutting the right-of-way or being able to see the towers from one's house or yard, was positively associated with a measure of depressive symptoms. The association was not explained by demographic variables associated with depression or by attitudes about power lines or other environmental issues. The estimated prevalence odds ratio was 2.8 (95% confidence interval (CI) 1.6-5.1). The estimate did not change appreciably when the definitions of depressive symptoms or of proximity to the line were altered. Nonmigraine headaches had a weaker association with proximity to the line (odds ratio = 1.5, 95% CI 0.76-2.8), and self-reported migraine headaches exhibited no association (odds ratio = 0.99, 95% CI 0.29-3.4). Additional studies of psychological and behavioral measures should be conducted in relation to electric and magnetic fields, with a strong emphasis on improved exposure assessment.

Physiol Chem Phys 1979;11(5):395-403
Relation between suicide and the electromagnetic field of overhead power lines.

Reichmanis M, Perry FS, Marino AA, Becker RO.

Laboratory studies have shown that electromagnetic fields similar to those from high-voltage transmission lines can produce biological effects. Surveys of the actual effects of such lines on exposed individuals usually have been hampered by complicating factors tending to blur the data. By means of a new approach, however, correlation has been established between the presence of transmission-line fields and the occurrence of suicides in part of the Midlands of England.

Am J Ind Med 1994 Feb;25(2):165-76
Prevalence of depression among electrical workers.

Savitz DA, Boyle CA, Holmgreen P.

Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill 27599-7400.

To address the possible association between electric and magnetic field exposure and depression, we analyzed data from the Vietnam Experience Study. In order to compare the risk of diagnosed depression, depressive symptoms, and elevations in personality scales indicative of depression, we classified employed participants as electrical workers (N = 183) and nonelectrical workers (N = 3,861) and compared their scores on the Diagnostic Interview Survey (DIS) and the Minnesota Multiphasic Personality Inventory (MMPI). Electrical workers in the aggregate showed little evidence of increased risk, with the possible exception of an increase in elevated MMPI depression scores among short-term workers. Data on electricians yielded indications of increased risk for several markers of depression. Despite the limited number of electrical workers, uncertainty regarding exposure, and our inability to address other workplace exposures, these results suggest that electrical workers in general are not at increased risk for depression. However, our results encourage further evaluation of depression among electricians.

Occup Environ Med 2000 Apr;57(4):258-63
Exposure to electromagnetic fields and suicide among electric utility workers: a nested case-control study.

van Wijngaarden E, Savitz DA, Kleckner RC, Cai J, Loomis D.

Department of Epidemiology, School of Public Health, The University of North Carolina, Chapel Hill, NC, USA.

OBJECTIVES: This nested case-control study examines mortality from suicide in relation to estimated exposure to extremely low frequency electromagnetic fields (EMFs) in a cohort of 138,905 male electric utility workers. METHODS: Case-control sampling included 536 deaths from suicide and 5348 eligible controls. Exposure was classified based on work in the most common jobs with increased exposure to magnetic fields and indices of cumulative exposure to magnetic fields based on a measurement survey. RESULTS: Suicide mortality was increased relative to work in exposed jobs and with indices of exposure to magnetic fields. Increased odds ratios (ORs) were found for years of employment as an electrician (OR 2.18; 95% confidence interval (95% CI) 1.25 to 3.80) or lineman (OR 1.59; 95% CI 1.18 to 2.14), whereas a decreased OR was found for power plant operators (OR 0.67; 95% CI 0.33 to 1.40). A dose response gradient with exposure to magnetic fields was found for exposure in the previous year, with a mortality OR of 1.70 (95% CI 1.00 to 2.90) in the highest exposure category. Stronger associations, with ORs in the range of 2.12-3.62, were found for men <50 years of age. CONCLUSION: These data provide evidence for an association between occupational electromagnetic fields and suicide that warrants further evaluation. A plausible mechanism related to melatonin and depression provides a direction for additional laboratory research as well as epidemiological evaluation.

West J Med 2000 Aug;173(2):94-100
Exposure to electromagnetic fields and suicide among electric utility workers: a nested case-control study.

van Wijngaarden E, Savitz DA, Kleckner RC, Cai J, Loomis D.

Department of Epidemiology, University of North Carolina, School of Public Health CB 7400, Chapel Hill, NC 27599-7400, USA.

OBJECTIVE: To examine mortality from suicide in relation to estimated exposure to extremely low-frequency electromagnetic fields in a cohort of 138,905 male electric utility workers. METHODS: Case-control sampling, which included 536 deaths from suicide and 5, 348 eligible controls. Exposure was classified based on work in the most common jobs with increased exposure to magnetic fields and indices of cumulative exposure to magnetic fields based on a measurement survey. RESULTS: Suicide mortality was increased relative to work in exposed jobs and with indices of exposure to magnetic fields. Increased odds ratios (ORs) were found for years of employment as an electrician (OR, 2.18; 95% confidence interval [CI], 1.25-3.80) or line worker (OR, 1.59; 95% CI, 1.18-2.14), whereas a decreased OR was found for power plant operators (OR, 0.67; 95% CI, 0.33-1.40). A dose-response gradient with exposure to magnetic fields was found for exposure in the previous year, with a mortality OR of 1.70 (95% CI, 1.00-2.90) in the highest exposure category. Stronger associations, with ORs in the range of 2.12 to 3.62, were found for men younger than 50 years. CONCLUSIONS: These data provide evidence for an association between occupational electromagnetic fields and suicide that warrants further evaluation. A plausible mechanism related to melatonin and depression provides a direction for additional laboratory research and epidemiologic evaluation.

Am J Epidemiol 1997 Dec 15;146(12):1037-45
Magnetic fields of transmission lines and depression.

Verkasalo PK, Kaprio J, Varjonen J, Romanov K, Heikkila K, Koskenvuo M.

Department of Public Health, University of Helsinki, Finland.

Electromagnetic fields have been suggested to contribute to the risk of depression by causing pineal dysfunction. Some epidemiologic studies have supported this possibility but have generally reported crude methods of exposure assessment and nonsystematic evaluation of depression. Using two available nationwide data sets, the authors identified from the Finnish Twin Cohort Study 12,063 persons who had answered the 21-item Beck Depression Inventory of self-rated depressive symptoms in 1990. The personal 20-year histories of exposure (i.e., distance and calculated annual average magnetic fields) before 1990 to overhead 110- to 400-kv power lines were obtained from the Finnish Transmission Line Cohort Study. The adjusted mean Beck Depression Inventory scores did not differ by exposure, providing some assurance that proximity to high-voltage transmission lines is not associated with changes within the common range of depressive symptoms. However, the risk of severe depression was increased 4.7-fold (95% confidence interval 1.70-13.3) among subjects living within 100 m of a high-voltage power line. This finding was based on small numbers. The authors recommend that attempts be made to strive for a better understanding of the exposure characteristics in relation to the onset and course of depression.

Med Pr 1997;48(5):495-505
Neurotic disturbances, depression and anxiety disorders in the population living in the vicinity of overhead high-voltage transmission line 400 kV. Epidemiological pilot study [Article in Polish]

Zyss T, Dobrowolski JW, Krawczyk K.

Katedry Psychiatrii, Collegium Medicum Uniwersytetu Jagiellonskiego w Krakowie.

Numerous reports suggest a relationship between the increased incidence of depressive and neurotic symptoms in humans and the exposure to extremely low frequency electromagnetic field (EMF) at the place of residence. Our study was conducted in one of the Cracow suburbs with low socio-economic status, adjacent to an easement containing two 400 kV high-voltage transmission lines (distance up to 50 m from the line). The population investigated comprised 70 persons (35 males and 35 females). This group was exposed to EMF from 1986. A control group (n = 37), non-exposed to EMF, was also tested. The EMF intensity was measured by special devices. The following assessments instruments were used: Anamnestic Data Questionnaire, Neurotic Symptoms Questionnaire "O" Spielberger Self-Rating Questionnaire, and Beck-Self-Rating Scale. The measurements of the electric field levels taken at the front walls of investigated buildings averaged much higher than normal values of safety exposure. Our investigation showed the increased psychopathological values in all clinical tests. The difference between the group exposed to EMF and the control population was statistically significant. The results of our study did not support a possible cause-and-effect relationship between EMF and psychopathology observed. Some other factors (noise) can be responsible for the data obtained. The hypothesis that EMF produced by external electric power lines may enhance the occurrence of neurotic symptoms and depression, requires further clinical and experimental investigations.

Psychiatr Pol 1999 Jul-Aug;33(4):535-51
Epidemiological studies on neurotic disturbances, anxiety and depression disorders in a population living near an overhead high voltage transmission line (400 kV) [Article in Polish]

Zyss T.

Katedry Psychiatrii Collegium Medicum UJ w Krakowie. mzzyss@cyf-kr.edu.pl

Epidemiological studies indicate an increased incidence of depression and neurotic disorders in persons long exposed to influence of electromagnetic fields. The examinations covered a selected population of several suburban neighborhoods of Cracow living not farther than 50 m from a 400 kV high-voltage transmission line. A group of 70 persons (35 men and 35 women) living near the transmission line for longer than 10 years was examined. A control group consisted of 37 persons not subjected to an influence of similar transmission line. Instruments used in the examination included: Symptom Checklist "0", Spielberge's Self-assessment Questionnaire and Beck's Inventory. Also, a modified life-history questionnaire was applied. In the examined households we found significantly increased values of intensity of the electric component (by the so-called "ecological" Swedish norms). The population resident in the closest neighborhood of the examined transmission-line manifested high level of psychopathology, significantly different than that in the control group. However, the obtained results do not allow us to state univocally whether the observed psychopathology remains in causal nexus with the exposure to electromagnetic field. Other factors, like noise, may also be responsible for these results. The hypothesis that electromagnetic fields generated by high-voltage transmission lines may evoke depressive disorders and depression requires further clinical and experimental studies.