Original Paper

Mortality from Neurodegenerative Disease and Exposure to Extremely Low-Frequency Magnetic Fields: 31 Years of Observations on Swiss Railway Employees
Martin Röösli^a, Manfred Lörtscher^b, Matthias Egger^{a, f}, Dominik Pfluger^c, Nadja Schreier^a, Emanuel Lörtscher^d, Peter Locher^e, Adrian Spoerri^a, Christoph Minder<sup>a

a</sup>Department of Social and Preventive Medicine, University of Berne, and
^bFederal Office of Transport, Berne,
^cdatametrix AG, Zurich,
^dLOITS, Bonstetten, and
^eENOTRAC AG, Uetendorf, Switzerland;
^fDepartment of Social Medicine, University of Bristol, Bristol, UK

Address of Corresponding Author

Neuroepidemiology 2007;28:197-206 (DOI: 10.1159/000108111)

  Key Words

• Electromagnetic fields
• Neurodegenerative diseases
• Amyotrophic lateral sclerosis
• Alzheimer's disease
• Parkinson's disease
• Multiple sclerosis
• Occupational exposure

  Abstract

Aims: The objective of the present study was to investigate the relationship between extremely low-frequency magnetic field (ELF-MF) exposure and mortality from several neurodegenerative conditions in Swiss railway employees. Methods: We studied a cohort of 20,141 Swiss railway employees with 464,129 person-years of follow-up between 1972 and 2002. For each individual, cumulative exposure was calculated from on-site measurements and modelling of past exposure. We compared cause-specific mortality in highly exposed train drivers (mean exposure: 21 µT) with less exposed occupational groups (for example station masters: 1 µT). Results: The hazard ratio for train drivers compared to station masters was 1.96 [95% confidence interval (CI) = 0.98-3.92] for senile dementia and 3.15 (95% CI = 0.90-11.04) for Alzheimer's disease. For every 10 µT years of cumulative exposure senile dementia mortality increased by 5.7% (95% CI = 1.3-10.4), Alzheimer's disease by 9.4% (95% CI = 2.7-16.4) and amyotrophic lateral sclerosis by 2.1% (95% CI = -6.8 to 11.7). There was no evidence for an increase in mortality from Parkinson's disease and multiple sclerosis. Conclusions: This study suggests a link between exposure to ELF-MF and Alzheimer's disease and indicates that ELF-MF might act in later stages of the disease process.

Copyright © 2007 S. Karger AG, Basel

  Author Contacts

Dr. Martin Röösli
Institut für Sozial- und Präventivmedizin
Finkenhubelweg 11
CH-3012 Bern (Switzerland)
Tel. +41 31 631 3867, Fax +41 31 631 3520, E-Mail Roeoesli@ispm.unibe.ch

  Article Information

Published online: September 11, 2007
Number of Print Pages : 10
Number of Figures : 3, Number of Tables : 5, Number of References : 31