title: Environmental risk factors and amyotrophic lateral sclerosis (ALS): a case-control study of ALS in Michigan.
abstract: An interim report of a case-control study was conducted to explore the role of environmental factors in the development of amyotrophic lateral sclerosis (ALS). Sixty-six cases and 66 age- and gender-matched controls were recruited. Detailed information regarding residence history, occupational history, smoking, physical activity, and other factors was obtained using questionnaires. The association of ALS with potential risk factors, including smoking, physical activity and chemical exposure, was investigated using conditional logistic regression models. As compared to controls, a greater number of our randomly selected ALS patients reported exposure to fertilizers to treat private yards and gardens and occupational exposure to pesticides in the last 30 years than our randomly selected control cases. Smoking, occupational exposures to metals, dust/fibers/fumes/gas and radiation, and physical activity were not associated with ALS when comparing the randomly selected ALS patients to the control subjects. To further explore and confirm results, exposures over several time frames, including 0-10 and 10-30 years earlier, were considered, and analyses were stratified by age and gender. Pesticide and fertilizer exposure were both significantly associated with ALS in the randomly selected ALS patients. While study results need to be interpreted cautiously given the small sample size and the lack of direct exposure measures, these results suggest that environmental and particularly residential exposure factors warrant close attention in studies examining risk factors of ALS.
authors: Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan, United States of America.
authors: Yu
authors: Y
authors: Yu
authors: Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan, United States of America.
authors: Feng-Chiao
authors: FC
authors: Su
authors: Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America.
authors: Brian C
authors: BC
authors: Callaghan
authors: Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America.
authors: Stephen A
authors: SA
authors: Goutman
authors: Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan, United States of America.
authors: Stuart A
authors: SA
authors: Batterman
authors: Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America.
authors: Eva L
authors: EL
authors: Feldman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000453:epidemiology*; D016022:Case-Control Studies; D003710:Demography; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D008824:Michigan / Q000453:epidemiology; D008875:Middle Aged; D009043:Motor Activity; D012044:Regression Analysis; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects