Amyotrophic lateral sclerosis. A case-control study following detection of a cluster in a small Wisconsin community
D. G. Sienko, J. P. Davis, J. A. Taylor and B. R. Brooks
Bureau of Community Health and Prevention, Wisconsin Division of Health, University of Wisconsin School of Medicine, Madison.
From 1975 to 1983, six cases of amyotrophic lateral sclerosis (ALS) were
diagnosed in long-term residents of Two Rivers, Wis; the probability that
this occurred due to chance was less than .05. To investigate potential
risk factors for ALS, we conducted a case-control study using two control
subjects matched to each case patient for age, gender, and duration of
residence in Two Rivers. Physical trauma, the frequent consumption of
freshly caught Lake Michigan fish, and a family history of cancer were
reported more often by case patients than control subjects. These findings
support previous studies proposing a role for trauma in ALS pathogenesis
and suggest that the causative role of diet should be further explored.
Continued surveillance for and epidemiologic investigation of ALS clusters
with subsequent retrospective analysis may provide clues concerning the
cause of ALS.
