Environmental risk factors in siblings with Parkinson's disease
G. F. Wong, C. S. Gray, R. S. Hassanein and W. C. Koller
Department of Neurology, Kansas City 66103.
To investigate possible risk factors in Parkinson's disease, we conducted a
case-controlled study of 19 families having two or more siblings with
Parkinson's disease. Demographic data were collected, including lifetime
histories of places of residence; sources of drinking water; occupations,
such as farming; and exposure to herbicides and pesticides. Rural living
and drinking well water, but not farming and herbicide exposure, were
significantly increased in 38 parkinsonians compared with 38 normal control
subjects. A comparison of parkinsonian siblings with siblings with
essential tremor revealed no differences in any risk factors for the years
of shared environment. These data suggest that living in a rural
environment and drinking well water are risk factors for Parkinson's
disease and that the total life exposure to an environmental toxin may be
more important than exposure in early life.
