Spatial Distribution of Parkinson's Disease Prevalence in Québec by Hydrographic Region.

The association between environmental exposures and Parkinson's disease continues to garner interest. In the late 1980s, Barbeau et al. reported in the Canadian Journal of Neurological Sciences a heterogeneous distribution of Parkinson's disease cases across the province of Québec by hydrographic region. Here we report the findings of a validation study based on data obtained from the Québec medication insurance program-information which was unavailable to the previous group. Similar to Barbeau et al., our analysis showed a heterogeneous distribution of cases across the province with higher prevalence in the same region of interest, in addition to other areas.