Parkinson's disease in Ferrara, Italy, 1967 through 1987
E. Granieri, M. Carreras, I. Casetta, V. Govoni, M. R. Tola, E. Paolino, V. C. Monetti and P. De Bastiani
Section of Neuroepidemiology, University of Ferrara, Italy.
Epidemiological surveys on Parkinson's disease that have been carried out
in different parts of the world have suggested that the disease is
uniformly distributed in white populations. The position with regard to the
Mediterranean peoples is still controversial, because of the large
variation of the frequencies observed in the different areas that have been
investigated. We therefore studied the frequency of Parkinson's disease in
the Local Health Service of Ferrara, northeastern Italy (mean population,
187,000). Based on 394 patients, the mean incidence per year for the period
from 1967 through 1987 was 10.01/100,000. The incidence rate of Parkinson's
disease among cases with early onset was found to be statistically higher
in rural areas as compared with urban ones (6.32/100,000 vs 3.11/100,000).
Moreover, the study revealed a significantly higher incidence rate among
agricultural workers (20.6/100,000). These results would seem to give
further support to the hypothesis of a possible causal role of
environmental factors that are mainly linked to agriculture, most likely
due to the continual exposure to toxic agents in this area. However,
further studies, which are not exclusively epidemiological, are necessary
before any conclusions may be drawn, because many confounding variables may
account for the results from surveys of this type.
