Rural or urban living and Parkinson's disease

Henrique B. Ferraz, Luiz A. F. Andrade, Vítor Tumas, Leandro C. Calia, Vanderci Borges

Although the precise etiology of Parkinson's disease (PD) is as yet unknown, it appears that certain environmental factors are involved. Prior living in a rural area has been implicated as a possible risk factor for PD, particularly in the early onset type. We evaluated the role of previous living conditions in the clinical correlates and outcome characteristics of 118 PD patients. All of them were seen from January 1987 to October 1992. The Rural Group (RG) comprised 71 patients (60.2%) who had lived in the rural area for at least 10 years (mainly in early phase of life) and the Urban Group (UG) consisted of 47 patients (39.8%) who had lived their entire life in an urban environment. The average age at the beginning of the symptoms was 58.8 in the RG and 54.1 in the UG. The mixed form of the disease (tremor, rigidity and akinesia) was the most frequent in both groups. A minimum 6-month follow-up period was undertaken with 63 patients (average 20 months) and no difference in response to treatment or in progression of the illness was detected between the two groups. Our data show that the previous living environment does not appear to be a determining factor in either the clinical or outcome characteristics of PD.