Smoking and Parkinson's disease

A case-control analysis of Parkinson's disease and smoking habits was conducted in a cohort of 50,002 men who attended Harvard College (Cambridge, MA) or the University of Pennsylvania (Philadelphia, PA) between 1916 and 1950 and were followed in adulthood for morbidity and mortality data. Ninety-six cases of Parkinson's disease were identified from responses to a mailed questionnaire, addressed in 1976 to the University of Pennsylvania alumni and in 1977-1978 to the Harvard alumni. Four controls from the same population were selected for each case. Even though no statistically significant association was found, the results support a negative association between cigarette smoking and Parkinson's disease.