Parkinson's disease mortality among male anesthesiologists and internists.

Clusters of Parkinson's disease (PD) among healthcare professionals have been interpreted as evidence of an infectious etiology. Anesthetic gases have also been associated with parkinsonism symptoms and PD among patients undergoing general anesthesia. We investigated PD mortality among large cohorts of male U.S. anesthesiologists (n = 33,040) and internal medicine physicians (n = 33,044). PD mortality for any mention on a death certificate was lower than rates in U.S. men during 1979-1995 for both groups, although anesthesiologists had a significantly elevated risk for PD as underlying cause of death for 10-year follow-up. Direct comparisons of mortality between the two cohorts indicated excess PD mortality in anesthesiologists for >10-year follow-up for any mention and for underlying cause of death. These findings lend some support to the hypothesis that infectious agents or anesthetic gases may be associated etiologically with PD.