Infections as a risk factor for Parkinson's disease: a case-control study.

Objectives: The etiology of Parkinson's disease (PD) is unknown. The aim of the study was to test the hypothesis that some infectious diseases are related to the occurrence of PD. Methods: The case-control study, conducted in Belgrade during the period 2001-2005, comprised 110 subjects diagnosed for the first time as PD cases, and 220 controls chosen among patients with degenerative joint disease and some diseases of the digestive tract. Results: According to logistic regression analysis, PD was significantly related to mumps [odds ratio adjusted on occupation and family history of PD (aOR) = 7.86, 95% confidence interval (CI) = 3.77-16.36], scarlet fever (aOR = 12.18, 95% CI = 1.97-75.19), influenza (aOR = 8.01, 95% CI = 4.61-13.92), whooping cough (aOR = 19.90, 95% CI = 2.07-190.66) and herpes simplex infections (aOR = 11.52, 95% CI = 2.25-58.89). Tuberculosis, measles and chicken pox were not associated with PD. Other infectious diseases we asked for were not reported (12 diseases), or were too rare (four diseases) to be analysed. Conclusion: The results obtained are in line with the suggestion that some infectious diseases may play a role in the development of PD.