Association between viral hepatitis infection and Parkinson's disease: A population-based prospective study

The association between hepatitis virus infection and Parkinson's disease remains controversial. To determine whether hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are associated with an increased risk of Parkinson's disease in Korean aged >= 40 years, we completed a population-based prospective study including patients without infections and those with HBV, HCV and HBV/HCV infections from 2005 to 2015. We used the International Classification of Diseases 10th Revision to identify Parkinson's disease (G20) and chronic hepatitis C virus (B18.2) and chronic hepatitis B virus infections (B18.0 or B18.1). To identify Parkinson's disease risk, competing risk analysis adjusted for age, sex, comorbidities and death was performed. Overall, 1 010 317 patients (358 052, noninfection; 488 990, hepatitis B; 144 459 hepatitis C; and 18 680 hepatitis B/C) were included. The incidence density of Parkinson's disease per 10 000 person-years was highest in the hepatitis C group (8.0), followed by the hepatitis B/C (6.8) and hepatitis B (5.0) groups. Hypertension, ischaemic heart disease, epilepsy, stroke and depressive disorder increased the hazard of Parkinson's disease in all groups. The adjusted hazard ratios were 1.25 (95% confidence interval: 1.17-1.35), 1.39 (95% confidence interval: 1.27-1.52) and 1.46 (95% confidence interval: 1.14-1.85) in the HBV, HCV, and HBV/HCV groups, respectively. Our findings suggest that adult patient of 40 years and older with HBV and HCV infections should be monitored for signs of Parkinson's disease so that early intervention and accurate treatment can be provided for minimizing the development and consequences of Parkinson's disease.