Hepatitis C virus infection as a risk factor for Parkinson disease: A nationwide cohort study

Interesting observation... I don't remember seeing this before...

Neurology. 2015 Dec 23. pii: 10.1212/WNL.0000000000002307. [Epub ahead of print]

Tsai HH, Liou HH, Muo CH, Lee CZ, Yen RF, Kao CH.

OBJECTIVE:

To determine whether hepatitis C virus (HCV) infection is a risk factor for developing Parkinson disease (PD).

METHODS:

This nationwide population-based cohort study was based on data obtained from a dataset of the Taiwan National Health Insurance Research Database for the period 2000 to 2010. A total of 49,967 patients with viral hepatitis were included for analysis. Furthermore, 199,868 people without viral hepatitis were included for comparisons. Patients with viral hepatitis were further grouped into 3 cohorts: hepatitis B virus (HBV) infection, HCV infection, and HBV-HCV coinfection. In each cohort, we calculated the incidence of developing PD. A Cox proportional hazards model was applied to estimate the risk of developing PD in terms of hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS:

The crude HRs for developing PD was 0.66 (95% CI = 0.55-0.80) for HBV infection, 2.50 (95% CI = 2.07-3.02) for HCV infection, and 1.28 (95% CI = 0.88-1.85) for HBV-HCV coinfection. The association between HCV and PD remained statistically significant after adjustments for age, sex, and comorbidities (adjusted HR = 1.29, 95% CI = 1.06-1.56).

CONCLUSIONS:

We conducted a large nationwide population-based study and found that patients with HCV exhibit a significantly increased risk of developing PD.