Analysis of Different Types of Interferon-Associated Retinopathy in Patients with Chronic Hepatitis C Virus Infection Treated with Pegylated Interferon Plus Ribavirin

This retrospective cohort study aims to investigate interferon (IFN)-associated retinopathy incidence in patients with chronic hepatitis C virus (HCV) infection treated with pegylated interferon (PegIFN) plus ribavirin (RBV). We selected 1688 patients undergoing PegIFN/RBV therapy for HCV (HCV-treated cohort), 3376 patients not receiving HCV treatment (HCV-untreated cohort) and 16,880 controls without HCV (non-HCV cohort) from the Taiwan Longitudinal Health Insurance Database. The patients were frequency-matched by age, sex, and index date at a 1:2:10 ratio, and followed up until the end of 2013. Cox proportional hazard regression models were used to compare the incidences of any retinal vascular events, including subtypes, among the three cohorts. Compared with the non-HCV cohort, the HCV-treated cohort had a significantly increased risk of retinopathy (hazard ratio (HR) = 4.98, 95% confidence interval (CI): 2.02-12.3). The risk was particularly prominent for retinal hemorrhage (HR = 12.7, 95% CI: 3.78-42.9). When the HCV-untreated cohort was used as the reference, the aforementioned HRs increased to 9.02 (95% CI: 3.04-26.8) and 32.3 (95% CI: 3.94-265), respectively. This study suggested that PegIFN/RBV therapy significantly increased the risk of retinal hemorrhage but not retinal vascular occlusions in the HCV-treated cohort.