Association between hepatitis C virus infection and subsequent chronic inflammatory skin disease.

Hepatitis C virus (HCV) infection is associated with several cutaneous manifestations, including lichen planus and psoriasis. However, its association with other chronic inflammatory skin diseases (CISD) remains largely unknown. The aim of this study was to investigate the association between HCV infection and CISD. Participants were recruited from the National Health Insurance Research Database in Taiwan. Altogether 23 509 patients with HCV infection and 94 036 matched controls were included to assess the risk of CISD. A Cox regression model was used for the analyses. Compared with controls, patients with HCV infection had an adjusted hazard ratio (aHR) of 6.34 (95% confidence interval [CI], 5.30-7.58) for CISD after adjustment for potential confounders. Regarding individual CISD, patients with HCV infection had a significantly increased risk of developing lichen planus, psoriasis, vitiligo, alopecia areata, and cutaneous lupus erythematosus. Interferon-based antiviral therapy (IFN-based AVT) was significantly associated with a decreased risk of CISD (aHR = 0.42; 95% CI, 0.28-0.64). Patients with HCV infection had a significantly increased risk of CISD, while IFN-based AVT was associated with a decreased risk. These findings suggest monitoring of CISD in patients with HCV infection.