Ethnic Disparities in Extrahepatic Manifestations Among People With HCV Infection: A Population-Based Study in British Columbia.

Background: Ethnic disparities in extrahepatic manifestations (EHMs) among individuals with chronic hepatitis C virus (HCV) infection are poorly understood, especially in diverse populations. We aimed to examine ethnic disparities in EHMs among individuals diagnosed with HCV in British Columbia (BC), Canada.

Methods: Using linked administrative health data from the BC Hepatitis Testers Cohort (1990-2015), we assessed EHMs incidence and risk by ethnicity (East Asian, South Asian, and Other) across 4 groups: individuals who remained untreated, pre-HCV treatment completion, post-HCV treatment completion, and those who spontaneously cleared HCV. EHMs included chronic kidney diseases (CKDs) and end-stage renal diseases (ESRDs), type 2 diabetes (T2DM), stroke, major adverse cardiac events (MACEs), and neurocognitive disorders. To assess the risk of EHMs by ethnicity, we used multivariable cause-specific proportional hazards models.

Results: Among 41 874 individuals, South and East Asians had higher incidence rates of CKD and ESRD, T2DM, stroke, and MACE compared with other ethnicities, particularly among untreated individuals. Adjusted analyses showed that untreated South Asians had significantly higher risk of CKD and ESRD (adjusted hazard ratio [aHR] 1.27, 95% confidence interval [CI] 1.02-2.16) and T2DM (aHR 2.12, 95% CI 1.53-2.94). Following HCV treatment, these disparities largely disappeared except for diabetes.

Conclusions: This study highlights the disproportionate burden of EHMs among Asians in BC and underscores the potential of HCV treatment to reduce ethnic disparities. Public health programming is needed to increase linkage to HCV treatment among those who remain untreated. Further research should focus on intra-ethnic differences and mechanisms underlying the impact of HCV treatment on mitigating these disparities.