Linkage to hepatitis C virus care in a binational cohort study of People who inject drugs on the U.S.-Mexico border

Background: People who inject drugs (PWID) experience high rates of Hepatitis C Virus (HCV) infection in the U.S.-Mexico border region, but their care continuum is poorly characterized. Methods: We analysed the HCV care continuum (linkage to care, initiation and completion of treatment) in a cohort of PWID in Tijuana, Mexico and San Diego. We also used multivariable Poisson regression to identify factors associated with linkage to HCV care among PWID in San Diego and Tijuana who reported prior HCV diagnosis. Results: Among 133 PWID with active HCV infection in San Diego, 50.4 %, 16 % and 14.3 % reported prior awareness of their diagnosis; linkage to care and treatment completion; corresponding proportions for 21 PWID in Tijuana were 19 %, 14.3 % and 0 %. In multivariable analysis, factors independently associated with increased linkage to HCV care included receiving medication for opioid use disorder (MOUD) (Adjusted Prevalence Ratio [adjPR] 1.38; 95 % CI: 1.23–1.54) and HIV-seropositivity (adjPR 1.87 (95 %CI: 1.32–2.66). Tijuana residency (adjPR: 0.73; 95 % CI: 0.70–0.75) and younger age (adjPR 0.94 per 5-year age decrease; 95 % CI: 0.89–0.99) were independently associated with decreased linkage to care. Among PWID with a prior HCV diagnosis, 52.6 % and 40.7 % reported linkage to care in San Diego and Tijuana respectively. Conclusions: Our study shows poor linkage to HCV-related care among PWID in both San Diego and Tijuana, along with low treatment completion. MOUD programs could be an efficient touchpoint to improve access to HCV care.