Association of co-occurring mental health problems with hepatitis C status among young people who inject drugs in rural New Mexico, 2016–2018

BACKGROUND: Injection drug use (IDU) remains the strongest risk factor for hepatitis C virus (HCV) in the United States. HCV rates are increasing in rural areas among young adult people who inject drugs (PWID). People with HCV and PWID have disproportionate rates of mental health problems; however, it is unclear whether risky injection behaviors mediate the association between mental health problems and HCV. We examined the association between mental health problems and HCV in a rural cohort of young adult PWID, with the goal of informing rural service delivery. METHODS: We conducted a secondary analysis of cross-sectional data from a convenience sample of young adult PWID in 2 rural counties in New Mexico. Participants were recruited from 2 community venues between September 2016 and May 2018. Associations between mental health problems and HCV were examined using bivariate (Fisher’s exact) and multivariable modified Poisson regression analyses (with robust standard errors). Using structural equation modeling (SEM), we assessed duration of IDU and receptive syringe sharing (RSS) as mediators of this relationship. RESULTS: A total of 263 patients were enrolled, with a median age of 26.1 years. The majority were male (66.3%) and Hispanic/Latino (a) (87.6%). The median age first injected was 19 years, and over half reported having ever engaged in RSS (53.4%). At least one mental health problem was reported by 60.1% of participants, with post-traumatic stress disorder (PTSD) being the most prevalent condition (42.2%). A majority (60.9%) tested positive for HCV antibody, and just under half (45.7%) of all participants tested positive for HCV ribonucleic acid. In SEM, PTSD had a significant total effect on HCV (τ = 0.230, P = 0.05), and this relationship was partially mediated by duration of IDU (αβ = 0.077, P = 0.03). The association between mental health problems and HCV was partially mediated by duration of IDU and the sequential mediation of duration of IDU and RSS (αβ + αββ = 0.091, P = 0.05). CONCLUSIONS: High HCV rates among young adult PWID in rural New Mexico may be partly explained by mental health problems, duration of IDU and RSS. Mental health services for young adult PWID in rural areas may help decrease HCV transmission in rural areas. Trial Registration N/A. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13722-022-00340-3.