Drug use stigma and its association with active hepatitis C virus infection and injection drug use behaviors among community-based people who inject drugs in India

Background: Although drug use stigma is globally pervasive, quantitative evidence of its role in hepatitis C virus (HCV) transmission is limited. We evaluated the psychometric properties of a drug use stigma scale and examined the association between drug use stigma and active HCV infection among a community-based sample of people who inject drugs (PWID) in India. Methods: Between 8/2016 and 5/2017, a cross-sectional sample of PWID was recruited from 12 Indian cities (~1000/city) using respondent-driven sampling. Participants were ≥18 years old and reported injection drug use (IDU) in the past 2 years. Multivariable logistic regression with a random-intercept for each city was used to estimate adjusted odds ratios (aOR) of active HCV infection (RNA>30 IU/mL). Analyses incorporated RDS-II weights. Results: Of 11,663 participants, 73.1% reported IDU in the past 6 months and 33.8% had active HCV infection. Exploratory factor analysis yielded a four-factor solution of enacted, vicarious, felt normative and internalized drug use stigma with high internal consistency (Cronbach's α: 0.85–0.92). In analyses adjusted for age, gender, northeast region, education, homelessness, incarceration, alcohol dependence, HIV status, frequency of IDU, and ever sharing needles/syringes, PWID reporting any enacted stigma had greater odds of active HCV infection (aOR = 1.27 [95% CI = 1.13–1.43]) as did PWID with internalized stigma scores in the highest quartile (vs. lowest quartile; aOR = 1.69 [95% CI = 1.11–2.56]). Among PWID who reported IDU in the past 6 months, multiple forms of stigma were associated with higher frequency of IDU, sharing needles/syringes, having multiple injection partners, and IDU in public spaces. Conclusion: Using a multidimensional drug use stigma scale, various forms of stigma were significantly associated with active HCV infection and injection drug use-related risk behaviors. Collectively, these data suggest that drug use stigma may play a role in HCV transmission and impede efforts to achieve HCV elimination. Strategies to diminish drug use stigma are warranted.