Hepatitis C virus (HCV) infection & risk factors for HCV positivity in injecting & non-injecting drug users attending a de-addiction centre in northern India

BACKGROUND & OBJECTIVES: Injecting drug use is a major route of hepatitis C virus (HCV) infection in India, but there may be other risk factors also. This study was carried out to determine the seroprevalence of anti-HCV antibody in injecting drug users (IDUs) vs. non-IDUs (NIDUs), and to study the risk estimates for HCV seropositivity in the total sample of substance users with regard to various demographic, clinical, behavioural and personality factors. METHODS: The IDUs (n = 201) and NIDUs (n = 219) were assessed for demographic, clinical and behavioural information, and were rated on instruments for severity of dependence, risk behaviour and personality profiles. Anti-HCV antibody was tested by ELISA and confirmed by recombinant immunoblot assay (RIBA) test. RESULTS: Almost one-third of the IDUs (64 of 201; 31.8%) were positive for anti-HCV antibody, as opposed to only seven (3.2%) of the NIDUs. The four risk factors strongly associated with HCV positivity in multivariate analysis were sharing syringe [Exp(B) 75.04; 95%CI 18.28-307.96; P<0.001], reuse of injection accessories (16.39; 3.51-76.92; P<0.001), blood transfusion (5.88; 1.63-21.23; P=0.007) and IDU status (3.60; 1.26-10.31; P=0.017). Other variables less strongly but significantly associated with HCV positivity were multiple sex partners, opioid dependence, risk behaviour scores, impulsivity, and lower age of onset of drug use. INTERPRETATION & CONCLUSIONS: Our study showed a high seroprevalence of anti-HCV antibody in IDUs. In the substance users, HCV positivity was significantly and independently associated with several clinical, behavioural, and personality risk factors.