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.