Correlates of shared methamphetamine injection among methamphetamine-injecting treatment seekers: the first report from Iran.

Shared methamphetamine injection is an emerging route of drug use among Iranian methamphetamine injectors. It is a primary vector for blood-borne infections. The aim of the current study is to determine the prevalence and correlates of shared methamphetamine injection in a sample of Iranian methamphetamine injecting treatment seekers in the south of Tehran. We surveyed male and female methamphetamine injectors at three drop-in centres and 18 drug-use community treatment programmes. Participants reported socio-demographic characteristics, drug use, high-risk behaviours, current status of viral infections and service use for drug treatment. Bivariate and multivariate logistic regression models were used to test associations between participants' characteristics and shared methamphetamine injection. Overall, 209 clients were recruited; 90.9% were male; 52.6% reported current methamphetamine injection without any shared injection behaviour and 47.4% reported current shared methamphetamine injection. Shared methamphetamine injection was found to be primarily associated with living with sex partners (AOR 1.25, 95% CI 1.13-1.98), reporting ≥3 years of dependence on methamphetamine injection (AOR 1.61, 95% CI 1.27-2.12), injection with pre-filled syringes in the past 12 months (AOR 1.96, 95% CI 1.47-2.42), homosexual sex without condom use in the past 12 months (AOR 1.85, 95% CI 1.21-2.25), the paucity of NA group participation in the past 12 months (AOR 0.67, 95% CI 0.41-0.99), the paucity of attending psychotherapeutic sessions in the past 12 months (AOR 0.44, 95% CI 0.28-0.96) and positive hepatitis C status (AOR 1.98, 95% CI 1.67-2.83). Deeper exploration of the relationship between shared methamphetamine injection and sexual risk among Iranian methamphetamine injectors would benefit HIV/sexually transmitted infection prevention efforts. In addition, existing psychosocial interventions for methamphetamine-injecting population may need to be adapted to better meet the risks of shared methamphetamine injectors.