An observational study on high-risk behaviour and treatment adherence among injecting drug users attending an opioid substitution therapy centre in a teaching institution of Kolkata.

Objectives: Despite receiving opioid substitution therapy (OST), injectable drug consumption is not uncommon among the injecting drug users (IDUs) that increases the risk of contracting HIV. The current study was aimed at exploring the injection related and sex related high-risk behaviour among IDUs, choices of injectable opioids consumed and treatment adherence. Materials and Methods: An observational study was conducted among 168 IDUs attending the OST centre. Structured questionnaire included sociodemographic characteristics, high-risk behaviour as well as injectable opioids consumption. Descriptive statistics were used to summarize the data. Results: Nearly 30% of the IDUs were engaged in injecting practice while on OST. Of 143 male IDUs, 5.6% of the clients had had sex with commercial sex worker, whereas 3.5% of them had multiple partners. Four of 143 men were MSM, whereas 32 IDUs had sex without condom in the preceding 1 year. Regarding treatment adherence, 62.9% IDUs were very regular. As far as the retention rate was concerned, the findings were promising, i.e. 77.8% at the end of 3 months and 70.7% at the end of 6 months. Buprenorphine was the commonest opioid consumed by the IDUs before attending the OST centres while heroine used to be drug of choice when they first started injecting. Conclusion: The study revealed high-risk behaviour of IDUs attending an OST centre. The study provided useful information about the choices of opioids injected by the IDUs. The findings of the study might be of help in designing appropriate strategies for the improvement of treatment adherence among IDUs.