Higher methadone dose reduces risky drug injecting behaviours among methadone clients in Myanmar

Background

HIV prevalence rate among people who inject drugs (PWIDs) in Myanmar is marginally high (34.9%). HIV transmission can be reduced and prevented through harm reduction programs such as methadone maintenance treatment (MMT) and needle syringe exchange program (NSEP). We sought to determine the relationship between methadone dose and injecting behaviours among clients enrolled in the MMT program in Myanmar.

Method

A total of 210 MMT clients, who had a minimum of six-month methadone treatment history, were recruited from five cities through stratified random sampling for this cross-sectional study. A semi-structured questionnaire with the timeline flow back (TLFB) scale was administered. Respondents were also screened for illicit drug use.

Results

Almost two-thirds (63.5%, n=132) received less than or equal to 80mg/day of methadone dose, and 36.5% (n=76) received more than 80mg of methadone daily, while the sample average daily methadone dose in this study was 83mg (ranging from 20mg to 300mg per day). The results indicated that methadone dose was associated with having HIV infection, antiretroviral therapy (ART) and tuberculosis (TB) treatment history, heroin injection history in the last 30 days, needle sharing history, addiction severity on employment, as well as THC (cannabis) and benzodiazepine use history (p<0.05). In addition, those who received a high methadone dose (more than 80mg/day) reduced their heroin injection use by 4 times compared to heroin injection frequency of respondents on low methadone dose (injection IRR=0.0029 vs. 0.0118, p=0.0000). Meanwhile, those who had HIV on high methadone dose were 2.6 times more likely to report reduction in risky injecting behaviours compared to low methadone dose.

Conclusion

A higher dose of methadone on prescription (more than 80mg/day) seems to reduce risky HIV injecting behaviours among both HIV negative and positive clients in MMT programs in Myanmar.