[Study on incidence of HIV infection among heroin addicts receiving methadone maintenance treatment in Dehong prefecture, Yunnan province].

OBJECTIVE

To determine the incidence and risk factors of HIV infection among heroin addicts receiving methadone maintenance treatment (MMT) in Dehong prefecture, Yunnan province.

METHODS

All heroin addicts who were HIV negative at the initiation of MMT in June 2005 and through June 2011, in Dehong prefecture were included in the cohort analysis. HIV incidence was calculated and related risk factors determined by using Cox proportional hazard regression model.

RESULTS

A total of 3154 MMT clinic attendants were qualified for this cohort study. By June 2011, 1023 (32.4%) of them had never received any follow-up HIV testing so were thus referred as loss to follow-up. The other 2131 (67.6%) members had received at least one follow-up HIV testing and were observed for a total of 4615.86 person-years. During the period, 22 new HIV infections or seroconverters were identified, making the overall HIV incidence as 0.48/100 person-years. The HIV incidence was higher among those who were unemployed, never married, self-reported being injecting drug users (IDUs) and HCV positive at entry into the MMT program. None of those who were always negative on follow-up-urine-testing of morphine was discovered as HIV newly infected during the follow-up period. Data from multiple regression analysis under Cox proportional hazard model indicated that after controlling for confounding variables, non-IDUs at the entry point for the MMT program, were less likely to be HIV newly-infected or seroconverted than IDUs (HR = 0.29, 95%CI: 0.11 - 0.76).

CONCLUSION

MMT program in Dehong prefecture was demonstrated to be fairly effective in reducing HIV transmission through drug use. Those HIV negative attendants at the MMT clinic who were IDUs or keep using drugs during the treatment, were at higher risk of HIV seroconvertion. More efforts were needed to improve the follow-up and HIV testing programs for the MMT clinic attendants.