Factors Associated With HIV Seroconversion Among Former Opiate Users Enrolled In The Methadone Maintenance Treatment

BackgroundVarious literatures have shown that methadone maintenance treatment (MMT) can effectively reduce opioid withdrawal syndromes and prevent blood-borne disease transmissions through intravenous drug use, such as human immunodeficiency virus (HIV). Nowadays, methadone is extensively used to treat patients with opioid dependency throughout the world. Since 2004, the Chinese government has established and rapidly expanded MMT programs all over the country in an effort to to reduce the transmission of HIV among intravenous drug users.Objectives1. To document incidence of HIV seroconversion among former opiate users enrolled in the MMT clinics.2. To analyze factors associated with HIV seroconversion among former opiate users enrolled in the MMT clinics.MethodsMedical records of 132,587 study subjects were abstracted from 452 MMT clinics with internet-based reporting out of all the 503 clinics established before December 31, 2007. Data was collected as a part of the Chinese Centers for Disease Control and Prevention's routine surveys and laboratory tests of MMT clinic patients. This study analyzed information regarding MMT clinic patients' demographic characteristics, former opiate using behaviors, HIV status and HIV seroconversion incidence among those who tested negative when they first enrolled in the MMT clinics. Descriptive analysis, univariate chi-square test, and multivariate logistic regression were performed for data analyses.Results1. Crude HIV-positive prevalence was 9.60% among former opiate users when they first enrolled in the MMT clinics. After taking into account variations of the HIV reporting rates among different provinces, the adjusted prevalence was 9.90%.2. The average incidence of HIV seroconversion was 0.77 case per 100 person-years after MMT clinic enrollment and lowered as the duration of treatment prolonged: from 1.07 cases per 100 person-years in the first six months to 0.09 case per 100 person-years after 18 months.3. The main factors associated with HIV seroconversion among former opiate users after MMT clinics enrollment included being unmarried (OR=1.63, 95% CI: 1.11-2.38), engaging in injection only behavior prior to MMT enrollment (OR=4.21, 95% CI: 2.18-8.13), sharing injection equipment prior to MMT enrollment (OR=1.87, 95% CI: 1.27-2.75), and HIV-positive prevalence of the particular enrolled MMT clinic (OR=1.05, 95% CI: 1.04-1.06).ConclusionsHIV-negative former opiate users enrolled in the MMT clinics may still seroconvert although their risk of HIV infection decreases as the time of enrollment in the MMT clinics increases. In addition, the risk is associated with the local drug user population's HIV infection rate and the MMT clinic patients' former drug using behaviors. Therefore efforts should be made to identify specific drug using behaviors prior to MMT clinic enrollment. Moreover, intervention programs should target patients who are more likely to seroconvert and focus on increasing retention rate in the MMT clinics since it may reduce new HTV infections.