HIV infection risk behaviors and methadone treatment: Client-reported HIV infection in a follow-up study of injecting drug users in New England

There is wide variation in reported risk factors for HN incidence among injecting drug users by community. Available HIV seroprevalence and incidence data indicate that nearly 60% of HIV infection is associated with injecting drug use in Connecticut and 48% in Massachusetts. Using 12-month follow-up data on 354 initially HIV-negative New England (Massachusetts and Connecticut) methadone treatment clients, we assessed the association between baseline drug use practices, sexual behavior, partner behaviors, and client-reported HIV infection during follow-up. Variables that predicted client-reported positive HN antibody test results were modeled by Cox proportional hazards regression. HN infection among those tested was 14.2 per 100 person years (PY) [95% Confidence interval (CI) = 9.5 to 21.3] For each injection the relative risk (RR) was 1.1 (95% CI = 1.1 to 1.2), for males 3.0 (95% CI = 1.2 to 7.3), for blacks 5.0 (95% CI = 1.6 to 15.5), for Hispanics 3.6 (95% CI = 1.2 to 10.5). Men who used more than one unclean needle per day and had an HN-infected steady partner had an RR of 28.4 (95% CI = 4.4 to 176.4). For women, using speedball (RR = 6.1, 95% CI = 1.2 to 38.8) and being black (RR = 4.4, 95% CI = 1.0 to 19.8) predicted self-reported HIV infection; having a steady partner who ever injected increased this risk substantially (RR = 65.3, 95%, CI = 4.0 to 1046.5). These findings for IDUs in Massachusetts and Connecticut indicate that risk factors for HIV infection for men are consistent with expected transmission by unclean needles with an HIV-infected partner, but a preference for using speedball predicted HIV infection among women IDUs.