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

FRANÇAIS :
Il y a une grande variation des facteurs de risques rapportés dans linfection au VIH parmi les usagers de drogues par voie intraveineuse selon les populations. La séroprévalence et lincidence au VIH montrent que près de 60 % des infections au VIH sont associées à lusage de drogues par voie intraveineuse dans le Connecticut et 48 % dans le Massachusets. Utilisant des données de suivi sur douze mois de patients initialement séronégatifs au VIH, les auteurs montrent lassociation entre les pratiques de lusage de drogues, le comportement sexuel, les comportements du partenaire et lapparition dune infection au VIH. Les facteurs de risque dinfection au VIH chez les hommes sont conséquents avec une transmission vraisemblable, par lusage de seringues usagées, la fréquentation dun ou dune partenaire infecté, lusage de speedball étant un facteur de risque élevé pour les femmes.
ENGLISH :
There is wide variation in reported risk factors for HIV incidence among injecting drug users by cominunity. Available HIV seroprevalence and incidence data indicate that nearly 60% of HIV infection is associated with injecting drug use in Connecticut and 48% in Massa- chusetts. 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 HIV antibody test results were modeled by Cox proportional hazards regression. HIV 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 HIV-infected steady partner had an RR of 28.4 (95% Cl = 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. (Author' s abstract)