Faculty Bibliography

OBJECTIVE: This study assessed the relationship between self-reported acquired immunodeficiency syndrome (AIDS) behavioral change and human immunodeficiency virus (HIV) serostatus among injection drug users. METHODS: The study sample involved 4419 injection drug users recruited from drug abuse treatment and nontreatment settings in 11 cities in North America, South America, Europe, Asia, and Australia. The World Health Organization multisite risk behavior questionnaire was used, and either blood or saliva samples for HIV testing were obtained. Subjects were asked, "Since you first heard about AIDS, have you done anything to avoid getting AIDS?" RESULTS: The protective odds ratio for behavioral change against being infected with HIV was 0.50 (95% confidence interval = 0.42, 0.59). While there was important variation across sites, the relationship remained consistent across both demographic and drug use history subgroups. CONCLUSIONS: Injection drug users are capable of modifying their HIV risk behaviors and reporting accurately on behavioral changes. These behavioral changes are associated with their avoidance of HIV infection.

BACKGROUND: There have been no studies showing that participation in programmes which provide legal access to drug-injection equipment leads to individual-level protection against incident HIV infection. We have compared HIV incidence among injecting drug users participating in syringe-exchange programmes in New York City with that among non-participants. METHODS: We used meta-analytic techniques to combine HIV incidence data from injecting drug users in three studies: the Syringe Exchange Evaluation (n = 280), in which multiple interviews and saliva samples were collected from participants at exchange sites; the Vaccine Preparedness initiative cohort (n = 133 continuing exchanges and 188 non-exchangers, in which participants were interviewed and tested for HIV every 3 months; and very-high-seroprevalence cities in the National AIDS Demonstration Research (NADR) programme (n = 1029), in which street-recruited individuals were interviewed and tested for HIV every 6 months. In practice, participants in the NADR study had not used syringe exchanges. FINDINGS: HIV incidence among continuing exchange-users in the Syringe Exchange Evaluation was 1.58 per 100 person-years at risk (95% CI 0.54, 4.65) and among continuing exchange-users in the Vaccine Preparedness Initiative it was 1.38 per 100 person-years at risk (0.23, 4.57). Incidence among non-users of the exchange in the Vaccine Preparedness Initiative was 5.26 per 100 person-years at risk (2.41, 11.49), and in the NADR cities, 6.23 per 100 person-years at risk (4.4, 8.6). In a pooled-data, multivariate proportional-hazards analysis, not using the exchanges was associated with a hazard ratio of 3.35 (95% CI 1.29, 8.65) for incident HIV infection compared with using the exchanges. INTERPRETATION: We observed an individual-level protective effect against HIV infection associated with participation in a syringe-exchange programme. Sterile injection equipment should be legally provided to reduce the risk of HIV infection in persons who inject illicit drugs