Objective: To examine the trends in HIV incidence among street-recruited injection drug users (IDUs) in San Francisco from 1986 through 1997. Methods: IDUs were recruited in three San Francisco neighborhoods using targeted sampling techniques in 22 semiannual, cross-sectional waves. Respondents who were HIV antibody seronegative at their first visit and participated in more than one cross-section were analyzed longitudinally (N=1,651). Intervals between last negative and first positive HIV tests were often more than a year (49%). Methods for interval-censored data were therefore used to model risk of seroconversion as a smooth function of time. Annualized HIV incidence rates were calculated for each half-year interval, adjusting for number of previous visits as a time-dependent covariate to control possible participation bias. Results: Of 1,651 IDUs, 51% were African American, 32% white, 12% Latino, and 5% other ethnicities; 66% were men; median age was 40 years (inter-quartile range 34, 44); 40% considered themselves homeless. 70 IDUs seroconverted. Modeled HIV incidence declined steadily from 3.8% in 1986 (95% Confidence Interval=1.7, 8.4) to 1.0% in 1992 (95% Confidence Interval=0.7, 1.6), then started increasing slowly in 1995 to 1.6% in 1998 (95% confidence interval=0.7, 3.7). These estimates did not differ significantly when controlling for neighborhood or gender. Conclusions: HIV incidence among IDUs in San Francisco has declined since the late 1980's, but appears to have remained above 1% per year in the late 1990's. This indicates an ongoing need for HIV prevention measures focusing specifically on IDUs who are engaging in risky behaviors.
Learning Objectives: At the conclusion of the session, the participant will be able to: 1. Understand the trends of HIV incidence among injection drug users in San Francisco from 1986 through 1997. 2. Describe the HIV epidemic among injection drug users in San Francisco from 1986 to 1997. 3. Assess the urgency of HIV prevention among injection drug users
Keywords: Injection Drug Users, HIV/AIDS
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.