Correlates of HIV infection among young adult short-term injection drug users

Objectives: To identify risks associated with HIV infection among young adu lt shortterm injection drug users. Methods: Current injection drug users, between 18 and 29 years of age, were recruited through street outreach to participate in a cross-sectional surv ey of HIV prevalence by circumstances of drug injection initiation, HIV-rel ated risk behaviors, and a follow-up to estimate HIV incidence. Results: At enrollment, 33 (14.4%) of 229 participants were HIV-seropositiv e. Significant bivariate associations with HIV at the time injection drug u se was initiated included age less than or equal to 18 years, having recept ive anal sex with the person who assisted with initiation, and having two o r more 'trainers' before being able to self-inject. injecting risks positiv ely associated with HIV included cocaine or speedball (heroin and cocaine t ogether) injection versus heroin or amphetamine injection, injecting five o r more times per day, daily crack smoking, backloading, sharing needles at peak drug use, and not using a new needle for every injection. Sexual pract ices associated with HIV included reporting > 100 lifetime sex partners, a history of sexual assault, being gay or bisexual, and trading sex for money or drugs after starting to inject. In a multivariate model, trading anal s ex for money or drugs after initiating injection drug use [odds ratio (OR), 14.2; 95% confidence interval (CI) 3.2-62.3], cocaine/speedball injection (OR, 10.3; 95% CI, 2.2-47.9), daily crack smoking (OR, 4.2; 95% CI, 1.7-10. 5), and having two or more trainers (OR, 2.6; 95% CI, 1.1-5.9) were indepen dently associated with HIV. During 12 months of follow-up, four persons ser oconverted for HIV (annual incidence: 2.6%; 95% CI, 1.1-5.9%) Conclusions: Among short-term injectors, both sexual and injecting practice s were important predictors of HIV infection, indicating that a proportion of HIV infections among young injection drug users can be attributed to sex ual transmission. The incidence rate for HIV infection suggests that immedi ate steps should be taken to prevent new infections among young injection d rug users. (C) 2000 Lippincott Williams & Wilkins.