Trends in human immunodeficiency virus infection among drug users in a detoxification unit.

In a cross-sectional study of 1111 injection drug users (IDUs) admitted to a hospital detoxification unit between 1987 and 2001, characteristics of substance abuse and blood samples were obtained at study entry. The median age at admission was 27 years, the median age at first injection of drugs was 19 years, and the median duration of injection drug use was 84 months. Overall prevalence of human immunodeficiency virus (HIV) infection was 60% (58% in men, 66% in women; P=.026). Age at start of and duration of injection drug use were associated with HIV infection (P<.001). The rate of HIV infection in persons with short duration of drug use (<24 months) was higher among women (45%) than among men (21%) (P=.002). The prevalence of HIV infection among IDUs <21 years old at first use of injection drugs and among patients reporting <48 months of injection drug use was significantly lower in those who started injection drug use after 1992 (19% vs. 53% of IDUs; odds ratio, 4.42; 95% confidence interval, 1.80-10.85). Awareness of acquired immunodeficiency syndrome, preventive measures, and substance abuse treatment have contributed to the stabilization of the HIV epidemic. The higher prevalence of HIV infection among women IDUs and among young IDUs who recently began injecting drugs emphasizes the need to target HIV-transmission risk reduction interventions early.