Risk behavior and HIV infection among new drug injectors in the era of AIDS in New York City.

Objective: To examine HIV risk behavior and HIV infection among new initiates into illicit drug injection in New York City.

Design and methods: Cross-sectional surveys of injecting drug users (IDUs) recruited from a large detoxification treatment program (n=2489) and a street store-front research site (n=2630) in New York City from 1990 through 1996. Interviews covering demographics, drug use history, and HIV risk behavior were administered; serum samples were collected for HIV testing. Subjects were categorized into two groups of newer injectors: very recent initiates (just began injecting through 3 years) and recent initiates (injecting 4-6 years); and long-term injectors (injecting > or = 7 years).

Results: 954 of 5119 (19%) of the study subjects were newer injectors, essentially all of whom had begun injecting after knowledge about AIDS was widespread among IDUs in the city. New injectors were more likely to be female and white than long-term injectors, and new injectors were more likely to have begun injecting at an older age (median age at first injection for very recent initiates, 27 years; median age at first injection for recent initiates, 25 years; compared with median age at first injection for long-term injectors, 17 years). The newer injectors generally matched the long-term injectors in frequencies of HIV risk behavior; no significant differences were found among these groups on four measures of injection risk behavior. HIV infection was substantial among the newer injectors: HIV prevalence was 11% among the very recent initiates and 18% among the recent initiates. Among the new injectors, African Americans, Hispanics, females, and men who engaged in male-male sex were more likely to be infected.

Conclusions: The new injectors appear to have adopted the reduced risk injection practices of long-term injectors in the city. HIV infection among new injectors, however, must still be considered a considerable public health problem in New York City.