There is now evidence from a wide variety of geographic areas that many intravenous drug users will change their behavior in order to reduce their risk of developing AIDS. There is even evidence from some areas that the behavior change has led to relative stabilization of seroprevalence rates, although longer-term studies will be needed to establish this definitively. AIDS behavior change in the area of sexual risk reduction appears to be much more difficult than change of drug injection behavior. Conceptual models of AIDS-related behavior change are needed, particularly models that can incorporate the injection of different drugs and variation in social and psychological characteristics among drug injectors. There is increasing evidence for a wider spectrum of HIV-related morbidity and mortality among intravenous drug users than is captured by the current surveillance definition for AIDS, again emphasizing the need for effective prevention programs.
PIP: Topics concerning intravenous drug use and AIDS are reviewed. Topics include seroprevalence of HIV among users worldwide, evidence that iv drug users will alter behavior to avoid AIDS, results of safer injections programs, no evidence for reduction in high-risk behavior regarding sexual transmission of AIDS by users, diversity in HIV prevalence among users, and clinical aspects of their disease. Seroprevalence of HIV among drug users has remained at about 30% in the U.S. and parts of Europe, while lower in Asia and South America. There is now evidence from several places in Europe and the U.S. that many iv drug users will change drug injecting behavior to avoid AIDS. A conceptual model of new social norms needed to change behavior involves 3 stages: knowing the dangers of AIDS, having the means to change behavior (treatment or clean syringes), and a mechanism to reinforce the new behavior (perceived efficacy or social approval). There is no evidence that safer injection programs either keep users from going to treatment or increase numbers of users. In contrast, there is no evidence for improved sexual risk-taking behaviors among users, a fact which argues for stronger efforts to prevent already infected users from spreading HIV. The public, policy-markers, and researchers are unaware that seroprevalence of HIV varies with the type of drug injected (cocaine; heroin; amphetamine), and with socioeconomic status of the user (ethnic minority; majority). The clinical presentation, infection rate, persistence of infection, and mortality rate among iv drug users differs from that of the general AIDS population. Endocarditis, tuberculosis and bacterial pneumonias are 3 of the common findings in drug users. Even "non-AIDS" deaths apparently due to immunosuppression are reported in drug users. There may be undiscovered co-factors in HIV infection in this population.