Faculty Bibliography

This article estimates the population prevalence of current injection drug users (IDUs) in 96 large US metropolitan areas to facilitate structural analyses of its predictors and sequelae and assesses the extent to which drug abuse treatment and human immunodeficiency virus (HIV) counseling and testing are made available to drug injectors in each metropolitan area. We estimated the total number of current IDUs in the United States and then allocated the large metropolitan area total among large metropolitan areas using four different multiplier methods. Mean values were used as best estimates, and their validity and limitations were assessed. Prevalence of drug injectors per 10,000 population varied from 19 to 173 (median 60; interquartile range 42-87). Proportions of drug injectors in treatment varied from 1.0% to 39.3% (median 8.6%); and the ratio of HIV counseling and testing events to the estimated number of IDUs varied from 0.013 to 0.285 (median 0.082). Despite limitations in the accuracy of these estimates, they can be used for structural analyses of the correlates and predictors of the population density of drug injectors in metropolitan areas and for assessing the extent of service delivery to drug injectors. Although service provision levels varied considerably, few if any metropolitan areas seemed to be providing adequate levels of services.

Issues of cost and complexity have limited the study of the population sizes of men who have sex with men (MSM) and injection drug users (IDUs), two groups at clearly increased risk for human immunodeficiency virus (HIV) and other acute and chronic diseases. We developed a prototypical, easily applied estimation model for these populations and applied it to Miami, Florida. This model combined HIV prevalence estimates, HIV seroprevalence rates, and census data to make plausible estimates of the number and proportion of MSM and IDUs under a number of assumptions. Sensitivity analyses were conducted to test the robustness of the model. The model suggests that approximately 9.5% (plausible range 7.7%-11.3%) of Miami males aged 18 years or older are MSM (point estimate, N = 76,500), and 1.4% (plausible range 0.9%-1.9%) of the total population aged 18 years or older are IDUs (point estimate, N = 23,700). Males may be about 2.5 times more likely than females to be IDUs. The estimates were reasonably robust to biases. The model was used to develop MSM and IDU population estimates in selected urban areas across Florida and should be replicable in other medium-to-large urban areas. Such estimates could be useful for behavioral surveillance and resource allocation, including enhanced targeting of community-based interventions for primary and secondary HIV prevention.

AIMS/OBJECTIVE:To assess audio computer-assisted self-interviewing (A-CASI) as a mode of data collection with injecting drug users (IDUs) entering two drug treatment programs in New York City. A-CASI has been found to increase reporting of sensitive items among a variety of population subgroups. DESIGN/METHODS:A field test of A-CASI data collection conducted within an ongoing cross-sectional study of drug use and HIV risk behaviors among IDUs entering drug treatment. Participants were assigned without bias to either a computer-assisted interviewer-administered personal interview (CAPI) or to a mixed CAPI/A-CASI interview. In the latter, 'sensitive' portions (dealing with stigmatized behavior) of the questionnaire were self-administered through A-CASI, while the remaining portions were interviewer-administered. SETTING/METHODS:The Detoxification Program and the Methadone Maintenance Treatment Program (MMTP) at Beth Israel Medical Center in New York City. PARTICIPANTS/METHODS:Seven hundred and eighty-three IDUs entering drug treatment. MEASUREMENTS/METHODS:Odds ratios and adjusted odds ratios (controlling for demographic differences) for comparison of A-CASI versus CAPI responses on 111 sensitive questions. FINDINGS/RESULTS:Twenty-three statistically significant differences (each at P < 0.05), all in the direction of more reporting of the behaviors by the A-CASI group. Forty-one per cent of A-CASI participants said they would prefer any subsequent interviews to be fully A-CASI and 46% said they would prefer the mixed CAPI/A-CASI mode. CONCLUSIONS:A-CASI was associated with greater reporting of potentially stigmatized drug, sex and HIV risk behaviors on a moderate number of questions. Moreover, a large majority of participants who used A-CASI would like to be assigned to this method of data collection in future interviews.

"Intravention," prevention activities that are conducted by and sustained through ongoing actions of members of communities-at-risk, is an appropriate goal for HIV intervention activities. Data from 120 injection drug users in a Brooklyn, New York, neighborhood that has seen decreases in HIV prevalence among IDUs and little HIV diffusion to young adults indicate that most of them have recently (3 months) urged other people to engage in one or more self-protective actions. These data suggest that the common image of IDUs as simply being sources of social and medical problems is inaccurate. Research is needed into how to create and diffuse "communities of intravention; " and we suggest that behavioral interventions be evaluated for their success or failure at creating outward-focused health communication by participants as well as for their impact on individual risk behaviors.

OBJECTIVE: To assess recent developments in the HIV epidemic in injecting drug users (IDUs) in New York City. With >50,000 cases of AIDS in IDUs, New York has experienced the largest HIV/AIDS epidemic in IDUs of any city in the world. METHODS: Serial cross-sectional surveys conducted continuously from 1990 to 2001 of IDUs entering the Beth Israel Medical Center (BIMC) drug detoxification program in New York City. HIV serostatus, use of prevention services, and risk behaviors were measured. Individuals were permitted to participate multiple times in the surveys but not more than once in any year. RESULTS: Two thousand eight hundred eighty-seven individuals contributed 3100 observations from 1990 to 2001. There was a substantial and consistent decline in the prevalence of HIV infection among IDUs entering the BIMC detoxification program, from 54% (165/304) in 1991 to 13% (39/303) in 2001 (P < 0.0001). The decline was highly linear, with r2 = 0.92 and a slope of -3.7% in seroprevalence per year. The decline occurred for both males and females, both short and long-term IDUs, and the three largest racial/ethnic subgroups (all P < 0.001 by Cochran-Armitage testing). Use of HIV prevention services increased substantially, particularly syringe exchange and voluntary HIV counseling and testing. General reductions in injection risk behaviors occurred, but substantial numbers of IDUs continued to engage in both receptive and distributive syringe sharing. Two conditional types of risk reduction not currently recommended by health authorities were reported: "informed altruism," in which persons who knew that they were HIV seropositive reduced transmission behavior, and "partner restriction," in which persons who shared needles and syringes primarily confined this sharing within small social networks. CONCLUSIONS: HIV infection continues to decline in this population of IDUs in New York City, suggesting the possibility of bringing very high prevalence epidemics under control. Risk elimination may not be required; rather, multiple forms of risk reduction may be effective in reducing HIV transmission within a local population of IDUs.