The effect of syringe exchange use on high-risk injection drug users: a cohort study.

OBJECTIVE: To determine whether syringe exchange program use is associated with cessation of syringe sharing among high-risk injection drug users. DESIGN AND METHODS: Between 1992 and 1996, street-recruited injection drug users were interviewed and received HIV testing and counseling semi-annually, as part of a dynamic cohort study. We examined a cohort of 340 high-risk injection drug users for whom two observations, 6-months apart, were available and who reported syringe sharing at the first interview. Multivariate logistic regression analysis was performed to determine the relationship between syringe exchange program use and cessation of syringe sharing, while controlling for confounding factors. RESULTS: At follow-up interview, 60% (204 of 340) reported quitting syringe sharing. High-risk injection drug users who began using the syringe exchange program were more likely to quit sharing syringes [adjusted odds ratio (AOR), 2.68; 95% confidence interval (CI), 1.35-5.33], as were those who continued using the syringe exchange program (AOR,1.98; 95% CI, 1.05-3.75) in comparison with non-syringe exchange program users, while controlling for confounding factors. CONCLUSIONS: The initiation and continuation of syringe exchange program use among high-risk injection drug users is independently associated with cessation of syringe sharing. Syringe exchange program use can be an important component in reducing the spread of blood-borne infectious diseases among high-risk injection drug users.

Risk factors among IDUs who give injections to or receive injections from other drug users.

AIMS: To assess risk factors associated with injection drug users (IDUs) who give injections to or receive injections from other IDUs. DESIGN AND SETTING: IDUs were recruited into a cross-sectional study using targeted sampling methods in Oakland, Richmond, and San Francisco, California from August 1996 to January 1997. "Street docs" are IDUs who reported having given injections to other IDUs in the past month. "Injection recipients" are IDUs who reported having received injections from other people in the past month. PARTICIPANTS: Of 1166 IDUs interviewed, 283 (24%) reported being injection recipients and 427 (37%) reported being street docs. MEASUREMENTS: Socio-demographic characteristics and injection-related risk behaviors. FINDINGS: Injection recipients and street docs were significantly more likely (p < 0.001) than other IDUs to report sharing syringes (33% of injection recipients, 21% of street docs and 7% of others), cookers (71% of injection recipients, 55% of street docs and 24% of others), rinse water (44% of injection recipients, 35% of street docs and 13% of others), and filters (60% of injection recipients, 47% of street docs and 20% of others). In a logistic regression model, injection recipients (adjusted odds ratio (AOR) = 4.29) and street docs (AOR = 1.91) were more likely than other IDUs to report having shared syringes. CONCLUSIONS: Giving and receiving injections is common among IDUs in the San Francisco Bay area. Qualitative and epidemiological studies are needed to understand better the infectious disease risks associated with giving and receiving injections. Interventions need to address these issues and provide practical solutions.

Use of an illegal syringe exchange and injection-related risk behaviors among street-recruited injection drug users in Oakland, California, 1992 to 1995.

OBJECTIVE: To determine factors associated with syringe and injection supply sharing among injection drug users (IDUs) in a community with an illegal underground syringe exchange program (SEP). METHODS: From 1992 to 1995, semiannual cross-sectional samples of IDUs were recruited in Oakland, California. To account for multiple observations from the same individual, we used general estimating equations with logit transformations to determine factors associated with sharing syringes and other injection supplies. RESULTS: 1304 IDUs were interviewed; 684 (53%) returned for more than one interview. 2830 interviews were available for analysis. SEP use increased and syringe and supply sharing declined from 1992 to 1995 among study participants. In multivariate analysis, SEP users were less likely to share syringes than non-SEP users (adjusted odds ratio [AOR] = 0.57; 95% confidence interval [CI] = 0.46-0.72). SEP use was not significantly associated with the sharing of injection supplies (AOR = 0.85; 95% CI = 0.68-1.07). Syringe sharing and injection supply sharing were significantly less likely to occur among African American and HIV-positive IDUs. CONCLUSIONS: These data suggest that illegal SEPs can be effective HIV prevention programs. Lower rates of syringe-based risk behaviors among African American and HIV-positive IDUs are encouraging.