Injection-Related Risk Behavior and Engagement in Outreach, Intervention and Prevention Services Across 20 US Cities.
Monitoring the effects of HIV prevention efforts on risk behaviors among persons who inject drugs is a key to inform prevention programs and policy. Using data from the 2012 National HIV Behavioral Surveillance interviews with persons who inject drugs across 20 US cities (n = 10,171), we conducted latent class analysis to identify injection risk classes and assess the relationship between engagement in prevention services and injection-related risk behavior. We conducted stratified analyses to examine the consistency of these associations across different geographical regions. The latent class analysis identified 6 distinct classes of injection-related risk behavior. The class structure was consistent across regions of the United States, but the distribution of risk classes varied significantly across regions. With covariate adjustment, the South had the most high-risk behavior (21%) and the Midwest had the least (6%). Participation in syringe access services and other prevention services was the lowest in the South. Syringe access was associated with a significantly lower likelihood of membership in the highest risk class in all regions except the Midwest. Participation in individual or group intervention with a practical skills component was associated with less risky injection behavior in all regions except the Northeast. Interventions that featured only safer injection information and discussion had no relationship with risk class. Our findings support evidence of the effectiveness of syringe service programs and safer injection skills training in reducing high-risk injection behavior and underscore the need to improve access to these prevention interventions in the South of the United States.