Injection Drug Use and Sexual Risk Behaviors Among People who Inject Drugs in Ukraine: A Random-Intercept Latent Transition Analysis.

HIV transmission in Ukraine is driven in part by unsafe injection drug use and sexual risk behaviors among people who inject drugs. We performed a random-intercept latent transition analysis on responses to 9 binary injection drug use and sexual behavior items from 1195 people who inject drugs with negative HIV status enrolled in a clustered randomized clinical trial of a social network intervention in Odessa, Donetsk, and Nikolayev, Ukraine. We identified 5 baseline classes: "Social injection/equipment-sharing" (11.7%), "Social injection" (25.9%), "High-risk collective preparation/splitting" (17.0%), "Collective preparation/splitting" (11.3%), and "Dealer-facilitated injection" (34.1%). After 12 months, intervention participants were more likely to transition to the "Collective preparation/splitting" class, which featured the fewest risk behaviors. Transitioning from the "Collective preparation/splitting" to the "Social injection/equipment-sharing" class was associated with HIV acquisition for control participants. Research to illuminate the stability of these patterns and how they may benefit from uniquely tailored programming to reduce unsafe behaviors is needed.