Changes in sexual and drug-related risk behavior following antiretroviral therapy initiation among HIV-infected injection drug users.

OBJECTIVE To evaluate whether HAART is associated with subsequent sexual and drug-related risk behavior compensation among injection drug users (IDUs). DESIGN A community-based cohort study of 362 HIV-infected IDUs initiating HAART in Baltimore, Maryland. METHODS HAART use and risk behavior was assessed at 8316 biannual study visits (median 23). Using logistic regression with generalized estimating equations (GEE), we examined the effect of HAART initiation on changes in risk behavior while adjusting for sociodemographics, alcohol use, CD4 cell count, year of initiation and consistency of HAART use. RESULTS At HAART initiation, participants were a median of 44.4 years old, 71.3% men and 95.3% African-American. In multivariable analysis, HAART initiation was associated with a 75% reduction in the likelihood of unprotected sex [adjusted odds ratio (aOR) 0.25; 95% confidence interval (CI), 0.19-0.32] despite no change in overall sexual activity (aOR 0.95; 0.80-1.12). Odds of any injecting decreased by 38% (aOR 0.62; 0.51-0.75) after HAART initiation. Among the subset of persistent injectors, needle-sharing increased nearly two-fold (aOR 1.99; 1.57-2.52). Behavioral changes were sustained for more than 5 years after HAART initiation and did not differ by consistency of HAART use. Reporting specific high-risk behaviors in the year prior to initiation was a robust predictor of engaging in those behaviors subsequent to HAART. CONCLUSION Overall, substantial declines in sexual risk-taking and active injecting argue against significant behavioral compensation among IDUs following HAART initiation. These data also provide evidence to support identifying persons with risky pre-HAART behavior for targeted behavioral intervention.