Determinants of HAART discontinuation among injection drug users.

The objective of this study was to identify psychosocial determinants of, and self-reported reasons for, HAART discontinuation among HIV-positive injection drug users (IDUs). We examined correlates between sociodemographic characteristics, drug use and risk behaviors, outcome expectations, adherence self-efficacy, social support and HAART discontinuation among 160 HIV-positive participants in the Vancouver Injection Drug Users' Study (VIDUS). Logistic regression was used to identify the factors independently associated with discontinuation of HAART. Seventy-one (44%) study participants discontinued HAART during the study period. Factors independently associated with discontinuation of HAART included recent incarceration (OR = 4.84, p = 0.022), negative outcome expectations (OR = 1.41, p = 0.001), adherence efficacy expectations (OR = 0.70, p = 0.003) and self-regulatory efficacy (OR = 0.86, p = 0.050). The most frequently cited reasons provided for discontinuing HAART were being in jail (44%) and medication side effects (41%). The results of this study suggest that psychological constructs derived from self-efficacy theory are highly germane to the understanding of HAART discontinuation behavior and interventions that may change it. Incarceration may result in interruptions in HAART among IDUs, and programmatic changes may be needed to promote optimal retention on HAART among incarcerated HIV-infected IDUs.