Low Non-structured Antiretroviral Therapy Interruptions in HIV-Infected Persons Who Inject Drugs Receiving Multidisciplinary Comprehensive HIV Care at an Outpatient Drug Abuse Treatment Center

Continuous HIV treatment is necessary to ensure successful combined antiretroviral therapy (cART). The aim of this study was to evaluate the incidence of patient-initiated non-structured treatment interruptions in HIV-infected persons who inject drugs and who received a multidisciplinary comprehensive program, including medical HIV care, drug-dependence treatment and psychosocial support, at a drug outpatient addiction center. Non-structured treatment interruptions were defined as ≥30 consecutive days off cART without medical indication. During a median follow-up of 53.8 months, 37/132 (28 %) patients experienced the first non-structured treatment interruptions. The cumulative probability of cART interruption at 5 years was 31.2 % (95 % CI 22.4–40.0). Current drug use injection ≥1/day (HR 14.77; 95 % CI 5.90–36.96) and cART naive patients (HR 0.35, 95 % CI 0.14–0.93) were predictive factors for non-structured treatment interruptions. HIV care provided at a drug addiction center is a useful strategy to sustain continuous cART, however, drug abstinence is essential for the long-term maintenance of cART.