Use of Highly Active Antiretroviral Therapy is Increasing in HIV Positive Severe Drug Users

Background: Substance abuse greatly impacts the effectiveness of highly active antiretroviral therapy (HAART). We analyzed antiretroviral use in drug users positive for human immunodeficiency virus (HIV) that sought substance abuse treatment. Methods: This cross-sectional study recruited 705 patients HIV positive (74.6% men) between 1997 and 2007. Patients were grouped by calendar periods when different HAART regimens were available in Spain (p1: 1997-1999, n=299; p2: 2000-2003, n=249; and p3: 2004-2007, n=157). Results: The mean age at admission was 34 years; 94.7% had a past history of injection drug use (IDU) and 67.7% were current IDUs. The average CD4 cell count was 399 cells/μL [interquartile range: 203-632 cells/μL]. Lifetime prevalence of antiretroviral use was 59.4% (416/705; p1: 48.1%; p2: 64.6%; p3: 72.6%; p<0.05). The overall prevalence of antiretroviral use at admission was 40.7% (p1: 31.4%; p2: 41.0%; p3: 58.0%; p<0.05). In multivariate logistic regression analysis, age, calendar period, and non-IDU were predictors of antiretroviral use at admission. Among those taking antiretrovirals, 21.6% were on suboptimal HAART, mostly in the p1 group. Overall, 44.6% of patients were taking protease inhibitor and non-nucleoside reverse transcriptase inhibitor (PI-NNRTI), 21.9% were taking NRTI-NNRTI, and 9.4% were taking three NRTIs. Although not significant, the three-NRTI regimen was associated with CD4 >350 cells/μL and HIV RNA <400 copies/mL. Conclusions: HAART use is steadily increasing in HIV positive heavy drug users. However, part of this population remains antiretroviral therapy-naive despite advanced immunodeficiency. Interventions that focus on integrating substance abuse with HIV/AIDS treatments are needed.