Single- versus multiple-tablet HIV regimens: adherence and hospitalization risks.

Objectives: To evaluate the impact of antiretroviral therapy as a single-tablet regimen (STR) and multiple-tablet regimen (MTR) on outcomes in human immunodeficiency virus (HIV)/AIDS patients using electronic health records from the Veterans Healthcare Administration (VHA).

Study Design: Retrospective cohort.

Methods: This study evaluated VHA patients to whom HIV medications were dispensed as STRs or MTRs during the study period (January 1, 2006, to July 30, 2012). Patients were followed from the index date (ie, start of regimen) until treatment discontinuation, end of study period, last date of healthcare-related activity, or death. Differences in outcomes of hospitalization, adherence defined as a medication possession ratio of ≥ 95%, and undetectable viral load were evaluated using a Cox-proportional hazard and logistic model controlling for covariates measured during a 6-month baseline period.

Results: A total of 15,602 patients (6191 STR and 9411 MTR) met all study criteria. The study sample was, on average, aged 52 years with similar CD4 counts (mean ± SD: 432.2 ± 282.8 vs 419.3 ± 280.9; P = .287), but a significantly lower proportion of STR versus MTR patients had an undetectable viral load at baseline (42% vs 46%; P < .001). After controlling for baseline covariates, the STR cohort had twice the odds of being adherent (odds ratio [OR], 1.98; P < .001), 31% had a significantly lower hazard of having a hospitalization (hazard ratio, 0.69; P < .001), and 21% had higher odds of having an undetectable viral load during follow-up (OR, 1.21; P < .001).

Conclusions: STR is associated with higher adherence rates, decreased hospitalizations, and more patients with an undetectable viral load in VHA patients with HIV/AIDS.