Adherence among rural HIV-infected patients in the deep south: a comparison between single-tablet and multi-tablet once-daily regimens.

Background: Once-daily (QD), combination antiretroviral therapy (ART) can impact the willingness and ability of patients to take medications as directed. The impact of antiretroviral (ARV) drug adherence influenced by single-tablet (STR) versus multi-tablet regimens (MTR) among patients enrolled in the AIDS Drug Assistance Program (ADAP) in a rural environment has not yet been assessed.

Material And Methods: A retrospective chart review evaluated adherence and outcomes in adult HIV-infected patients enrolled in the ADAP at 2 ambulatory clinics in the Southeast, taking either a QD STR (efavirenz [EFV]/emtricitabine/tenofovir [TDF]) or a QD protease inhibitor (PI)-based, MTR (atazanavir [ATV], ritonavir [RTV], and emtricitabine/TDF) by evaluating pharmacy refill records, patient self-reported adherence, and virologic response.

Results: A total of 389 patient records were analyzed (STR, n = 165 versus MTR, n = 224). There were more males, a higher percentage of treatment-naive patients, and more patients with a baseline CD4 count of >200 cells/mm(3) in the MTR group. Based on refill records, more patients on MTR were >90% adherent (61.6% versus 51.5%, P = .047). In a multivariable analysis, being treatment experienced was a negative predictor (odds ratio [OR] = 0.48, 0.29-0.78) for adherence. Regimen choice was not associated with adherence. More patients taking MTR were virologically suppressed at the end of the observation period. Regardless of the regimen, being >90% adherent was a significant predictor of virologic suppression (OR = 3.51, 1.98-6.23).

Conclusion: Treatment-experienced patients enrolled in ADAP are less likely to be adherent. A QD PI-based MTR may result in comparable adherence to an STR in a rural HIV-infected population.