Factors affecting adherence to antiretroviral therapy

In both clinical trials and clinical practice, nonadherence to medications is widespread among patients with chronic diseases. The shift to combinatio n therapies for treating human immunodeficiency virus (HIV)-infected indivi duals has increased adherence challenges for both patients and health-care providers. Estimates of average rates of nonadherence to antiretroviral the rapy range from 50% to 70%, Adherence rates of <80% are associated with det ectable viremia in a majority of patients. The principal factors associated with nonadherence appear to be patient-related, including substance and al cohol abuse. However, other factors may also contribute, such as inconvenie nt dosing frequency, dietary restrictions, pill burden, and side effects; p atient-health-care provider relationships; and the system of care. We discu ss the major reasons reported by HIV-infected individuals for not taking th eir medications. Improving adherence probably requires clarifying the treat ment regimen and tailoring it to patient lifestyles.