Adherence to highly active antiretroviral therapy predicts virologic outcome at an inner-city human immunodeficiency virus clinic

This study's hypothesis is that human immunodeficiency virus-infected patients in the inner city (predominantly injection drug users and ethnic minorities) do not take highly active antiretroviral therapy (HAART) as prescribed and that nonadherence leads to virologic failure. A prospective, observational, 3-month study of adherence to HAART was undertaken at an inner-city clinic. There were 40 subjects [110 subject-months]; 30 were male, 10 were female, 75% were Hispanic, 23% were African American, 68% were injection drug users, and 68% were receiving triple therapy. At 3 months, adherence, which was determined by use of the Medication Event Monitoring System (Aprex) was significantly associated with virologic success: lower virus loads were associated with a rate of adherence of >80% (P<.05). Although nonadherence predicted virologic failure, virologic success was not always predicted by adherence: 11 (27.5%) of 40 subjects with suboptimal adherence rates (<90%) had complete virologic suppression.