To compare electronically monitored (MEMS) with self-reported adherence in drug users, including the impact of adherence on HIV load, we conducted a 6-month observational study of 67 antiretroviral-experienced current and former drug users. Adherence (percentage of doses taken as prescribed) was calculated for both the day and the week preceding each of 6 research visits. Mean self-reported 1-day adherence was 79% (median, 86%), and mean self-reported 1-week adherence was 78% (median, 85%). Mean MEMS 1-day adherence was 57% (median, 52%), and mean MEMS 1-week adherence was 53% (median, 49%). One-day and 1-week estimates were highly correlated (r>.8 for both measures). Both self-reported and MEMS adherence were correlated with concurrent HIV load (r=.43-.60), but the likelihood of achieving virologic suppression was greater if MEMS adherence was high than if self-reported adherence was high. We conclude that self-reported adherence is higher than MEMS adherence, but a strong relationship exists between both measures and virus load. However, electronic monitoring is more sensitive than self-report for the detection of nonadherence and should be used in adherence intervention studies.

Moderate alcohol consumption is associated with a decreased incidence of diabetes mellitus and a decreased incidence of heart disease in persons with diabetes. Further studies are needed to assess the long-term effects of alcohol consumption on glycemic control and noncardiac complications in persons with diabetes.

Accurate measurement of antiretroviral adherence is essential for targeting and rigorously evaluating interventions to improve adherence and prevent viral resistance. Across diseases, medication adherence is an individual, complex, and dynamic human behavior that presents unique measurement challenges. Measurement of medication adherence is further complicated by the diversity of available measures, which have different utility in clinical and research settings. Limited understanding of how to optimize existing adherence measures has hindered progress in adherence research in both HIV and other diseases. Though self-report is the most widely used adherence measure and the most promising for use in clinical care and resource limited settings, adherence researchers have yet to develop evidence-based standards for self-reported adherence. In addition, the use of objective measures, such as electronic drug monitoring or pill counts, is limited by poor understanding of the source and magnitude of error biasing these measures. To address these limitations, research is needed to evaluate methods of combining information from different measures. The goals of this review are to describe the state of the science of adherence measurement, to discuss the advantages and disadvantages of common adherence measurement methods, and to recommend directions for improving antiretroviral adherence measurement in research and clinical care.