Adult patients' adherence to anti-retroviral treatment: a survey correlating pharmacy refill records and pill counts with immunological and virological indices.

Background: Providing anti-retroviral therapy (ART) to patients free of charge enhances their wellbeing, reduces the number of opportunistic infections and enables them to live productive lives, but only if these drugs are taken regularly every day for the rest of their lives. Patients' ART adherence levels are difficult and expensive to estimate. If simple available measures, such as pharmacy refill records, could be correlated with laboratory test results for improved CD4 counts (indicating immunological recovery) and decreased viral loads (VLs--indicating virological recovery), these could be used as preliminary measures of adherence.