Multiple validated measures of adherence indicate high levels of adherence to generic HIV antiretroviral therapy in a resource-limited setting

Background: There are no validated measures of adherence to HIV antiretroviral therapy in resource-poor settings. Such measures are essential to understand the unique barriers to adherence as access to HIV antiretroviral therapy expands. Methods: We assessed correspondence between multiple measures of adherence and viral load suppression in 34 patients purchasing generic Triomune antiretroviral therapy (coformulated stavudine, lamivudine, and nevirapine; CIPLA, Ltd., Mumbai, India) in Kampala, Uganda. Measures included 3-day patient self-report, 30-day visual analog scale, electronic medication monitoring, and unannounced home pill count. HIV-1 load was determined at baseline and 12 weeks. Results: Mean adherence was 91%-94% by all measures. Seventy-six percent of subjects had a viral load of <400 copies/mL at 12 weeks. All measures were closely correlated with each other (R = 0.77-0.89). Each measure was also significantly associated with 12-week HIV load. There was no significant difference between patient-reported and objective measures of adherence. Conclusions: This sample of patients purchasing generic HIV antiretroviral therapy has among the highest measured adherence reported to date. Patient-reported measures were closely associated with objective measures. The relative ease of administration of the 30-day visual analog scale suggests that this may be the preferred method to assess adherence in resource-poor settings.