Adherence to antiretroviral therapy in HIV-positive adolescents in Uganda assessed by multiple methods a prospective cohort study

Abstract

Background: The effectiveness of traditional adherence measurements used in adolescent populations isdifficult to assess. Antiretroviral (ARV) adherence research among adolescents living with HIV in resourceconstrained countries is particularly challenging and little evidence is available. Objectives: The primary objective of this study was to determine the feasibility of a large-scale, long-term study using electronic adherence monitoring in Uganda. The secondary objective was to compare accuracy of pill count (PC) and self-report (SR) adherence with electronic medication vials (eCAPs ). Methods: Adolescents receiving ARV therapy at the Joint Clinical Research Centre in Kampala, Uganda, were recruited. ARVs were dispensed in eCAPs for 1 year. Person-pill-days (PPDs) [1 day where adherence was measured for one medication in one patient] were calculated and a weighted paired t-test was used to compare the levels of adherence among subjects for three different adherence measurement methods. Results: Fifteen patients were included: 40% were female, mean age was 14 years, mean baseline CD4+ cell count was 244 cells/mL, and average treatment duration was 9 months at study entry. Overall, 4721 PPDs were observed. Some eCAPs required replacement during the study resulting in some data loss. Consent rate was high (94%) but was slow due to age limit cut-points. Overall adherence for SR was 99%, PC was 97% and eCAP was 88% (p < 0.05 for all comparisons). 93%, 67% and 23% of patients had an adherence of greater than 95% as measured by SR, PC and eCAP methods, respectively. Conclusions: A large-scale adherence study in Uganda would be feasible using a more robust electronic monitoring system. Adherence measurements produced by PCs and self-reporting methods appear to overestimate adherence measured electronically.