Validation of a self-report adherence measurement tool among a multinational cohort of children living with HIV in Kenya, South Africa and Thailand.

Abstract

IntroductionThere are few data on adherence and low‐cost measurement tools for children living with HIV. We collected prospective data on adherence to antiretroviral therapy (ART) among a multinational cohort of children to evaluate an adherence questionnaire.MethodsWe enrolled 319 children ages 0 to 16 years on ART in Kenya (n = 110), South Africa (n = 109) or Thailand (n = 100). Children were followed up for six months of adherence monitoring between March 2015 and August 2016 using Medication Event Monitoring Systems (MEMS ®) with at least one viral load measure. At month 3 and 6, children or their caregivers were administered a 10‐item adherence questionnaire. Repeated measures analyses were used to compare responses on questionnaire items to external adherence criteria: MEMS ® dichotomized adherence (≥90% of doses taken vs. <90%), 48‐hour MEMS ® treatment interruptions and viral suppression (<1000 copies/mL). Items associated with outcomes (p < 0.10) were coefficient‐weighted to calculate a total adherence score, which was tested in multivariate regression against MEMS ® and viral suppression outcomes. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated.ResultsMean child age was 11 years and 54% were female. Children from Thailand (median age 14 years) were significantly older compared to Kenya (10 years) and South Africa (10 years). Prevalence of viral suppression was 97% in Thailand, 81% in South Africa and 69% in Kenya, while the prevalence of MEMS ® adherence ≥90% was 57% in Thailand, 58% in South Africa and 40% in Kenya. Across sites, child‐reported adherence using the questionnaire was significantly associated with dichotomized MEMS ® adherence (OR 1.8, 95% CI 1.4 to 2.4), 48‐hour treatment interruptions (OR 0.41, 95% CI 0.3 to 0.6), and viral suppression (OR 3.4, 95% CI 1.7 to 6.7). We did find, however, that different cut‐points for the adherence score may be context‐specific. For example, MEMS ® non‐adherent children in Kenya had a lower adherence score (0.98) compared to South Africa (1.77) or Thailand (1.58).ConclusionsWe found suboptimal adherence to ART was common by multiple measures in this multi‐country cohort of children. The short‐form questionnaire demonstrated reasonable validity to screen for non‐adherence in these diverse settings.