Trends and Predictors of Virologic Failure Following Suppression on Antiretroviral Therapy among HIV Infected Children in Kenya

Abstract

Background: There are limited data on the incidence and predictors of virologic failure among HIV infected children on antiretroviral treatment (ART), particularly among children who have previously suppressed virus. We examined incidence, timing, and correlates of virologic failure following suppression in a longitudinal cohort of children on ART. Methods: This analysis utilized data from a prospective cohort study among children 15 months to 12 years old, with moderate to severe HIV disease who were initiated on ART and followed for up to 5.5 years with 3-monthly measurement of plasma HIV RNA levels. Virologic failure was defined as presence of detectable HIV RNA in plasma after achieving viral suppression (<500 copies/ml). A time to event analysis of virologic failure from viral suppression was conducted and predictors of time to virologic failure were determined using Cox proportional hazards regression models. Results: Overall, 149 children were initiated on ART with a median time of follow-up time of 49 months (IQR 35, 60 months). Ninety-four (63.1%) children achieved plasma viral suppression, among whom 32 (34.4%) experienced virologic rebound after suppression with an incidence rate of 13.8 failures/100 person-years. Children whose caregivers were housewives or unemployed were significantly less likely to fail following suppression (HR: 0.34, 95%CI: 0.16, 0.72; P=0.005). Caregivers who did not know if their spouses had been HIV tested were more likely to fail on treatment [HR: 2.48, 95%CI: 1.02, 5.99 P=0.04). There was a trend towards failure among children who were visibly wasted at baseline and those who were initiated on a stavudine- based regimen [HR: 1.86; 95%CI: 0.93, 3.73; P=0.08] and [HR: 1.97, 95%CI: 0.96, 4.04 P=0.06] respectively. Conclusion: We found high rates of virologic failure among HIV infected children on ART despite initial suppression. Caregivers play a critical role in ensuring children’s success on ART and may need programmatic strategies to support their roles. Recognition of children at risk for failure can complement scale up of virologic testing capacity to ensure better outcomes.