Adherence to Antiretroviral Therapy During and After Pregnancy: Cohort Study on Women Receiving Care in Malawi's Option B+ Program

BACKGROUND  Adherence to antiretroviral therapy (ART) is crucial to preventing mother-to-child transmission of HIV and ensuring the long-term effectiveness of ART, yet there is little data from African routine care programmes on maternal adherence to triple ART. METHODS  We analysed data of women who started ART at 13 large health facilities in Malawi between September 2011 and October 2013. We defined adherence as the percentage of days "covered" by pharmacy claims. Adherence of ≥90% was deemed adequate. We calculated inverse probability of censoring weights to adjust adherence estimates for informative censoring. We used descriptive statistics, survival analysis and pooled logistic regression to compare adherence between pregnant and breastfeeding women eligible for ART under Option B+, and non-pregnant and non-breastfeeding women who started ART with low CD4 or with WHO clinical stage 3/4 disease. RESULTS  Adherence was adequate for 73% of the women during pregnancy, for 66% in the first three months postpartum, and for about 75% during months 4-21 postpartum. About 70% of women who started ART during pregnancy and breastfeeding adequately adhered during the first 2 years of ART, but only about 30% of them maintained adequate adherence at every visit. Risk factors for inadequate adherence included starting ART with an Option B+ indication, at a younger age, or at a district hospital or health centre. CONCLUSIONS  One-third of women retained in the Option B+ programme inadequately adhered during pregnancy and breastfeeding, especially soon after delivery. Effective interventions to improve adherence among Option B+ women should be implemented.