Programmatic Retention in Prevention of Mother-to-Child Transmission (PMTCT) Programs: Estimated Rates and Cofactors Using Different Nonretention Measures.

Abstract

Prevention of mother-to-child transmission programs serve women continuing and initiating antiretroviral therapy (ART) in pregnancy, and follow-up schedules align to delivery rather than ART initiation, making conventional HIV retention measures (assessed from ART initiation) challenging to apply. We evaluated 3 measures of peripartum nonretention in Kenyan women living with HIV from pregnancy to 2 years postpartum. This longitudinal analysis used programmatic data from the Mobile WAChX trial (NCT02400671). Outcomes included loss to follow-up (LTFU) (no visit for ≥6 months), incomplete visit coverage (<80% of 3-month intervals with a visit), and late visits (>2 weeks after scheduled date). Predictors of nonretention were determined using Cox proportional hazards, log-binomial, and generalized estimating equation models. Among 813 women enrolled at a median of 24 weeks gestation, incidence of LTFU was 13.6/100 person-years; cumulative incidence of LTFU by 6, 12, and 24 months postpartum was 16.7%, 20.9%, and 22.5%, respectively. Overall, 35.5% of women had incomplete visit coverage. Among 794 women with 12,437 scheduled visits, a median of 11.1% of visits per woman were late (interquartile range 4.3%-23.5%). Younger age, unsuppressed viral load, unemployment, ART initiation in pregnancy, and nondisclosure were associated with nonretention by all measures. Partner involvement was associated with better visit coverage and timely attendance. Women who became LTFU had higher frequency of previous late visits (16.7% vs. 7.7%, P < 0.0001). Late visit attendance may be a sentinel indicator of LTFU. Identified cofactors of prevention of mother-to-child transmission programmatic retention may differ depending on retention measure assessed, highlighting the need for standardized measures.