HIV viral load patterns and risk factors among women in prevention of mother-to-child transmission (PMTCT) programs to inform differentiated service delivery (DSD).

BACKGROUND: Differentiated service delivery (DSD) approaches decrease frequency of clinic visits for individuals who are stable on antiretroviral therapy (ART). It is unclear how to optimize DSD models for postpartum women living with HIV (PWLH). We evaluated longitudinal HIV viral load (VL) and cofactors, and modelled DSD eligibility with virologic failure (VF) among PWLH in PMTCT programs.

METHODS: This analysis used programmatic data from participants in the Mobile WAChX trial (NCT02400671). Women were assessed for DSD-eligibility using the WHO criteria among general people living with HIV (receiving ART for ≥6 months and having at least one suppressed VL [<1,000 copies/mL] within the past 6 months). Longitudinal VL patterns were summarized using group-based trajectory modelling (GBTM). VF was defined as having a subsequent VL ≥1,000 copies/mL after being assessed as DSD-eligible. Predictors of VF were determined using log-binomial models among DSD-eligible PWLH.

RESULTS: Among 761 women with 3,359 VL results (median 5 VL per woman), a three-trajectory model optimally summarized longitudinal VL, with most (80.8%) women having sustained low probability of unsuppressed VL. Among women who met DSD criteria at 6 months postpartum, most (83.8%) maintained viral suppression until 24 months. Residence in Western Kenya, depression, reported interpersonal abuse, unintended pregnancy, nevirapine-based ART, low-level viremia (VL 200-1,000 copies/mL), and drug resistance were associated with VF among DSD-eligible PWLH.

CONCLUSIONS: Most postpartum women maintained viral suppression from early postpartum to 24 months and may be suitable for DSD referral. Women with depression, drug resistance and detectable VL need enhanced services.