Optimizing HIV virologic outcomes for pregnant and breastfeeding women and infant testing coverage in South Western Uganda

Abstract

Background: Achieving viral suppression among pregnant and breastfeeding women is critical for eliminating vertical transmission of HIV in Sub-Saharan Africa. Adherence to antiretroviral therapy (ART) and disclosure of HIV status are key determinants of viral suppression and play a crucial role in preventing perinatal HIV transmission. However, multiple barriers—including stigma, limited knowledge, and restricted healthcare access—impede these efforts. Peer-led counseling interventions offer a promising approach to improving maternal ART adherence, promoting HIV status disclosure, and enhancing early infant diagnosis by equipping mothers with the knowledge and skills necessary to prevent perinatal HIV transmission. Understanding maternal perceptions of viral suppression is essential for implementing effective strategies to eliminate Vertical transmission of HIV. Objective: To evaluate the effect of the Enhanced Viral Load Counseling and Standardized Peer-Mother Support (ENHANCED-SPS) intervention on viral suppression among pregnant and breastfeeding women living with HIV in rural Uganda, and assess whether peer-led support enhances completion of infant HIV testing. Methods: This was an Implementation Science Research study that utilized a before-and-after cluster randomized trial design conducted in two phases. In phase one, we determined the prevalence of viral suppression and identified motivators and barriers to viral suppression among pregnant and postpartum women using retrospective data from the SEARCH trial. Additionally, we examined facility- and community-level barriers and facilitators of viral suppression among women of reproductive age in southwestern Uganda. Based on these findings, we employed the PRECEDE model of health promotion to design the ENHANCED-SPS intervention, which included enhanced viral load counseling and standardized peer-mother support to address structural barriers and specific needs of the target population. In phase two, we evaluated the ENHANCED-SPS intervention’s impact on viral suppression (primary outcome) and secondary outcomes, including ART adherence, HIV status disclosure, and infant HIV testing. A cluster-randomized trial (NCT04122144) was conducted from September 2019 to October 2021 in 14 high-HIV-prevalence public facilities in rural southwestern Uganda, randomized 1:1 to intervention or standard care. Guided by the PRECEDE model, the intervention included: (1) provider training on viral load counseling (predisposing), (2) standardized peer-mother support with bi-weekly phone counseling (enabling), and (3) point-of-care viral load monitoring with provider-peer feedback (reinforcing). Participants received adherence assessments and tailored plans to address ART and infant testing barriers. Outcomes were analyzed using TMLE to account for missing data, repeated measures, and clustering. Secondary outcomes included ART adherence (≤1 missed dose/month), HIV disclosure, and infant HIV testing (via medical record review). A qualitative sub-study explored women's perceptions of viral suppression using transcribed, coded interviews in Dedoose. Results: In phase one of the study, among enumerated participants at baseline, HIV testing among 15–45-year-old women was high at 92% and 93% with similar HIV prevalence of 12.6% and 12.3%, in intervention and control communities, retrospectively. Among women living with HIV, with a history of pregnancy/live birth, viral suppression was 42% and 44% at baseline, and 81% and 76% (p=0.002) at year 3, respectively. Overall, by year 3, the intervention communities achieved significantly higher viral suppression (77%) compared to controls (68%, p<0.001) among all 15-45-year-old women living with HIV. Pregnancy/live birth was a predictor of year-3 VS in control (p=0.016) but not intervention (p=0.43). Younger age was a risk factor for non-suppression in both arms. In Phase two of the study, a total of 505 pregnant and postpartum women were enrolled between September 2019 and October 2020. The median age was 28 years; 96% were pregnant, 69% had been previously diagnosed with HIV, and 70.0% (95% CI: 65.9–74.1%) were virally suppressed at baseline. After 12 months, viral suppression increased to 94.9% (95% CI: 92.5–97.4%), representing an absolute increase of 24.9% (95% CI: 21.6–28.2%; p < 0.001). The intervention yielded significant improvements in viral suppression across all age groups, among both pregnant and postpartum women, and within strata defined by care status and duration of ART use. Despite a 58.9% (95%CI: 27.4-90.3%) improvement from baseline, viral suppression among post-partum women at 12 months was only 75.7%. ART adherence improved from 68% (95% CI: 62–74%) at baseline to 93% (95% CI: 81–100%) at 12 months, a 25% increase (95% CI: 9–40%; p = 0.009), with the largest gains seen in participants aged 15–24 years, those breastfeeding, or those not virally suppressed at enrollment. HIV status disclosure increased from 80% (95% CI: 69–90%) at baseline to 94% (95% CI: 89–99%) after 12 months, a 14% improvement (95% CI: 8–21%; p = 0.003); similar trends were observed for disclosure to a spouse or partner. Among 464 children (234 in the intervention and 230 in the control arm) born to study participants, final HIV testing (antibody rapid test at 18 months) was completed in 94.5% (95% CI: 91.6–97.5%) of cases in the intervention group versus 83.3% (95% CI: 78.4–88.3%) in the control group, yielding an 11.2% difference (95% CI: 5.4–17.0%; p < 0.001). While there were no significant differences in the proportions completing the 1st (4–6 weeks) or 2nd (9 months) tests, the 3rd test (6 weeks post-breastfeeding cessation) was completed at a rate 14.8% (95% CI: 7.9–21.8%; p < 0.001) higher in the intervention arm. In a qualitative sub-study, women living with HIV described viral suppression in the context of achieving good health and ensuring HIV-free infants. They emphasized that adherence to ART was key to attaining viral suppression and noted that engagement with healthcare providers was crucial, despite experiencing barriers such as anticipated stigma, challenges with HIV status disclosure, pregnancy-related distress, and long distances to health facilities. Conclusion: The multi-component, peer-led ENHANCED-SPS intervention significantly improved viral suppression, ART adherence, and HIV status disclosure among pregnant and postpartum women. The intervention also increased infant HIV testing completion rates, facilitating early diagnosis and timely linkage to care. Despite these successes, viral suppression among breastfeeding women remained suboptimal (75.7%), underscoring the need for additional postpartum interventions. The findings emphasize the importance of culturally sensitive viral suppression education, adherence support, and non-judgmental healthcare environments to enhance maternal and infant health outcomes in HIV care programs.