Retention on ART and viral suppression among patients in alternative models of differentiated HIV service delivery in KwaZulu-Natal, South Africa

Abstract

Differentiated models of HIV care (DMOC) aim to improve health care efficiency. We describe outcomes of five DMOC in KwaZulu-Natal, South Africa: facility adherence clubs (facility AC) and community adherence clubs (community AC), community antiretroviral treatment (ART) groups (CAG), spaced fast lane appointments (SFLA), and community pick up points (PuP). This retrospective cohort study included 8241 eligible patients enrolled into DMOC between 1/1/2012 and 31/12/2018. We assessed retention in DMOC and on ART, and viral load suppression (<1000 copies/mL). Kaplan-Meier techniques were applied to describe crude retention. Mixed effects parametric survival models with Weibull distribution and clustering on health center and individual levels were used to assess predictors for ART and DMOC attrition, and VL rebound (≥1000 copies/mL). Overall DMOC retention was 85%, 80%, and 76% at 12, 24 and 36 months. ART retention at 12, 24 and 36 months was 96%, 93%, 90%. Overall incidence rate of VL rebound was 1.9 episodes per 100 person-years. VL rebound rate was 4.9 episodes per 100 person-years among those enrolled in 2012-2015, and 0.8 episodes per 100 person-years among those enrolled in 2016-2018 (RR 0.12; 95% CI, 0.09-0.15, p<0.001). Prevalence of confirmed virological failure was 0.6% (38/6113). Predictors of attrition from DMOC and from ART were male gender, younger age, shorter duration on ART before enrollment. Low level viremia (>200-399 copies/mL) was associated with higher hazards of VL rebound and attrition from ART. Concurrent implementation of several DMOC in a large ART program is feasible and can achieve sustained retention on ART and VL suppression.

Fig 1. Annual enrollment of new patients into DMOC, by type of model, 2012–2018, KwaZulu-Natal, South Africa.

Stacked bar char, x-axis = year: the white sub-bar = facility AC, facility adherence club; the green sub-bar = community AC, community adherence club; hatched sub-bar = CAG, community ART group; the black sub-bar = SFLA, spaced and fast lane appointment; the grey sub-bar = PuP, decentralized medication delivery at community pick up points.

Fig 2. Kaplan Meier curves for retention in DMOC, by type of model, KwaZulu-Natal, South Africa.

The long dash black line = facility AC, facility adherence club; the short dash blue line = community AC, community adherence club; the long dash-dot blue line = CAG, community ART group; the solid black line = SFLA, spaced and fast lane appointment model; the dash-dot black line, PuP = decentralized medication delivery at community pick up points.

Fig 3. Kaplan Meier survival curves for probability of retention on ART among patients in DMOC, 2012–2018, KwaZulu Natal, South Africa.

The long dash black line = facility AC, facility adherence club; the short dash blue line = community AC, community adherence club; the long dash-dot blue line = CAG, community ART group; the solid black line = SFLA, spaced and fast lane appointment model; the dash-dot black line, PuP = decentralized medication delivery at community pick up points.