# Retrospective cohort analysis of antiretroviral therapy initiation timelines and clinical outcomes in adults with HIV and TB disease in KwaZulu-Natal, South Africa

## TL;DR

This study examines when people with HIV and tuberculosis in South Africa start antiretroviral therapy and how it affects their health outcomes.

## Contribution

The study provides new insights into the impact of ART initiation timing on tuberculosis treatment success and HIV viral suppression in co-infected patients.

## Key findings

- Early ART initiation (within 15 days) was associated with better tuberculosis treatment outcomes.
- Delayed ART initiation (57–210 days) was linked to lower likelihood of HIV viral suppression.
- Only 29.8% of patients initiated ART within the recommended early timeframe.

## Abstract

We aimed to determine antiretroviral therapy (ART) initiation timing and outcomes in people living with HIV (PLHIV) receiving tuberculosis treatment in KwaZulu-Natal, South Africa.

We performed a retrospective cohort analysis of routinely collected de-identified data from 62 clinics including PLHIV not already receiving ART aged ≥16 years, starting tuberculosis treatment between October 2016–November 2019. Multivariable Poisson regression models with robust standard errors evaluated associations between timing of ART initiation (after starting tuberculosis treatment) and successful tuberculosis treatment, and 6-month HIV viral load (VL) < 50 copies/mL.

Among 5,548 PLHIV with tuberculosis, 29.8% initiated ART within 15 days (“early”), 36.2% in 16–56 days, 8.7% in 57–210 days, with 25.3% not initiating ART by 7 months. Proportions with successful tuberculosis treatment were similar comparing 16–56 and 57–210 days to early initiation, with a lower likelihood of successful tuberculosis outcome with no ART within 7 months (adjusted risk ratio [aRR] 0.81 [0.77–0.86], p < 0.001). In those with a known VL 6 months post-ART initiation (n = 2,658), initiation within 57–210 days had a lower likelihood of viral suppression (aRR 0.90 [0.82–0.99], p < 0.03).

Although <30% of PLHIV with tuberculosis initiated ART early, this was associated with better tuberculosis outcomes and VL suppression.