Changes in access to viral load testing, incidence rates of viral load suppression and rebound following the introduction of the 'universal test and treat' guidelines in Cameroon: A retrospective follow-up analysis

Abstract

Cameroon adopted and started implementing in 2016, the 'universal test and treat' (UTT) guidelines to fast-track progress towards the 95-95-95 ambitious targets to end the HIV epidemic. Achieving the third 95 (viral load suppression) is the most desirable target in HIV care. We aimed to evaluate the effectiveness of this novel approach on access to viral load testing (VLT), viral suppression (VLS), and viral load rebound (VLR). A retrospective cohort study was conducted at The Nkongsamba Regional Hospital to compare VLT outcomes between the pre-UTT (2002 to 2015) and the post-UTT (2016 to 2020) periods. We used a data extraction form to collect routine data on adult patients living with HIV. We measured uptake levels of the first and serial VLT and compared the incidence rates of VLS (VL<1000 copies/ml) and viral load rebound (VLR) before and after introducing the UTT approach using Kaplan Meier plots and log-rank tests. Cox regression was used to screen for factors independently associated with VLS and VLR events between the guideline periods. Access to initial VLT increased significantly from 6.11% to 25.56% at 6 months and from 12.00% to 73.75% at 12 months before and after introducing the UTT guidelines respectively. After a total observation time at risk of 17001.63 person-months, the UTT group achieved an incidence rate of 90.36 VLS per 1000 person-months, four-fold higher than the 21.71 VLS per 1000 person-months observed in the pre-UTT group (p<0.0001). After adjusting for confounding, the VLS rate was about 6-fold higher in the UTT group than in the pre-UTT group (adjusted Hazard Rate (aHR) = 5.81 (95% confidence interval (95%CI): 4.43-7.60). The incidence of VLR increased from 12.60 (95%CI: 9.50-16.72) to 19.11 (95%CI: 14.22-25.67) per 1000 person-months before and after the introduction of UTT guidelines respectively. After adjusting, VLR was more than twice as high in the UTT group than in the pre-UTT group (aHR = 2.32, 95%CI: 1.30-4.13). Increased access to initial VLT and higher rates of VLS have been observed but there are concerns that the suppressed viral load may not be durable since the introduction of the UTT policy in this setting.

Fig 1. Study cohort flow chart.

Fig 2. Cumulative access to initial viral load (A and B) and time to repeat viral (C and D) measurements across ART initiation guidelines.

Fig 3. Cumulative rates of viral load suppression across ART initiation periods and strategies.

Fig 4. Retention on low viral load across ART initiation guidelines and periods.