Trends in CD4 and viral load testing 2005 to 2018: multi‐cohort study of people living with HIV in Southern Africa

Abstract

Introduction The World Health Organization (WHO) recommends a CD4 cell count before starting antiretroviral therapy (ART) to detect advanced HIV disease, and routine viral load (VL) testing following ART initiation to detect treatment failure. Donor support for CD4 testing has declined to prioritize access to VL monitoring. We examined trends in CD4 and VL testing among adults (≥15 years of age) starting ART in Southern Africa. Methods We analysed data from 14 HIV treatment programmes in Lesotho, Malawi, Mozambique, South Africa, Zambia and Zimbabwe in 2005 to 2018. We examined the frequency of CD4 and VL testing, the percentage of adults with CD4 or VL tests, and among those having a test, the percentage starting ART with advanced HIV disease (CD4 count <200 cells/mm 3 ) or failing to suppress viral replication (>1000 HIV‐RNA copies/mL) after ART initiation. We used mixed effect logistic regression to assess time trends adjusted for age and sex. Results Among 502,456 adults, the percentage with CD4 testing at ART initiation decreased from a high of 78.1% in 2008 to a low of 38.0% in 2017; the probability declined by 14% each year (odds ratio (OR) 0.86; 95% CI 0.86 to 0.86). Frequency of CD4 testing also declined. The percentage starting ART with advanced HIV disease declined from 83.3% in 2005 to 23.5% in 2018; each year the probability declined by 20% (OR 0.80; 95% CI 0.80 to 0.81). VL testing after starting ART varied; 61.0% of adults in South Africa and 10.7% in Malawi were tested, but fewer than 2% were tested in the other four countries. The probability of VL testing after ART start increased only modestly each year (OR 1.06; 95% CI 1.05 to 1.06). The percentage with unsuppressed VL was 8.6%. There was no evidence of a decrease in unsuppressed VL over time (OR 1.00; 95% CI 0.99 to 1.01). Conclusions CD4 cell counting declined over time, including testing at the start of ART, despite the fact that many patients still initiated ART with advanced HIV disease. Without CD4 testing and expanded VL testing many patients with advanced HIV disease and treatment failure may go undetected, threatening the effectiveness of ART in sub‐Saharan Africa.

Regression discontinuity analysis demonstrated varied effect of Treat-All on CD4 testing among Southern African countries

“…We found more than 75% of PLHIV in South Africa had viral load monitoring just after policy adoption, whereas coverage was less than 13% elsewhere. These findings are consistent with several recent studies, which reported disparities in viral load monitoring among income groups and countries in Southern Africa [10][11][12].…”

“…Despite the importance of CD4 and viral load testing, recent studies show declining pre-ART CD4 testing with HIV treatment expansion in several Southern African countries and no increases in viral load testing [10,11]. Additionally, a global study found that Treat-All adoption led to decreased pre-ART CD4 testing in low and lower-middle income countries while remaining high in upper-middle and high income countries [12].…”

Effects of National Adoption of Treat-All Guidelines on Pre-Antiretroviral Therapy (ART) CD4 Testing and Viral Load Monitoring After ART initiation: A Regression Discontinuity Analysis

“…Despite its importance for guiding HIV care, since adoption of Treat-All, pre-ART CD4 testing is increasingly deprioritized in favor of scaling up viral load (VL) testing for patients on ART [ 4 , 9 , 10 ]. The US President’s Emergency Fund for AIDS Relief (PEPFAR) has reduced support for pre-ART CD4 testing—even in settings where capacity for VL testing remains suboptimal [ 3 , 5 , 10 , 11 ]—and studies suggest that pre-ART CD4 testing has decreased markedly in recent years [ 12 , 13 ], raising concerns about potential negative consequences for patient care. While VL monitoring is recommended at 6 and 12 months after ART initiation and at least annually thereafter to ascertain treatment success or failure and to guide decisions regarding regimen switches and differentiated care strategies [ 14–17 ], it is not a substitute for pre-ART CD4 testing, and it has limited value for assessing disease progression and mortality risks for patients entering or re-engaging in care [ 18 ].…”

HIV transmission in sero-discordant couples with the HIV-positive partner in Xinjiang: incidence and associated predictors

“…In this study, by LASSO Cox model, we found that with the increase of CD4 + T lymphocyte count, the risk of HIV seroconversion in the negative partner decreased gradually. CD4 + T cells count decline over time and are the best predictor of disease progression and risk of death, especially in patients with advanced HIV [42]. CD4 + T cells counts are used to guide some preventive and diagnostic interventions, including prioritizing detection of opportunistic infections [43].…”