Since 2015 the World Health Organization has recommended CD4 testing before starting antiretroviral therapy (ART) to detect advanced disease and routine viral load (VL) testing at 6 months and every 12 months thereafter to detect treatment failure. We assessed trends in CD4 and VL testing in six countries in Southern Africa.
We included adults (≥15 years old) who started ART at one of the HIV treatment programs that participate in the International epidemiology Databases to Evaluate AIDS (IeDEA) Southern Africa region between 2005 and 2017, and had ≥8 months of follow-up time from ART start. We assessed the percent of patients with a CD4 count at ART initiation, the percent with a VL test ≥6 months after ART start and, of those, the percent with virologic failure at the first test ≥6 months after ART start. Virologic failure was defined as VL ≥1000 cells/mm3. The CD4 count at ART start was defined as a CD4 count within a window of 3 months before to 1 week after ART start. Analyses were stratified by sex, age and year of ART start.
Our analysis included 520,175 adults from 14 programs in six countries with a median (IQR) age of 34.4 (28.7-41.3) years, of whom 65.0% were female. Median (IQR) follow-up time was 43.6 (23.2-73.0) months and similar across countries. The percent with CD4 testing at ART start has declined over the years from a high of 76.2% in 2005 to a low of 49.4% in 2017. In recent years, the frequency of CD4 testing has also decreased, most notably in Malawi, South Africa and Lesotho (Figure). Women aged 15-24 years had the least CD4 testing (62.5%) and men aged 25-49 years the most (68.3%). Young men aged 15-24 years had the least VL testing (38.4%) and women aged 25-49 years had the most (48.0%). Of those with a VL test, 11.4% had virologic failure with young men aged 15-24 years at greatest risk (19.5%) and women 50+ years at lowest risk (6.2%). Virologic failure has been decreasing in recent years, from 13.7% in 2010 to 8.6% in 2015.
CD4 testing at ART start has steadily declined over the years, alongside reduced CD4 testing in general. Virologic failure has been declining; however, without expanded CD4 and VL testing, many patients with advanced disease or with treatment failure may go undetected.