Botswana has an adult HIV prevalence of 21.9%. An estimated 317,945 patients (84% of HIV-infected individuals) are on treatment. National guidelines recommend both CD4 count and viral load monitoring. Since the country adopted universal test-and-treat in June 2016, an increasing burden has been placed on the health system. This study aims to assess the ongoing need for regular CD4 monitoring in Botswana.
Data from all HIV-infected patients having CD4 counts at the Gaborone clinics served by the Botswana Harvard reference laboratory during 2015, 2016, and 2017 were analysed. CD4 count and viral load data were assessed to determine the proportion of patients presenting with advanced disease (CD4<200 cells/µL), trends in CD4 cell counts over time, and the proportion of patients presenting without advanced disease experiencing a drop in CD4 count to below 200 cell/µL during follow up.
193,050 CD4 counts were performed on 60,899 patients, with a median frequency of monitoring of 1.48 CD4 measurements per patient per year. 76% (46,474) of patients were established clinic patients, while 24% (14,425) were new to care during the study period. 24.8% (3,571/14,425) of new patients presented with CD4 count<200 cell/µL. Age and sex were strongly associated with advanced disease, with men more likely to present with advanced disease than women (34.9% vs 18.9%, p<0.001). Increased age was associated with lower CD4 cell count. 54% of patients with baseline CD4 cell counts below 200 cell/µL attained a CD4 rise to above 200 cell/µL within 12 months of follow-up. In patients with two or more CD4 counts, a very small proportion (3.6% (180/5060)) of those with a baseline CD4 cell count ≥200 cell/µL experienced a drop in CD4 cell count to <200 cell/µL over the study period. 58.9% (106/180) of patients with a drop in CD4 count had a viral load measurement within 2 months of CD4 measurement, of these, 79.2% (84/106) were virally suppressed.
A significant proportion of patients in Botswana still present with advanced disease, demonstrating the ongoing importance of baseline CD4 testing to identify patients at risk of opportunistic infections and in need of interventions including cotrimoxazole prophylaxis and cryptococcal antigen screening. Very few individuals with CD4 counts above 200 cells/µL experienced a drop to below 200 cells/µL, suggesting limited utility for ongoing CD4 count monitoring in individuals without advanced disease in settings with routine viral load testing.