The changing use and program costs of HIV-related laboratory testing over 20 years in an HIV cohort

The improved health of persons with HIV (PWH) resulting from antiretroviral therapy (ART) has led to recommendations for reduced laboratory monitoring. We studied, for all PWH in care over 20 years at the Southern Alberta Clinic (SAC), Canada, the changing use and results of HIV-specific laboratory testing [i.e., CD4+ testing, plasma HIV viral load (PVL), and genotypic antiretroviral resistance testing (GART)].In this descriptive retrospective longitudinal cohort observational study, we examined HIV-specific laboratory testing for all PWH from 2000 to 2020 within the context of HIV-related health outcomes, program costs, and mortality.

The number of PWH in care increased from 755 in 2000 to 2050 in 2020. Annual CD4+ testing per PWH increased from 2.7 per person in 2000 peaking to 3.5 in 2005 but decreasing to 1.4 by 2020. Annual PVL tests per PWH gradually decreased from 3.2 in 2000 to 2.0 in 2020. GART increased from 93 tests in 2000 to 315 in 2008 decreasing to 127 in 2020. Patients received GART at baseline, and after a viral breakthrough when indicated. Viral suppression rates for the population increased from 66 to 96%; median CD4+ cell count increased from 443 to 470 cells/μl, and overall morbidity decreased from 9.2 to 2.0% by 2020, respectively. Annual per patient laboratory costs decreased from a high of $302 in 2008 to $161 by 2020.

The reduced annual laboratory surveillance per PWH associated with modern ART resulted in modest cost savings and no apparent loss in quality of HIV care.