The benefits of investments to combat HIV, tuberculosis and malaria for primary health care, 2000-23: an economic modeling analysis

Background: Investments to combat HIV, tuberculosis, and malaria (HTM) have delivered substantial health gains in high-burden settings. There is limited evidence on how this has affected primary health care (PHC). We estimated the changes in PHC utilization and associated cost savings resulting from scale-up of HTM interventions in 108 low- and middle-income countries over 2000-2023. Methods: For each disease, we applied validated mathematical models quantifying the incremental differences in PHC outpatient visits and inpatient bed-days by individuals with untreated symptomatic HIV, tuberculosis, or malaria. By country and year, we compared the actual scale-up of HTM services scenario against a counterfactual scenario holding HTM intervention coverage constant at year 2000 levels. We estimated the cost savings associated with these utilization reductions, and compared results to national hospital capacity and health expenditure. Findings: Over 2000-2023, scale-up of HTM services averted an estimated 6.9 (95% interval: 4.4-10.4) billion PHC outpatient visits and 3.9 (2.5-6.1) billion inpatient bed-days, equivalent to US$135 (77-225) billions in total cost savings. Reductions in utilization and cost savings were greatest in the Sub-Saharan Africa and East Asia and Pacific regions. For 2023, a median of 4.4% of hospital bed capacity and 1.6% of government health expenditures were freed-up across study countries. These percentages were 22.9% and 5.1% respectively for low-income countries. Interpretation: Sustained investments in HTM services in high-burden settings generated substantial cost savings over recent decades through reduced PHC utilization. These benefits should be considered when assessing investment impact. Funding: The Global Fund.