The economic cost of outpatient primary care of adults with multimorbidity (HIV, diabetes, and hypertension) in rural South Africa.

Sub-Saharan Africa (SSA) is experiencing an epidemiological transition where non-communicable diseases are becoming the leading cause of disability and mortality alongside infectious diseases such as HIV/AIDS. Multimorbidity, the coexistence of two or more long-term conditions, is increasing in SSA. However, the cost of managing multimorbidity is largely unknown. This study aimed to estimate the economic cost of public outpatient primary care for adults with multimorbidity (HIV, hypertension, and/or diabetes, and their associated conditions: cardiovascular disease, and TB) in rural South Africa. This study used a cross-sectional, retrospective cost-of-illness approach to estimate the direct and indirect costs of multimorbidity management in Bushbuckridge, Mpumalanga, in 2022. Data were synthesized from patient-level data from eight public primary healthcare facilities within the Agincourt study site-a rapidly transitioning rural South African setting. Additionally, government reports and an existing study on transport costs and productivity losses conducted within the Agincourt study site were used to estimate the costs of managing patients in the primary care facilities. Results showed that patients with multimorbidity had higher average economic costs per patient compared to those with single conditions. Overall, patients with multimorbidity increase costs above the baseline of a patient with a single condition (R4 900/annum) by between 42% and 83%. Patients with multimorbidity also incur slightly higher costs associated with accessing primary care services compared to those with a single condition. However, our model shows that the additive cost of managing multiple conditions in separate consultations is higher than managing all conditions in one visit. This shows that managing patients within an integrated care model seems to have a cost-limiting effect. However, treatment guidelines for managing multimorbidity in South Africa should be developed to ensure standardized care.