Hospitalization costs of patients with severe acute respiratory infections due to COVID-19 in a public teaching hospital: a micro-costing approach

OBJECTIVE: To estimate the costs associated with the hospitalization of patients with Severe Acute Respiratory Infection (SARI) due to SARS-CoV-2 in a university hospital affiliated with the Brazilian Unified Health System (SUS) in 2020 and 2021. METHODS: A bottom-up micro-costing approach was used to conduct a cost analysis based on data from a hospital clinical cohort. Patients with confirmed diagnoses of COVID-19 and SARI, admitted to general wards or intensive care units (with or without mechanical ventilation), were included. Healthcare activities were categorized as hospitalization, ventilation, hemodialysis, nutrition, medications, and laboratory tests. Costs were calculated based on individualized consumption of supplies and procedures, also considering the annualized cost of equipment. Comparisons were made between micro-costing and macro-costing (based on the Hospital Admission Authorizations - AIH). RESULTS: A total of 627 patients were analyzed. The total cost was R$ 5,824,366.73 (Int$ 2,307,593.80) when healthcare professionals were excluded and R$19,437,731.25 (Int$ 7,701,161.35) when they were included. Medications accounted for the largest share (52.79%). Micro-costing was 1.7-times higher than macro-costing for hospital costs alone and 2.3-times higher when professional costs were included. Multivariate analysis identified length of hospital stay as the main factor associated with increased costs, while age, sex, and referral origin showed no significant association. CONCLUSION: This study reveals the substantial economic impact of COVID-19-related hospitalizations in high-complexity care settings. It also highlights the importance of improving financing models for the SUS, particularly given the discrepancies between actual costs and federal reimbursement values. These findings contribute to the development of public policies and response strategies for future health emergencies.