Patients' description and resource use in COVID-19 hospitalized patients based on a French claims real-world database

CONTEXT: Coronavirus disease (Covid-19) is an infectious disease caused by the SARS-CoV-2 virus. The disease can cause symptoms ranging from mild to very severe. People with risk factors as age, gender, medical conditions may be more likely to need hospitalization or intensive care if they have Covid-19, or to die of the infection. A retrospective study based on a national French hospitalized claims database (PMSI) over the year 2020 has been performed to support Covid-19 patient's description but also to describe the disease management with a dedicated focus on ventilation status and finally to describe the health care resource use and the economic impact for treatment of Covid-19 in outpatient patients with more than one risk-factor for severe Covid-19. – OBJECTIVES: The main objective was to describe patient's characteristics hospitalized for Covid-19. The secondary objectives were to describe the disease management of Covid-19 according to the ventilation status, the health care resource use for and economic impact of Covid-19 disease management in hospital. METHOD: This retrospective observational study identified people with Covid-19 in the PMSI through hospitalisation diagnosis codes in 2020. 4 ventilation status were identified: without and with oxygen support (O2), with non-invasive ventilation (NIV), with mechanical ventilation (MV) based on CCAM acts. Due to underreporting of medical procedure related to oxygen support, status “without oxygen support” was combined to O2 status. In case of several status in the same stay, the most severe was kept. Risk factors were identified through ICD10 codes, DRG and age. Rehospitalizations were calculated for 1st wave stays (from January to June). A minimum delay of 14 days between 2 stays was applied (to not consider transfer as a rehospitalisation). Cost estimation was performed based on health insurance perspective. RESULTS: About 200,00 patients for 240,00 stays. 1% of stay were in NIV status, 8% in MV. Median age was 69 years and 54% of patients were men. Men were overrepresented in NIV and MV. 10% of people over 80 had MV. 34% of patients had no risk factor (11% of MV patients, 6% of NIV and 36% of O2). The length of stay increases with the requirement of ventilation support. From a mean of 7 days for O2 to 22 days for MV. 16% of patients died (14% of O2, 25% of NIV, 36% of MV). The mortality rate increase with the age, between 1 and 5% for patients younger than 60 years, 9% for 61-65 years, 13% for 66-70 years, 17% for 71-75, 23% for 76-80 years and 33% for patients older than 80 years old. 14% of 1st wave patients were rehospitalised in 2020. The mean cost of Covid-19 hospitalisation was €5,510 (€+/- 7,142) and the median is €3,800. The mean cost of hospitalisation increased with ventilation support intensity from €3,990 (€+/- 3,021) for O2, up to €10, 600 (€+/- 5,534) for NIV and €21,100 (€+/- 15,343) for MV. CONCLUSION: Age, sex and risk factor increased the severity of ventilation support, cost and mortality rates. Elderly people had less MV support, shorter length of stay and lower cost. In this study, requirement for low-flow oxygen support was largely under-reported, due to many reasons: lack of impact of O2 support on stay valorisation, not specified in the registry, and overload of work leading to enter only the most valuable information in the database. This under-reporting could also apply, to a much lesser extent to non-invasive ventilation, as such procedure is associated with increased stay cost. CONFLICT OF INTEREST: VM, KB and KLL are employees of Roche. CL, CB, ALM and AM are employees of Creativ-Ceutical, a contract research organisation under contract with Roche for the implementation and exploitation of this study. FINANCIAL SUPPORT: This study was funded by Roche.