Article Text

Risk factors of mortality among patients hospitalised with COVID-19 in a critical care or hospital care unit: analysis of the French national medicoadministrative database
  1. Eric Ouattara1,
  2. Amelie Bruandet2,
  3. Aurélie Borde1,
  4. Xavier Lenne2,
  5. Florence Binder-Foucard3,
  6. Maggie Le-bourhis-zaimi4,
  7. Joris Muller3,
  8. Pierre Tran ba loc3,
  9. Fabienne Séguret5,
  10. Sophie Tezenas du Montcel6 and
  11. Véronique Gilleron1
  1. 1Medical Information Department, Medical information Analysis and Coordination Unit (UCAIM), University Hospital Centre Bordeaux, Bordeaux, France
  2. 2Medical Information Department, Lille University Hospital Center, Lille, Hauts-de-France, France
  3. 3Public Health Department, University Hospitals Strasbourg, Strasbourg, Alsace, France
  4. 4Medical Information Department, Hospices Civils de Lyon, Lyon, Auvergne-Rhône-Alpes, France
  5. 5Unit of Evaluation and Epidemiologic Studies on National Hospitalization Databases, Department of Epidemiology, Biostatistics and Medical Information, University Hospital Centre Montpellier, Montpellier, Languedoc-Roussillon, France
  6. 6Sorbonne University, INSERM, Pierre Louis Epidemiology and Public Health Institute, Assistance Publique- Hopitaux de Paris, Medical Information Department, Pitié Salpêtrière - Charles Foix University Hospital, Paris, Île-de-France, France
  1. Correspondence to Dr Eric Ouattara; eric.ouattara{at}


Objective To explore mortality risk factors for patients hospitalised with COVID-19 in a critical care unit (CCU) or a hospital care unit (HCU).

Design Retrospective cohort analysis using the French national (Programme de médicalisation des systèmes d’information) database.

Setting Any public or private hospital in France.

Participants 98 366 patients admitted with COVID-19 for more than 1 day during the first semester of 2020 were included. The underlying conditions were retrieved for all contiguous stays.

Main outcome measures In-hospital mortality and associated risk factors were assessed using frailty Cox models.

Results Among the 98 366 patients included, 25 765 (26%) were admitted to a CCU. The median age was 66 (IQR: 55–76) years in CCUs and 74 (IQR: 57–85) years in HCUs. Age was the main risk factor of death in both CCUs and HCUs, with adjusted HRs (aHRs) in CCUs increasing from 1.60 (95% CI 1.35 to 1.88) for 46 to 65 years to 8.17 (95% CI 6.86 to 9.72) for ≥85 years. In HCUs, the aHR associated with age was more than two times higher. The gender was not significantly associated with death, aHR 1.03 (95% CI 0.98 to 1.09, p=0.2693) in CCUs. Most of the underlying chronic conditions were risk factors for death, including malignant neoplasm (CCU: 1.34 (95% CI 1.25 to 1.43); HCU: 1.41 (95% CI 1.35 to 1.47)), cirrhosis without transplant (1.41 (95% CI 1.22 to 1.64); 1.27 (95% CI 1.12 to 1.45)) and dementia (1.30 (95% CI 1.16 to 1.46); 1.07 (95% CI 1.03 to 1.12)).

Conclusion This analysis confirms the role of age as the major risk factor of death in patients with COVID-19 irrespective to admission to critical care and therefore supports the current vaccination policies targeting older individuals.

  • COVID-19
  • respiratory infection
  • viral infection

Data availability statement

Data may be obtained from a third party and are not publicly available.

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Data availability statement

Data may be obtained from a third party and are not publicly available.

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  • Contributors All authors were involved in the conception and design of the study. XL and ABo accessed and verified the underlying data. Data cleaning and analysis were performed by ABo, XL, ABr and EO. The first draft was written by EO. All authors were involved in the interpretation of the results, critically reviewed the manuscript and approved the final version. VG is guarantor and attests that all listed authors meet authorship criteria and that no others meeting the criteria have been omitted.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.