Mortality 30 and 90 days after hospitalisation for COVID-19: prognostic factors on admission to hospital


  • Stephen A. Murphy Department of Respiratory Medicine, University Hospital of North Durham, Durham, United Kingdom
  • Fatimah Khalil Department of Respiratory Medicine, University Hospital of North Durham, Durham, United Kingdom
  • Mohammad Fayaz Department of Respiratory Medicine, University Hospital of North Durham, Durham, United Kingdom
  • Louise Robinson Department of Respiratory Medicine, University Hospital of North Durham, Durham, United Kingdom
  • Natalie M. Cummings Department of Respiratory Medicine, University Hospital of North Durham, Durham, United Kingdom



hospitalisation, mortality, prognostic factors, SARS-CoV-2, smoking


Introduction: Severe acute respiratory syndrome (SARS-CoV-2) infection causes substantial mortality in hospitalised patients. The purpose of this study was to investigate mortality and identify prognostic factors from the data collected on hospital admission.

Methods: This was a retrospective cohort study of patients hospitalised with clinically suspected and/or laboratory confirmed SARS-CoV-2 infection. The primary outcome was mortality 30 and 90 days after admission. Risk factors for death were identified by multivariable logistic regression.

Results: Three hundred and thirty-four patients were included; 93.4% of patients had positive SARS-CoV-2 RT-PCR swab; median (IQR) age 75 (63–84) years, male 54.2%, smoking (≥ 5 CPD/ ≥5 pack years) 37.1%, obesity 24.8% and frailty 42%. Mortality was 30.8% at 30 days after admission and 34% at 90 days after admission. Mortality was greatest in older patients (age >65 years; 36.7 vs. 16.5%; P < 0.001), particularly older males (age >65 years; male 42.5 vs. female 30%; P = 0.046); smoking (41.1 vs. 24.8%; P = 0.003); younger smokers (age ≤ 65 years; 35.3 vs. non-smoker 6.5%; P < 0.001); with chronic kidney disease (CKD: 50 vs. 27.8%; P = 0.003), chronic neurological disease (43.8 vs. 27.2%; P = 0.007), COPD (41.3 vs. 28.8%; P = 0.048), cardiac disease (40.7 vs. 25.1%; P = 0.003), frailty (44.3 vs. 21%; P < 0.001), and with chest x-ray changes of COVID-19 (39 vs. 13.2%; P < 0.001). Mortality was associated with raised C-reactive protein (CRP) and lymphopaenia on admission. Independent predictors of mortality were (adjusted OR; 95% CI): age (1.05; 1.02–1.08), smoking (2.08; 1.19–3.63); CKD (2.32; 1.09–4.92), chronic neurological disease (2.27; 1.17–4.40), frailty (1.92; 1.047–3.53); chest x-ray changes of COVID-19 (4.31; 2.12–8.79) and Log-CRP (3.21; 1.43–7.22); ROC analysis AUC 0.811 (0.765–0.852).

Conclusion: Mortality for patients hospitalised with SARS-CoV-2 infection is high (>30%) with greatest risk in older-age males with chronic disease and frailty. A history of moderate–heavy smoking is a major risk factor, particularly in younger patients (≤ 65 years). Chest x-ray changes of COVID-19 and raised CRP are clinically valuable prognostic indicators.


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How to Cite

Murphy, S. A., Khalil , F., Fayaz, M. . . ., Robinson, L. ., & Cummings, N. M. (2021). Mortality 30 and 90 days after hospitalisation for COVID-19: prognostic factors on admission to hospital. Journal of Global Medicine, 1(1), e13.



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