Demographic risk factors for COVID-19 infection, severity, ICU admission and death: a meta-analysis of 59 studies

Bart G Pijls*, Shahab Jolani, Anique Atherley, Raissa T Derckx, Janna I R Dijkstra, Gregor H L Franssen, Stevie Hendriks, Anke Richters, Annemarie Venemans-Jellema, Saurabh Zalpuri, Maurice P Zeegers

*Corresponding author for this work

Research output: Contribution to journal(Systematic) Review article peer-review


OBJECTIVE: We aimed to describe the associations of age and sex with the risk of COVID-19 in different severity stages ranging from infection to death.

DESIGN: Systematic review and meta-analysis.

DATA SOURCES: PubMed and Embase through 4 May 2020.

STUDY SELECTION: We considered cohort and case-control studies that evaluated differences in age and sex on the risk of COVID-19 infection, disease severity, intensive care unit (ICU) admission and death.

DATA EXTRACTION AND SYNTHESIS: We screened and included studies using standardised electronic data extraction forms and we pooled data from published studies and data acquired by contacting authors using random effects meta-analysis. We assessed the risk of bias using the Newcastle-Ottawa Scale.

RESULTS: We screened 11.550 titles and included 59 studies comprising 36.470 patients in the analyses. The methodological quality of the included papers was high (8.2 out of 9). Men had a higher risk for infection with COVID-19 than women (relative risk (RR) 1.08, 95% CI 1.03 to 1.12). When infected, they also had a higher risk for severe COVID-19 disease (RR 1.18, 95% CI 1.10 to 1.27), a higher need for intensive care (RR 1.38, 95% CI 1.09 to 1.74) and a higher risk of death (RR 1.50, 95% CI 1.18 to 1.91). The analyses also showed that patients aged 70 years and above have a higher infection risk (RR 1.65, 95% CI 1.50 to 1.81), a higher risk for severe COVID-19 disease (RR 2.05, 95% CI 1.27 to 3.32), a higher need for intensive care (RR 2.70, 95% CI 1.59 to 4.60) and a higher risk of death once infected (RR 3.61, 95% CI 2.70 to 4.84) compared with patients younger than 70 years.

CONCLUSIONS: Meta-analyses on 59 studies comprising 36.470 patients showed that men and patients aged 70 and above have a higher risk for COVID-19 infection, severe disease, ICU admission and death.


Original languageEnglish
Article numbere044640
Number of pages10
JournalBMJ Open
Issue number1
Publication statusPublished - 11 Jan 2021


  • Age Factors
  • COVID-19
  • COVID-19/epidemiology
  • Critical Care
  • Hospitalization
  • Humans
  • Pandemics
  • Risk Factors
  • SARS-COV-2
  • SARS-CoV-2
  • Severity of Illness Index
  • Sex Factors
  • epidemiology
  • infectious diseases

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