Higher BMI Associated with Worse COVID-19 Outcomes

Pavankumar Kamat


May 04, 2021


  • Body mass index (BMI) demonstrated a J-shaped association with the risk of COVID-19-related hospitalisation and death and a linear association with intensive care unit (ICU) admissions.

  • This risk was more pronounced in younger adults aged <40 years and people of Black ethnicity.

Why this matters

  • Findings highlight the association of excess weight with severe COVID-19 outcomes, which may help inform priority populations for COVID-19 vaccinations.

Study details

  • This prospective, community-based cohort study used de-identified patient-level data from the QResearch database of general practices in England.

  • Data were acquired for 6,910,695 individuals (mean BMI, 26.78 kg/m2) aged between 20 and 99 years.

  • Funding: National Institute for Health Research Oxford Biomedical Research Centre.

Key results

  • Overall, COVID-19 was attributed to 13,503 hospitalisations, 1601 ICU admissions and 5497 deaths.

  • Each BMI unit increase of above 23 kg/m2 was associated with an increased risk of:

  • hospital admissions (adjusted HR [aHR], 1.05; 95% CI, 1.05-1.05);

  • ICU admissions (aHR, 1.10; 95% CI, 1.09-1.10); and

  • death (aHR, 1.04; 95% CI, 1.04-1.05).

  • These outcomes were independent of existing co-morbidities, including type 2 diabetes.

  • The risk of severe COVID-19 outcomes per unit BMI increase was highest in younger adults and decreased with increasing age (P<.0001):

  • In people aged 20-39 years, each BMI unit increase above 23 kg/m2 was associated with an elevated risk of COVID-19-related hospitalisation (aHR, 1.09; 95% CI, 1.08-1.10), ICU admission (aHR, 1.13; 95% CI, 1.11-1.16) and death (aHR, 1.17; 95% CI, 1.11-1.23).

  • People of Black vs White ethnicity had a higher risk (P<.0001) of COVID-19-related hospitalisation and death, but not of ICU admission.


  • Observational design.

  • Fewer people had recent BMI measurements.

  • Possibility of chance findings cannot be excluded.


Gao M, Piernas C, Astbury NM, Hippisley-Cox J, O'Rahilly S, Aveyard P, Jebb SA. Associations between body-mass index and COVID-19 severity in 6·9 million people in England: a prospective, community-based, cohort study. Lancet Diabetes Endocrinol. 2021 Apr 28 [Epub ahead of print]. doi: 10.1016/S2213-8587(21)00089-9. PMID: 33932335. View full text

This clinical summary originally appeared on Univadis, part of the Medscape Professional Network.


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