Obesity is Associated with Poor Covid-19 Outcomes: A Systematic Review and Meta-Analysis

Abstract

Our aim was to assess the association between obesity and the risk of unfavourable outcomes (composite of severe disease and mortality) in inpatients with COVID-19. We conducted a systematic search of databases between December 2019 and 28th June 2020. Studies were included if they reported or allowed estimation of an odds ratio (OR) for unfavourable outcome in obese compared to non-obese patients hospitalised for COVID-19. Twenty cohort studies of 28 355 hospitalised patients with COVID-19 infection were included. Meta-analysis estimated a pooled OR of 2.02 (1.41-2.89, p<0.001) for an unfavourable outcome in obese versus non-obese patients when adjusted for age, sex and co-morbidities. When unadjusted for confounders, the OR for unfavourable outcomes was 1.25 (CI 1.07-1.45, p=0.005). An increased adjusted OR was also seen for death (OR 1.51; CI 1.13-2.21, p=0.006) and severe illness (OR 2.26; CI 1.47-3.48, p<0.001). Compared to a normal BMI, the risk of an unfavourable outcome was increased even in overweight patients, with severe obesity having an escalated risk. Obesity is independently associated with an unfavourable outcome of COVID-19 illness, with obese patients having twice the risk of a composite outcome of severe disease or mortality, and a 50% increased risk of death.