RESEARCH ROUNDUP

In this meta-analysis of 208 studies with 3 550 997 participants from over 32 countries, Sawadogo et al (2022) evaluated the association between overweight or obesity and COVID-19-related hospitalisations (including hospital admission, intensive care unit admission, invasive mechanical ventilation and death). This study is the largest and most comprehensive summary of the association between obesity and COVID-19 outcomes to date.

They found that being overweight increases the risk of COVID-19-related hospitalisations but not death, with obesity and extreme obesity increasing the risk of both COVID-19-related hospitalisations and death. Possible mechanisms by which obesity could increase the risk of severe COVID-19 include first, that adipose tissue could be a reservoir for viral production; second, obesity is linked to impaired immune function weakening the body, which fails to contain viral replication; third, obesity increases inflammation, which may affect lung parenchyma and bronchi; and fourth, obesity lowers lung capacity and reserve thus making ventilation more difficult.