This community-based cohort study of 387,109 adults in UK found that unhealthy behaviors accounted for up to 51% of the population attributable fraction of severe COVID-19.

Participants were 387,109 men and women (56.4 ± 8.8 yr; 55.1% women) residing in England from UK Biobank study, of whom 760 (0.2%) were hospitalized for COVID-19.

The authors analyzed the health behaviors of these 760 patients, including their smoking history, physical activity, alcohol intake, and obesity.

After adjustment for age, sex and mutually for each lifestyle factor, physical inactivity (Relative risk, 1.32, 95% confidence interval, 1.10, 1.58), smoking (1.42;1.12, 1.79) and obesity (2.05 ;1.68, 2.49) but not heavy alcohol consumption (1.12; 0.93, 1.35) were all related to COVID-19. They also found a dose-response increase in the risk of COVID-19 with less favorable lifestyle scores, such that participants in the most adverse category had 4-fold higher risk (4.41; 2.52–7.71) compared to people with the most optimal lifestyle. C-reactive protein levels were associated with elevated risk of COVID-19 in a dose-dependent manner, and partly (10–16%) explained associations between adverse lifestyle and COVID-19.

These data suggest that adopting lifestyle changes could lower the risk of severe COVID-19 infection.