Independent Role of Severe Obesity as a Risk Factor for COVID-19 Hospitalization: A Spanish Population-Based Cohort Study

Objectives This study analyzed the association between severe obesity and coronavirus disease 2019 (COVID-19) hospitalization and severe disease. Methods The incidence of hospitalization for laboratory-confirmed COVID-19 was evaluated in a prospective population-based cohort of 433,995 persons aged 25 to 79 years in Spain during March and April of 2020. Persons with and without class 3 obesity were compared using Poisson regression to estimate the adjusted relative risk (aRR) from class 3 obesity of COVID-19 hospitalization and of severe disease (intensive care unit admission or death). Differences in the effect by age, sex, and chronic conditions were evaluated. Results Individuals with class 3 obesity had a higher risk of hospitalization (aRR = 2.20, 95% CI: 1.66-2.93) and developing severe COVID-19 (aRR = 2.30, 95% CI: 1.20-4.40). In people younger than 50 years, these effects were more pronounced (aRR = 5.02, 95% CI: 3.19-7.90 and aRR = 13.80, 95% CI: 3.11-61.17, respectively), whereas no significant effects were observed in those aged 65 to 79 years (aRR = 1.22, 95% CI: 0.70-2.12 and aRR = 1.42, 95% CI: 0.52-3.88, respectively). Sex and chronic conditions did not modify the effect of class 3 obesity in any of the outcomes. Conclusions Severe obesity is a relevant risk factor for COVID-19 hospitalization and severity in young adults, having a magnitude similar to that of aging. Tackling the current obesity pandemic could alleviate the impact of chronic and infectious diseases.

Automated summary

Severe obesity is a significant risk factor for COVID-19 hospitalization and severity in young adults, especially pronounced in those under 50 years old, with minimal impact on individuals aged 65 to 79 years. Sex and chronic conditions do not modify the effect of class 3 obesity in any outcomes.