BMI in early adulthood is associated with severe COVID-19 later in life: A prospective cohort study of 1.5 million Swedish men.

Abstract

Overweight and obesity have been identified as risk factors for severe COVID-19; however, prospective cohort studies investigating the association between overweight early in life and severity of COVID-19 are lacking. This study included 1,551,670 Swedish men, born between 1950 and 1987, with BMI registered at age 18 years. They were followed until January 9, 2021. COVID-19 cases and comorbidities were identified through the National Patient, Intensive Care, and Cause of Death registries. Outcomes included the following: 1) hospitalization; 2) intensive care unit admission; and 3) death. The study found 4,315 cases (mean age = 56.4 years [SD 8.8]) of patients hospitalized because of COVID-19, of which 729 were admitted to an intensive care unit, and altogether there were 224 deaths. The risk for hospital admission increased with higher values of BMI at age 18 years, despite adjustment for comorbidities, from an odds ratio (OR) of 1.19 (95% CI: 1.08-1.31) at BMI = 22.5 to 25 to an OR of 1.68 (95% CI: 1.39-2.02) at BMI ≥ 30, compared with BMI = 18.5 to 20. ORs for intensive care unit admission were 1.44 (95% CI: 1.13-1.84) at BMI = 22.5 to 25 and 2.61 (95% CI: 1.73-3.93) at BMI ≥ 30. Higher BMI in early adulthood was associated with severe COVID-19 many years later, with a risk increase starting already at BMI ≥ 22.5. This underlines the necessity of preventive actions against overweight in youth to offer protection against coming viral pandemics.