Age-dependent association of obesity with COVID-19 severity in paediatric patients

Background: Limited research has addressed the obesity–COVID-19 severity association in paediatric patients. Objective: To determine whether obesity is an independent risk factor for COVID-19 severity in paediatric patients and whether age modifies this association. Methods: SARS-CoV-2-positive patients at NYU Langone Health from 1 March 2020 to 3 January 2021 aged 0–21 years with available anthropometric measurements: weight, length/height and/or body mass index (BMI). Modified log-Poisson models were utilized for the analysis. Main outcomes were 1) hospitalization and 2) critical illness (intensive care unit [ICU] admission). Results: One hundred and fifteen of four hundred and ninety-four (23.3%) patients had obesity. Obesity was an independent risk factor for critical illness (adjusted risk ratio [ARR] 2.02, 95% CI 1.17 to 3.48). This association was modified by age, with obesity related to a greater risk for critical illness in adolescents (13–21 years) [ARR 3.09, 95% CI 1.48 to 6.47], but not in children (0–12 years). Obesity was not an independent risk factor for hospitalization for any age. Conclusion: Obesity was an independent risk factor for critical illness in paediatric patients, and this association was modified by age, with obesity related to a greater risk for critical illness in adolescents, but not in children. These findings are crucial for patient risk stratification and care.