ABSTRACT Background Adequate sleep duration is a prevention factor for paediatric obesity, but the role of timing is still unclear. Objectives To investigate associations of sleep duration and timing with BMI in a large paediatric database. Methods Medical chart and survey data were collected from 29 409 children aged 2–18 years who attended well‐child visits between Jan 2019 and Dec 2023 (repeated‐measures cross‐sectional design). Logistic and linear mixed effects regression models accounting for repeated measures estimated odds of overweight/obesity and continuous BMI‐for‐age CDC‐based percentiles for each additional/later hour of sleep duration, midpoint (median of bedtime and wake time), and bedtime, adjusted for potential confounders and stratified by age groups. Results Among young children (2–5 years), shorter sleep duration but not sleep timing was related to higher odds of overweight/obesity (21% higher odds with 95% CI: 3% to 36%). In mid‐childhood (6–12 years), shorter sleep duration and later midpoint were associated with higher odds of overweight/obesity (18%, 95% CI = 9%, 26%; 32%, 95% CI = 17%, 49%). Among adolescents (13–18 years), each hour of later sleep midpoint equated to 12% higher odds of living with overweight/obesity (95% CI: 1% to 23%). Linear models were similar. Conclusions Shorter sleep duration at younger ages and later sleep timing in adolescence were associated with higher BMI.
Zhang et al. (Tue,) studied this question.