Validation of the Entrainment Signal Regularity Index and Associations With Children’s Changes in BMI

Authors

Jennette P Moreno
Kevin M Hannay
Amy R Goetz
Olivia Walch
Philip Cheng

Publication Date

3-1-2023

Journal

Obesity

DOI

10.1002/oby.23641

PMID

36628610

PMCID

PMC9975028

PubMedCentral® Posted Date

3-1-2024

PubMedCentral® Full Text Version

Author MSS

Published Open-Access

yes

Keywords

Humans, Child, Body Mass Index, Exercise, Schools, Childhood Obesity, Body Mass Index, Modeling, Physical Activity

Abstract

Objective: This study examined the validity of a novel metric of circadian health, the Entrainment Signal Regularity Index (ESRI), and its relationship to changes in BMI during the school year and summer.

Methods: In a longitudinal observational data set, this study examined the relationship between ESRI score and children's (n = 119, 5- to 8-year-olds) sleep and physical activity levels during the school year and summer, differences in ESRI score during the school year and summer, and the association of ESRI score during the school year and summer with changes in BMI across those time periods.

Results: The ESRI score was higher during the school year (0.70 ± 0.10) compared with summer (0.63 ± 0.11); t(111) = 5.484, p < 0.001. Whereas the ESRI score at the beginning of the school year did not significantly predict BMI change during the school year (β = 0.05 ± 0.09 SE, p = 0.57), having a higher ESRI score during summer predicted smaller increases in BMI during summer (β = -0.22 ± 0.10 SE, p = 0.03).

Conclusions: Overall, children demonstrated higher entrainment regularity during the school year compared with the summer. During summer, having a higher entrainment signal was associated with smaller changes in summertime BMI. This effect was independent of the effects of children's sleep midpoint, sleep regularity, and physical activity on children's BMI.