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COVID-19 Leads to Accelerated Increases in Children's BMI z-Score Gain: An Interrupted Time-Series Study

R Glenn Weaver1, Ethan T Hunt1, Bridget Armstrong1

  • 1Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina.

American Journal of Preventive Medicine
|June 21, 2021
PubMed

Insights

The COVID-19 pandemic accelerated children's Body Mass Index (BMI) z-score changes, indicating unhealthy weight gain. Urgent public health interventions are needed globally to address this trend in pediatric populations.

Area of Science:

  • Pediatric Health
  • Public Health Nutrition
  • Epidemiology

Background:

  • The COVID-19 pandemic presented unprecedented challenges to child health.
  • School closures, food insecurity, and reduced physical activity opportunities may have negatively impacted children's weight status.
  • Understanding these impacts is crucial for developing targeted interventions.

Purpose of the Study:

  • To analyze the impact of the COVID-19 pandemic on children's Body Mass Index (BMI) z-score changes.
  • To quantify the acceleration in BMI z-score change before and during the pandemic year.
  • To identify potential disparities in pandemic-related weight status changes among different child subgroups.

Main Methods:

  • An interrupted time-series study design was employed.
  • Height and weight data were collected from 1,770 children (mean age 8.7 years, 55.3% male, 64.6% Black) annually from 2017 to 2020.
  • Mixed-effects linear regression models estimated yearly BMI z-score changes, with subgroup analyses conducted by sex, race, weight status, and grade level.

Main Results:

  • Children's yearly BMI z-score change significantly accelerated during the COVID-19 pandemic year (+0.31, 95% CI=0.19, 0.44) compared to pre-pandemic years.
  • This acceleration was observed across both girls (+0.33) and boys (+0.29), and across racial groups including Black (+0.41) and White (+0.22) children.
  • Children with normal weight experienced a substantial acceleration in BMI z-score change (+0.58), as did those in lower (+0.23) and upper (+0.42) elementary grades.

Conclusions:

  • The COVID-19 pandemic has led to a significant acceleration in children's BMI z-score, suggesting rapid unhealthy weight gain.
  • These findings highlight the urgent need for global public health interventions to mitigate the adverse effects of the pandemic on pediatric weight status.
  • Further research should explore the long-term consequences and effective strategies for addressing this public health concern.
Abstract

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