Impact of COVID-19 pandemic on physical health amongst children: Difference-in-differences analyses of nationwide school health checkup database

Introduction

The COVID-19 pandemic posed tremendous challenges for children. However, the long-term effects of the pandemic on various aspects of physical health at a national level remain unclear.

Methods

In this retrospective cohort study, we analysed data from nationwide health checkup records amongst children aged 7–15 years. The dataset comprised 3 544 146 records from 393 794 individuals who graduated from junior high school during fiscal years 2007 to 2022. Difference-in-differences (DID) analyses with multiple time periods were used to examine the impact of COVID-19 on physical health outcomes.

Results

Compared with the pre-pandemic period, the COVID-19 pandemic was associated with excess increases in obesity for boys and girls, persisting over the 3 years (+0.42%; [95% CI, 0.23–0.61]). Also, it was associated with excess increases in underweight (+0.28% [0.25–0.32]) and poor visual acuity amongst boys in the 3rd year (+1.80% [1.30–2.30]). There were excess reductions in dental caries (−1.48% [−2.01 to −0.95]), glucosuria (−0.55 [−0.88 to −0.23]) and hematuria (−0.43% [−0.73 to −0.13]) during the 3rd year of the pandemic.

Conclusions

These findings underscore the multifaceted impact of the pandemic on various health indicators for school-aged children. This information could be valuable for public health policy and paediatric healthcare planning in the post-pandemic era.