A longitudinal analysis comparing the proportion of children with excess weight before and during the COVID-19 pandemic

Abstract

Background: The National Child Measurement Programme (NCMP) reported an increase in the prevalence of children in Reception (4-5 years) and Year 6 (10-11 years) with overweight/obesity during the coronavirus disease 2019 (COVID-19) pandemic compared to the previous year. This prompted us to conduct a longitudinal analysis to compare weight status before and during the pandemic. Methods: We compared the change in overweight/obesity status of children in Year 1 (Y1) (during the pandemic) who had also been measured as part of the NCMP in Reception (the year before the pandemic), with the change in a sample of children during a two-year ‘pre-pandemic’ period. Results: Overweight/obesity increased by 1.2% to 24.8% (p=0.582) between Reception and Y1 in the pre-pandemic group and by 5.4% to 28.5% (p=0.002) in the pandemic group. This was mainly driven by an increase in the proportion of overweight boys in the pandemic group (22% to 30%) compared to the pre-pandemic group rates (~24% at both time-points). Rates in girls increased by 2.0% to 24.8% in the pre-pandemic group and by 3.3% to 27.6% in the pandemic group. A higher proportion of Reception-aged White children in the pre-pandemic group were overweight/obese compared to the pandemic group, but by Y1 the rates were higher in the pandemic group. In children of South Asian (SA) heritage, the proportion with excess weight in Reception was 18.3% in the pre-pandemic group, increasing to 21.6% by Y1. The increase was substantially higher in the pandemic group of SA children, with an increase from 22.9% in Reception to 30.3% by Y1. Conclusions: We observed a marked increase in the proportion of children with an unhealthy body mass index (BMI) during the first year of the pandemic, suggesting that the societal disruptions caused by lockdown may have adversely affected children’s diet and levels of physical activity.