Trends in overweight and socioeconomic inequality among children and adolescents aged 7--18 years in China from 2010--2020

Objectives The aim of this study was to investigate the prevalence of overweight and socioeconomic inequality trends among children and adolescents aged 7–18 years in China from 2010–2020. Methods Data for this study were obtained from the China Family Panel Studies (CFPS), a survey conducted every 2 years between 2010 and 2020, which included a total of 27,703 children and adolescents aged 7 to 18 years. Height and weight were self- or parent/guardian-reported. The prevalence of overweight was calculated on the basis of 3 socioeconomic indicators (father's education level, mother's education level, and household income) via the WHO and Chinese standards, and socioeconomic inequality was quantified via the relative index of inequality (RII). Trends in the RII of prevalence were estimated via sample-weighted linear regression. Results The overall overweight prevalence increased annually from 15.8% in 2010 to 24.8% in 2020, with a higher prevalence in boys and children. Socioeconomic inequality in overweight children and adolescents persisted, with a decrease in socioeconomic inequality for girls in the father's education level subgroup from 1.087–1.016 (p = 0.029). Girls with higher levels of paternal education had a greater risk of being overweight. The RII for boys in the mother's education level subgroup increased from 0.889 to 1.025, and socioeconomic inequality increased (P = 0.038). The high disease risk group among boys reversed from having lower to higher levels of maternal education. In 2020, the RIIs for children and adolescents on the basis of family income, fathers’ education level and mothers’ education level were 0.936, 0.997 and 1.012, respectively. Conclusions This study revealed that the prevalence of overweight among Chinese children and adolescents will continue to increase from 2010–2020 and that socioeconomic inequality in overweight prevalence will increase among boys and decrease among girls. Intervention policies and measures should be developed for high-risk groups to prevent the prevalence of overweight and reduce socioeconomic inequality.