Abstract
OBJECTIVES: The aim of this study was to investigate the trends in overweight and the trends in socioeconomic inequality in overweight among Chinese children and adolescents aged 7-18 years in China from 2010 to 2020. METHODS: Data for this study were obtained from the China Family Panel Studies (CFPS), which conducted surveys every 2 years between 2010 and 2020. A total of 27,703 records were included, involving 12,263 children and adolescents aged 7-18 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) using WHO and Chinese standards. According to WHO standards, overweight is defined as a sex- and age-specific BMI-Z score > 1. According to China's WS/T 586-2018 "Screening for Overweight and Obesity in School-Aged Children and Adolescents," overweight is defined as a sex- and age-specific BMI greater than or equal to the corresponding "overweight" threshold. And socioeconomic inequality was quantified by the relative index of inequality (RII). Trends in the RII of prevalence were estimated by sample-weighted linear regression. RESULTS: Between 2010 and 2020, the overall prevalence of overweight among children and adolescents aged 7 to 18 in China continued to rise, increasing from 15.8% in 2010 to 24.8% in 2020. After adjusting for sex and age, it was found that the prevalence rate was higher among boys and children. During the study period, socioeconomic inequalities in overweight among children and adolescents persisted (RII ≠ 1). In the father's educational attainment subgroup, the RII for girls decreased from 1.087 in 2010 to 1.016 in 2020, indicating a narrowing of socioeconomic inequalities (P = 0.029). Girls with higher levels of father's educational attainment had a greater risk of overweight. In the mother's educational attainment subgroup, the RII for boys increased from 0.889 in 2010 to 1.025 in 2020, indicating an expansion of socioeconomic inequality (P = 0.038). The high-risk group for overweight among boys shifted from lower to higher levels of maternal educational attainment. 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 continue to increase from 2010 to 2020 and that socioeconomic inequality in overweight prevalence 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.