Association and potential mediators between socioeconomic status and childhood obesity in China:findings from a national cohort study / 《全球健康杂志（英文）》

Objective:Socioeconomic status(SES)is associated with childhood obesity,but the underlying factors remain unknown.This study aimed to identify mediators that may explain SES disparities in childhood obesity in China.Methods:Nationally representative longitudinal data from the China Education Panel Survey of 11 019 chil-dren(13.03±0.79)collected from 2013-2014 to 2016-2017 academic years.Overweight/obesity was de-fined using Chinese national body mass index cut-points.Principal component analysis was used to con-vert the four SES indicators(maternal and paternal education,and occupation)into one comprehensive vari-able.Mediation analysis for SES disparities in childhood obesity was conducted using structure equation models.Results:The prevalence of overweight/obesity was 12.8％,and was higher in boys than in girls(17.8％vs.7.6％,P＜0.001)at baseline.Among boys,relative risk(RR)of obesity was 1.23(95％CI:1.09 to 1.40,P＜0.001)for per unit change in SES.There was no significant association between obesity and SES among girls.Mediation analyses showed that among boys,birth weight,being the only child in the family and children's self-perceived weight status mediated 70.0％of the effects of SES on obesity.No mediation effect was detected in girls.Conclusions:Chinese boys are more likely to be overweight or obese than girls.SES may impact childhood obesity through birth weight,being the only child in the family and children's self-perceived body weight status in boys,but not in girls.More attention should be made to address childhood obesity in high SES families among boys.Interventions targeting at these mediators are needed.

Characteristics of sleep among Chinese preschool children born preterm / 中国学校卫生

Objective@#To examine sleep characteristics of preschool children who were born preterm, which could provide a reference for the future intervention in the risk population.@*Methods@#This retrospective cohort study was conducted from March 2017 to November 2018 in hospitals in cities of Guangzhou, Zhongshan, and Shenzhen, Guangdong Province, China, we recruited 202 preschool children aged 4-6 years, including 40 early-and moderate preterm (gestational age <34 weeks), 56 late preterm (34-36 weeks) , and 106 full-term preschool children (≥37 weeks). Caregivers reported children’s sleep time and habits using Chinese version of Children’s Sleep Habits Questionnaire (CSHQ).@*Results@#Compared to the full-term group, the very-or-moderate-preterm group had shorter nighttime sleep duration (9.07±0.75 vs 9.33±0.59 h; adjusted β=-0.33), shorter total sleep duration (10.39±0.86 vs 11.05±1.32 h; adjusted β=-0.70), higher sleep duration score of CSHQ (4.60 ± 1.57 vs 3.97 ± 1.25 points; adjusted β=0.58), and higher sleepdisordered breathing score of CHSQ (3.78±1.27 vs 3.41±0.71 points; adjusted β=0.49). The late preterm group had lower parasomnias score of CSHQ (8.40±1.65 vs 8.75±1.72 points; adjusted β=-0.57), than the full-term group(P<0.05). When gestational age was analyzed as a continuous variable, it was positively associated with the total sleep duration (adjusted β= 0.06), while was inversely associated with sleep-disordered breathing scores of CSHQ (adjusted β=-0.06).@*Conclusion@#Very-or-moderate preterm children have shorter sleep duration and more sleep disordered breathing problems than full-term children, and have more disorders of sleeping duration and sleeping breathing than full-term children, while the late preterm children have less sleeping disorders than full-term children. The children of lower gestational age can have shorter sleep duration and more sleep-disordered breathing which should be addressed in future intervention.