Received 22 February 2008; received in revised form 26 November 2008; accepted 29 December 2008. published online 25 February 2009.
Objective
To examine the relationship between sleep and obesity in children 3 to 4 years old in Shanghai, China.
Study design
A total of 1311 Chinese children from 10 kindergarten classes in Shanghai, aged 3 to 4 years, who were participating in the kindergarten entrance health examination in 2000, were included in the study. Body weight and height were measured, and a questionnaire was given to the children's parents about sleep and physical and social characteristics of the children and their family. The main outcome measure was obesity, defined as body mass index (kg/m2) ≥95th percentile for the children.
Results
Compared with children reporting ≥11 hours of sleep per night, the odds ratio for childhood obesity was 4.76 (95% CI, 1.28-17.69) for children with <9 hours of sleep, and 3.42 (95% CI, 1.12-10.46) for children with 9.0 to 9.4 hours of sleep, after adjustment for age, sex, and other risk factors. Children with caregivers who slept less, who had mothers with higher education, or who co-slept with caregivers had less nighttime sleep than other children.
Conclusion
Short sleep duration is positively associated with obesity in preschool children, and short nighttime sleep duration is significantly related to bedtime and co-sleeping with caregivers.
aDepartment of Child Development and Behavior, Shanghai Children's Medical Center, affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China
bInjury Research Center, Medical College of Wisconsin, Milwaukee, WI, and Zhejiang University School of Medicine, Zhejiang, China
cShanghai Institute for Pediatric Research, Xinhua Hospital affiliated with Shanghai Jiaotong University School of Medicine, Shanghai, China
dDepartment of Pediatrics, University of Nebraska Medical Center, Omaha, NE
Reprint requests: Xiaoming Shen, MD, PhD, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, 1665 Kongjiang Rd, Shanghai, 200092 China
Supported in part by the National Natural Science Foundation (30500410), Shanghai Key Laboratory of Children's Environmental Health (04DZ05904, 06DZ22024), the Key Discipline in Pediatrics of Shanghai Municipal Education Commission (T0204), and the Key Project in Medicine of Shanghai Municipal Bureau of Health (05III002). The study sponsors had no involvement in the study design or the collection, analysis, and interpretation of data. The authors declare no potential conflicts of interest, real or perceived.
ABSTRACT