title: Investigating the relationship between precocious puberty and obesity: a cross-sectional study in Shanghai, China.
abstract: Obesity is reported to be closely relevant to early sexual development but the relationship between sexual precocity and obesity or central obesity is still inconsistent, especially in boys. We aimed to investigate the relationship between precocious puberty and obesity as well as central obesity.
  
  
  
  A large population-based cross-sectional study using multistage, stratified cluster random sampling.
  
  
  
  Data from the Shanghai Children's Health, Education and Lifestyle Evaluation (SCHEDULE) study in June 2014.
  
  
  
  17 620 Chinese children aged 6-12 years.
  
  
  
  Obesity was defined by WHO Child Growth Standards. Central obesity was defined by sex-specific waist-to-height ratio (WHtR) cut-offs (WHtR ≥0.48 for boys, WHtR ≥0.46 for girls). Precocious puberty was identified by Tanner stage of breast, pubic hair and testicle development. A χ2test was performed to compare rates. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association between precocious puberty and general obesity and central obesity. Probit analysis was used for estimating the median age at entry into Tanner stage 2 or greater for breast, pubic hair and testicle development. Linear regression was utilised to compare the effects of WHtR and body mass index (BMI) on sex development indicators.
  
  
  
  25.98% and 38.58% of boys with precocious puberty were respectively accompanied by obesity (OR=2.15, 95% CI=1.31 to 3.50) or central obesity (OR=2.10, 95% CI=1.46 to 3.03); meanwhile, 13.86% and 29.42% of girls with precocious puberty were respectively accompanied by obesity (OR=9.00, 95% CI=5.60 to 14.46) or central obesity (OR=5.40, 95% CI=4.10 to 7.12). The median ages of breast, pubic hair and testicle development decreased with BMI increase and median ages of thelarche and testicular development rather than pubarche were earlier in children with central obesity.
  
  
  
  Earlier pubertal development was positively associated with obesity and central obesity in Chinese children.
authors.affiliation: School of Public Health, Shanghai Jiao Tong University, Shanghai, China.|Pediatric Translational Medicine Institute, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Chen
authors.affiliation: Child Health Advocacy Institute, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.|Shanghai Key Laboratory of Children's Environmental Health, Shanghai Jiaotong University School of Medicine Xinhua Hospital, Shanghai, China.
authors.forename: Yunting
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Wanqi
authors.initials: W
authors.lastname: Sun
authors.affiliation: Shanghai Key Laboratory of Children's Environmental Health, Shanghai Jiaotong University School of Medicine Xinhua Hospital, Shanghai, China.|Department of Endocrine and Genetic Metabolic Diseases, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Yanrui
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Yuanjin
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Qinmin
authors.initials: Q
authors.lastname: Lin
authors.affiliation: Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Lixia
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhu
authors.affiliation: Department of Endocrine and Genetic Metabolic Diseases, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Xiumin
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Public Health, Shanghai Jiao Tong University, Shanghai, China liushijian@scmc.com.cn.|Pediatric Translational Medicine Institute, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Shijian
authors.identifier: 0000-0002-7050-463X
authors.initials: S
authors.lastname: Liu
authors.affiliation: Shanghai Key Laboratory of Children's Environmental Health, Shanghai Jiaotong University School of Medicine Xinhua Hospital, Shanghai, China.|Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Fan
authors.initials: F
authors.lastname: Jiang
mesh_terms: D015992:Body Mass Index; D002648:Child; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000453:epidemiology; D056128:Obesity, Abdominal / Q000453:epidemiology*; D016017:Odds Ratio; D015995:Prevalence; D011629:Puberty, Precocious / Q000453:epidemiology*; D017678:Sex Distribution; D065927:Waist-Height Ratio
keywords: EPIDEMIOLOGY; Obesity; PAEDIATRICS; Puberty