title: Interactions between general and central obesity in predicting gestational diabetes mellitus in Chinese pregnant women: A prospective population-based study in Tianjin, China.
abstract: BACKGROUND
  The aim of the present study was to define cut-off points of body mass index (BMI) and waist circumference (WC) for gestational diabetes mellitus (GDM) and to investigate any interactions between high BMI and high WC on the risk of GDM in pregnant Chinese women.
  
  
  METHODS
  From 2010 to 2012, 17 803 women in Tianjin, China, who were at 4-12 weeks gestation were recruited to the study. Gestational diabetes mellitus was diagnosed according to the criteria of the International Association of Diabetes and Pregnancy Study Group at 24-28 weeks gestation. Binary logistic regression was used to obtain odds ratios (ORs) and 95% confidence intervals (CIs) while controlling for the confounding effects of traditional risk factors. Restricted cubic spline was used to identify cut-off points of WC and BMI, if any, for GDM.
  
  
  RESULTS
  Gestational diabetes mellitus developed in 1383 (7.8%) women. The risk of GDM increased steeply with increasing WC from ≥78.5 cm and BMI ≥22.5 kg/m2. If BMI <22.5 kg/m2and WC <78.5 cm were used as the reference, BMI between ≥22.5 and <24.0 kg/m2(multivariable OR 1.76; 95%CI 1.47-2.10) and WC between ≥78.5 and <85.0 cm (multivariable OR 1.53; 95%CI 1.31-1.78) were independently associated with increased risks of GDM. In addition, the presence of both BMI ≥22.5 kg/m2and WC ≥78.5 cm further increased the OR to 2.83 (95% CI 2.44-3.28), with significant additive interaction.
  
  
  CONCLUSIONS
  Body mass index ≥22.5 kg/m2and WC ≥78.5 cm measured up to 12 weeks of gestation were independently and synergistically associated with increased risks of GDM in Chinese pregnant women.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Han
authors.affiliation: Department of Women Health, Tianjin Women and Children's Health Center, Tianjin, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Shao
authors.affiliation: Department of Women Health, Tianjin Women and Children's Health Center, Tianjin, China.
authors.forename: Junhong
authors.initials: J
authors.lastname: Leng
authors.affiliation: Department of Women Health, Tianjin Women and Children's Health Center, Tianjin, China.
authors.forename: Cuiping
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Women Health, Tianjin Women and Children's Health Center, Tianjin, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Nankai District Women and Children's Health Center, Tianjin, China.
authors.forename: Guifeng
authors.initials: G
authors.lastname: Liu
authors.affiliation: Heping District Women and Children's Health Center, Tianjin, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Women Health, Tianjin Women and Children's Health Center, Tianjin, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Women Health, Tianjin Women and Children's Health Center, Tianjin, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Department of Medicine and Therapeutics, Hong Kong Institute of Diabetes and Obesity, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China.
authors.forename: Juliana C N
authors.initials: JCN
authors.lastname: Chan
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: Xilin
authors.initials: X
authors.lastname: Yang
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002681:China / Q000453:epidemiology; D016640:Diabetes, Gestational / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D005260:Female; D006801:Humans; D056128:Obesity, Abdominal / Q000150:complications* / Q000503:physiopathology; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D055105:Waist Circumference
keywords: Chinese pregnant women; body mass index; cut-off points; gestational diabetes mellitus; waist circumference; 中国孕妇; 体重指数; 妊娠糖尿病; 截断点; 腰围