title: [Correlation study between obesity and dawn phenomenon in patients with type 2 diabetes].
abstract: OBJECTIVE
  To investigate the correlation between the frequency of dawn phenomenon and obesity in patients with type 2 diabetes.
  
  
  METHODS
  This study was conducted in 98 patients with type 2 diabetes admitted to the Metabolic Disease Hospital of Tianjin Medical University from 2011 to 2014. The subjects were divided into 3 groups according to BMI: the normal weight (BMI 18.5-23.9 kg/m(2), n = 30), the overweight(BMI 24-27.9 kg/m(2), n = 33)and the obesity (BMI ≥ 28.0 kg/m(2), n = 35). All participants underwent continuous glucose monitoring for 72 h. Fasting plasma glucose(FPG), insulin and C-peptide were tested. Frequency of dawn phenomenon among the 3 groups was calculated, and the correlations between dawn phenomenon and its related factors were analyzed.
  
  
  RESULTS
  The frequency of dawn phenomenon in type 2 diabetes increased with the increase of BMI in the 3 groups (P < 0.05) with 33.3% in the normal weight, 78.8% in the overweight and 88.6% in the obesity groups, respectively. The dawn phenomenon was positively correlated with BMI (r = 0.424, P < 0.05), Homeostasis model assessment of insulin resistance(HOMA-IR) (r = 0.781, P < 0.05), waist circumference (r = 0.394, P < 0.05), fasting C-peptide (r = 0.254, P < 0.05)and TG (r = 0.220, P < 0.05). It was negatively correlated with the course of diabetes mellitus (r = -0.278, P<0.05) and HDL-C (r = -0.268, P < 0.05). No correlation could be viewed between the dawn phenomenon and age, LDL-C, glycosylated hemoglobin A1c(HbA1c), TC and FPG (P > 0.05).
  
  
  CONCLUSIONS
  The dawn phenomenon is closely associated with obesity and insulin resistance. The frequency of dawn phenomenon increases with BMI.
authors.affiliation: Department of Diabetic Nephrology, the Metabolic Disease Hospital of Tianjin Medical University, Key Laboratory of the Ministry of Health of Hormones and Development, Tianjin 300070, China.
authors.forename: Zhenhong
authors.initials: Z
authors.lastname: Guo
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.forename: Jingyu
authors.initials: J
authors.lastname: Wang
authors.forename: Fei
authors.initials: F
authors.lastname: Han
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: X iaoyun
authors.initials: Xi
authors.lastname: Yang
authors.forename: Shaohua
authors.initials: S
authors.lastname: Yang
authors.forename: Bai
authors.initials: B
authors.lastname: Chang
authors.forename: Juhong
authors.initials: J
authors.lastname: Yang
authors.forename: Chunyan
authors.initials: C
authors.lastname: Shan
authors.forename: Liming
authors.initials: L
authors.lastname: Chen
authors.forename: Baocheng
authors.initials: B
authors.lastname: Chang
authors.forename: Yanguang
authors.initials: Y
authors.lastname: Xu
mesh_terms: D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D009765:Obesity / Q000150:complications*; D050177:Overweight / Q000150:complications*; D055105:Waist Circumference
chemical_list: D006442:Glycated Hemoglobin; D007328:Insulin