title: Anthropometric indices predicting incident type 2 diabetes in an Iranian population: the Isfahan Cohort Study.
abstract: BACKGROUND
  The link between adiposity and type 2 diabetes (T2D) is well known. However, it remains controversial as to which index and cutoff point is the best predictor in different populations.
  
  
  METHODS
  A total of 2981 urban and rural Iranian adults over 35 years of age, and free of cardiovascular disease and diabetes were followed for 7 years. Anthropometric indices included body mass index (BMI), body adiposity index [BAI=(hip circumference/height¹·⁵)-18], waist-to-height ratio (WHtR), waist-to-hip ratio (WHpR), and waist and hip circumferences. T2D was defined as fasting plasma glucose ≥ 126 mg/dL or 2-h post-prandial plasma glucose ≥ 200 mg/dL, or the use of antidiabetic agents. Receiver operating characteristic curve analysis determined the best cutoff point for each adiposity index.
  
  
  RESULTS
  After 7 years of follow-up, 389 new cases of diabetes were found. Most indices were linearly associated with increased risk of diabetes but the best continuous predictor was WHtR in men [odds ratio: 1.10 (95% confidence interval: 1.07-1.12) for one unit] and BMI in women [1.08 (1.04-1.11) for 0.1 kg/m²]. BMI cutoffs of 26 kg/m² in men and 30 kg/m² in women were the best binary predictors in adjusted models, and showed increased T2D risks of 2.91 (2.06-4.12) and 1.94 (1.42-2.66) times, respectively. All central-obesity indices in men and WHpR in women were also significantly associated with T2D independent of BMI. BAI was significantly associated with T2D in men but not in women.
  
  
  CONCLUSIONS
  BMI at the appropriate cutoffs in both genders and WHtR in men and BMI in women as continuous factors were the best predictors of incident T2D in this Iranian population.
authors.affiliation: Cardiovascular Research Center, Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran. Electronic address: talaei@crc.mui.ac.ir.
authors.forename: M
authors.initials: M
authors.lastname: Talaei
authors.forename: M
authors.initials: M
authors.lastname: Sadeghi
authors.forename: T
authors.initials: T
authors.lastname: Marshall
authors.forename: G N
authors.initials: GN
authors.lastname: Thomas
authors.forename: R
authors.initials: R
authors.lastname: Iranipour
authors.forename: N
authors.initials: N
authors.lastname: Nazarat
authors.forename: N
authors.initials: N
authors.lastname: Sarrafzadegan
mesh_terms: D000273:Adipose Tissue; D000328:Adult; D018912:Arabs / Q000706:statistics & numerical data*; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000208:ethnology / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007492:Iran / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D056128:Obesity, Abdominal / Q000150:complications / Q000453:epidemiology* / Q000208:ethnology; D011237:Predictive Value of Tests; D012307:Risk Factors; D012737:Sex Factors; D055105:Waist Circumference; D049629:Waist-Hip Ratio
keywords: Body adiposity index; Central obesity; Diabète de type 2; Indice d’adiposité corporelle; Obésité; Overall obesity; Risk; Type 2 diabetes