title: Factor analysis of metabolic syndrome components and predicting type 2 diabetes: Results of 10-year follow-up in a Middle Eastern population.
abstract: BACKGROUND
  The relationship among components of metabolic syndrome (MetS) and their association with diabetes is unclear in West Asia. The aim of the present study was to conduct factor analysis of MetS components and the effect these factors have on the incidence of type 2 diabetes (T2D) in a population-based cohort study of the Tehran Lipid and Glucose Study (TLGS).
  
  
  METHODS
  The present study enrolled 1861 men and 2706 women (20-60 years of age), from Tehran (Iran) who were free of diabetes at baseline and followed them for 10 years. A principal component analysis was performed to extract standardized factors from MetS components. Logistic regression was used to detect associations between the extracted factors and the incidence of diabetes. A propensity score was used to correct differential selection bias resulting from loss to follow-up.
  
  
  RESULTS
  Factor analysis identified three factors (blood pressure, lipids and glycemia). Waist circumference was shared in three all factors. Blood pressure, lipids and glycemia were related to the incidence of diabetes with odds ratios (95% confidence intervals) of 2.23 (1.31-3.78), 1.89 (1.27-3.67), and 7.54 (4.09-13.91), respectively, in men and 2.13 (1.34-3.40), 2.06 (1.35-3.15), and 13.91 (7.29-26.51), respectively, in women for the third versus the first tertile of these standardized factors.
  
  
  CONCLUSIONS
  Central adiposity may have a pivotal role in MetS linking other risk factors together. Glycemia had a high impact on the incidence of diabetes, whereas blood pressure and lipid had a similar moderate effect on the incidence of diabetes.
authors.affiliation: Department of Epidemiology, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Erfan
authors.initials: E
authors.lastname: Ayubi
authors.affiliation: Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Davood
authors.initials: D
authors.lastname: Khalili
authors.affiliation: Department of Clinical Epidemiology, Faculty of Health, Ilam University of Medical Sciences, Ilam, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Delpisheh
authors.affiliation: Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Hadaegh
authors.affiliation: Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Fereidoun
authors.initials: F
authors.lastname: Azizi
mesh_terms: D050154:Adiposity / Q000208:ethnology; D000328:Adult; D018912:Arabs; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure; D016009:Chi-Square Distribution; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis / Q000208:ethnology* / Q000503:physiopathology; D050171:Dyslipidemias / Q000097:blood / Q000208:ethnology; D005163:Factor Analysis, Statistical; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000208:ethnology / Q000503:physiopathology; D015994:Incidence; D007492:Iran / Q000453:epidemiology; D008055:Lipids / Q000097:blood; D016015:Logistic Models; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000175:diagnosis / Q000208:ethnology* / Q000503:physiopathology; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000208:ethnology / Q000503:physiopathology; D016017:Odds Ratio; D025341:Principal Component Analysis; D011379:Prognosis; D057216:Propensity Score; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D055105:Waist Circumference / Q000208:ethnology; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D008055:Lipids
keywords: Tehran Lipid and Glucose Study (TLGS); factor analysis; metabolic syndrome; type 2 diabetes mellitus; 关键词：因素分析，代谢综合征，德黑兰血脂与血糖研究（TLGS）， 2型糖尿病