title: Ferritin concentrations, metabolic syndrome, and type 2 diabetes in middle-aged and elderly chinese.
abstract: BACKGROUND
  Elevated ferritin concentrations frequently cluster with well-established risk factors of diabetes including obesity, metabolic syndrome, chronic inflammation, and altered circulating adipokines. Few studies, however, have systematically evaluated the effect of these risk factors on ferritin-diabetes association, particularly in Chinese populations.
  
  
  OBJECTIVE
  We aimed to investigate, in a middle-aged and elderly Chinese population, whether elevated ferritin concentrations are associated with higher risk of metabolic syndrome and type 2 diabetes and to what extent the associations were influenced by obesity, inflammation, and adipokines.
  
  
  METHODS
  We conducted a population-based, cross-sectional survey of 3,289 participants aged 50-70 yr in Beijing and Shanghai in 2005. Fasting plasma ferritin, glucose, insulin, lipid profile, glycohemoglobin, inflammatory markers, adipokines, and dietary profile were measured.
  
  
  RESULTS
  Median ferritin concentrations were 155.7 ng/ml for men and 111.9 ng/ml for women. After multiple adjustment, the odds ratios (ORs) were substantially higher for type 2 diabetes (OR 3.26, 95% confidence interval 2.36-4.51) and metabolic syndrome [OR 2.80 (95% confidence interval 2.24-3.49)] in the highest ferritin quartile compared with those in the lowest quartile. These associations remained significant after further adjustment for dietary factors, body mass index, inflammatory markers, and adipokines.
  
  
  CONCLUSIONS
  Elevated circulating ferritin concentrations were associated with higher risk of type 2 diabetes and metabolic syndrome in middle-aged and elderly Chinese independent of obesity, inflammation, adipokines, and other risk factors. Our data support the crucial role of iron overload for metabolic diseases, even in a country with relatively high prevalence of iron deficiency.
authors.affiliation: Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, 294 Tai-Yuan Rd., Shanghai 200031, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Sun
authors.forename: Oscar H
authors.initials: OH
authors.lastname: Franco
authors.forename: Frank B
authors.initials: FB
authors.lastname: Hu
authors.forename: Lu
authors.initials: L
authors.lastname: Cai
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Yu
authors.forename: Huaixing
authors.initials: H
authors.lastname: Li
authors.forename: Xingwang
authors.initials: X
authors.lastname: Ye
authors.forename: Qibin
authors.initials: Q
authors.lastname: Qi
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: An
authors.initials: A
authors.lastname: Pan
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Xu
authors.initials: X
authors.lastname: Lin
mesh_terms: D054392:Adipokines / Q000378:metabolism; D050154:Adiposity / Q000502:physiology; D000368:Aged; D000740:Anemia / Q000150:complications; D001786:Blood Glucose / Q000378:metabolism; D002681:China / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000378:metabolism*; D005260:Female; D005293:Ferritins / Q000378:metabolism*; D006801:Humans; D007249:Inflammation / Q000473:pathology; D019190:Iron Overload / Q000378:metabolism; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology / Q000378:metabolism*; D008875:Middle Aged; D016017:Odds Ratio
chemical_list: D054392:Adipokines; D001786:Blood Glucose; D005293:Ferritins