title: Vitamin D and diabetes in Koreans: analyses based on the Fourth Korea National Health and Nutrition Examination Survey (KNHANES), 2008-2009.
abstract: OBJECTIVE
  A causal relationship between vitamin D deficiency and the incidence of diabetes mellitus has been suggested, but little research has been conducted on the Korean population.
  
  
  METHODS
  We analysed the glucose tolerance status and serum 25-hydroxyvitamin D concentrations in 12263 subjects >19 years old who were registered for the Korea National Health and Nutrition Examination Survey, 2008-2009.
  
  
  RESULTS
  Various demographic variables such as gender, age, season, resident area, physical activity, smoking, alcohol, marital status, education and occupation were associated with serum 25-hydroxyvitamin D concentrations. After adjusting for these variables as confounders, 25-hydroxyvitamin D concentrations in subjects with diabetes were significantly lower than those in subjects with normal glucose tolerance and those with impaired fasting glucose (P=0.005). Compared with the ≥ 75 nmol/l subgroup of serum 25-hydroxyvitamin D concentration, the odds ratios and 95% confidence intervals for diabetes mellitus were 1.206 (95%CI 0.948-1.534) in the 50- to 74-nmol/l subgroup, 1.339 (1.051-1.707) in the 25-to 49-nmol/l subgroup and 1.759 (1.267-2.443) in the <25-nmol/l subgroup. Compared with the serum ≥ 75-nmol/l 25-hydroxyvitamin D subgroup, serum insulin and homeostasis model assessment 2%B, a marker of insulin secretory capacity, were significantly higher, and homeostasis model assessment 2%S, a marker of insulin sensitivity, was significantly lower in the <25- and 25- to 49-nmol/l serum 25-hydroxyvitamin D subgroups than those in the other subgroups (P<0.001).
  
  
  CONCLUSIONS
  The findings suggest that vitamin D deficiency, possibly involving altered insulin sensitivity, is associated with an increased risk for diabetes mellitus in the Korean population.
authors.affiliation: Department of Endocrinology and Metabolism, Kyung Hee University School of Medicine and Research Institute of Endocrinology, Kyung Hee University, Seoul, Korea.
authors.forename: S Y
authors.initials: SY
authors.lastname: Rhee
authors.forename: Y-C
authors.initials: YC
authors.lastname: Hwang
authors.forename: H Y
authors.initials: HY
authors.lastname: Chung
authors.forename: J-T
authors.initials: JT
authors.lastname: Woo
mesh_terms: D000328:Adult; D000368:Aged; D003920:Diabetes Mellitus / Q000097:blood / Q000453:epidemiology*; D005215:Fasting / Q000097:blood; D005260:Female; D018149:Glucose Intolerance / Q000097:blood / Q000453:epidemiology; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance / Q000502:physiology; D000078790:Insulin Secretion; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D007328:Insulin; D014807:Vitamin D; C104450:25-hydroxyvitamin D