title: Association between serum 25-hydroxyvitamin D level and insulin resistance in a rural population.
abstract: OBJECTIVE
  A low serum 25-hydroxyvitamin D [25(OH)D] level in the blood has been correlated with an increased risk of diabetes mellitus; however, the association between serum 25(OH)D level and insulin resistance has not been established in a Korean rural population. The aim of this study was to investigate the independent association between serum 25(OH)D level and insulin resistance in rural Korean adults.
  
  
  METHODS
  This study used data from the Korean Genome Epidemiology Study-Kangwha Study. In the 2011 study, 1200 adults completed health examinations. In an ancillary study, serum 25(OH)D level was measured in a subsample (n=813). After excluding those taking vitamin D supplements, a cross-sectional analysis was carried out on 807 participants (324 men and 483 women) aged 40 to 89 years old. Measured from overnight fasting blood samples, glucose and insulin levels were used to calculate the homeostasis model assessment for insulin resistance (HOMA-IR). Measures of glucose, insulin, and HOMA-IR were log-transformed for parametric tests.
  
  
  RESULTS
  Serum 25(OH)D level was inversely associated with HOMA-IR (β=-0.003, p=0.039) in a univariate analysis. However, the association was not significant after adjustment for sex and age (β=-0.002, p=0.123) or after adjustment for sex, age, body mass index, smoking status, alcohol intake, and regular exercise (β=-0.003, p=0.247).
  
  
  CONCLUSIONS
  Our findings suggest that vitamin D is not independently associated with insulin resistance in Korean men and women.
authors: Department of Public Health, Yonsei University Graduate School, Seoul, Korea.
authors: Bo Mi
authors: BM
authors: Song
authors: Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea. hckim@yuhs.ac; Cardiovascular and Metabolic Diseases Etiology Research Center, Yonsei University College of Medicine, Seoul, Korea.
authors: Hyeon Chang
authors: HC
authors: Kim
authors: Department of Public Health, Yonsei University Graduate School, Seoul, Korea. ; Cardiovascular and Metabolic Diseases Etiology Research Center, Yonsei University College of Medicine, Seoul, Korea.
authors: Dong Phil
authors: DP
authors: Choi
authors: Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: Sun Min
authors: SM
authors: Oh
authors: Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors: Il
authors: I
authors: Suh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D012424:Rural Population; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Vitamin D; epidemiology; insulin resistance