title: Lower prediagnostic serum 25-hydroxyvitamin D concentration is associated with higher risk of insulin-requiring diabetes: a nested case-control study.
abstract: OBJECTIVE
  Low serum 25-hydroxyvitamin D [25(OH)D] concentration may increase risk of insulin-requiring diabetes.
  
  
  METHODS
  A nested case-control study was performed using serum collected during 2002-2008 from military service members. One thousand subjects subsequently developed insulin-requiring diabetes. A healthy control was individually matched to each case on blood-draw date (±2 days), age (±3 months), length of service (±30 days) and sex. The median elapsed time between serum collection and first diagnosis of diabetes was 1 year (range 1 month to 10 years). Statistical analysis used matched pairs and conditional logistic regression.
  
  
  RESULTS
  ORs for insulin-requiring diabetes by quintile of serum 25(OH)D, from lowest to highest, were 3.5 (95% CI 2.0, 6.0), 2.5 (1.5, 4.2), 0.8 (0.4, 1.4), 1.1 (0.6, 2.8) and 1.0 (reference) (p                   (trend) <0.001). The quintiles (based on fifths using serum 25(OH)D concentration in the controls) of serum 25(OH)D in nmol/l, were <43 (median 28), 43-59 (median 52), 60-77 (median 70), 78-99 (median 88) and ≥100 (median 128).
  
  
  CONCLUSIONS
  Individuals with lower serum 25(OH)D concentrations had higher risk of insulin-requiring diabetes than those with higher concentrations. A 3.5-fold lower risk was associated with a serum 25(OH)D concentration ≥60 nmol/l.
authors.affiliation: Naval Health Research Center, 140 Sylvester Road, San Diego, CA 92106-3521, USA. Edward.Gorham@med.navy.mil
authors.forename: E D
authors.initials: ED
authors.lastname: Gorham
authors.forename: C F
authors.initials: CF
authors.lastname: Garland
authors.forename: A A
authors.initials: AA
authors.lastname: Burgi
authors.forename: S B
authors.initials: SB
authors.lastname: Mohr
authors.forename: K
authors.initials: K
authors.lastname: Zeng
authors.forename: H
authors.initials: H
authors.lastname: Hofflich
authors.forename: J J
authors.initials: JJ
authors.lastname: Kim
authors.forename: C
authors.initials: C
authors.lastname: Ricordi
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D015994:Incidence; D007328:Insulin / Q000008:administration & dosage*; D008297:Male; D018570:Risk Assessment; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000175:diagnosis*
chemical_list: D007004:Hypoglycemic Agents; D007328:Insulin; D014807:Vitamin D; C104450:25-hydroxyvitamin D