title: Vitamin D and 1-hour post-load plasma glucose in hypertensive patients.
abstract: BACKGROUND
  A plasma glucose value ≥155 mg/dl for 1-hour post-load plasma glucose during an oral glucose tolerance test (OGTT) is able to identify subjects with normal glucose tolerance (NGT) at high-risk for type-2 diabetes and with subclinical organ damage. We designed this study to address if 25-hydroxyvitamin D [25(OH)D] circulating levels are associated with glucose tolerance status, and in particular with 1-hour post-load plasma glucose levels.
  
  
  METHODS
  We enrolled 300 consecutive Caucasian hypertensive never-treated outpatients (160 men and 140 women, aged 52.9 ± 9.2 years). Subjects underwent OGTT and measurements of 25(OH)D and standard laboratory tests. Estimated glomerular filtration rate (e-GFR) was calculated by CKD-EPI formula and insulin sensitivity was assessed by Matsuda-index.
  
  
  RESULTS
  Among participants, 230 were NGT, 44 had impaired glucose tolerance (IGT) and 26 had type-2 diabetes. According to 1-h post-load plasma glucose cut-off point of 155 mg/dL, we divided NGT subjects into: NGT < 155 (n = 156) and NGT > 155 mg/dL (n = 74).NGT ≥ 155 had higher significant fasting and post-load glucose and insulin, parathyroid hormone and hs-CRP levels than NGT < 155. On the contrary, Matsuda-index, e-GFR, and 25(OH)D were significantly lower in NGT ≥ 155 than NGT < 155 subjects. In the multiple regression analysis, 25(OH)D levels resulted the major determinant of 1-h post-load plasma glucose in all population and in the four groups of glucose tolerance status. In the whole population, Matsuda-index, hs-CRP and e-GFR explained another 12.2%, 6.7% and 1.7% of its variation.
  
  
  CONCLUSIONS
  Our data demonstrate a significant and inverse relationship between 25(OH)D levels and glucose tolerance status, particularly with 1-h post-load glucose.
authors.forename: Angela
authors.initials: A
authors.lastname: Sciacqua
authors.forename: Maria
authors.initials: M
authors.lastname: Perticone
authors.forename: Nadia
authors.initials: N
authors.lastname: Grillo
authors.forename: Tania
authors.initials: T
authors.lastname: Falbo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Bencardino
authors.forename: Elvira
authors.initials: E
authors.lastname: Angotti
authors.forename: Franco
authors.initials: F
authors.lastname: Arturi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Parlato
authors.forename: Giorgio
authors.initials: G
authors.lastname: Sesti
authors.affiliation: Department of Medical and Surgical Sciences, University Magna Græcia of Catanzaro, V,le Europa 88100, Catanzaro, Italy. perticone@unicz.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Perticone
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014807:Vitamin D / Q000097:blood*
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D014807:Vitamin D