title: Serum 25-hydroxyvitamin D levels are inversely associated with systemic inflammation in severe obese subjects.
abstract: Obesity is frequently characterized by a reduced vitamin D bioavailability, as well as insulin-resistance and a chronic inflammatory response. We tested the hypothesis of an independent relationship between serum concentrations of 25-hydroxyvitamin D (25[OH]D) and several circulating inflammatory markers in a cohort of severely obese individuals. Cross-sectional study was carried out among obese patients undergoing a clinical evaluation before bariatric surgery in our University Hospital. Serum 25(OH)D, fasting and post load glucose and insulin, high-sensitive C-reactive protein (hs CRP), fibrinogen, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), leptin, adiponectin and lipid profile were collected. Insulin-resistance was assessed by insulin sensitivity index (ISI). Total body fat (FAT kg), total percent body fat (FAT%) and truncal fat mass (TrFAT) were assessed with dual-energy X-ray absorptiometry. A total of 147 obese subjects (89 women, 37.8 ± 7.1 years) with mean body mass index (BMI) of 43.6 ± 4.3 kg/m(2) were enrolled. Patients in the lowest tertile of 25(OH)D were significantly more obese with a higher amount of TrFAT, more insulin-resistant, and had higher levels of fasting and post-challenge glucose (p < 0.05 for all). In a multivariate regression analysis, serum 25(OH)D was inversely related to significant levels of hs CRP, IL-6 and TNF-α after accounting for age, gender, season of recruitment, BMI, FAT kg and TrFAT (p < 0.01 for all). In extremely obese subjects, 25(OH)D serum concentrations are inversely associated with several biomarkers of systemic inflammation, regardless of the total quantity of fat mass.
authors: Department of Internal Medicine, University of Rome Tor Vergata, Via Montpellier 1, 00133, Rome, Italy.
authors: Alfonso
authors: A
authors: Bellia
authors: Caterina
authors: C
authors: Garcovich
authors: Monica
authors: M
authors: D'Adamo
authors: Mauro
authors: M
authors: Lombardo
authors: Manfredi
authors: M
authors: Tesauro
authors: Giulia
authors: G
authors: Donadel
authors: Paolo
authors: P
authors: Gentileschi
authors: Davide
authors: D
authors: Lauro
authors: Massimo
authors: M
authors: Federici
authors: Renato
authors: R
authors: Lauro
authors: Paolo
authors: P
authors: Sbraccia
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood*; D007333:Insulin Resistance; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D015999:Multivariate Analysis; D009765:Obesity / Q000097:blood*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D014807:Vitamin D; D002097:C-Reactive Protein; C104450:25-hydroxyvitamin D