title: Low levels of 25(OH)D and insulin-resistance: 2 unrelated features or a cause-effect in PCOS?
abstract: OBJECTIVE
  Recent investigations have identified low vitamin D status as a hypothetical mechanism of insulin-resistance in Polycystic Ovary Syndrome (PCOS). Instead, some authors supported the hypothesis that low vitamin D levels and insulin-resistance are 2 unrelated features of body size in PCOS. Hence, we aimed to explore the association of 25-hydroxyvitamin D (25(OH)D) with anthropometric, metabolic and hormonal features in PCOS.
  
  
  METHODS
  We assessed the association of low 25(OH)D levels with endocrine parameters, insulin-sensitivity evaluated by hyperinsulinemic euglycemic clamp (HEC) and body composition measured by DEXA in 38 women affected by PCOS.
  
  
  RESULTS
  Low 25(OH)D (25(OH)D < 50 nmo/L) was detected in 37% of the entire cohort of patients. Body Mass Index (BMI), in particular total fat mass (p < 0.001), resulted to be the most predictor factor of 25(OH)D levels whereas Sex Hormone Binding Globulin (SHBG), Free Androgen Index (FAI), glucose uptake and fat free mass were not.
  
  
  CONCLUSIONS
  Our data demonstrated that in PCOS low 25(OH)D levels are significantly determined by the degree of adiposity.
authors.affiliation: Endocrinologia e Malattie del Metabolismo, Università Cattolica del Sacro Cuore, Rome, Itlay. giovanna.muscogiuri@gmail.com
authors.forename: Giovanna
authors.initials: G
authors.lastname: Muscogiuri
authors.forename: Caterina
authors.initials: C
authors.lastname: Policola
authors.forename: Annamaria
authors.initials: A
authors.lastname: Prioletta
authors.forename: Gianpio
authors.initials: G
authors.lastname: Sorice
authors.forename: Teresa
authors.initials: T
authors.lastname: Mezza
authors.forename: Annapia
authors.initials: A
authors.lastname: Lassandro
authors.forename: Silvia
authors.initials: S
authors.lastname: Della Casa
authors.forename: Alfredo
authors.initials: A
authors.lastname: Pontecorvi
authors.forename: Andrea
authors.initials: A
authors.lastname: Giaccari
mesh_terms: D000328:Adult; D000886:Anthropometry; D001786:Blood Glucose / Q000032:analysis; D001823:Body Composition; D005260:Female; D015309:Glucose Clamp Technique / Q000379:methods; D006801:Humans; D007333:Insulin Resistance; D015999:Multivariate Analysis; D011085:Polycystic Ovary Syndrome / Q000209:etiology / Q000503:physiopathology*; D012044:Regression Analysis; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives; D014808:Vitamin D Deficiency / Q000150:complications / Q000503:physiopathology*; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D012738:Sex Hormone-Binding Globulin; D014807:Vitamin D; C104450:25-hydroxyvitamin D