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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Aged, Cross-Sectional Studies, Female, Humans, Male, Metabolic Syndrome, Middle Aged, Vitamin D.
user
Does serum vitamin D concentration predict insulin action or secretion in European subjects with the metabolic syndrome? Context: To investigate the relation between serum concentration of 25-hydroxyvitamin D [25(OH)D] and insulin action and secretion. In a cross-sectional study of 446 Pan-European subjects with the metabolic syndrome, insulin action and secretion were assessed by homeostasis model assessment (HOMA) indexes and intravenous glucose tolerance test to calculate acute insulin response, insulin sensitivity, and disposition index. Serum 25(OH)D was measured by high-performance liquid chromatography/mass spectrometry. The 25(OH)D(3) concentration was 57.1 +/- 26.0 nmol/l (mean +/- SD), and only 20% of the subjects had 25(OH)D(3) levels > or =75 nmol/l. In multiple linear analyses, 25(OH)D(3) concentrations were not associated with parameters of insulin action or secretion after adjustment for BMI and other covariates.
assistant
In a large sample of subjects with the metabolic syndrome, serum concentrations of 25(OH)D(3) did not predict insulin action or secretion. Clear evidence that D vitamin status directly influences insulin secretion or action is still lacking. Final Decision: no