The Metabolic Syndrome and Carotid Intima-Media Thickness in Relation to the Parathyroid Hormone to 25-OH-D Ratio in a General Population

• Published in: American journal of hypertension Vol. 24; no. 1; pp. 102 - 109
• Main Authors: Richart, Tom, Thijs, Lutgarde, Nawrot, Tim, Yu, Jin, Kuznetsova, Tatiana, Balkestein, Elisabeth J, Struijker-Boudier, Harry A, Staessen, Jan A
• Format: Journal Article
• Language: English
• Published: United States 01.01.2011
• Subjects: Adult; Aged; Calcifediol - blood; Female; Humans; Male; Metabolic Syndrome - blood; Metabolic Syndrome - etiology; Metabolic Syndrome - pathology; Middle Aged; Multivariate Analysis; Parathyroid Hormone - blood; Tunica Intima - pathology; Tunica Media - pathology
• DOI: 10.1038/ajh.2010.124
• ISSN: 0895-7061

Parathyroid hormone (PTH) and vitamin D interactively regulate calcium fluxes across membranes, and thereby modulate insulin sensitivity, blood pressure, and arterial calcification. We hypothesized that lower calcium intake as reflected by circulating PTH and 25-OH-D₃ might be associated with the metabolic syndrome (MS) and arterial calcification. In a random population sample (n = 542; 50.5% women; mean age, 49.8 ± 13.1 years), we measured MS prevalence (International Diabetes Federation (IDF) and American Heart Association (AHA) criteria), PTH and 25-OH-D₃, serum and 24-h urinary calcium, MS components, carotid intima-media thickness (CIMT), and calcium intake from dairy products. We assessed associations in multivariable-adjusted analyses, using linear and logistic regressions. The prevalence of MS was 21.0% (IDF criteria) and 23.6% (AHA criteria). MS prevalence, blood pressure, waist circumference, body mass index, fasting blood glucose, insulin and triglycerides, and CIMT increased (P ≤ 0.042) across quartiles of the PTH/25-OH-D₃ ratio, whereas serum and 24-h urinary calcium decreased (P ≤ 0.029). Waist circumference and fasting blood glucose decreased across quartiles of habitual calcium intake (P ≤ 0.04). In models that included MS (IDF) and PTH/25-OH-D₃, the regression coefficients relating CIMT to PTH/25-OH-D₃ ratio and MS were +51 µm (P = 0.013) and +19 µm (P = 0.45), respectively. Multivariable-adjusted analyses were confirmatory. MS prevalence and CIMT were positively associated with PTH/25-OH-D₃. CIMT was not associated with MS. Prospective studies and intervention trials should address the causality of these associations.