Correlation between plasma calcium, parathyroid hormone (PTH) and the metabolic syndrome (MetS) in a community-based cohort of men and women

P>Context In recent years, an association has been noted between several abnormalities that characterize the metabolic syndrome (MetS) and primary hyperparathyroidism (pHPT). These abnormalities include dyslipidaemia, obesity, insulin resistance and hypertension. The correlations between plasma calcium, parathyroid hormone (PTH) and the variables in the MetS in a normal population are still unclear. Objective To describe correlations between plasma calcium and PTH and the various abnormalities present in the MetS in a healthy population. Design We studied 1016 healthy individuals from the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) population of 70 years old, by means of plasma analyses of calcium, PTH, creatinine, lipids, insulin and glucose, as well as by standardized blood pressure measurements. Further, body mass index (BMI) and waist circumference were determined. Results The more National Cholesterol Education Program (NCEP) criteria for the MetS that were met, the higher the s-PTH and albumin-corrected s-calcium. Further, positive correlations between plasma calcium and BMI (P = 0 center dot 0003), waist circumference (P = 0 center dot 0009) and insulin resistance (P = 0 center dot 079) were found. PTH and BMI (P < 0 center dot 0001), waist circumference (P < 0 center dot 0001), systolic blood pressure (P = 0 center dot 0034), diastolic blood pressure (P = 0 center dot 0008), serum triglycerides (P = 0 center dot 0003) and insulin resistance (P = 0 center dot 0003) were positively correlated, whereas serum high density lipoproteins (HDL) (P = 0 center dot 036) and PTH were negatively correlated. Conclusions We conclude that PTH correlates with several of the metabolic factors included in the MetS within a normocalcaemic population. In addition, individuals with mild pHPT present significantly more NCEP criteria for MetS. We postulate that increased levels of PTH in pHPT may be associated with the increased cardiovascular morbidity and mortality seen in pHPT.