Mild primary hyperparathyroidism: vitamin D deficiency and cardiovascular risk markers

Abstract

Context: The extent and clinical significance of cardiovascular (CV) abnormalities associated with mild primary hyperparathyroidism (PHPT) are still matters for discussion.

Objective: The main objective of the present study was to evaluate biochemical CV risk markers in PHPT patients before and after parathyroidectomy (PTX) in comparison with controls.

Design and subjects: In a prospective case-control design, 49 patients with PHPT and 49 healthy matched controls were included.

Methods: Blood pressure (BP), 25-OH-D, plasminogen activator inhibitor-1 activity, von Willebrand factor antigen, homocysteine, high-sensitivity C-reactive protein, IGF-I, and lipid profile were evaluated at baseline and 15 ± 4 months after PTX.

Results: At baseline, the level of 25-OH-D was significantly lower in patients compared with controls (40.1 ± 16.5 vs. 64.6 ± 20.8 nmol/liter, P < 0.001) and increased after PTX (58.9 ± 19.5, P < 0.001). Postoperatively, 25-OH-D was inversely correlated to the PTH level (r = -0.34; P < 0.05). Systolic BP (127.2 ± 17.4 vs. 119.3 ± 12.5 mm Hg, P < 0.05) and triglyceride (TG; 1.04 ± 0.60 vs. 0.86 ± 0.43 mmol/liter, P < 0.05) were higher in patients compared with controls and decreased slightly in patients after PTX (BP, 124.4 ± 16.8 mm Hg, and TG, 0.94 ± 0.50 mmol/liter, P < 0.05). Otherwise, there were no intergroup differences in coagulation, inflammatory, metabolic, and lipid status.

Conclusions: Except for a lower 25-OH-D level and slightly higher systolic BP and TG levels, patients with mild PHPT without other CV risk factors did not differ from healthy controls as regards biomarkers predicting CV diseases. PTX had an overall positive effect on TG level, BP, and vitamin D status.