Endothelial function in mild primary hyperparathyroidism

Abstract

Background It is not known if endothelial dysfunction, an important early event in the pathogenesis of atherosclerosis, is present in mild primary hyperparathyroidism (PHPT) and if so, whether it improves following parathyroidectomy. Design We measured flow-mediated vasodilation (FMD), which estimates endothelial function by ultrasound imaging, in patients prior to and 6 and 12 months after parathyroidectomy. Results Forty-five patients with mild PHPT [80% female, 61 ± 1 (mean ± SE) years, serum calcium 2.65 ± 0.03 mmoL/L (10.6 ± 0.1 mg/dL), PTH 10.5 ± 0.7 pmol/L (99 ± 7 pg/mL), 25-hydroxyvitamin D (25OHD) 70.3 ± 3.7 nmol/L (28.2 ± 1.5 ng/mL)] were studied. Baseline FMD was normal (4.63 ± 0.51%; reference mean: 4.4 ± 0.1%), and was not associated with serum calcium, PTH, or 25OHD levels. In the group as a whole, FMD did not change after surgery (6 mo: 4.38 ± 0.83%, p=0.72; 12 mo: 5.07±0.74%, p=0.49). However, in those with abnormal baseline FMD (<2.2%; N=15), FMD increased by 350%, normalizing by 6 months after surgery (baseline: 0.81 ± 0.19%; 6 mo: 3.18 ± 0.79%, p = 0.02 versus baseline; 12 mo: 3.68± 1.22%, p = 0.04 versus baseline). Baseline calcium, PTH, and 25OHD levels did not differ between those with abnormal versus normal FMD, nor did these indices predict postoperative change in FMD. Conclusions FMD is generally normal in patients with mild PHPT and is unchanged one year after parathyroidectomy. Although FMD may normalize after surgery in patients with baseline abnormalities, data do not support using endothelial dysfunction as an indicator for parathyroidectomy.

Is primary hyperparathyroidism a cause of endothelial dysfunction?

“…Their study group consisted of 53 patients with PHPT, FMD measurements were lower than the control group, and a significant improvement was detected postoperatively in 20 patients who had undergone surgery . In contrast to our study, studies by Neunteulf, Carrelli and Stamatelopoulos did not show FMD decrements in patients with PHPT . While the two former studies could be criticized concerning the appropriateness of their control groups, the latter study's results cannot be generalized to the entire population as all of the patients were women.…”

Cardiovascular manifestations of primary hyperparathyroidism: a narrative review

“…Contrary to these observations, Carrelli et al demonstrated that FMD was normal in patients with mild PHPT and was unchanged one year after PTx; however, among those who had impaired FMD at baseline, a significant improvement was observed following PTx (66).…”

Atherosclerosis in SLE: a potential role for serum parathormone levels

“…[33][34][35] In addition, PTH has been found to influence the expression of proinflammatory endothelial factors, such as the receptor of advanced glycation end products and interleukin 6 36 and to promote osteoblastic differentiation of endothelial cells through induction of bone morphogenetic proteins. 37 Towards the same direction, arterial wall thickening, 33 endothelial dysfunction, 38 number of stenotic coronary arteries 14 and increase in CVD mortality 15 have been reported in association with high PTH levels. In the current There is ample evidence of 25-OHD involvement in CVD development, 6-8 40 and 25-OHD deficiency has been shown to influence endothelial dysfunction in both animal models 41 and patients with SLE, 42 possibly as a result of increase in interferon activity, 41 43 previously shown to be involved in SLE-related atherosclerosis.…”

“… 33–35 In addition, PTH has been found to influence the expression of proinflammatory endothelial factors, such as the receptor of advanced glycation end products and interleukin 6 36 and to promote osteoblastic differentiation of endothelial cells through induction of bone morphogenetic proteins. 37 Towards the same direction, arterial wall thickening, 33 endothelial dysfunction, 38 number of stenotic coronary arteries 14 and increase in CVD mortality 15 have been reported in association with high PTH levels. In the current study, none of the patients with heightened PTH levels had evidence of primary hyperparathyroidism; advanced age and reduced 25-OHD serum levels seemed to account for these cases.…”