title: 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.
  
  
  METHODS
  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 mm (10·6 ± 0·1 mg/dl), PTH 10·5 ± 0·7 pm (99 ± 7 pg/ml), 25-hydroxyvitamin D (25OHD) 70·3 ± 3·7 nm (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 months: 4·38 ± 0·83%, P = 0·72; 12 months: 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 months: 3·18 ± 0·79%, P = 0·02 vs baseline; 12months: 3·68 ± 1·22%, P = 0·04 vs baseline). Baseline calcium, PTH and 25OHD levels did not differ between those with abnormal vs normal FMD, nor did these indices predict postoperative change in FMD.
  
  
  CONCLUSIONS
  FMD is generally normal in patients with mild PHPT and is unchanged 1 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.
authors: Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
authors: A L
authors: AL
authors: Carrelli
authors: M D
authors: MD
authors: Walker
authors: M R
authors: MR
authors: Di Tullio
authors: S
authors: S
authors: Homma
authors: C
authors: C
authors: Zhang
authors: D J
authors: DJ
authors: McMahon
authors: S J
authors: SJ
authors: Silverberg
mesh_terms: D000328:Adult; D050197:Atherosclerosis / Q000209:etiology; D002318:Cardiovascular Diseases / Q000209:etiology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D005260:Female; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000150:complications / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D016105:Parathyroidectomy; D012307:Risk Factors; D014664:Vasodilation