title: Cardiovascular risk factors and arterial rigidity are similar in asymptomatic normocalcemic and hypercalcemic primary hyperparathyroidism.
abstract: OBJECTIVE
  It is still uncertain whether mild primary hyperparathyroidism (PHPT) carries the same risk for increased cardiovascular (CV) morbidity as the more severe symptomatic form. In recent years, the even more subtle normocalcemic (NC) variant is being increasingly recognized. We sought to compare the prevalence of CV risk factors in patients with NC- and hypercalcemic (HC)-PHPT, and to examine whether they differ on a battery of non-invasive vascular parameters. DESIGN/SUBJECTS/METHODS: A retrospective study of two cohorts of patients with PHPT in a referral center: 32 subjects with NC-PHPT and 81 subjects with HC-PHPT, compared for the presence of clinical and biochemical risk factors, and CV morbidity. Non-invasive parameters of arterial stiffness (augmentation index; pulse wave velocity; and vascular compliance indices, C1 and C2) were extracted from the data of gender- and age-matched subsets of these patients, and were related to those of a group of matched control subjects.
  
  
  RESULTS
  Despite a similar prevalence of hypertension (approximately 62%), hyperlipidemia (approximately 30%), and impaired glucose metabolism in both PHPT groups, CV or cerebrovascular disease was more common in the HC-PHPT group (24.7 vs 3.1%, P=0.007). Arterial stiffness parameters did not differ in the three groups, and were unrelated to serum calcium or parathyroid hormone concentration.
  
  
  CONCLUSIONS
  NC-PHPT and HC-PHPT subjects exhibit similar high rates of traditional CV risk factors, and have comparable indices of arterial stiffness. The lower clinical CV morbidity observed with NC-PHPT remains unexplained, and requires confirmation. Until then, the CV risk associated with NC-PHPT should not be underestimated.
authors.affiliation: The Sackler Faculty of Medicine, Institute of Endocrinology, Metabolism and Hypertension, Tel Aviv Sourasky Medical Center, Tel Aviv University, Tel Aviv, Israel. karentor@tasmc.health.gov.il
authors.forename: Karen M
authors.initials: KM
authors.lastname: Tordjman
authors.forename: Marianna
authors.initials: M
authors.lastname: Yaron
authors.forename: Elena
authors.initials: E
authors.lastname: Izkhakov
authors.forename: Etty
authors.initials: E
authors.lastname: Osher
authors.forename: Galina
authors.initials: G
authors.lastname: Shenkerman
authors.forename: Yonit
authors.initials: Y
authors.lastname: Marcus-Perlman
authors.forename: Naftali
authors.initials: N
authors.lastname: Stern
mesh_terms: D000368:Aged; D001158:Arteries / Q000503:physiopathology*; D001783:Blood Flow Velocity; D002318:Cardiovascular Diseases / Q000209:etiology*; D016022:Case-Control Studies; D003187:Compliance; D004548:Elasticity; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000150:complications*; D049950:Hyperparathyroidism, Primary / Q000150:complications* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011673:Pulsatile Flow; D012189:Retrospective Studies; D012307:Risk Factors