title: Augmentation of central arterial pressure in mild primary hyperparathyroidism.
abstract: Primary hyperparathyroidism (PHPT) is associated with increased cardiovascular risk, although the mechanisms involved remain unclear. Recent evidence has shown increased pulse pressure to be a powerful predictor of cardiovascular events. As increases in pulse pressure are due largely to arterial stiffening, we measured arterial stiffness in 21 subjects with PHPT (18 women and 3 men; 46-71 yr old) and 21 age- and sex-matched healthy controls using pulse wave analysis, a technique that measures peripheral arterial pressure waveforms and generates corresponding central aortic waveforms. This allows determination of the augmentation of central pressure resulting from wave reflection and augmentation index, a measure of vessel stiffness. Metabolic parameters were also measured. The serum calcium level among PHPT subjects was (mean +/- SD) 2.74+/-0.14 mmol/L. pulse wave analysis showed that both augmentation and the augmentation index were significantly higher in the PHPT group vs. controls [16+/-5 vs. 10+/-4 mm Hg (P < 0.001) and 36+/-9% vs. 25+/-6% (P < 0.001)] despite comparable brachial systolic pressures between groups (136+/-13 vs. 134+/-18 mm Hg). Patients with PHPT had higher fasting serum insulin levels [median (range), 15.8 (7.4-39.4) vs. 11.6 (5.1-23) mU/L; P < 0.05] and triglyceride (1.6+/-0.6 vs. 1.2+/-0.4 mmol/L; P < 0.05), but lower high density lipoprotein cholesterol (1.4+/-0.4 vs. 1.6+/-0.3 mmol/L; P < 0.05). These data indicate that subjects with mild PHPT (calcium, <3.0 mmol/L) have increased arterial stiffness, as evidenced by higher augmentation of central aortic pressures. Enhanced vessel stiffness may arise from a combination of structural and functional vascular changes due to hypercalcemia and/or metabolic abnormalities. Increased vascular stiffness in subjects with PHPT may account in part for the increased cardiovascular risk in this group.
authors.affiliation: Department of Medicine, University Hospital of Wales, Cardiff, United Kingdom.
authors.forename: J C
authors.initials: JC
authors.lastname: Smith
authors.forename: M D
authors.initials: MD
authors.lastname: Page
authors.forename: R
authors.initials: R
authors.lastname: John
authors.forename: M H
authors.initials: MH
authors.lastname: Wheeler
authors.forename: J R
authors.initials: JR
authors.lastname: Cockcroft
authors.forename: M F
authors.initials: MF
authors.lastname: Scanlon
authors.forename: J S
authors.initials: JS
authors.lastname: Davies
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology; D001158:Arteries / Q000473:pathology*; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology*; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000473:pathology* / Q000503:physiopathology*; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D012307:Risk Factors
chemical_list: D001786:Blood Glucose; D008055:Lipids; D010281:Parathyroid Hormone; D002118:Calcium