Parathyroid hormone and calcium are independently associated with subclinical vascular disease in a community-based cohort

Diseases with abnormal levels of parathyroid hormone (PTH) and calcium, such as primary and secondary hyperparathyroidism, are associated with an increased risk of cardiovascular morbidity and mortality. However, there is paucity on the association between calcium, PTH and abnormalities in the vascular system in the general population.

In the PIVUS study (Prospective Investigation of the Vasculature in Uppsala Seniors), a community based cohort of 70-year old men and women (n = 1016), the associations between s-calcium, p-PTH and endothelial function, arterial stiffness and blood pressures were investigated, adjusting for cardiovascular risk factors and mineral metabolism.

In multivariable linear regression models 1 SD increase in calcium was associated with 1.1 units decrease in the stroke volume/pulse pressure ratio and 0.06 decrease in common carotid artery distensibility (p < 0.001) indicative of increased arterial stiffness. Further, calcium was associated with increasing calculated central pulse pressure with 1.3 mmHg elevation per 1 SD increase in calcium (p < 0.05). 1 SD increase in PTH was associated with 1.9 and 1.0 mmHg increase in intra-arterially measured brachial artery systolic and diastolic blood pressures, respectively (p < 0.01), as well as 1.6 and 0.9 mmHg increase in calculated central systolic and diastolic blood pressures (p < 0.05). PTH was not associated with arterial stiffness, endothelial function or pulse pressure.

In a large community-based sample of elderly, calcium was independently associated with increased arterial stiffness, and PTH independently to intra-arterial peripheral and calculated central blood pressures. The findings indicate a possible link between the vasculature and mineral metabolism.