Association of bone activity, calcium load, aortic stiffness, and calcifications in ESRD

Abstract

An inverse relationship between arterial calcifications and bone activity has been documented in patients with ESRD. Calcium overload is associated with arterial calcification, which is associated with arterial stiffening. Whether bone activity interacts with calcium load, aortic stiffness, or arterial calcification is unknown. This study assessed the impact of bone activity on the relationships between the dosage of calcium-containing phosphate binders and aortic stiffness (measured by pulse wave velocity) or abdominal aorta calcification score. Aortic stiffness and calcification were both positively associated with calcium load and negatively associated with bone activity. A significant interaction was found between dosage of calcium-containing phosphate binders and bone activity such that calcium load had a significantly greater influence on aortic calcifications and stiffening in the presence of adynamic bone disease. Independent of any other factor, including dosage of calcium-containing phosphate binders, adynamic bone was associated with greater aortic stiffening, suggesting cross-talk between the bone and arterial walls.

Figures

Figure 1.

Histogram showing the number of patients with double tetracycline–labeled surface values.

Figure 2.

Correlations between daily CaCO3 dosage expressed in grams of elemental Ca and AoCS or aortic PWV for patients with active bone and those with ABD.

Figure 3.

Biochemistry and bone histomorphometry differences between patients with active bone and those with ABD.

Figure 4.

Correlations for the entire population (n = 66) between double tetracycline–labeled surfaces and abdominal aortic calcification score or aortic PWV. •, adynamic bone; □, active bone.