Aortic pulse wave velocity is greater in peritoneal dialysis patients with lower dual energy X-ray absorptiometry (DXA) femoral neck bone mineral density.

BACKGROUND: Increased vascular stiffness is associated with low bone mineral density (BMD) in the general population, and both are risk factors for mortality. We wished to determine whether vascular stiffness is associated with BMD in peritoneal dialysis (PD) patients.
METHODS: We measured vascular stiffness by aortic pulse wave velocity (aPWV), BMD by dual electron absorptiometry (DXA) scanning, and body composition using bioimpedance.
RESULTS: We reviewed DXA scans in 125 PD patients, 56.8% male, mean age 64.4 ± 15.3 years, mean aPWV, 10.2 ± 2.6 m/s. We divided patients by aPWV (< 10 and > 10 m/s), and there were no statistical differences in patient demographics, body composition, PD adequacy, peritoneal and urinary calcium losses. On univariate analysis aPWV was negatively associated with total body T score (r = - 0.20, p = 0.037). On multivariable logistic regression patients with higher aPWV were prescribed fewer non-calcium containing phosphate binders, odds ratio (OR) 0.83, 95% confidence interval (CI) 0.70-0.99, p = 0.039, more had lower 25 hydroxy-vitamin D3 concentrations < 50 ng/L (OR 0.34, CI 0.12-0.93, p = 0.035, and lower femoral BMD OR 0.03 (CI 0-0.3.4), p = 0.029, but there was no association with total or lumbar spine BMD.
CONCLUSION: Our study reinforces the hypothesis of a link between bone disease and vascular disease in dialysis patients. As patients with higher aPWV were prescribed fewer non-calcium containing phosphate binders and fewer had higher 25 hydroxy-vitamin D3 concentrations, then this raises the possibility that differences in clinical practice and drug prescribing may help to reduce vascular stiffness, which will require testing in future trials.