P.070 Arterial Stiffness Alterations During Hemodialysis

Abstract

Arterial stiffness is an independent predictor of cardiovascular morbidity and mortality in hemodialysis (HD) patients. Determinants of arterial stiffness and its change during HD are not well characterized, and it is not known if parameters of calcium-phosphate metabolism predict arterial wall properties.

We measured carotid-femoral pulse wave velocity (PWV) and carotid augmentation index (AI) before and after HD in 96 chronic HD patients using the PulsePen device. Detailed medical history was taken and blood drawn for routine biochemistry before and after HD. Determinants of PWV and AI and their corresponding changes during HD were assessed by stepwise forward multivariate linear regression models.

Mean pre- and postdialysis PWV was 11.0 ± 2.9 and 11.6 ± 2.9 m/s (P = 0.004) respectively. Mean pre- and postdialysis AI was 23.5 ± 12.2 and 22.1 ± 12.4% (P = NS). Significant and independent predictors of predialysis PWV (R for the whole model = 0.79) were higher age, systolic blood pressure and CRP level, lower serum sodium level, and the presence of peripheral artery disease. Predictors of predialysis AI (R = 0.42) were higher systolic blood pressure and higher time averaged creatinine value. The increase in PWV during dialysis was independently associated (R = 0.53) with lower predialysis PWV, higher baseline heart rate, higher urea level and systolic blood pressure change during dialysis. Change in AI during dialysis was significantly and negatively associated (R = 0.55) with predialysis AI and the heart rate change during dialysis.

Our results confirm previously described predictors of PWV and AI. Parameters of calcium-phosphate metabolism do not seem to influence arterial stiffness before or after dialysis. The relation of serum sodium level to predialysis PWV may imply volume overload that is to be explored.