INFLUENCE OF BIOCHEMICAL-ALTERATIONS ON ARTERIAL STIFFNESS IN PATIENTS WITH END-STAGE RENAL-DISEASE

The incremental elastic modulus of the common carotid and radial arter ies is increased in patients with end-stage renal disease (ESRD), inde pendently of blood pressure, wall stress, and the presence of atherosc lerotic alterations. Whether biochemical factors may be involved in th e arterial changes and related to renal dysfunction remain largely ign ored. To assess this question, we measured aortic (carotid-femoral), u pper-limb (carotid-radial), and lower-limb (femoral-tibial) pulse wave velocity (PWV) in 74 ESRD patients undergoing hemodialysis in compari son with 57 control subjects similar in age, sex ratio, and mean blood pressure. We evaluated arterial blood pressure by sphygmomanometry, a ortic calcifications and cardiac mass by echography, and routine bioch emical parameters, total plasma homocysteine, and plasma endothelin le vels by standard techniques. In the population of patients with ESRD, on the basis of multiple stepwise regression analysis, aortic PWV was positively and independently correlated with systolic blood pressure ( P<.0001), age (P<.0001), prevalence of aortic calcification (P=.0004), and the prevalence of diabetes mellitus (P=.0043). Upper-limb PWV was influenced exclusively by mean blood pressure (P<.0001). Lower-limb P WV was positively and independently correlated with plasma total homoc ysteine (P=.0004) and plasma endothelin (P=.0187) only. At any vascula r site, PWV was not independently correlated with tobacco consumption; plasma levels of cholesterol, triglyceride, fibrinogen, or hemoglobin ; body mass index; or the presence of bilateral nephrectomy, Finally, plasma homocysteine was independently correlated with cardiac mass (P= .0022). This study provides evidence that in ESRD patients, the stiffn ess of the arterial wall and cardiac mass are strongly influenced by b iochemical factors related to the kidney alterations and are independe nt of age and blood pressure level. Increased plasma endothelin and ho mocysteine may be specifically involved in the vascular damage of lowe r limbs.