ULTRASONOGRAPHY OF CAROTID ARTERY IN HEMODIALYSIS (HD) PATIENTS:INTIMA-MEDIA (CIMT) THICKNESS ARE RELATED TO DISORDERS OF MINERAL METABOLISM AND INFLAMMATION, BUT NOT HYPERHOMOCYSTEINEMIA

Purpose: Traditional risk factors for cardiovascular disease (CVD) can not explain the excess mortality and morbility in HD patients (pts).This amplification in CVD risk in uremic pts has been attributed to several emerging risk factors, such as oxidant stress, hyperhomocysteinemia, hyperphosphatemia, chronic low-grade inflammation, and arteriosclerosis vessel stiffening. The aim of our study was to evaluate if there was an association between the extent of the CIMT and some of the main emerging risk factors for atherosclerosis in HD pts.

Methods and Materials: 127 pts underwent bilateral B-mode ultrasonography of the carotid artery for the evaluation of CIMT (mm) and biochemical analysis of sCa, sPO4, albumin, cholesterol, HDL, LDL, triglycerides, homocystein (Hcy), C-reactive protein (CRP), fibrinogen, PTH, folic acid, and vitamin B12. Mean intake of calcium salts and vitamin D were recorded in all pts. The CIMT was correlated with age, sPO4, Ca x PO4 product, HDL, CRP, and diastolic blood pressure (r=.514, P<.000; r=.233, P<.01; r=.264, P<.01; r=-.253, P<.01; r=.311, P<.001; r=-.197, P<.05; respectively).

Results: Patients with age >60 years showed CIMT values higher than pts with age <60 years (1.13±.58 vs. 1.80±.69mm, P<.001). Patients with sPO4 >5.5mg/dl, Ca x PO4 >55 mg2/dl2, PTH >200 pg/ml, and CRP > normal values compared with pts who showed these parameters within normal range have CIMT values significantly higher (1.68±.71 vs. 1.28±.67mm, P<.001; 1.78±.71 vs. 1.32±.67mm, P<.001; 1.58±.79 vs. 1.27±.45, P<.01; 1.91±.82 vs. 1.34±.62, P<.001; respectively). Homocystein levels did not show any correlation with CIMT, and when pts were subdivided into normal or high hcy values or stratified for different hcy levels there were no differences in CIMT values between groups, nevertheless pts with higher hcy levels showed lower folic acid values. We did not find any relationship between amount of calcium salts and vitamin D intake and the extent of CIMT.

Conclusions: Taken together, our results suggest that among the main emerging risk factors for CVD calcium-phosphorus derangement and inflammation are associated with a greater atherosclerotic damage, as indicated by the extent of CIMT, while hyperhomocysteinemia does not seem to be related to this event. Nevertheless, because most of our pts have hyperhomocystinemia we can rule out a role of hyperhomocysteinemia in the atherosclerotic process, so that needs further investigations.