Correlation of serum phosphate with carotid intimal-medial thickness in chronic kidney disease patients

While increased serum phosphate concentration is a significant risk factor for vascular calcification, it is unclear whether serum phosphate is also a risk factor for increased arterial wall thickness in chronic kidney disease (CKD) patients. Using B-mode ultrasonography, we examined carotid intimal-medial thickness (CIMT) of CKD patients and analyzed risk factors for increased IMT with regard to the effect of serum phosphate. One hundred patients were enrolled (73 patients without diabetes, 27 patients with diabetes; 57 men, 43 women; age, 46.2 ± 15.3 years). CIMT of patients with diabetes was significantly greater than that of patients without diabetes (0.78 ± 0.250 versus 0.66 ± 0.178 mm; P < 0.0001). For the group of all patients, CIMT correlated strongly and significantly with serum phosphate (r = 0.911; P < 0.001). In multiple regression analysis serum phosphate level (β = 0.356; <0.0001) was found to be a significant independent risk factor for increased CIMT, in addition to other independent risk factors, including advanced age, higher systolic blood pressure, urinary albumin and the presence of diabetes (R2 = 0.956; P < 0.00001). In conclusion, high serum phosphate level is a significant and independent factor associated with advanced arteriosclerosis in CKD patients with and without diabetes in addition to advanced age.