Association between serum 25-hydroxyvitamin D and arterial stiffness in non-dialysis-dependent CKD.

Twenty-five-hydroxyvitamin D (25(OH)D) deficiency is common in chronic kidney disease (CKD) population. This study aimed to investigate the association between 25(OH)D and arterial stiffness in patients with non-dialysis-dependent CKD (CKD ND). Two hundred eighty-three patients aged ⩾18 years with CKD ND were divided into two groups: vitamin D deficient (25(OH)D<20 ng/ml) and vitamin D non-deficient (25(OH)D⩾20 ng/ml). Brachial-ankle pulse wave velocity (baPWV), a good marker for arterial stiffness, was calculated. The prevalence of vitamin D deficiency was 58.3% (165/283) and the mean concentration of 25(OH)D was 18±8 ng/ml. 25(OH)D inversely correlated with baPWV. Multiple linear regression analysis showed that vitamin D level was independently associated with baPWV in patients with CKD ND (β=-0.18, P<0.001). The model accounted for 45% (R(2)=0.45) of total variance of baPWV. Vitamin D deficiency is common in CKD ND, and a low 25(OH)D level is significantly associated with increased arterial stiffness.