Correlation of vitamin D deficiency and arterial stiffness in patients with chronic kidney disease

Abstract

Objective To evaluate the association between serum 25-hydroxyvitamin D3 [25(OH)D3] and arterial stiffness in patients with chronic kidney disease (CKD). Methods Three hundred patients with CKD were included, and were divided into two groups based on serum 25(OH)D3 levels: vitamin D deficient [25(OH)D3<20 μg/L] and vitamin D non-deficient [25(OH)D3≥20 μg/L]. Brachial ankle pulse wave velocity (baPWV), which reflected arterial stiffness, was calculated using the single-point method. Clinical data were collected in details. Correlation between serum 25(OH)D3 level and baPWV was assessed by the single factor correlation test and multiple linear regression analysis. Results The prevalence of vitamin D deficiency was 62.7%(188/300). The concentration of 25(OH)D3 was (17.62±8.54) μg/L in total patients, but was (12.38±4.55) μg/L and (26.44±6.05) μg/L in the subgroups of vitamin D deficient and non-deficient, respectively(P<0.01). There was a higher value of baPWV in the group of vitamin D deficient than that of vitamin D non-deficient (1 827.34±429.11 vs 1 555.31±353.14, P<0.01). Serum 25(OH)D3 level and baPWV was negatively correlated in total patients(r=-0.38, P<0.01) and each stage of CKD(stage 2-5)[r=-0.30, P<0.05; r=-0.26, P<0.05; r=-0.46, P<0.01; r=-0.57, P<0.01]. Multiple linear regression analysis showed that vitamin D level was independently associated with baPWV(Model 1: β=-0.18, P<0.01; Model 2: β=-0.17, P=0.01). Both models accounted for 50%(R2=0.50) of total variance of baPWV. Conclusions Vitamin D deficiency is common in CKD, and a low 25(OH)D3 level is significantly associated with increased arterial stiffness in these patients. Clinical intervention studies are needed to clarify whether treatment with vitamin D decreases the risk of cardiovascular disease in patients with CKD. Key words: Cardiovascular diseases; Vitamin D deficiency; Arteriosclerosis; Chronic kidney disease; Brachial ankle pulse wave velocity