Pulse wave velocity and vascular calcification at different stages of chronic kidney disease

BACKGROUND: Increased arterial stiffness and vascular calcification have been recognized as important predictors of cardiovascular mortality in patients with chronic kidney disease. METHOD: In order to examine the precise temporal link between aortic stiffness and cardiovascular risk at the earliest stages of chronic kidney disease, we studied a cohort of 150 patients with chronic kidney disease (52 stage 2/3 patients, 51 stage 4/5 patients and 47 stage 5D patients). Each patient underwent a plain, lateral lumbar radiograph and an abdominal and thoracic multislice spiral computer tomography scan in order to identify and quantify aortic and coronary calcifications. Pulse wave velocity was used as a measure of arterial stiffness. RESULTS: Regardless of the disease stage, patients with chronic kidney disease had higher adjusted pulse wave velocity than controls with preserved renal function (14.6 +/- 3.8 vs. 10.7 +/- 1.7 m/s, respectively; P < 0.0001). Regarding aortic calcification, there was a gradual but significant rise in later chronic kidney disease stages. A similar trend was found for coronary calcification. In a multivariate analysis only age, mean arterial pressure, diabetes and the aortic calcification score were independent determinants of higher pulse wave velocity. CONCLUSION: We found that both vascular stiffness and vascular calcification appear early in patients with chronic kidney disease, but only vascular calcification worsens as the disease progresses. The increase of vascular stiffness in adult patients with chronic kidney disease seems to be more related to age, systolic blood pressure, diabetes and vascular calcification than to uremic toxicity.