Brachial-ankle pulse wave velocity and the cardio-ankle vascular index as a predictor of cardiovascular outcomes in patients on regular hemodialysis

Abstract

Brachial-ankle pulse wave velocity (baPWV) and the cardio-ankle vascular index (CAVI) are both used to evaluate arterial stiffness. The aim of the present study is to determine whether baPWV or CAVI is superior as a marker of arterial stiffness in hemodialysis (HD) patients. Of 194 patients, 59 patients had been excluded from the study due to advanced age over 76 years old (n = 29), or abnormal ankle-brachial pressure index (ABI) (<0.90 or ≥1.30) (n = 30). We then followed the 135 patients (age: 60 ± 11 years, time on HD: 110 ± 93 months) for the 63 ± 4 (55-70) months. Thirty-two (23.7%) patients had expired, 22 of them of cardiovascular (CV) causes. There were 37 fatal and non-fatal CV events. Kaplan-Meier analysis revealed that the patients with the highest tertile of baPWV (≥16.6 m/s) had a significantly lower survival rate (P < 0.01) when compared with the second (13.4 ≤ baPWV < 16.6 m/s) and the lowest tertiles (<13.4 m/s). Cox hazards analysis after adjustment for comorbid risk factors revealed that the top tertile of baPWV was a determinant of CV death (hazards ratio [HR]: 16.9 [1.1-251.8], P < 0.05) In contrast, CAVI did not associate with CV mortality or events. These findings suggest that baPWV is superior to CAVI as a predictor of CV outcomes in patients on regular HD.