A small reduction in the ankle-brachial index is associated with increased mortality in patients on chronic hemodialysis.

BACKGROUND: High pulse wave velocity (PWV) and a low ankle-brachial index (ABI) are associated with mortality in hemodialysis (HD) patients. Recently, the cardio-ankle vascular index (CAVI) was developed as a novel index of arterial stiffness independent of blood pressure.

METHODS: We compared brachial-ankle PWV (baPWV), the ABI and the CAVI as predictors of mortality in 194 HD patients (age 64 +/- 12 years; time on HD 111 +/- 96 months) during a follow-up period of 39 +/- 4 months (range 31-46).

RESULTS: The ABI was significantly positively correlated with serum albumin and negatively with log-transformed highly sensitive C-reactive protein (p < 0.01), while baPWV and the CAVI were not. Of 194 patients, 39 patients (20.1%) died during the follow-up, 25 (64.1%) of cardiovascular causes. Kaplan-Meier analysis revealed that the patients with an ABI in the lowest tertile (<1.0) had a significantly lower survival rate (p < 0.01). Cox hazards analysis after adjustment for the conventional risk factors revealed that an ABI value in the lowest tertile was a determinant of total mortality when compared with ABI values in the highest tertile [>1.1; hazard ratio 3.50 (95% confidence interval 1.20-10.20); p = 0.02]. In contrast, baPWV and the CAVI were not associated with mortality.

CONCLUSION: These findings suggest that a small reduction in the ABI (<1.0) is an independent predictor of all-cause mortality in chronic HD patients.