When is the best moment to assess the ankle brachial index: pre- or post-hemodialysis?

Ankle-Brachial Index and Long-Term (10 Years) Survival of Nondiabetic Hemodialysis Patients

Low (<0.9) and high (>1.4) ankle brachial index (ABI) is associated with a higher cardiovascular (CV) mortality in the general and hemodialysis (HD) population. The aim of our study was to determine the impact of ABI on long-term survival of 52 non-diabetic HD patients. The ABI was determined using an automated, non-invasive waveform analysis device. Patients were divided into three groups: low (<0.9), normal (0.9-1.4) and high (>1.4) ABI. Patients were observed from the date of ABI measurement until their death or ten years. Survival analysis showed higher risk for CV death in HD patients with high ABI compared to normal ABI (log rank test P < 0.027). In Cox regression model adjusted for arterial hypertension, smoking, serum cholesterol and triglycerides, high ABI (P < 0.049) remained a predictor of mortality. The results indicate an association between ABI and long-term survival of non-diabetic HD patients and only high ABI was associated with higher CV mortality.

Ankle-brachial index: a simple way to predict mortality among patients on hemodialysis--a prospective study

Background

Ankle-brachial index (ABI) can access peripheral artery disease and predict mortality in prevalent patients on hemodialysis. However, ABI has not yet been tested in incident patients, who present significant mortality. Typically, ABI is measured by Doppler, which is not always available, limiting its use in most patients. We therefore hypothesized that ABI, evaluated by a simplified method, can predict mortality in an incident hemodialysis population.

Methodology/Principal Findings

We studied 119 patients with ESRD who had started hemodialysis three times weekly. ABI was calculated by using two oscillometric blood pressure devices simultaneously. Patients were followed until death or the end of the study. ABI was categorized in two groups normal (0.9–1.3) or abnormal (<0.9 and >1.3). There were 33 deaths during a median follow-up of 12 months (from 3 to 24 months). Age (1 year) (hazard of ratio, 1.026; p = 0.014) and ABI abnormal (hazard ratio, 3.664; p = 0.001) were independently related to mortality in a multiple regression analysis.

Conclusions

An easy and inexpensive technique to measure ABI was tested and showed to be significant in predicting mortality. Both low and high ABI were associated to mortality in incident patients on hemodialysis. This technique allows nephrologists to identify high-risk patients and gives the opportunity of early intervention that could alter the natural progression of this population.