Ankle-brachial blood pressure index predicts cardiovascular events and mortality in Japanese patients with chronic kidney disease not on dialysis.

The ankle-brachial blood pressure index (ABPI) has been recognized to have a predictive value for cardiovascular (CV) events and mortality in general or dialysis populations. However, the associations between ABPI and those outcomes have not been fully investigated in predialysis patients. The present study aimed to clarify the relationships between ABPI and both CV events and mortality in Japanese chronic kidney disease (CKD) patients not on dialysis. In this prospective observational study, we enrolled 320 patients with CKD stages 3-5 who were not on dialysis. At baseline, ABPI was examined and a low ABPI was defined as <0.9. CV events and all-cause deaths were examined in each patient. A Cox proportional hazards model was applied to determine the risk factors for CV events, as well as for mortality from CV and all causes. The median follow-up period was 30 months. CV events occurred in 56 patients and all-cause deaths occurred in 48, including 20 CV deaths. Multivariate analysis showed that age and low ABPI were risk factors for CV events. It was demonstrated that age, a history of cerebrovascular disease and low ABPI were determined as independent risk factors for CV mortality. In addition, age, body mass index and low ABPI were independently associated with all-cause mortality. In patients with CKD, low ABPI during the predialysis period is independently associated with poor survival and CV events, suggesting the usefulness of measuring ABPI for predicting CV events and patient survival in CKD.