Amino-terminal pro-B-type natriuretic peptide as predictor of mortality in patients with symptomatic peripheral arterial disease: 5-year follow-up data from the linz peripheral arterial disease study

Abstract

BACKGROUND: Amino-terminal pro-B-type natriuretic peptide (NT-proBNP) has emerged as predictor of mortality endpoints in cardiac disease. In contrast, the prognostic value of NT-proBNP in patients with peripheral arterial disease (PAD) is unclear. Therefore, we aimed to evaluate the capability of NT-proBNP as a marker for long-term prognosis in atherosclerotic PAD. METHODS: We obtained NT-proBNP serum concentrations in 487 consecutive patients with symptomatic PAD admitted to a tertiary-care hospital. The endpoint was defined as all-cause mortality, and the study participants were followed for 5 years. RESULTS: Of the 487 patients enrolled, 114 died and 373 survived during follow-up. The median NT-proBNP concentration was higher among decedents than survivors (692 vs 143 ng/L; P < 0.001). Using the median NT-proBNP concentration of the entire cohort (213 ng/L) as threshold level, Kaplan-Meier curve analysis demonstrated that the survival probability was lower in patients with NT-proBNP above the median (log-rank test, P < 0.001). In the fully adjusted Cox proportional-hazards regression analysis, NT-proBNP >213 ng/L had a risk ratio of 2.27 (95% CI 1.27-4.03; P = 0.005) independent of age, sex, glomerular filtration rate, clinical stage of PAD, cardiovascular comorbidity, and other potential confounders. Further analyses showed that NT-proBNP added significantly to the value of established and emerging outcome predictors of PAD. CONCLUSIONS: In this study, a NT-proBNP serum concentration >213 ng/L was a robust and independent predictor of 5-year all-cause mortality in patients with symptomatic PAD. Thus, NT-proBNP measurements can be considered a valuable tool for risk stratification in these patients. © 2008 American Association for Clinical Chemistry.