Long-term prognostic value of B-type natriuretic peptide in cardiac and non-cardiac causes of acute dyspnoea.

ABSTRACT

BACKGROUND: B-type natriuretic peptide (BNP) levels significantly predict increased risk of death in heart failure. The predictive role of BNP levels in patients with non-cardiac causes of acute dyspnoea presenting to the emergency department is not well characterized. MATERIALS AND METHODS: The B-type natriuretic peptide for Acute Shortness of Breath EvaLuation (BASEL) study enrolled consecutive patients with acute dyspnoea. RESULTS: Cumulative mortality was 14.8%, 33.1% and 51.9% in 452 patients (age 19-97 years; 58% male) within low (< 100 pg mL(-1)), intermediate (100-500 pg mL(-1)) and high (> 500 pg mL(-1)) BNP plasma levels at 18 months of follow-up. BNP classes (point estimate 1.55, 95%CI 1.19-2.03, P = 0.001) in addition to age, increased heart rate and diuretic use emerged as significant predictors for long-term mortality in multivariable Cox regression analyses. The BNP concentration alone had an area under the receiver operating characteristic curve of 0.71 (95%CI 0.66-0.76; P < 0.001) for predicting 18 months mortality. BNP plasma levels independently predicted long-term risk of death in patients with non-cardiac (point estimate 1.72, 95%CI 1.16-2.56; P = 0.007) and with cardiac causes of acute dyspnoea (point estimate 2.21, 95%CI 1.34-3.64; P = 0.002). CONCLUSIONS: BNP levels are strong and independent predictors for long-term mortality in unselected dyspnoeic patients presenting to the emergency department independent from the cause of dyspnoea.