Admission NT-proBNP levels, renal insufficiency and age as predictors of mortality in elderly patients hospitalized for acute dyspnea.

Background: Assay of baseline B-type peptide (BNP and NT-proBNP) is useful for heart failure (HF) prognostication. In contrast, the prognostic value of NT-proBNP assay performed on admission of elderly subjects for acute dyspnea is uncertain. The aim of this study was to determine the vital prognostic value of NT-proBNP assay and other relevant variables available on admission in elderly patients hospitalized for acute dyspnea.

Methods: 254 patients over 70 years of age who were initially hospitalized with acute dyspnea were prospectively studied. The log-rank test and Cox proportional-hazards regression models were used to determine the prognostic value of NT-proBNP and creatinine clearance, measured within 24 h of initial admission, as well as age, gender, vascular risk factors and other clinical variables.

Results: Mean age was 81+/-7 years, and 52% of the patients were women. During a median follow-up of 34 months, 134 patients (55%) died and 9 patients (4%) were lost to follow-up. The median survival time was 25 months, and almost half the deaths occurred during the first 6 months. In multivariate analysis the following three variables were independently associated with mortality (shown with their accompanying hazard ratios (HR)): NT-proBNP>2856 pg/mL (median), HR=1.6[95%CI:1.3-5.2]; creatinine clearance <30 mL/min, HR=1.7[95%CI:1.2-2.5]; and age>80 years, HR=1.7[95%CI:1.1-2.6]. The median survival time among patients with an admission NT-proBNP level of >2856 pg/mL (median) was 14 months, compared to >36 months in the rest of the population.

Conclusion: The admission NT-proBNP level, age, and creatinine clearance are predictive of vital outcome in elderly patients hospitalized for acute dyspnea.