Prognostic value of self-reported subjective exercise capacity in patients with acute dyspnea

Abstract

Abstract Background Quantitative assessment of self-reported exercise capacity as provided by the Duke Activity Status Index (DASI) is a validated measure of exercise capacity in stable ambulatory patients. Objectives This study aimedto test whether the quantification of self-reported exercise capacityusing the DASI may aid physicians in the risk stratification of patients presenting with acute dyspnea to the emergency department (ED). Methods Basics in Acute Shortness of Breath EvaLuation (BASEL V) was a prospective cohort study recruiting dyspneic patients at the ED. The prognostic value and accuracy of theDASI assessed shortly after presentation were quantified using Cox regression analyses and the Area under the curve (AUC). Results Among 1019 patients eligible for this analysis 529 (51.9%) had an adjudicated final diagnosis of acute heart failure, 75 (7.4%) and 297 (29.1%) patients died within 90 and 720 days after presentation. Unadjusted hazard ratios (HR) and multivariable adjusted hazard ratios (aHR) for 90-day and 720-day mortality increased continuously from the fourth (best self-reported exercise capacity) to the first DASI-quartile (worst self-reported exercise capacity). For 720-day mortality in the first quartile theHR was 9.1 (95%-CI 5.5–14.9) (aHR 6.1 [95%-CI 3.7–10.1]), in the second quartile 6.4 (95%-CI 3.9–10.6) (aHR 4.4 [95%-CI 2.6–7.3]), while in the third quartile the HR was 3.2 (95%-CI 1.9–5.5) (aHR 2.4 [95%-CI 1.4–4.0]). The prognostic accuracy of the DASI was moderate-to-high and higher than that of B-type natriuretic peptide (BNP) and NT-proBNP (N-terminal pro-BNP) concentrations, e.g. for 720-day mortality prediction AUC 0.70 versus 0.64, p=0.020; 0.72 versus 0.68, p=0.074. Conclusions Quantification of self-reported subjective exercise capacityusing the DASI provides moderate-to-high prognostic accuracy in patients presenting with acute dyspnea to the ED and may aid physicians in further risk stratification. Funding Acknowledgement Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union, the Swiss National Science Foundation. Duke Activity Status Index