The incremental benefit of a shortness-of-breath biomarker panel in emergency department patients with dyspnea.

OBJECTIVES: The objective was to determine the incremental benefit of a shortness-of-breath (SOB) point-of-care biomarker panel on the diagnostic accuracy of emergency department (ED) patients presenting with dyspnea.

METHODS: Adult ED patients at 10 U.S. EDs with SOB were included. The physician's estimates of the pretest clinical probability of heart failure (HF), acute myocardial infarction (MI), and pulmonary embolism (PE) were recorded using deciles (0%-100%). Blood samples were analyzed using a SOB point-of-care biomarker panel (troponin I, myoglobin, creatinine kinase-myocardial band isoenzyme [CK-MB], D-dimer, and B-type natriuretic peptide [BNP]). Thirty-day follow-up for MI, HF, and PE was performed. Data were analyzed using logistic regression and receiver operating characteristics (ROC) curve analysis.

RESULTS: Of 301 patients, the mean (+/-standard deviation [SD]) age was 61 (+/-18) years; 56% were female, 58% were white, and 38% were African American. Diagnoses included MI (n = 54), HF (n = 91), and PE (n = 16) in a total of 129 (43%) of the patients. High pretest clinical certainty (>or=80%) identified 60 of these 129 (46.5%) cases. The SOB point-of-care biomarker panel identified 66 additional cases of MI (n = 24), HF (n = 31), and PE (n = 11). The overall adjusted sensitivity for any diagnosis was increased from 65% to 70% with the addition of the SOB point-of-care biomarker panel (difference = 5%, 95% CI = -1.1% to 11%) while specificity was increased from 82% to 83% (difference = 1%, 95% CI = -4% to 7%). The model containing pretest probability and the results of the SOB panel had an area under the curve (AUC) of 83.4% (95% CI = 78.4% to 88.5%), which was not significantly better than the AUC of 80.4% (95% CI = 75.1% to 85.7%) for clinical probability alone.

CONCLUSIONS: The addition of the SOB panel of markers did not improve the AUC for diagnosing the combined set of clinical conditions. Using the disease-specific SOB biomarkers increased the sensitivity on a disease-by-disease basis; however, specificity was reduced.