Dyspnea in the elderly: Diagnostic contribution of the differentiation index

Abstract

Background Dyspnea is a common disabling symptom of cardiopulmonary diseases and a considerable reason of emergency room (ER) consultation and hospital admission. In elderly patients, it is sometimes difficult to distinguish between the cardiac and the respiratory origin due to critical presentation. The aim of this study was to assess diagnostic accuracy of the dyspnea differentiation index (DDI). Methods This study is a prospective single centre analysis including patients aged over 65 years consulting ER for dyspnea. Sixty-five patients were included over a period of six months. The etiology of the dyspnea was established according to the findings of the echocardiogram. Dyspnea differentiation index (DDI= PRFxSpo2/1000) was calculated for all the patients. Sensibility and specificity were assessed using the ROC curve. Results Mean included patients age was 75±8 years. Sex ratio was 0.85. Dyspnea had cardiac origin in 38.5% and non-cardiac origin in 61.5% of cases. Mean DDI was higher in the cardiac origin group (15.3vs 9.3, p=0.002). the predictive positive value was 71% and the predictive negative value was 86%. The optimal ROC curve cut-off showed DDI sensibility of 80% and specificity of 77.5%. Conclusions DDI is simple tool easy to calculate with satisfactory diagnostic accuracy that may guide the management of critical dyspnea in elderly before the routine investigation. Key words Dyspnea; Elderly; Emergency room; Echocardiography, Index.