Influence of the COPD Assessment Test respiratory item score on the decision to hospitalize patients with disease exacerbation in a hospital emergency department

Objectives. The COPD Assessment Test (CAT) measures quality of life in patients with chronic obstructive pulmonary disease (COPD) as well as disease impact on activities of daily living. The questionnaire consists of 8 items related to breathing (cough, phlegm, chest tightness, and breathlessness) and other symptoms (low energy level, sleep disturbances, limitations on daily activities, and confidence when leaving the home). We investigated the relative impact of respiratory versus nonrespiratory scoring on the total CAT score at different moments in the course of COPD exacerbations: baseline (24 hours before an exacerbation), during the exacerbation, 15 days later, and 2 months later. To assess the influence of the respiratory item score on decisions to hospitalize patients treated for exacerbated COPD in our hospital emergency department (ED). Methods. Prospective cohort study. We recruited patients who came to our ED for symptoms consistent with exacerbated COPD. Sociodemographic and clinical data were recorded. Clinical information, including treatments started in the ED and CAT scores, were also recorded. The event was defined as highly symptomatic if the patient's score was 3 points or higher on at least 3 of the 4 respiratory items at baseline. The outcome measures for the first objective were the total CAT score and item scores at the 4 time points before (baseline), during (ED), and after the exacerbation. The outcome for the second objective was hospital admission. Results. A total of 587 patients were included. The mean (SD) total CAT score was 13.48 (7.29) at baseline, 24.86 (7.25) in the ED, 14.7 (7.47) at 15 days, and 13.45 (7.36) at 2 months. The respiratory item scores accounted for a mean 53.4% (20.76%) of the total score at baseline and 48.2% (11.47%) of the total score in the ED. Eighty-two patients (14.0%) were classified as being highly symptomatic. A total of 359 (61.2%) were admitted. Predictors of hospital admission were classification as highly symptomatic, odds ratio (OR, 3.045; 95% CI, 1.585-5.852, P < .001), dyspnea at rest (OR, 2.906; 95% CI:1.943-4.346, P < .001), and start of the following treatments in the ED: oxygen therapy (OR, 4.550; 95% CI, 3.056-6.773; P < .0001), diuretic (OR, 1.754; 95% CI, 1.091-2.819; P = .02), and intravenous antibiotics (OR, 1.536; 95% CI, 1.034-2.281; P = .03). The model achieved an area under the receiver operating characteristic curve of 0.80 (95% CI, 0.763-0.836). Conclusions. Hospital admission from the ED is highly likely in patients with COPD exacerbation who have high baseline CAT scores, dyspnea at rest in the ED, and require oxygen therapy, diuretics, or intravenous antibiotics in the ED. The total CAT score and scores on respiratory items provide a tool for tailoring pharmacalogic and nonpharmacologic treaments and can facilitate follow-up evaluations.