Effect of Pulmonary Rehabilitation on COPD Assessment Test Items in Individuals Classified as GOLD Group E

Background: A new Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification has been proposed, based also on COPD Assessment Test (CAT). Objectives: The aim of this large, multicenter, retrospective study was to determine the impact of pulmonary rehabilitation (PR) on CAT items in individuals with COPD, GOLD group E, recovering from an exacerbation (ECOPD). As secondary aims, we evaluated whether gender, associated chronic respiratory failure (CRF), and age might influence results. Methods: Data of 2,213 individuals with available paired pre- and post-PR CAT were analyzed. Other common outcome measures were also assessed. Results: After PR, total CAT improved from 20.8 & PLUSMN; 7.8 to 12.4 & PLUSMN; 6.9 (p = 0.000), and 1,911 individuals (86.4%) reached the minimal clinically important difference (MCID). All CAT items improved significantly without any significant difference among them. However, item "confidence with disease" improved significantly more in males than in females (p = 0.009). Total CAT and six out of eight items improved significantly more in individuals with CRF than in those without (all p < 0.001). Total CAT and three items improved significantly more in younger than in older individuals (p = 0.023). Only presence of CRF was significantly associated with the probability of improving total CAT more than the MCID. Conclusion: In individuals with COPD, GOLD group E, recovering from ECOPD, PR improves all CAT items; however, gender, associated CRF and age may influence the effect size, suggesting the need to evaluate all items in addition to total CAT score.