Response of the COPD Assessment Test to pulmonary rehabilitation in unselected chronic respiratory disease

BACKGROUND AND OBJECTIVE: The COPD Assessment Test (CAT) is a recently introduced, simple-to-use health status instrument that takes less time to complete than better-established health status instruments. In chronic obstructive pulmonary disease (COPD) patients, the CAT improves with pulmonary rehabilitation (PR), and changes correlate with improvements in longer-established health status instruments such as the Chronic Respiratory Questionnaire (CRQ). Increasing numbers of non-COPD patients are referred for PR, but it is not known whether the CAT is responsive to PR in these populations. METHODS: The CAT score was prospectively measured in 365 consecutive patients (255 COPD, 110 non-COPD) before and after an 8-week PR programme. Pre to post change in CAT was calculated for COPD and non-COPD patients, and correlated with change in the CRQ. RESULTS: For both non-COPD and COPD patients, there was a similar and significant improvement in the mean (95% confidence interval) CAT score following PR (non-COPD: -2.1 (-1.0, -3.2) vs COPD: -3.0 (-2.2, -3.8); P = 0.19). Change in CAT was significantly correlated with all domains of the CRQ in non-COPD patients (all P < 0.01). CONCLUSIONS: As in COPD patients, the CAT is immediately responsive to PR in non-COPD patients. Even in unselected chronic respiratory disease patients undergoing PR, the CAT is a practical alternative to longer-established health status questionnaires.