Diferença mínima detectável, diferença mínima clinicamente importante e responsividade do teste do degrau endurance em pacientes com doença pulmonar obstrutiva crônica

Abstract

Introduction: constant load tests have been shown to be more responsive to demonstrate the results after an intervention. However, laboratory tests and physical space for walking tests are not always available. Therefore, a endurance step test (EST) responsive to pulmonary rehabilitation will be of great clinical use. Objectives: to analyze responsiveness, determine the minimum clinically important difference and the minimum detectable change in the endurance step test after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD). Method: 24 patients diagnosed with COPD underwent spirometry, incremental and constant load tests on a cycle ergometer, incremental step test (MIST), responded to the modified Medical Research Council dyspnea scale, and to the Saint George's Respiratory Questionnaire. The EST was performed with 70%, 80% or 90% of the number of steps obtained in the MIST. Soon after, patients underwent pulmonary rehabilitation for 12 weeks. At the end, they were reevaluated with the tests previously described. Results: There was an increase in the TDE time and in the constant load test on a cycle ergometer after pulmonary rehabilitation (178 ± 201 seconds and 140 ± 253, respectively). EST proved to be responsive to pulmonary rehabilitation with an effect size of 0.75. The minimum detectable change was 159 seconds. The minimum clinically important difference (MCID) for the distribution-based method was 101 seconds and for the anchor-based method, 161 seconds. Conclusion: EST is responsive to pulmonary rehabilitation in patients with COPD. The test has the minimum detectable difference of 159 seconds and the MCID of 161 seconds.