FEV1%pred and BMI are weak predictors for clinical outcome after pulmonary rehabilitation in COP

Abstract

Introduction: Pulmonary rehabilitation (PR) is a fundamental part of the integrated care of people with chronic obstructive pulmonary disease (COPD). Little is known about characteristics which predict PR outcome. Aim: To investigate whether baseline characteristics may predict the clinical response as measured by Clinical COPD Questionnaire (CCQ), COPD Assessment Test (CAT) and Endurance Shuttle Walk Test (ESWT). Method: 352 COPD patients were included in this study. Static and dynamic lungfunction, body mass index (BMI), cycle ergometry with blood gases, incremental shuttle walk test, ESWT, CCQ and CAT were measured at the start of PR. Subjects followed a program with exercise training, education and psychological interventions. After 9 weeks, ESWT, CCQ en CAT were repeated. As a minimal important clinical difference (MCID) we used 0.4 for the CCQ and 2 for the CAT. Results: A small significant correlation (Spearman) was found between Δ ESWT and FEV1%pred (ρ=0.168), between Δ ESWT and BMI (ρ=0.272) and between Δ CCQ and FEV1%pred (ρ=0.219). The proportion of patients improving > MCID was 73% (CAT) and 73% (CCQ). Responders were not different from non-responders with respect to the baseline characterics and PaO2 or PaCO2 values. Conclusion: In our population, FEV1%pred and BMI are weak predictors for the outome of PR.