Clinical predictors of the efficacy of a pulmonary rehabilitation programme in patients with COPD
Received 20 August 2008; accepted 27 January 2009. published online 23 March 2009.
Summary
Objectives
To identify predictors of success for an 8week pulmonary rehabilitation programme (PRP) in patients with chronic obstructive pulmonary disease (COPD).
Methods
Sixty patients were stratified in subgroups according to baseline findings: airway obstruction (FEV1 ≥ or <50% pred), pulmonary hyperinflation (TLC > or ≤120% pred), BMI value (BMI > or ≤25), cardiovascular (CV) comorbidity, and resting PaO2 (PaO2 ≥ or <60mmHg). Outcome measurements of PRP were: >54m increase in 6min walking test (6MWT), or >4points reduction in total score of S. George Respiratory Questionnaire (SGRQ). Logistic regression analysis was used.
Results
After PRP there was a significant improvement in exercise tolerance and quality of life, which correlated with baseline FEV1/VC, PaO2, SpO2, 6MWT and SGRQ. SGRQ significantly decreased and 6MWT significantly increased after PRP in all subgroups, except for patients with CV comorbidities. Both univariate and multivariate logistic regression analyses showed that BMI>25 and resting PaO2<60mmHg were independent predictors of PRP efficacy in terms of improvement of 6MWT, but not of SGRQ scores.
Conclusions
Clinical and functional baseline findings do not predict the response to PRP in COPD. The greater efficacy in patients with BMI>25 or with PaO2<60mmHg may be due to a greater deconditioning in overweight patients, and to a larger room for improvement in hypoxemic patients.
ABSTRACT