Metabolic disease and participant age are independent predictors of response to pulmonary rehabilitation

Abstract

Purpose: The study aims were (1) to determine whether baseline measures-including the Body Mass Index, Airflow Obstruction, Dyspnea, and Exercise Capacity (BODE) index; Age, Dyspnea, and Airflow Obstruction (ADO) index; physical activity; comorbidities (cardiac, metabolic, or musculoskeletal disease); and the number of hospitalizations over the previous 12 months-can predict responders in 6-minute walk distance (6MWD) following pulmonary rehabilitation (PR) and (2) to determine whether different methods in defining improvement in 6MWD affected identifying responders to PR.

Methods: All participants with chronic obstructive pulmonary disease who attended PR at our institution between 2004 and 2009 were evaluated. A participant was classified as a responder with improvement in 6MWD (≥25 m or ≥2 SD of this dataset coefficient of repeatability).

Results: A total of 203 participants (mean age, 68.2 ± 8.7 years; mean predicted forced expiratory volume in 1 second, 52.5 ± 22.4%) were analyzed. One hundred twenty participants (59.1%) had a comorbidity categorized as cardiac, metabolic, or musculoskeletal disease. The binary logistic regression models showed that younger participants (P ≤ .015) and, when using the coefficient of repeatability method (≥60.9 m), participants with metabolic disease (P = .040) were the only independent predictors of response. No other measure, including participant BODE or ADO index scores, contributed to either model.

Conclusion: Identifying responders in exercise capacity following PR remains difficult, with only age and participants with metabolic disease identified as independent predictors.