title: A simple clinical measure of quadriceps muscle strength identifies responders to pulmonary rehabilitation.
abstract: The aim was to determine if baseline measures can predict response to pulmonary rehabilitation in terms of six-minute walk distance (6MWD) or quality of life. Participants with COPD who attended pulmonary rehabilitation between 2010 and 2012 were recruited. Baseline measures evaluated included physical activity, quadriceps strength, comorbidities, inflammatory markers, and self-efficacy. Participants were classified as a responder with improvement in 6MWD (criteria of ≥25 m or ≥2SD) and Chronic Respiratory Questionnaire (CRQ; ≥0.5 points/question). Eighty-five participants with a mean (SD) age of 67(9) years and a mean forced expiratory volume in one second of 55(22)% were studied. Forty-nine and 19 participants were responders when using the 6MWD criteria of ≥25 m and ≥61.9 m, respectively, with forty-four participants improving in CRQ. In a regression model, responders in 6MWD (≥25 m criteria) had lower baseline quadriceps strength (P = 0.028) and higher baseline self-efficacy scores (P = 0.045). Independent predictors of 6MWD response (≥61.9 m criteria) were participants with metabolic disease (P = 0.007) and lower baseline quadriceps strength (P = 0.016). Lower baseline CRQ was the only independent predictor of CRQ response. A participant with relatively lower baseline quadriceps strength was the strongest independent predictor of 6MWD response. Metabolic disease may predict 6MWD response, but predictors of CRQ response remain unclear.
authors.affiliation: Queensland Lung Transplant Service, The Prince Charles Hospital, Rode Road, Chermside, QLD 4032, Australia ; School of Medicine, The University of Queensland, St Lucia, QLD 4072, Australia ; Physiotherapy Department, The Prince Charles Hospital, Rode Road, Chermside, QLD 4032, Australia.
authors.forename: James R
authors.initials: JR
authors.lastname: Walsh
authors.affiliation: Queensland Lung Transplant Service, The Prince Charles Hospital, Rode Road, Chermside, QLD 4032, Australia ; School of Rehabilitation Sciences and Griffith Health Institute, Griffith University, Parklands Drive, Southport, QLD 4215, Australia.
authors.forename: Norman R
authors.initials: NR
authors.lastname: Morris
authors.affiliation: Discipline of Physiotherapy, The University of Sydney, 75 East Street, Lidcombe, NSW 2141, Australia.
authors.forename: Zoe J
authors.initials: ZJ
authors.lastname: McKeough
authors.affiliation: Queensland Lung Transplant Service, The Prince Charles Hospital, Rode Road, Chermside, QLD 4032, Australia ; School of Medicine, The University of Queensland, St Lucia, QLD 4072, Australia.
authors.forename: Stephanie T
authors.initials: ST
authors.lastname: Yerkovich
authors.affiliation: School of Medicine, The University of Queensland, St Lucia, QLD 4072, Australia.
authors.forename: Jenny D
authors.initials: JD
authors.lastname: Paratz
mesh_terms: D000368:Aged; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D053580:Muscle Strength; D053581:Muscle Strength Dynamometer; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology / Q000534:rehabilitation*; D052097:Quadriceps Muscle / Q000502:physiology*; D020377:Self Efficacy; D016896:Treatment Outcome