Differences in physical activity according to mMRC grade in patients with COPD
Received 1 April 2016
Accepted for publication 3 June 2016
Published 13 September 2016 Volume 2016:11(1) Pages 2203—2208
Checked for plagiarism Yes
Review by Single-blind
Peer reviewers approved by Dr Charles Downs
Peer reviewer comments 4
Editor who approved publication: Dr Richard Russell
Atsushi Hayata,1 Yoshiaki Minakata,2 Kazuto Matsunaga,3 Masanori Nakanishi,1 Nobuyuki Yamamoto1
1Third Department of Internal Medicine, Wakayama Medical University, School of Medicine, Wakayama, 2Department of Respiratory Medicine, National Hospital Organization Wakayama Hospital, Wakayama, 3Department of Respiratory Medicine and Infectious Disease, Graduate School of Medicine, Yamaguchi University, Yamaguchi, Japan
Background: Physical activity (PA) is impaired from the early stages of COPD, is associated with a worsening of disease prognosis, and causes COPD patients to restrict their daily activities in order to avoid breathlessness. The development of a simple tool to estimate physical activity level (PAL) could be useful for the management of COPD.
Objectives: We investigated the differences in PA according to the modified Medical Research Council (mMRC) grade in patients with COPD.
Methods: A cross-sectional study was performed on stable outpatients with COPD. PA was measured for 2 weeks using a triaxial accelerometer, and dyspnea grade was evaluated in all patients using the mMRC scale.
Results: Ninety-eight patients were recruited. Significant differences in PA duration were observed at all intensities according to the mMRC grade. Despite treatment with controller medications, 59.2% of COPD patients had low PAL, which was <1.5 metabolic equivalents multiplied by hour per day. COPD patients with an mMRC grade ≥2, which was the most balanced cutoff point in the receiver operating characteristic curve, showed a higher reduction rate of PAL (80.0% at mMRC grade 2, 71.4% at mMRC grade 3, and 100% at mMRC grade 4).
Conclusion: PA differed according to the mMRC grade, and mMRC grade ≥2 could predict a low PAL. Therefore, assessment of breathlessness by the mMRC questionnaire would be useful to stratify the risks of reduced PA in COPD.
Keywords: accelerometer, questionnaire, dyspnea, METs
This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.Download Article [PDF] View Full Text [HTML][Machine readable]