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. 2025 May;30(5):408-416.
doi: 10.1111/resp.70003. Epub 2025 Feb 26.

Respiratory Muscle Strength as a Predictor of Exacerbations in Patients With Chronic Obstructive Pulmonary Disease

Yuichiro Furukawa  1   2 , Atsushi Miyamoto  2 , Kazuhisa Asai  2 , Masaya Tsutsumi  2 , Kaho Hirai  2 , Takahiro Ueda  2 , Erika Toyokura  1   2 , Misako Nishimura  2 , Kanako Sato  2 , Kazuhiro Yamada  2 , Tetsuya Watanabe  2 , Tomoya Kawaguchi  2
Affiliations

Respiratory Muscle Strength as a Predictor of Exacerbations in Patients With Chronic Obstructive Pulmonary Disease

Yuichiro Furukawa et al. Respirology. 2025 May.

Abstract

Background and objective: Chronic obstructive pulmonary disease (COPD) is closely related to skeletal muscle dysfunction, and the evaluation of respiratory muscle function has recently been recommended. We aimed to investigate the effects of respiratory muscle dysfunction on clinical outcomes.

Methods: We retrospectively reviewed the medical records of patients with COPD whose respiratory muscle strength was measured between June 2015 and December 2021. We then analysed the effects of respiratory muscle strength on moderate-to-severe exacerbations after adjusting for confounding factors, including sex, age, forced expiratory volume in 1-s percent predicted, hand grip strength, and skeletal muscle mass index. We also compared the temporal relationship between respiratory and systemic skeletal muscle dysfunctions.

Results: Respiratory muscle weakness (RMW) was observed in 48.1% (100) of the 208 patients. Low percent predicted maximal inspiratory pressure was an independent risk factor for moderate-to-severe exacerbations within 1 year in the Cox regression analysis (adjusted hazard ratio per 1 standard deviation increase, 0.521; 95% confidence interval, 0.317-0.856). Approximately half of the patients already exhibited RMW at the mild systemic skeletal muscle dysfunction, while those with sarcopenia had higher RMW rates. More patients with RMW experienced progressive systemic skeletal muscle dysfunction within 1 year compared to those without RMW.

Conclusion: Lower respiratory muscle strength is associated with an increased risk of exacerbation. Respiratory muscle function could serve as a marker of disease status and early prognosis in COPD.

Keywords: chronic obstructive pulmonary disease; exacerbation; respiratory muscle strength; respiratory sarcopenia; sarcopenia; skeletal muscle.

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Conflict of interest statement

Kazuhisa Asai is an Editorial Board member of Respirology and a co‐author of this article. He was excluded from all editorial decision‐making related to the acceptance of this article for publication. The other authors have no conflicts of interest to declare.

Figures

FIGURE 1
FIGURE 1
Kaplan–Meier curve for exacerbation‐free probability among groups with and without RMW adjusted for sex, age, %FEV1, HGS, and SMI. The red and blue curves represent adjusted exacerbation‐free probability for patients without and with RMW, respectively. The group with RMW had more exacerbations than that without RMW in 1 year. %FEV1, forced expiratory volume in 1‐s percent predicted; HGS, handgrip strength; RMW, respiratory muscle weakness; SMI, skeletal muscle mass index.
FIGURE 2
FIGURE 2
The proportion of patients with RMW in each group classified by systemic skeletal muscle function. The sarcopenia group exhibited higher RMW rates compared to the other groups. However, RMW was present in nearly half of the patients, even in the absence of systemic sarcopenia. HGS, handgrip strength; RMW, respiratory muscle weakness; SMI, skeletal muscle mass index. *p value < 0.05.
FIGURE 3
FIGURE 3
Sankey diagram showing the systemic skeletal muscle function change from baseline to 1 year according to respiratory muscle strength. Three patients in the RMW group exhibited decreased systemic skeletal muscle strength or mass in 1 year. Only one patient experienced progression of systemic skeletal muscle dysfunction in the group without RMW. HGS, handgrip strength; RMW, respiratory muscle weakness; SMI, skeletal muscle mass index.
See this image and copyright information in PMC

References

    1. Global Initiative for Chronic Obstructive Lung Disease , “Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease (2024 Report)” (2023), https://goldcopd.org/2024‐gold‐report/.
    1. Marklund S., Bui K. L., and Nyberg A., “Measuring and Monitoring Skeletal Muscle Function in COPD: Current Perspectives,” International Journal of Chronic Obstructive Pulmonary Disease 14 (2019): 1825–1838. - PMC - PubMed
    1. Henrot P., Dupin I., Schilfarth P., et al., “Main Pathogenic Mechanisms and Recent Advances in COPD Peripheral Skeletal Muscle Wasting,” International Journal of Molecular Sciences 24 (2023): 6454. - PMC - PubMed
    1. Engelen M. P., Schols A. M., Baken W. C., Wesseling G. J., and Wouters E. F., “Nutritional Depletion in Relation to Respiratory and Peripheral Skeletal Muscle Function in Out‐Patients With COPD,” European Respiratory Journal 7 (1994): 1793–1797. - PubMed
    1. Ijiri N., Kanazawa H., Asai K., Watanabe T., and Hirata K., “Irisin, a Newly Discovered Myokine, Is a Novel Biomarker Associated With Physical Activity in Patients With Chronic Obstructive Pulmonary Disease,” Respirology 20 (2015): 612–617. - PubMed

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