Original article
Inspiratory fraction as a marker of skeletal muscle dysfunction in patients with COPD
P. Cebolleroa, F. Zambom-Ferraresib, M. Hernándeza, J. Huetoa, J. Cascantea, M.M. Antonb,,
a Department of Pulmonary Medicine B, Complejo Hospitalario de Navarra, Spain
b Department of Health Sciences, Public University of Navarre, Spain
Received 18 April 2016, Accepted 21 July 2016
Abstract
Background

An inspiratory capacity to total lung capacity (IC/TLC) ratio of ≤25% has emerged as a better marker of mortality in chronic obstructive pulmonary disease (COPD) patients. The relationship among the IC/TLC ratio to lower extremity skeletal muscle function remains unknown.

Methods

Thirty-five men with moderate to severe COPD were divided into those with IC/TLC25% (n=16) and >25% (n=19). The subjects were tested for thigh muscle mass volume (MMT), maximal strength, power output of the lower extremities, and physical activity.

Results

Total MMT in the IC/TLC<25% group was significantly lower (413.91±89.42cm3) (p<0.001) than in the IC/TLC>25% group (575.20±11.76cm3). In the IC/TLC25% group, maximal strength of the lower extremities and muscle peak power output of the lower extremities were 36–56% lower (p<0.01) than among the patients in the IC/TLC>25% group.

Conclusion

IC/TLC25% is associated with reduced maximal strength and peak power output of the lower extremities. IC/TLC25% may have an important clinical relevance as an index to determine peripheral muscle dysfunction.

Keywords
Chronic obstructive pulmonary disease, Inspiratory fraction, Muscle mass, Muscle strength, Limb muscle dysfunction, Muscle power

Metrics

  • Impact Factor: 1.357(2015)
  • 5-years Impact Factor: 0,841
  • SCImago Journal Rank (SJR):0,29
  • Source Normalized Impact per Paper (SNIP):0,685