Background:

Dysphagia is frequently observed in subjects with chronic obstructive pulmonary disease (COPD). But tongue strength has not been investigated yet in COPD subjects. The investigators hypothesized that tongue strength is weaker in COPD subjects compared to normal subjects.

Methods:

This was a single-centre, observational, and cross-sectional study. Twenty-seven subjects with COPD and twenty-four age-matched control subjects were enrolled in this study. Isometric tongue strength was measured using a device fitted with a disposable oral balloon probe. The investigators also evaluated handgrip strength, gait speed, and appendicular skeletal muscle mass (ASM) to define participants as having sarcopenia. ASM, fat free mass index (FFMI), and skeletal muscle mass index (SMI) were measured by bioelectrical impedance analysis. Gait speed was measured using the 6-meter walking test. The eating assessment test-10 (EAT-10) was used to diagnose dysphagia.

Inclusion Criteria:

• Clinical diagnosis of stable COPD.
• Age-matched control subjects who did not have any pulmonary disease.

Exclusion Criteria:

• Participants with metallic implants.
• History of stroke disease.
• History of neuromuscular disease.
• Participants who did not have their front teeth.

COPD subjects were chosen from a group of subjects who had visited the Department of Respiratory Medicine and Allergology at Kindai University Hospital from December 2019 to May 2020.