Introduction: Limb muscle wasting is one of main systemic manifestation of chronic obstructive pulmonary disease (COPD). However, the change of respiratory muscle is unclear.
Objectives: This study assessed the cross-sectional area (CSA) of the intercostal muscles (ICMs) in patients with COPD, using chest computed tomography (CT) and determined its association with the clinical characteristics of COPD.
Methods: They retrospectively reviewed 60 patients with stable COPD and compared them with 30 controls. CSA (mm2 ) of the ICM on chest CT was measured at the midline level of the lateral arch of the bilateral first rib with a 3-mm slice thickness by using CT histogram software. The association with the clinical characteristics of COPD and with the control groups was assessed.
Results: CSA of the ICM and the CSA/body mass index (BMI) were lower in the COPD group than in the control group. Patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 4 had a significantly lower CSA of the ICM than patients with stage 1, 2, and 3. CSA of the ICM was positively associated with FEV1 , %FEV1 predicted, FEV1 /FVC ratio, and BMI and negatively associated with age. However, there were no associations with PaO2 , PaCO2 , smoking status, 6-minute walk test, frequency of acute exacerbation of COPD, and serum C-reactive protein level.
Conclusion: Intercostal muscle atrophy occurs in COPD patients and is associated with severity of airway obstruction, BMI, and increasing age.
Keywords: COPD; computed tomography; cross sectional area; intercostal muscle.
© 2017 John Wiley & Sons Ltd.