title: Clinical importance of cross-sectional area of intercostal muscles in patients with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Limb muscle wasting is one of main systemic manifestation of chronic obstructive pulmonary disease (COPD). However, the change of respiratory muscle is unclear.
  
  
  OBJECTIVE
  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, %FEV1predicted, 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.
  
  
  CONCLUSIONS
  Intercostal muscle atrophy occurs in COPD patients and is associated with severity of airway obstruction, BMI, and increasing age.
authors.affiliation: Division Pulmonology and Allergy, Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Sunmi
authors.identifier: http://orcid.org/0000-0003-1474-1064
authors.initials: S
authors.lastname: Ju
authors.affiliation: Division Pulmonology and Allergy, Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Seung Jun
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Diagnostic Radiology, College of Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Mi Jung
authors.initials: MJ
authors.lastname: Park
authors.affiliation: Division Pulmonology and Allergy, Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Yu Ji
authors.initials: YJ
authors.lastname: Cho
authors.affiliation: Division Pulmonology and Allergy, Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Yi Yeong
authors.initials: YY
authors.lastname: Jeong
authors.affiliation: Department of Diagnostic Radiology, College of Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Kyung Nyeo
authors.initials: KN
authors.lastname: Jeon
authors.affiliation: Department of Diagnostic Radiology, College of Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Kyungsoo
authors.initials: K
authors.lastname: Bae
authors.affiliation: Division Pulmonology and Allergy, Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Jong Deog
authors.initials: JD
authors.lastname: Lee
authors.affiliation: Division Pulmonology and Allergy, Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Ho Cheol
authors.initials: HC
authors.lastname: Kim
mesh_terms: D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007366:Intercostal Muscles / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009133:Muscular Atrophy / Q000175:diagnosis / Q000209:etiology / Q000473:pathology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D056910:Republic of Korea / Q000453:epidemiology; D012129:Respiratory Function Tests / Q000379:methods; D012132:Respiratory Muscles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods; D000070857:Walk Test / Q000379:methods
chemical_list: D002097:C-Reactive Protein
keywords: COPD; computed tomography; cross sectional area; intercostal muscle