title: The dynamics of respiratory muscle changes during the progression of chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Pathological changes of the respiratory muscles (RM) during the development of chronic obstructive pulmonary disease (COPD) have not yet been studied in detail.
  
  
  OBJECTIVE
  The aim of the research was to assess RM status in COPD and the relationship between echodensitometric and morphological changes in the RM.
  
  
  METHODS
  The participants 152 male COPD patients were divided into three groups according to the severity of the disease: COPD₁ (mild), COPD₂ (moderate) and COPD₃ (severe). The status of the accessory RM in these groups was investigated using echodensitometry indices (echogenicity: IE; homogeneity: IH; and structural density: ISD) and the morphological material of the abdominal internal oblique muscle in 25 patients with COPD₁ and COPD₂.
  
  
  RESULTS
  Considerable differences among the COPD groups were revealed. In mild COPD a tendency toward increased homogeneity was detected (due to RM hypertrophy), while echogenicity results varied. IH and ISD decreased in moderate COPD, while IE was increased due to RM fatty infiltration and sclerosis (according to the morphological data). In severe COPD, IH and ISD rose again against a background of IE decrease. The presence of myolysis, sclerotic changes and contractures of myofibrils in the RM was significantly more frequently observed in COPD₁ and COPD₂ compared with the controls (where these features were rare). The sensitivity and specificity of the morphological and ultrasonic methods were similar in assessing atrophic and sclerotic RM changes, while their accuracy was lower in analyzing other morphological signs.
  
  
  CONCLUSIONS
  The echodensitometric parameters investigated reflect, in a complex way, different dynamics of degenerative RM processes during the progression of COPD.
authors: Department of Internal Medicine, Belarusian State Medical University, Minsk, Belarus.
authors: Aleksander E
authors: AE
authors: Makarevich
authors: Department of Internal Medicine, Belarusian State Medical University, Minsk, Belarus.
authors: Svetlana S
authors: SS
authors: Lemiasheuskaya
authors: Department of Internal Medicine, Belarusian State Medical University, Minsk, Belarus.
authors: Aleksander J
authors: AJ
authors: Poctavcev
authors: Department of General Surgery, Belarusian State Medical University, Minsk, Belarus.
authors: Aleksander I
authors: AI
authors: Lemeschewskij
authors: Department of Pathologic Anatomy, Belarusian State Medical University, Minsk, Belarus.
authors: Michail
authors: M
authors: Nedvedz
mesh_terms: D000368:Aged; D001706:Biopsy; D018450:Disease Progression; D006801:Humans; D006984:Hypertrophy; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D012132:Respiratory Muscles / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D012598:Sclerosis; D012720:Severity of Illness Index; D014463:Ultrasonography