INFLUENCE OF DIAPHRAGM DYSFUNCTION, EXERCISE CAPACITY, AND NUTRITION ON DYSPNEA SEVERITY OF COPD PATIENTS

TYPE: Abstract Publication TOPIC: Respiratory Care PURPOSE: Dyspnea is one of the disabling symptoms among COPD patients. The diaphragm is a major muscle of inspiration, and is supposed to play a crucial role in symptoms pathogenesis. The aim of this study was to evaluate the relationship of dyspnea with diaphragm function, exercise capacity, respiratory function, body composition and nutritional status. METHODS: Forty-six COPD patients were stratified into two groups according to dyspnea, using modified Medical Research Council Questionnaire (mMRC) as mild (Group-1, mMRC<2) and moderate-severe)(Group-2, mMRC ≥ 2). Patients underwent COPD Assessment Test (CAT), spirometry, bioelectrical impedance analysis, diaphragm ultrasonography [(USG) expressed as right diaphragm thickening fraction (end-expiration /end-inspiration thickness ratio)], exercise capacity tests [4-meter gait speed (4MGS) and 6-min walking distance (6MWD)]. nutritional status [Mini Nutritional Assessment (MNA) ], health-related quality of life [St. George Respiratory Questionnaire (SGRQ)]. RESULTS: The characteristics of patients according to dyspnea severity are given in the Table. Group-2 patients had higher prevalence of men and of past smokers, higher CAT, lower FEV1/VC , decreased exercise capacity (i.e. 4MGS p=0.017, and 6MWD , p=0.002), worse MNA (P=0.046) and SGRQ (P=0.001), more respiratory exacerbations (p=0,011) and lower right diaphragm thickening fraction (P=0.011). Multivariate analysis confirmed the association of dyspnea severity with decreased diaphragm thickening fraction (p = 0.044). CONCLUSIONS: These findings confirm that diaphragm dysfunction plays an important role in dyspnea pathogenesis of COPD patients. The evaluation of diaphragm performance together with exercise capacity and nutritional status is important in the multidisciplinary approach and management of COPD. CLINICAL IMPLICATIONS: Not applicable DISCLOSURE: No significant relationships. KEYWORDS: nutritional status, diaphragmatic function, dyspnea