RATIONALE: Although the major limitation to exercise performance in patients with COPD is dynamic hyperinflation, little is known about its relation to daily physical activity. OBJECTIVES: To analyze the contribution of dynamic hyperinflation, exercise tolerance, and airway oxidative stress to physical activity in patients with COPD. METHODS: In a cross-sectional study, we included 110 patients with moderate to very severe COPD. Daily physical activity was measured using a triaxial accelerometer providing a mean of 1-minute movement epochs as vector magnitude units (VMU). Patients performed the 6-minute walk test, incremental exercise test with measurement of breathing pattern and operating lung volumes, and constant-work rate test at 75% of maximal work rate. MEASUREMENTS AND MAIN RESULTS: Using the GOLD stage and BODE index, we determined arterial blood gases, lung volumes, diffusing capacity, and biomarkers in exhaled breath condensate. Daily physical activity was lower in the 89 patients who developed dynamic hyperinflation than in the 21 who did not (n =161 [SD 70] vs. n = 288 [SD 85] VMU; P = 0.001). Physical activity was mainly related to distance walked in 6 minutes (r = 0.72; P = 0.001), Vo(2) (r = 0.63; P = 0.001), change in end-expiratory lung volume during exercise (r = -0.73; P = 0.001), endurance time (r = 0.61; P = 0.001), and 8-isoprostane in exhaled breath condensate (r = -0.67; P = 0.001). In a multivariate linear regression analysis using VMU as a dependent variable, dynamic hyperinflation, change in end-expiratory lung volume, and distance walked in 6 minutes were retained in the prediction model (r(2) = 0.84; P = 0.001). CONCLUSIONS: Daily physical activity of patients with COPD is mainly associated with dynamic hyperinflation, regardless of severity classification.
RATIONALE: Although the major limitation to exercise performance in patients with COPD is dynamic hyperinflation, little is known about its relation to daily physical activity. OBJECTIVES: To analyze the contribution of dynamic hyperinflation, exercise tolerance, and airway oxidative stress to physical activity in patients with COPD. METHODS: In a cross-sectional study, we included 110 patients with moderate to very severe COPD. Daily physical activity was measured using a triaxial accelerometer providing a mean of 1-minute movement epochs as vector magnitude units (VMU). Patients performed the 6-minute walk test, incremental exercise test with measurement of breathing pattern and operating lung volumes, and constant-work rate test at 75% of maximal work rate. MEASUREMENTS AND MAIN RESULTS: Using the GOLD stage and BODE index, we determined arterial blood gases, lung volumes, diffusing capacity, and biomarkers in exhaled breath condensate. Daily physical activity was lower in the 89 patients who developed dynamic hyperinflation than in the 21 who did not (n =161 [SD 70] vs. n = 288 [SD 85] VMU; P = 0.001). Physical activity was mainly related to distance walked in 6 minutes (r = 0.72; P = 0.001), Vo(2) (r = 0.63; P = 0.001), change in end-expiratory lung volume during exercise (r = -0.73; P = 0.001), endurance time (r = 0.61; P = 0.001), and 8-isoprostane in exhaled breath condensate (r = -0.67; P = 0.001). In a multivariate linear regression analysis using VMU as a dependent variable, dynamic hyperinflation, change in end-expiratory lung volume, and distance walked in 6 minutes were retained in the prediction model (r(2) = 0.84; P = 0.001). CONCLUSIONS: Daily physical activity of patients with COPD is mainly associated with dynamic hyperinflation, regardless of severity classification.
Authors: David A Kaminsky; Kalpalatha K Guntupalli; Joan Lippmann; Stephanie M Burns; Melissa A Brock; Joan Skelly; Michael DeSarno; Heidi Pecott-Grimm; Ali Mohsin; Catherine LaRock-McMahon; Penney Warren; Martha C Whitney; Nicola A Hanania Journal: J Altern Complement Med Date: 2017-07-17 Impact factor: 2.579
Authors: Darwin Feliz-Rodriguez; Santiago Zudaire; Carlos Carpio; Elizabet Martínez; Antonia Gómez-Mendieta; Ana Santiago; Rodolfo Alvarez-Sala; Francisco García-Río Journal: Can Respir J Date: 2013 Sep-Oct Impact factor: 2.409
Authors: Christian M Lo Cascio; Mirja Quante; Eric A Hoffman; Alain G Bertoni; Carrie P Aaron; Joseph E Schwartz; Mark V Avdalovic; Vincent S Fan; Gina S Lovasi; Steven M Kawut; John H M Austin; Susan Redline; R Graham Barr Journal: Chest Date: 2016-12-06 Impact factor: 9.410
Authors: Eulogio Pleguezuelos; Cristina Esquinas; Eva Moreno; Lluis Guirao; Javier Ortiz; Joan Garcia-Alsina; Alex Merí; Marc Miravitlles Journal: Lung Date: 2016-01-07 Impact factor: 2.584