title: Validity of physical activity monitors during daily life in patients with COPD.
abstract: Symptoms during physical activity and physical inactivity are hallmarks of chronic obstructive pulmonary disease (COPD). Our aim was to evaluate the validity and usability of six activity monitors in patients with COPD against the doubly labelled water (DLW) indirect calorimetry method. 80 COPD patients (mean ± sd age 68 ± 6 years and forced expiratory volume in 1 s 57 ± 19% predicted) recruited in four centres each wore simultaneously three or four out of six commercially available monitors validated in chronic conditions for 14 consecutive days. A priori validity criteria were defined. These included the ability to explain total energy expenditure (TEE) variance through multiple regression analysis, using TEE as the dependent variable with total body water (TBW) plus several physical activity monitor outputs as independent variables; and correlation with activity energy expenditure (AEE) measured by DLW. The Actigraph GT3X (Actigraph LLC, Pensacola, FL, USA), and DynaPort MoveMonitor (McRoberts BV, The Hague, the Netherlands) best explained the majority of the TEE variance not explained by TBW (53% and 70%, respectively) and showed the most significant correlations with AEE (r=0.71, p<0.001 and r=0.70, p<0.0001, respectively). The results of this study should guide users in choosing valid activity monitors for research or for clinical use in patients with chronic diseases such as COPD.
authors: Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh.
authors: Roberto A
authors: RA
authors: Rabinovich
authors: Zafeiris
authors: Z
authors: Louvaris
authors: Yogini
authors: Y
authors: Raste
authors: Daniel
authors: D
authors: Langer
authors: Hans
authors: H
authors: Van Remoortel
authors: Santiago
authors: S
authors: Giavedoni
authors: Chris
authors: C
authors: Burtin
authors: Eloisa M G
authors: EM
authors: Regueiro
authors: Ioannis
authors: I
authors: Vogiatzis
authors: Nicholas S
authors: NS
authors: Hopkinson
authors: Michael I
authors: MI
authors: Polkey
authors: Frederick J
authors: FJ
authors: Wilson
authors: William
authors: W
authors: Macnee
authors: Klaas R
authors: KR
authors: Westerterp
authors: Thierry
authors: T
authors: Troosters
mesh_terms: D056044:Actigraphy; D000203:Activities of Daily Living; D000368:Aged; D000886:Anthropometry; D001834:Body Water; D002153:Calorimetry, Indirect / Q000295:instrumentation; D003430:Cross-Sectional Studies; D004734:Energy Metabolism; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D009043:Motor Activity; D010101:Oxygen Consumption; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D012044:Regression Analysis; D011795:Surveys and Questionnaires