Rachael A Evans1, Thomas E Dolmage2, Priscila G Robles3, Roger S Goldstein4, Dina Brooks3. 1. Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, England; Department of Medicine, University of Toronto, Toronto, ON, Canada. Electronic address: rachael.evans@uhl-tr.nhs.uk. 2. Department of Respiratory Diagnostic & Evaluation Services, West Park Healthcare Centre, Toronto, ON, Canada; Department of Respiratory Medicine, West Park Healthcare Centre, Toronto, ON, Canada. 3. Department of Respiratory Medicine, West Park Healthcare Centre, Toronto, ON, Canada; Department of Physical Therapy (Ms Robles, Dr Goldstein, and Prof Brooks), University of Toronto, Toronto, ON, Canada. 4. Department of Respiratory Medicine, West Park Healthcare Centre, Toronto, ON, Canada; Department of Respiratory Diagnostic & Evaluation Services, West Park Healthcare Centre, Toronto, ON, Canada; Department of Medicine, University of Toronto, Toronto, ON, Canada; Department of Physical Therapy (Ms Robles, Dr Goldstein, and Prof Brooks), University of Toronto, Toronto, ON, Canada.
Abstract
BACKGROUND: Cardiorespiratory fitness, assessed during cardiopulmonary exercise tests by peak oxygen uptake (Vo2pk), is an independent predictor of mortality in obesity. We investigated whether Vo2pk and systemic responses measured during field walking tests were similar to those measured during an incremental treadmill test (ITMT) in obese individuals with treated OSA. METHODS:Individuals with treated OSA and a BMI > 30 kg/m2 were recruited. Participants completed an ITMT, two 6-min walk tests (6MWTs), and two incremental shuttle walk tests (ISWTs) on three separate days in a randomized order. Expired gas analysis was performed during all tests. RESULTS: The study was completed by 16 patients (nine men) (mean [SD] age, 58 [12] y; BMI, 36.1 [7.6] kg/m2). There was no difference (P = .27) in Vo2pk assessed by the ITMT and the ISWT (2,266 [478] and 2,017 [561] mL/min, respectively). The Vo2pk measured by the 6MWT (1,778 [360] mL/min) was lower than that measured by the ITMT (P < .01). The limits of agreement for Vo2pk between the ISWT and the ITM were ± 730 mL/min. Cardiorespiratory responses during the ISWT and the ITMT reflected a graded response to a peak, whereas the 6MWT demonstrated a rapid rise to a plateau. CONCLUSIONS: The ISWT can be used instead of an ITMT and in preference to the 6MWT to assess cardiorespiratory fitness for a cohort of obese people with treated OSA. However, the imprecision of the agreement in Vo2pk between the ITMT and ISWT means they cannot be used interchangeably in an individual. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01930513; www.clinicaltrials.gov.
RCT Entities:
BACKGROUND:Cardiorespiratory fitness, assessed during cardiopulmonary exercise tests by peak oxygen uptake (Vo2pk), is an independent predictor of mortality in obesity. We investigated whether Vo2pk and systemic responses measured during field walking tests were similar to those measured during an incremental treadmill test (ITMT) in obese individuals with treated OSA. METHODS: Individuals with treated OSA and a BMI > 30 kg/m2 were recruited. Participants completed an ITMT, two 6-min walk tests (6MWTs), and two incremental shuttle walk tests (ISWTs) on three separate days in a randomized order. Expired gas analysis was performed during all tests. RESULTS: The study was completed by 16 patients (nine men) (mean [SD] age, 58 [12] y; BMI, 36.1 [7.6] kg/m2). There was no difference (P = .27) in Vo2pk assessed by the ITMT and the ISWT (2,266 [478] and 2,017 [561] mL/min, respectively). The Vo2pk measured by the 6MWT (1,778 [360] mL/min) was lower than that measured by the ITMT (P < .01). The limits of agreement for Vo2pk between the ISWT and the ITM were ± 730 mL/min. Cardiorespiratory responses during the ISWT and the ITMT reflected a graded response to a peak, whereas the 6MWT demonstrated a rapid rise to a plateau. CONCLUSIONS: The ISWT can be used instead of an ITMT and in preference to the 6MWT to assess cardiorespiratory fitness for a cohort of obese people with treated OSA. However, the imprecision of the agreement in Vo2pk between the ITMT and ISWT means they cannot be used interchangeably in an individual. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01930513; www.clinicaltrials.gov.
Authors: Rachael A Evans; Thomas E Dolmage; Priscila G Robles; Dina Brooks; Roger S Goldstein Journal: Chron Respir Dis Date: 2016-04-13 Impact factor: 2.444
Authors: S P Jürgensen; R Trimer; L Di Thommazo-Luporini; V Z Dourado; J C Bonjorno-Junior; C R Oliveira; R Arena; A Borghi-Silva Journal: Braz J Med Biol Res Date: 2016-07-11 Impact factor: 2.590