Validation of walking trails for the Urban Training of chronic obstructive pulmonary disease patients.

Purpose Accessible interventions to train patients with chronic obstructive pulmonary disease (COPD) are needed. We designed urban trails of different intensities (low, moderate and high) in different types of public spaces (boulevard, beach and park). We aimed to validate the trails' design by assessing the physiological response to unsupervised walking trails of: (1) different intensities in COPD patients, and (2) same intensity from different public spaces in healthy adults. Methods On different days and under standardized conditions, 10 COPD patients walked the three intensity trails designed in a boulevard space, and 10 healthy subjects walked the three intensity trails in three different spaces. We measured physiological response and energy expenditure using a gas analyzer. We compared outcomes across trails intensity and/or spaces using mixed-effects linear regression. Results In COPD patients, physiological response and energy expenditure increased significantly according to the trails intensity: mean (SD) peak O2 15.9 (3.5), 17.4 (4.7), and 17.7 (4.4) mL/min/kg (p-trend = 0.02), and MET-min 60 (23), 64 (26), 72 (31) (p-trend<0.01) in low, moderate and high intensity trails, respectively. In healthy subjects there were no differences in physiological response to walking trails of the same intensity across different spaces. Conclusions We validated the trails design for the training of COPD patients by showing that the physiological response to and energy expenditure on unsupervised walking these trails increased according to the predefined trails' intensity and did not change across trails of the same intensity in different public space. Walkable public spaces allow the design of trails that could be used for the training of COPD patients in the community

Heart Rate Recovery After 6-min Walking Test Predicts Acute Exacerbation in COPD

INTRODUCTION: Abnormalities of autonomic function have been reported in patients with chronic obstructive pulmonary disease (COPD). Our objectives were to identify determinants of abnormal heart rate recovery at 1 min (HRR1) following completion of the 6-min walk test (6MWT) in COPD and to establish whether abnormal HRR1 predicts acute exacerbations (AECOPD). METHODS: Hundred one COPD patients (FEV1 (SD) 53 (19) % predicted) were prospectively recruited in a multi-center study. HRR1 after the 6MWT was evaluated as the difference between heart rate at the end of the test and 1 min into the recovery (HRR1). Linear and logistic regression was used to identify predictors of HRR1 and AECOPD, respectively. The best HRR1 cut-off point to predict AECOPD was selected using the receiver operating characteristics (ROC) curves. The follow-up period was 12 months. RESULTS: Distance covered during the 6MWT (m) and DLco (% predicted) were independently associated with HRR1 (r 2 = 0.51, p = 0.001). Among several potential covariates, HRR1 emerged as the most significant predictor of AECOPD (Odds ratio [OR], 0.91 per beat of recovery; 95% confidence interval [CI], 0.85-0.97; p = 0.02). The ROC analysis indicated that subjects with HRR1 less than 14 beats (AUC, 0.71 [CI] 0.60-0.80; p = 0.0001) were more likely to suffer an exacerbation during the follow-up period (for HRR1, p = 0.004 [log-rank test]). CONCLUSIONS: HRR1 after the 6MWT is an independent predictor factor for AECOPD. Further studies are warranted to examine the physiological mechanisms associating a delayed HRR and acute exacerbations in COPD patients

Heart Rate Recovery After 6-min Walking Test Predicts Acute Exacerbation in COPD

INTRODUCTION: Abnormalities of autonomic function have been reported in patients with chronic obstructive pulmonary disease (COPD). Our objectives were to identify determinants of abnormal heart rate recovery at 1 min (HRR1) following completion of the 6-min walk test (6MWT) in COPD and to establish whether abnormal HRR1 predicts acute exacerbations (AECOPD). METHODS: Hundred one COPD patients (FEV1 (SD) 53 (19) % predicted) were prospectively recruited in a multi-center study. HRR1 after the 6MWT was evaluated as the difference between heart rate at the end of the test and 1 min into the recovery (HRR1). Linear and logistic regression was used to identify predictors of HRR1 and AECOPD, respectively. The best HRR1 cut-off point to predict AECOPD was selected using the receiver operating characteristics (ROC) curves. The follow-up period was 12 months. RESULTS: Distance covered during the 6MWT (m) and DLco (% predicted) were independently associated with HRR1 (r 2 = 0.51, p = 0.001). Among several potential covariates, HRR1 emerged as the most significant predictor of AECOPD (Odds ratio [OR], 0.91 per beat of recovery; 95% confidence interval [CI], 0.85-0.97; p = 0.02). The ROC analysis indicated that subjects with HRR1 less than 14 beats (AUC, 0.71 [CI] 0.60-0.80; p = 0.0001) were more likely to suffer an exacerbation during the follow-up period (for HRR1, p = 0.004 [log-rank test]). CONCLUSIONS: HRR1 after the 6MWT is an independent predictor factor for AECOPD. Further studies are warranted to examine the physiological mechanisms associating a delayed HRR and acute exacerbations in COPD patients

Real-world walking cadence in people with COPD

Introduction The clinical validity of real-world walking cadence in people with COPD is unsettled. Our objective was to assess the levels, variability and association with clinically relevant COPD characteristics and outcomes of real-world walking cadence. Methods We assessed walking cadence (steps per minute during walking bouts longer than 10 s) from 7days’ accelerometer data in 593 individuals with COPD from five European countries, and clinical and functional characteristics from validated questionnaires and standardised tests. Severe exacerbations during a 12-month follow-up were recorded from patient reports and medical registries. Results Participants were mostly male (80%) and had mean±SD age of 68±8 years, post-bronchodilator forced expiratory volume in 1 s (FEV1) of 57±19% predicted and walked 6880±3926 steps·day−1. Mean walking cadence was 88±9 steps·min−1, followed a normal distribution and was highly stable within-person (intraclass correlation coefficient 0.92, 95% CI 0.90–0.93). After adjusting for age, sex, height and number of walking bouts in fractional polynomial or linear regressions, walking cadence was positively associated with FEV1, 6-min walk distance, physical activity (steps·day−1, time in moderate-to-vigorous physical activity, vector magnitude units, walking time, intensity during locomotion), physical activity experience and health-related quality of life and negatively associated with breathlessness and depression (all p&lt;0.05). These associations remained after further adjustment for daily steps. In negative binomial regression adjusted for multiple confounders, walking cadence related to lower number of severe exacerbations during follow-up (incidence rate ratio 0.94 per step·min−1, 95% CI 0.91–0.99, p=0.009). Conclusions Higher real-world walking cadence is associated with better COPD status and lower severe exacerbations risk, which makes it attractive as a future prognostic marker and clinical outcome

Validation of Walking Trails for the Urban Training^TM of Chronic Obstructive Pulmonary Disease Patients

<div><p>Purpose</p><p>Accessible interventions to train patients with chronic obstructive pulmonary disease (COPD) are needed. We designed urban trails of different intensities (low, moderate and high) in different types of public spaces (boulevard, beach and park). We aimed to validate the trails’ design by assessing the physiological response to unsupervised walking trails of: (1) different intensities in COPD patients, and (2) same intensity from different public spaces in healthy adults.</p><p>Methods</p><p>On different days and under standardized conditions, 10 COPD patients walked the three intensity trails designed in a boulevard space, and 10 healthy subjects walked the three intensity trails in three different spaces. We measured physiological response and energy expenditure using a gas analyzer. We compared outcomes across trails intensity and/or spaces using mixed-effects linear regression.</p><p>Results</p><p>In COPD patients, physiological response and energy expenditure increased significantly according to the trails intensity: mean (SD) peak <math><mrow><mrow>V</mrow><mo>˙</mo></mrow></math>O₂ 15.9 (3.5), 17.4 (4.7), and 17.7 (4.4) mL/min/kg (p-trend = 0.02), and MET-min 60 (23), 64 (26), 72 (31) (p-trend<0.01) in low, moderate and high intensity trails, respectively. In healthy subjects there were no differences in physiological response to walking trails of the same intensity across different spaces.</p><p>Conclusions</p><p>We validated the trails design for the training of COPD patients by showing that the physiological response to and energy expenditure on unsupervised walking these trails increased according to the predefined trails’ intensity and did not change across trails of the same intensity in different public space. Walkable public spaces allow the design of trails that could be used for the training of COPD patients in the community.</p></div

Long-term efficacy and effectiveness of a behavioural and community-based exercise intervention (Urban Training) to increase physical activity in patients with COPD: a randomised controlled trial

There is a need to increase and maintain physical activity in patients with chronic obstructive pulmonary disease (COPD). We assessed 12-month efficacy and effectiveness of the Urban Training intervention on physical activity in COPD patients.This randomised controlled trial (NCT01897298) allocated 407 COPD patients from primary and hospital settings 1:1 to usual care (n=205) or Urban Training (n=202). Urban Training consisted of a baseline motivational interview, advice to walk on urban trails designed for COPD patients in outdoor public spaces and other optional components for feedback, motivation, information and support (pedometer, calendar, physical activity brochure, website, phone text messages, walking groups and a phone number). The primary outcome was 12-month change in steps·day-1 measured by accelerometer.Efficacy analysis (with per-protocol analysis set, n=233 classified as adherent to the assigned intervention) showed adjusted (95% CI) 12-month difference +957 (184-1731) steps·day-1 between Urban Training and usual care. Effectiveness analysis (with intention-to-treat analysis set, n=280 patients completing the study at 12 months including unwilling and self-reported non-adherent patients) showed no differences between groups. Leg muscle pain during walks was more frequently reported in Urban Training than usual care, without differences in any of the other adverse events.Urban Training, combining behavioural strategies with unsupervised outdoor walking, was efficacious in increasing physical activity after 12 months in COPD patients, with few safety concerns. However, it was ineffective in the full population including unwilling and self-reported non-adherent patients