Carlos Augusto Camillo

An official European Respiratory Society/American Thoracic Society technical standard: field walking tests in chronic respiratory disease

Field walking tests are commonly employed to evaluate exercise capacity, assess prognosis and evaluate treatment response in chronic respiratory diseases. In recent years, there has been a wealth of new literature pertinent to the conduct of the 6-min walk test (6MWT), and a growing evidence base describing the incremental and endurance shuttle walk tests (ISWT and ESWT, respectively). The aim of this document is to describe the standard operating procedures for the 6MWT, ISWT and ESWT, which can be consistently employed by clinicians and researchers. The Technical Standard was developed by a multidisciplinary and international group of clinicians and researchers with expertise in the application of field walking tests. The procedures are underpinned by a concurrent systematic review of literature relevant to measurement properties and test conduct in adults with chronic respiratory disease. Current data confirm that the 6MWT, ISWT and ESWT are valid, reliable and responsive to change with some interventions. However, results are sensitive to small changes in methodology. It is important that two tests are conducted for the 6MWT and ISWT. This Technical Standard for field walking tests reflects current evidence regarding procedures that should be used to achieve robust results. Technical Standard document: standard operating procedures for the 6MWT, ISWT and ESWT in chronic respiratory disease http://ow.ly/Bq2B9

An official systematic review of the European Respiratory Society/American Thoracic Society: measurement properties of field walking tests in chronic respiratory disease

This systematic review examined the measurement properties of the 6-min walk test (6MWT), incremental shuttle walk test (ISWT) and endurance shuttle walk test (ESWT) in adults with chronic respiratory disease. Studies that report the evaluation or use of the 6MWT, ISWT or ESWT were included. We searched electronic databases for studies published between January 2000 and September 2013. The 6-min walking distance (6MWD) is a reliable measure (intra-class correlation coefficients ranged from 0.82 to 0.99 in seven studies). There is a learning effect, with greater distance walked on the second test (pooled mean improvement of 26 m in 13 studies). Reliability was similar for ISWT and ESWT, with a learning effect also evident for ISWT (pooled mean improvement of 20 m in six studies). The 6MWD correlates more strongly with peak work capacity (r=0.59–0.93) and physical activity (r=0.40–0.85) than with respiratory function (r=0.10–0.59). Methodological factors affecting 6MWD include track length, encouragement, supplemental oxygen and walking aids. Supplemental oxygen also affects ISWT and ESWT performance. Responsiveness was moderate to high for all tests, with greater responsiveness to interventions that included exercise training. The findings of this review demonstrate that the 6MWT, ISWT and ESWT are robust tests of functional exercise capacity in adults with chronic respiratory disease. Systematic review: support for use of the 6MWT, ISWT and ESWT in adults with chronic respiratory disease http://ow.ly/Bq2Mz

Relationship between pulmonary function and physical activity in daily life in patients with COPD

BACKGROUND It remains unclear how closely the physical inactivity observed in patients with Chronic Obstructive Pulmonary Disease (COPD) relates to the severity of their airflow limitation. Furthermore, it is unknown whether spirometric variables such as maximal voluntary ventilation (MVV) and inspiratory capacity (IC) reflect the level of physical activity in daily life better than the forced expiratory volume in the first second (FEV(1)), the main spirometric variable used to determine the severity of COPD. The objective of the present study was to investigate the relationship between physical activity in daily life and the severity of COPD assessed by different spirometric variables: MVV, IC and FEV(1). METHODS Forty patients with COPD (21 men; 68+/-7 years; FEV(1) 41+/-14% predicted) were performed spirometry and assessment of the physical activity level in daily life using an accelerometer (SenseWear Armband). RESULTS MVV was significantly correlated to total energy expenditure per day, energy expenditure per day in activities demanding more than 3 metabolic equivalents (METs), number of steps per day and time spent per day in moderate and vigorous activities (0.42<or=r<or=0.52; p<0.01 for all). Correlation of these variables with IC and especially FEV(1) was more modest, borderline or not statistically significant. There was no difference in time spent in vigorous activities among patients classified according to the FEV(1)-based GOLD stages II, III and IV, differently than that observed when patients were classified in groups according to their MVV. CONCLUSION In COPD patients, MVV better reflects the physical activity level in daily life than FEV(1) and IC.

Step Counting and Energy Expenditure Estimation in Patients With Chronic Obstructive Pulmonary Disease and Healthy Elderly: Accuracy of 2 Motion Sensors

OBJECTIVE To compare the accuracy of 2 motion sensors (a pedometer and a multisensor) in terms of step counting and estimation of energy expenditure (EE) in patients with chronic obstructive pulmonary disease (COPD) and in healthy elderly. DESIGN In this descriptive study, all participants wore both motion sensors while performing a treadmill walking protocol at 3 different speeds corresponding to 30%, 60%, and 100% of the average speed achieved during a six-minute walk test. As criterion methods, EE was estimated by indirect calorimetry, and steps were registered by videotape. SETTING Research laboratory at a university hospital. PARTICIPANTS Patients with COPD (n=30; 17 men; mean age +/- SD, 67+/-8 y; mean forced expiratory volume in the first second [FEV(1)] predicted +/- SD, 46%+/-17%; mean body mass index [BMI] +/- SD, 24+/-4 kg.m(2)) and matched healthy elderly (n=30; 15 men; mean age +/- SD, 68+/-7 y; mean FEV(1) predicted +/- SD, 104%+/-21%; mean BMI +/- SD, 25+/-3 kg.m(2)). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURE Step counting and EE estimation during a treadmill walking protocol. RESULTS The pedometer was accurate for step counting and EE estimation in both patients with COPD and healthy elderly at the higher speed. However, it showed significant underestimation at the 2 slower speeds in both groups. The multisensor did not detect steps accurately at any speed, although it accurately estimated EE at all speeds in healthy elderly and at the intermediate and higher speeds in patients with COPD. CONCLUSIONS In both patients with COPD and healthy elderly, the multisensor showed better EE estimates during most walking speeds than the pedometer. Conversely, for step counting, accuracy is observed only with the pedometer during the higher walking speed in both groups.

Effects of 2 Exercise Training Programs on Physical Activity in Daily Life in Patients With COPD

BACKGROUND: The effects of different exercise training programs on the level of physical activity in daily life in patients with COPD remain to be investigated. OBJECTIVE: In patients with COPD we compared the effects of 2 exercise/training regimens (a high-intensity whole-body endurance-and-strength program, and a low-intensity calisthenics-and-breathing-exercises program) on physical activity in daily life, exercise capacity, muscle force, health-related quality of life, and functional status. METHODS: We randomized 40 patients with COPD to perform either endurance-and-strength training (no. = 20, mean ± SD FEV1 40 ± 13% of predicted) at 60–75% of maximum capacity, or calisthenics-and-breathing-exercises training (no. = 20, mean ± SD FEV1 39 ± 14% of predicted). Both groups underwent 3 sessions per week for 12 weeks. Before and after the training programs the patients underwent activity monitoring with motion sensors, incremental cycle-ergometry, 6-min walk test, and peripheral-muscle-force test, and responded to questionnaires on health-related quality of life and functional status (activities of daily living, pulmonary functional status, and dyspnea). RESULTS: Time spent active and energy expenditure in daily life were not significantly altered in either group. Exercise capacity and muscle force significantly improved only in the endurance-and-strength group. Health-related quality of life and functional status improved significantly in both groups. CONCLUSIONS: Neither training program significantly improved time spent active or energy expenditure in daily life. The training regimens similarly improved quality of life and functional status. Exercise capacity and muscle force significantly improved only in the high-intensity endurance-and-strength group.

The Minimal Important Difference in Physical Activity in Patients with COPD

Background Changes in physical activity (PA) are difficult to interpret because no framework of minimal important difference (MID) exists. We aimed to determine the minimal important difference (MID) in physical activity (PA) in patients with Chronic Obstructive Pulmonary Disease and to clinically validate this MID by evaluating its impact on time to first COPD-related hospitalization. Methods PA was objectively measured for one week in 74 patients before and after three months of rehabilitation (rehabilitation sample). In addition the intraclass correlation coefficient was measured in 30 patients (test-retest sample), by measuring PA for two consecutive weeks. Daily number of steps was chosen as outcome measurement. Different distribution and anchor based methods were chosen to calculate the MID. Time to first hospitalization due to an exacerbation was compared between patients exceeding the MID and those who did not. Results Calculation of the MID resulted in 599 (Standard Error of Measurement), 1029 (empirical rule effect size), 1072 (Cohens effect size) and 1131 (0.5SD) steps.day-1. An anchor based estimation could not be obtained because of the lack of a sufficiently related anchor. The time to the first hospital admission was significantly different between patients exceeding the MID and patients who did not, using the Standard Error of Measurement as cutoff. Conclusions The MID after pulmonary rehabilitation lies between 600 and 1100 steps.day-1. The clinical importance of this change is supported by a reduced risk for hospital admission in those patients with more than 600 steps improvement.

Effect of “add-on” interventions on exercise training in individuals with COPD: a systematic review

The aim of this review was to identify the effectiveness of therapies added on to conventional exercise training to maximise exercise capacity in patients with chronic obstructive pulmonary disease (COPD). Electronic databases were searched, identifying trials comparing exercise training with exercise training plus “add-on” therapy. Outcomes included peak oxygen uptake (V′O2peak), work rate and incremental/endurance cycle and field walking tests. Individual trial effects on exercise capacity were extracted and collated into eight subgroups and pooled for meta-analysis. Sensitivity analyses were conducted to explore the stability of effect estimates across studies employing patient-centred designs and those deemed to be of “high” quality (PEDro score >5 out of 10). 74 studies (2506 subjects) met review inclusion criteria. Interventions spanned a broad scope of clinical practice and were most commonly evaluated via the 6-min walking distance and V′O2peak. Meta-analysis revealed few clinically relevant and statistically significant benefits of “add-on” therapies on exercise performance compared with exercise training. Benefits favouring “add-on” therapies were observed across six different interventions (additional exercise training, noninvasive ventilation, bronchodilator therapy, growth hormone, vitamin D and nutritional supplementation). The sensitivity analyses included considerably fewer studies, but revealed minimal differences to the primary analysis. The lack of systematic benefits of “add-on” interventions is a probable reflection of methodological limitations, such as “one size fits all” eligibility criteria, that are inherent in many of the included studies of “add-on” therapies. Future clarification regarding the exact value of such therapies may only arise from adequately powered, multicentre clinical trials of tailored interventions for carefully selected COPD patient subgroups defined according to distinct clinical phenotypes. Add-on modalities show mostly minimal additional benefits to exercise capacity after conventional training in COPD http://ow.ly/XABi4

Moderate Intense Physical Activity Depends on Selected Metabolic Equivalent of Task (MET) Cut-Off and Type of Data Analysis

Background Accelerometry data are frequently analyzed without considering whether moderate-to-vigorous physical activities (MVPA) were performed in bouts of >10 minutes as defined in most physical activity guidelines. We aimed i) to quantify MVPA by using different commonly-applied physical activity guidelines, ii) to investigate the effect of bouts versus non-bouts analysis, and iii) to propose and validate a MVPA non-bouts cut-point to classify (in-) active subjects. Methods Healthy subjects (n=110;62±6yrs) and patients with Chronic Obstructive Pulmonary Disease (COPD) (n=113;62±5yrs) wore an activity monitor for 7 days. Three Metabolic Equivalent of Task (MET) cut-offs and one individual target (50% VO2 reserve) were used to define MVPA. First, all minutes of MVPA were summed up (NON-BOUTS). Secondly, only minutes performed in bouts of >10 minutes continuous activity were counted (BOUTS). Receiver operating characteristic (ROC) curve analyses were used to propose and (cross-) validate new MVPA non-bout cut-points based on the criterion of 30 minutes MVPA per day (BOUTS). Likelihood ratios (sensitivity/[1-specificity]) were used to express the association between the proposed MVPA non-bout target and the MVPA bout target of 30 min*day-1. Results MVPA was variable across physical activity guidelines with lowest values for age-specific cut-offs. Selecting a METs cut-point corresponding to 50% VO2 reserve revealed no differences in MVPA between groups. MVPA’s analyzed in BOUTS in healthy subjects were 2 to 4 fold lower than NON-BOUTS analyses and this was even 3 to 12 fold lower in COPD. The MVPA non-bouts cut-point of 80 min*day-1 using a 3 METs MVPA threshold delivered positive likelihood ratios of 5.1[1.5-19.6] (healthy subjects) and 2.3[1.6-3.3] (COPD). Conclusion MVPA varies upon the selected physical activity guideline/targets and bouts versus non-bouts analysis. Accelerometry measured MVPA non-bouts target of 80 min*day-1, using a 3 METs MVPA threshold, is associated to the commonly-used MVPA bout target of 30 min*day-1.

The Influence of Comorbidities on Outcomes of Pulmonary Rehabilitation Programs in Patients with COPD: A Systematic Review

Introduction. Chronic obstructive pulmonary disease (COPD) is associated with comorbidities such as cardiovascular disease, metabolic disease, osteoporosis, and anxiety and/or depression. Although pulmonary rehabilitation programs are proven to be beneficial in patients with COPD, it is unclear whether comorbidities influence pulmonary rehabilitation outcomes. The aim of the present review was to investigate to what extent the presence of comorbidities can affect pulmonary rehabilitation outcomes. Methods. The systematic literature search (Pubmed, EMBASE, and PEDro) resulted in 4 articles meeting the inclusion criteria. The odds ratios (95% confidence intervals) of the logistic regression analyses, with comorbidities as independent variables and pulmonary rehabilitation outcomes (dyspnea, functional exercise capacity, and quality of life) as dependent variables, were used for data extraction. Results. Patients with anxiety and/or depression less likely improve in dyspnea. Osteoporosis is associated with less improvements in functional exercise capacity, while cardiovascular disease does not seem to negatively impact on this outcome. Patients with cardiovascular comorbidity will experience less positive changes in quality of life. Conclusion. Evidence from literature suggests that comorbidities can have a negative influence on pulmonary rehabilitation outcomes. Screening for comorbidities in pulmonary rehabilitation settings seems useful to readdress the right patients for individually tailored pulmonary rehabilitation.

Evaluation of a New Motion Sensor in Patients With Chronic Obstructive Pulmonary Disease

OBJECTIVE To assess the criterion validity and reproducibility of a new pedometer in patients with chronic obstructive pulmonary disease (COPD). DESIGN Cross-sectional study. SETTING Outpatient physiotherapy clinic from a university hospital. PARTICIPANTS Patients with COPD (N=30; 17 men; forced expiratory volume in the first second, 44±17% predicted) were videotaped while performing 2 protocols: one including 2 slow and 2 fast 5-minute walks, and another including a circuit of activities of daily living (ADLs). Concomitantly, patients wore 2 motion sensors: the new pedometer and a multisensor accelerometer. INTERVENTIONS None. MAIN OUTCOME MEASURES Step counting (SC), energy expenditure (EE), walking distance (WD), activity time (AT), and walking intensity (WI) registered by the pedometer were compared with video and the multisensor as criterion methods. RESULTS Correlations between the pedometer and the criterion method were high for SC during slow and fast walking (r=.79 and r=.95) and for EE during fast walking (r=.83). Correlation was more modest for EE during slow walking (r=.65) and for WD and WI during both speeds (.47<r<.68). The agreement between methods was also good, according to Bland-Altman plots. The device was reproducible for registering SC, WD, and EE during slow walking and for all variables during fast walking (intraclass correlation coefficient >.79 for all). During the ADLs circuit, the pedometer underestimated AT by an average of 55% but provided an acceptable EE estimation in a group basis (average difference of 6% with the multisensor). CONCLUSIONS In patients with COPD, the new pedometer analyzed in the present study is reproducible for most outcomes and highly valid for SC during slow and fast walking and EE during fast walking. The devices validity is more limited for EE during slow walking, and WD and WI at both speeds. Furthermore, during the performance of ADLs, it significantly underestimates activity time but provides an acceptable estimation of EE in a group basis.