Annemarie Lee

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

Updating the minimal important difference for six-minute walk distance in patients with chronic obstructive pulmonary disease.

OBJECTIVE To establish the minimal important difference (MID) for the six-minute walk distance (6MWD) in persons with chronic obstructive pulmonary disease (COPD). DESIGN Analysis of data from an observational study using distribution- and anchor-based methods to determine the MID in 6MWD. SETTING Outpatient pulmonary rehabilitation program at 2 teaching hospitals. PARTICIPANTS Seventy-five patients with COPD (44 men) in a stable clinical state with mean age 70 years (SD 9 y), forced expiratory volume in one second 52% (SD 21%) predicted and baseline walking distance 359 meters (SD 104 m). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Participants completed the six-minute walk test before and after a 7-week pulmonary rehabilitation program. Participants and clinicians completed a global rating of change score while blinded to the change in 6MWD. RESULTS The mean change in 6MWD in participants who reported themselves to be unchanged was 17.7 meters, compared with 60.2 meters in those who reported small change and 78.4 meters in those who reported substantial change (P=.004). Anchor-based methods identified an MID of 25 meters (95% confidence interval 20-61 m). There was excellent agreement with distribution-based methods (25.5-26.5m, kappa=.95). A change in 6MWD of 14% compared with baseline also represented a clinically important effect; this threshold was less sensitive than for absolute change (sensitivity .70 vs .85). CONCLUSIONS The MID for 6MWD in COPD is 25 meters. Absolute change in 6MWD is a more sensitive indicator than percentage change from baseline. These data support the use of 6MWD as a patient-important outcome in research and clinical practice.

The six-minute walk test: a useful metric for the cardiopulmonary patient

Measurement of exercise capacity is an integral element in assessment of patients with cardiopulmonary disease. The 6‐min walk test (6MWT) provides information regarding functional capacity, response to therapy and prognosis across a range of chronic cardiopulmonary conditions. A distance less than 350 m is associated with increased mortality in chronic obstructive pulmonary disease, chronic heart failure and pulmonary arterial hypertension. Desaturation during a 6MWT is an important prognostic indicator for patients with interstitial lung disease. The 6MWT is sensitive to commonly used therapies in chronic obstructive pulmonary disease such as pulmonary rehabilitation, oxygen, long‐term use of inhaled corticosteroids and lung volume reduction surgery. However, it appears less reliable to detect changes in clinical status associated with medical therapies for heart failure. A change in walking distance of more than 50 m is clinically significant in most disease states. When interpreting the results of a 6MWT, consideration should be given to choice of predictive values and the methods by which the test was carried out.

What prevents people with chronic obstructive pulmonary disease from attending pulmonary rehabilitation? A systematic review.

Pulmonary rehabilitation is an essential component of care for people with chronic obstructive pulmonary disease (COPD) and is supported by strong scientific evidence. Despite this, many people with COPD do not complete their program or choose not to attend at all. The aim of this study was to determine the factors associated with uptake and completion of pulmonary rehabilitation for people with COPD. Seven electronic databases were searched for qualitative or quantitative studies that documented factors associated with uptake and completion of pulmonary rehabilitation in people with COPD. Two reviewers independently extracted data, which was synthesized to provide overall themes. Travel and transport were consistently identified as barriers to both uptake and completion. A lack of perceived benefit of pulmonary rehabilitation also influenced both uptake and completion. The only demographic features that consistently predicted non-completion were being a current smoker (pooled odds ratio 0.17, 95% confidence interval 0.10 to 0.32) and depression. The limited data available regarding barriers to uptake indicated that disruption to usual routine, influence of the referring doctor and program timing were important. In conclusion poor access to transport and lack of perceived benefit affect uptake of pulmonary rehabilitation. Current smokers and patients who are depressed are at increased risk of non-completion. Enhancing attendance in pulmonary rehabilitation will require more attention to transportation, support for those at risk of non-completion and greater involvement of patients in informed decisions about their care.

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

Lack of perceived benefit and inadequate transport influence uptake and completion of pulmonary rehabilitation in people with chronic obstructive pulmonary disease: a qualitative study

QUESTION What prevents people with chronic obstructive pulmonary disease (COPD) from attending and completing pulmonary rehabilitation programs? DESIGN Qualitative design using semi-structured interviews. PARTICIPANTS 19 adults with COPD who had declined to participate and 18 adults with COPD who had not completed a pulmonary rehabilitation program at a metropolitan teaching hospital. RESULTS A lack of perceived benefit from pulmonary rehabilitation was a significant theme for those who chose not to participate in pulmonary rehabilitation. Participants expressed perceptions that exercise was not a worthwhile treatment, or that they were already doing enough exercise at home. Difficulty getting to the program related to poor mobility, lack of transport, and cost of travel was a significant theme, expressed both by those who chose not to participate and those who did not complete. Another major theme associated with both uptake and completion involved being unwell, with participants indicating that the burden of COPD and other comorbidities impacted on attendance. Minor themes involved competing demands on time, older age, fatigue, program timing, and lack of social support. CONCLUSION Many people with COPD who elect not to take up a referral to pulmonary rehabilitation perceive that they would not experience any health benefits from attendance. Difficulties with travel to the program and being unwell are barriers to both uptake and completion. Improving attendance at pulmonary rehabilitation requires consideration of how information regarding the proven benefits of pulmonary rehabilitation can be conveyed to eligible patients, along with flexible program models that facilitate access and accommodate co-morbid disease.

Home-based rehabilitation for COPD using minimal resources: a randomised, controlled equivalence trial

Background Pulmonary rehabilitation is a cornerstone of care for COPD but uptake of traditional centre-based programmes is poor. We assessed whether home-based pulmonary rehabilitation, delivered using minimal resources, had equivalent outcomes to centre-based pulmonary rehabilitation. Methods A randomised controlled equivalence trial with 12 months follow-up. Participants with stable COPD were randomly assigned to receive 8 weeks of pulmonary rehabilitation by either the standard outpatient centre-based model, or a new home-based model including one home visit and seven once-weekly telephone calls from a physiotherapist. The primary outcome was change in 6 min walk distance (6MWD). Results We enrolled 166 participants to receive centre-based rehabilitation (n=86) or home-based rehabilitation (n=80). Intention-to-treat analysis confirmed non-inferiority of home-based rehabilitation for 6MWD at end-rehabilitation and the confidence interval (CI) did not rule out superiority (mean difference favouring home group 18.6 m, 95% CI −3.3 to 40.7). At 12 months the CI did not exclude inferiority (−5.1 m, −29.2 to 18.9). Between-group differences for dyspnoea-related quality of life did not rule out superiority of home-based rehabilitation at programme completion (1.6 points, −0.3 to 3.5) and groups were equivalent at 12 months (0.05 points, −2.0 to 2.1). The per-protocol analysis showed the same pattern of findings. Neither group maintained postrehabilitation gains at 12 months. Conclusions This home-based pulmonary rehabilitation model, delivered with minimal resources, produced short-term clinical outcomes that were equivalent to centre-based pulmonary rehabilitation. Neither model was effective in maintaining gains at 12 months. Home-based pulmonary rehabilitation could be considered for people with COPD who cannot access centre-based pulmonary rehabilitation. Trial registration number NCT01423227, clinicaltrials.gov.

Effects of pulmonary rehabilitation in bronchiectasis: A retrospective study

There is limited information about the benefits of pulmonary rehabilitation (PR) in patients with bronchiectasis. This study aimed to evaluate the effects of an out-patient PR program in patients with a primary diagnosis of bronchiectasis and to compare them with a matched COPD group who completed the same PR program. A retrospective review was conducted of patients with bronchiectasis or COPD who completed 6 to 8 weeks of PR at two tertiary institutions. The outcome measures were the 6-minute walk distance (6MWD) and Chronic Respiratory Disease Questionnaire (CRQ). Ninety-five patients with bronchiectasis completed the PR (48 male; FEV1 63 [24] % predicted; age 67 [10] years). Significant improvements in 6MWD (mean change 53.4 m, 95% CI 45.0 to 61.7) and CRQ total score (mean change 14.0 units, 95% CI 11.3 to 16.7) were observed immediately following PR. In patients with complete follow-up (n = 37), these improvements remained significantly higher than baseline at 12 months (20.5 m, 95% CI 1.4 to 39.5 for 6MWD; 12.1 points, 95% CI 5.7 to 18.4 for CRQ total score). The time trend and changes in the 6MWD and CRQ scores were not significantly different between the bronchiectasis and the COPD groups (all p > 0.05). This study supports the inclusion of patients with bronchiectasis in existing PR programs. Further prospective RCTs are warranted to substantiate these findings.

Clinical determinants of the 6-Minute Walk Test in bronchiectasis

BACKGROUND The 6-Minute Walk Test (6MWT) is a widely used measurement of functional exercise capacity in chronic lung disease. While exercise intolerance has been identified in patients with bronchiectasis, the clinical determinants of the 6MWT in this population have not been examined. The aim of this study was to 1) establish the relationship between the 6-Minute Walk Distance (6MWD), disease severity and Health-Related Quality of Life (HRQOL) and 2) identify predictors of exercise tolerance in adults with bronchiectasis. METHODS The 6MWT was performed in 27 patients with bronchiectasis (mean [SD] FEV(1) 73.9% predicted [23.4]). Disease severity was assessed using spirometry and HRCT scoring while HRQOL was evaluated using the St Georges Respiratory Questionnaire (SGRQ) and the Short-Form 36 (SF-36). The relationships were evaluated using correlation and multiple regression. RESULTS The 6MWD correlated positively with FVC (r=0.52, p<0.01), generations of bronchopulmonary divisions (r(s)=0.38, p<0.05) and SF-36 physical summary (r=0.71, p<0.001) while a negative correlation was observed between all domains of the SGRQ (all correlations r>0.5, p<0.001). Multiple regression analysis indicated that the SGRQ activity, symptom scores and generations of bronchial divisions involved were identified as independent predictors of the 6MWD, explaining 76% of the variance. CONCLUSIONS Measures of HRQOL demonstrated a stronger association with the 6MWD compared to physiological measures of disease severity in patients with predominantly mild to moderate bronchiectasis.

Benefits and costs of home-based pulmonary rehabilitation in chronic obstructive pulmonary disease - a multi-centre randomised controlled equivalence trial

BackgroundPulmonary rehabilitation is widely advocated for people with chronic obstructive pulmonary disease (COPD) to improve exercise capacity, symptoms and quality of life, however only a minority of individuals with COPD are able to participate. Travel and transport are frequently cited as barriers to uptake of centre-based programs. Other models of pulmonary rehabilitation, including home-based programs, have been proposed in order to improve access to this important treatment. Previous studies of home-based pulmonary rehabilitation in COPD have demonstrated improvement in exercise capacity and quality of life, but not all elements of the program were conducted in the home environment. It is uncertain whether a pulmonary rehabilitation program delivered in its entirety at home is cost effective and equally capable of producing benefits in exercise capacity, symptoms and quality of life as a hospital-based program. The aim of this study is to compare the costs and benefits of home-based and hospital-based pulmonary rehabilitation for people with COPD.Methods/DesignThis randomised, controlled, equivalence trial conducted at two centres will recruit 166 individuals with spirometrically confirmed COPD. Participants will be randomly allocated to hospital-based or home-based pulmonary rehabilitation. Hospital programs will follow the traditional outpatient model consisting of twice weekly supervised exercise training and education for eight weeks. Home-based programs will involve one home visit followed by seven weekly telephone calls, using a motivational interviewing approach to enhance exercise participation and facilitate self management. The primary outcome is change in 6-minute walk distance immediately following intervention. Measurements of exercise capacity, physical activity, symptoms and quality of life will be taken at baseline, immediately following the intervention and at 12 months, by a blinded assessor. Completion rates will be compared between programs. Direct healthcare costs and indirect (patient-related) costs will be measured to compare the cost-effectiveness of each program.DiscussionThis trial will identify whether home-based pulmonary rehabilitation can deliver equivalent benefits to centre-based pulmonary rehabilitation in a cost effective manner. The results of this study will contribute new knowledge regarding alternative models of pulmonary rehabilitation and will inform pulmonary rehabilitation guidelines for COPD.Trial registrationClinicalTrials.gov: NCT01423227.