Field Walking Tests Are Reliable and Responsive to Exercise Training in People With Non–Cystic Fibrosis Bronchiectasis

Clinical determinants of the modified incremental step test in adults with non-cystic fibrosis bronchiectasis

OBJECTIVES

This study primarily aimed to investigate the clinical determinants of the Modified Incremental Step Test (MIST) in adults with non-cystic fibrosis bronchiectasis (NCFB). A secondary objective was to compare the cardiopulmonary responses after the MIST and Incremental Shuttle Walk Test (ISWT), two commonly adopted symptom-limited maximum field tests in chronic respiratory diseases.

METHODS

Forty-six patients with clinically stable bronchiectasis participated in this cross-sectional study. MIST and ISWT were performed to determine exercise capacity, while disease severity, fatigue, and quality of life were assessed using the Bronchiectasis Severity Index (BSI), the Fatigue Severity Scale (FSS), and St. George's Respiratory Questionnaire (SGRQ), respectively. Quadriceps muscle strength was evaluated using a hand-held dynamometer, walking speed with a wireless inertial sensing device, and the level of physical activity (steps/day) with a pedometer.

RESULTS

The BSI score, quadriceps muscle strength, daily step count, and the SGRQ total score explained 61.9% of the variance in the MIST (p < 0.001, R2 = 0.67, AR2 = 0.619). The BSI score (r = -0.412, p = 0.004), quadriceps muscle strength (r = 0.574, p = 0.001), daily step count (r = 0.523, p < 0.001), walking speed (r = 0.402, p = 0.006), FSS score (r = -0.551, p < 0.001), and SGRQ total score (r = -0.570, p < 0.001) correlated with the MIST. The patients achieved higher heart rates (HR), HR%, desaturation, dyspnea, and leg fatigue in the MIST compared to the ISWT (p < 0.05).

CONCLUSIONS

Disease severity, quadriceps muscle strength, physical activity level, and quality of life were determinants of MIST. The advantages of the MIST, including higher cardiopulmonary response than ISWT and greater portability, which facilitates its use in various settings, make MIST the preferred choice for investigating symptom-limited exercise capacity in patients with NCFB.

Reliability and validity of the incremental shuttle walk test in patients with fully ambulatory multiple sclerosis

BACKGROUND

Functional exercise capacity evaluation is crucial to monitor treatment effects and disease progression in people with multiple sclerosis (pwMS). Compared to other tests, the incremental shuttle walking test (ISWT), which more accurately reflects cardiovascular responses, may be more useful for assessing exercise capacity. The aim of the study is to investigate the reliability and validity of the ISWT.

METHODS

Thirty-six pwMS with an Expanded Disability Status Scale (EDSS) score<4.5 between the ages of 25 and 65 were included in the study. The subjects underwent practice (ISWT-p) before undergoing the test-retest protocol in order to rule out the ISWT learning effect (ISWT-1 - ISWT-2). ISWT-1 and ISWT-2 were administered with a 3-7 day interval for test-retest reliability. Six-minutes walking test (6MWT) were applied for concurrent validity. The EDSS, pulmonary function tests, Fatigue Impact Scale (FIS), respiratory muscle strength [maximum inspiratory and expiratory pressure (MIP-MEP)] measurements were made for convergent validity.

RESULTS

ISWT was found to have excellent test-retest reliability with an ICC value of 0.97. The area under the curve value was 0.904 indicating that ISWT has a good performance for predicting disease severity. The moderate correlation between ISWT and 6MWT (rho: 0.68, p<0,001) proved concurrent validity. It was also moderately correlated with EDSS, MEP (rho: -0.58 and 0.47 respectively), weakly correlated with MIP and FIS (rho:0.37 and -0.36, respectively) while not correlated with pulmonary function tests.

CONCLUSION

The ISWT had excellent test-retest reliability, acceptable criterion and construct validity in ambulatory MS patients.

Exercise Capacity and Physical Activity in Non-Cystic Fibrosis Bronchiectasis after a Pulmonary Rehabilitation Home-Based Programme: A Randomised Controlled Trial

BACKGROUND

Patients with chronic respiratory disease have low exercise capacity and limited physical activity (PA), which is associated with worsening dyspnoea, exacerbations, and quality of life. The literature regarding patients with non-cystic fibrosis bronchiectasis (non-CF BQ) is scarce, especially regarding the use of cardiopulmonary exercise tests (CPET) to assess the effects of home-based pulmonary rehabilitation programmes (HPRP). The aim was to evaluate the effect of an HPRP on the exercise capacity of non-CF BQ patients using CPET and PA using an accelerometer.

METHODS

Our study describes a non-pharmacological clinical trial in non-CF BQ patients at the Virgen Macarena University Hospital (Seville, Spain). The patients were randomised into two groups: a control group (CG), which received general advice on PA and educational measures, and the intervention group (IG), which received a specific 8-week HPRP with two hospital sessions. The variables included were those collected in the CPET, the accelerometer, and others such as a 6 min walking test (6MWT) and dyspnoea. The data were collected at baseline and at an 8-week follow-up.

RESULTS

After the intervention, there was a significant increase in peak VO₂ in the IG, which was not evidenced in the GC (IG 66.8 ± 15.5 mL/min p = 0.001 vs. CG 62.2 ± 14.14 mL/min, p = 0.30). As well, dyspnoea according to the mMRC (modified Medical Research Council), improved significantly in IG (2.19 ± 0.57 to 1.72 ± 0.05, p = 0.047) vs. CG (2.07 ± 0.7 to 2.13 ± 0.64, p = 0.36). In addition, differences between the groups in walked distance (IG 451.19 ± 67.99 m, p = 0.001 vs. CG 433.13 ± 75.88 m, p = 0.981) and in physical activity (IG 6591 ± 3482 steps, p = 0.007 vs. CG 4824 ± 3113 steps, p = 0.943) were found.

CONCLUSION

Participation in a specific HPRP improves exercise capacity, dyspnoea, walked distance, and PA in non-CF BQ patients.

Video game-based exercise in children and adolescents with non-cystic fibrosis bronchiectasis: A randomized comparative study of aerobic and breathing exercises

BACKGROUND

Video game-based systems have been proposed to improve effectiveness and compliance with exercise training in children and adolescents with noncystic fibrosis bronchiectasis (NCFB). This study aimed to investigate the effects of aerobic and breathing video game-based exercises (VGE) on pulmonary function, respiratory and peripheral muscle strength, functional capacity, and balance in children and adolescents with NCFB.

METHOD

Thirty-nine children and adolescents aged between 8 and 18 years with NCFB were randomly allocated into three groups as "home-based chest physiotherapy group" (CP), "aerobic VGE given in addition to home-based chest physiotherapy group" (CP + aerobic VGE), and "breathing VGE given in addition to home-based chest physiotherapy group" (CP + breathing VGE). All three groups performed chest physiotherapy program twice a day for 7 days per week for 8 weeks. Pulmonary function, respiratory and peripheral muscle strength, functional capacity, and balance were assessed at baseline and after 8 weeks of training.

RESULTS

The improvement in maximum expiratory pressure and balance scores were significantly higher in both CP + aerobic and CP + breathing VGE groups. The significant improvement in maximum inspiratory pressure was greater in the CP + breathing VGE group. The changes in peripheral muscle strength and functional capacity were significantly higher in the CP + aerobic VGE group.

CONCLUSIONS

The present study showed that aerobic VGE provides additional benefits in improving peripheral muscle strength and functional capacity, while breathing VGE provides further increase in improving respiratory muscle strength. In addition, both aerobic and breathing VGE were effective in improving balance, but they were not superior to each other.

Repeatability of the 6-min walk test in non-cystic fibrosis bronchiectasis

Non-cystic fibrosis bronchiectasis (NCFB) is a chronic lung disease characterized by progressive and irreversible changes of the bronchial tree. The evaluation of exercise capacity is essential to manage this disease. This study aims to determine the within-subject repeatability of two Six Minute Walk Test (6MWT) in adults with NCFB. NCFB. This cross-sectional observational study included 66 NCFB subjects above 18 years-old (mean of 55 ± 17 years old, 68% women). 73% of the participants presented moderate to severe clinical condition classified by Bronchiectasis Severity Index. It showed that these participants walked 16.6 m less (95%CI 3.8 to 29.4; p < 0.01) in the second 6MWT when compared to the first test, with a within-subject coefficient variation of 9.4% (95%CI 7.2-11.2%) and an intra-test reliability with a high intraclass correlation coefficient of 0.88 (95%CI 0.80-0.93). Bland-Altman plot showed an agreement regarding test repeatability, besides presented a large limit of agreement (- 85 to 116 m). Respiratory rate and systolic blood pressure were significantly higher before starting the second test. In conclusion, 6MWT seems to be reproducible in NCFB subjects and vital sign verification should be attentively checked to assess if the patient is fully recovered to perform a second test, as well as the disease severity score. Other studies on this matter should be conducted with a larger number of participants to confirm the findings of the present study.

Sit-to-stand test in children with bronchiectasis: Does it measure functional exercise capacity?

BACKGROUND

Similar to six-minute walk test (6MWT), sit-to-stand test (STST) is a self-paced test which elicits sub-maximal effort; therefore, it is suggested as an alternative measurement for functional exercise capacity in various pulmonary conditions including COPD and cystic fibrosis. We aimed to investigate the association between 30-second STST (30s-STST) and 6MWT in both children with bronchiectasis (BE) and their healthy counterparts, as well as exploring cardiorespiratory burden and discriminative properties of both tests.

METHODS

Sixty children (6 to 18-year-old) diagnosed with non-cystic fibrosis BE and 20 age-matched healthy controls were included. Both groups performed 30s-STST and 6MWT. Test results, and heart rate, SpO₂ and dyspnea responses to tests were recorded.

RESULTS

Univariate analysis revealed that 30s-STST was able to explain 52% of variance in 6MWT (r = 0.718, p<0.001) in BE group, whereas 20% of variance in healthy controls (r = 0.453, p = 0.045). 6MWT elicited higher changes in heart rate and dyspnea level compared to 30s-STST, indicating it was more physically demanding. Both 30s-STST (21.65±5.28 vs 26.55±3.56 repetitions) and 6MWT (538±85 vs 596±54 m) were significantly lower in BE group compared to healthy controls (p<0.01). Receiver operating characteristic (ROC) curve analysis revealed an area under the ROC curve (UAC) of 0.765 for 30s-STST and 0.693 for 6MWT in identifying the individuals with or without BE (p<0.05). Comparison between AUCs of 30s-STST and 6MWT yielded no significant difference (p = 0.466), indicating both tests had similar discriminative properties.

CONCLUSIONS

30s-STST is found to be a valid alternative measurement for functional exercise capacity in children with BE.

Validity of the Incremental Shuttle Walk Test to Assess Exercise Safety When Initiating Cardiac Rehabilitation in Low-Resource Settings

PURPOSE

To evaluate the validity of the Incremental Shuttle Walk Test (ISWT) for determining risk stratification in cardiac rehabilitation (CR).

METHODS

This is a cross-sectional study at a major CR center in a middle-income country. Clinically stable adult cardiac patients underwent an ISWT and an exercise test (ET), wore a pedometer for 7 d, and completed the Godin-Shepherd Leisure-Time Physical Activity Questionnaire. Metabolic equivalents of task (METs) achieved on the ISWT were calculated.

RESULTS

One hundred fifteen patients were evaluated. The mean ± standard deviation distance on the ISWT was 372.70 ± 128.52 m and METs were 5.03 ± 0.62. The correlation of ISWT distance with ET METs (7.57 ± 2.57), steps/d (4556.71 ± 3280.88), and self-reported exercise (13.08 ± 15.19) was rs = 0.61 (P < .001), rs = 0.37 (P < .001), and rs = 0.20 (P = .031), respectively. Distance on the ISWT accurately predicted METs from the ET (area under the receiver operating characteristic curve = 0.774). The ability to walk ≥410 m on the ISWT predicted, with a specificity of 81.5% and a sensitivity of 65.6%, a functional capacity of ≥7 METs on ET.

CONCLUSION

The ISWT is an alternative way to evaluate functional capacity in CR and can contribute to the process of identifying patients at low risk for a cardiac event during exercise at moderate intensity.

Measuring airway clearance outcomes in bronchiectasis: a review

While airway clearance techniques (ACTs) are recommended for individuals with bronchiectasis, many trials have demonstrated inconsistent benefits or failed to reach their primary outcome. This review determined the most common clinical and patient-reported outcome measures used to evaluate the efficacy of ACTs in bronchiectasis. A literature search of five databases using relevant keywords and filtering for studies published in English, up until the end of August 2019, was completed. Studies included randomised controlled trials, using crossover or any other trial design, and abstracts. Studies were included where the control was placebo, no intervention, standard care, usual care or an active comparator. Adults with bronchiectasis not related to cystic fibrosis were included. Extracted data comprised study authors, design, duration, intervention, outcome measures and results. The search identified 27 published studies and one abstract. The most common clinical outcome measures were sputum volume (n=23), lung function (n=17) and pulse oximetry (n=9). The most common patient-reported outcomes were health-related quality of life (measured with St George's Respiratory Questionnaire, n=4), cough-related quality of life (measured with Leicester Cough Questionnaire, n=4) and dyspnoea (measured with Borg/modified Borg scale, n=8). Sputum volume, lung function, dyspnoea and health- and cough-related quality of life appear to be the most common clinical and patient-reported measures of airway clearance treatment efficacy.

Reliability and responsiveness of incremental shuttle walk test to estimate exercise capacity in patients with pulmonary arterial hypertension

The purpose of the present study was to evaluate the reliability and responsiveness of the incremental shuttle walk test (ISWT) to estimate exercise capacity in patients with pulmonary arterial hypertension (PAH). This was a cross-sectional longitudinal study performed on stable PAH patients (n=30, mean age ± standard deviation, 60±13.6 years) with World Health Organization functional class II & III. Reliability was assessed by comparing the distance covered between ISWT-1 (initial) and ISWT-2 (retest). Responsiveness was determined by comparing the distance covered in the ISWT-3 post pulmonary rehabilitation (PR) to the ISWT-1. The distance covered between ISWT-1 (177±87.85 m) and ISWT-2 (191.67±96.39 m) was not statistically significant. The result of the relative reliability has shown to be excellent with an intraclass correlation coefficient (ICC2,1= 0.98, 95%CI = 0.95-0.99). Absolute reliability was evaluated through the standard error of the measurement and minimal detectable change at a 95% confidence interval (MDC95) were 12.29 and 33.9 m, respectively. Bland Altman plot showed good agreement between the two ISWTs. Following PR, the effect size (ES=0.78) and standardised response mean (SRM=1.50) were moderate and large respectively. ISWT is considered to be a reliable and responsive measure to estimate exercise capacity in patients with PAH. The ISWT may be considered a suitable alternative tool over a 6-min walk test and in the absence of equipment availability or expertise for conducting cardiopulmonary exercise test for the assessment of exercise capacity in these patients.

Physical activity of patients with bronchiectasis compared with healthy counterparts: A cross-sectional study

BACKGROUND

A few studies have implied that patients with bronchiectasis have a more inactive lifestyle than healthy counterparts do. The main objective of this study was to compare physical activity (PA) levels subjectively and objectively between patients with bronchiectasis and healthy individuals using an accelerometer and a questionnaire.

METHODS

The study included 41 patients with bronchiectasis aged 18-65 years and 35 healthy age- and sex-matched control subjects. The PA level was assessed objectively using a multisensorial PA monitor, the SenseWear Armband (SWA), and subjectively with the International Physical Activity Questionnaire (IPAQ). All participants performed the incremental shuttle walk test (ISWT) for the assessment of exercise capacity. Pulmonary function, dyspnea, severity of bronchiectasis, respiratory and peripheral muscle strength, and quality of life were assessed.

RESULTS

The pulmonary function test parameters, respiratory and peripheral muscle strength, exercise capacity, step count, moderate- and vigorous-intensity PA duration were significantly lower in patients with bronchiectasis than in the healthy control group (p < 0.05). Sedentary, moderate, vigorous, and total PA duration measured using the SWA were higher than those obtained using the IPAQ (p < 0.05).

CONCLUSIONS

Patients with bronchiectasis have a reduced PA level compared with healthy counterparts. The IPAQ (based on the subjective estimation of PA) outcomes differed from the SWA outcomes, reinforcing the necessity for a disease-specific PA questionnaire. IPAQ underestimates the physical activity level compared with objective measurements.

Practical approach to establishing pulmonary rehabilitation for people with non-COPD diagnoses

Pulmonary rehabilitation is a core aspect in the management of patients with chronic respiratory diseases. This paper describes a practical approach to establishing pulmonary rehabilitation for patients with non-COPD diagnoses using examples from the interstitial lung disease (ILD), pulmonary hypertension (PH), bronchiectasis and lung cancer patient populations. Aspects of pulmonary rehabilitation, including the rationale, patient selection, setting of programmes, patient assessment and training components (both exercise and non-exercise aspects), are discussed for these patient groups. Whilst there are many similarities in the rationale and application of pulmonary rehabilitation across these non-COPD populations, there are also many subtle differences, which are discussed in detail in this paper. With consideration of these factors, pulmonary rehabilitation programmes can be adapted to facilitate the inclusion of respiratory patients with non-COPD diagnoses.

Home-based exercise therapy in patients awaiting liver transplantation: protocol for an observational feasibility trial

INTRODUCTION

Liver disease is the third most common cause of premature mortality in the UK. Liver failure accelerates frailty, resulting in skeletal muscle atrophy, functional decline and an associated risk of liver transplant waiting list mortality. However, there is limited research investigating the impact of exercise on patient outcomes pre and post liver transplantation. The waitlist period for patients listed for liver transplantation provides a unique opportunity to provide and assess interventions such as prehabilitation.

METHODS AND ANALYSIS

This study is a phase I observational study evaluating the feasibility of conducting a randomised control trial (RCT) investigating the use of a home-based exercise programme (HBEP) in the management of patients awaiting liver transplantation. Twenty eligible patients will be randomly selected from the Queen Elizabeth University Hospital Birmingham liver transplant waiting list. Participants will be provided with an individually tailored 12-week HBEP, including step targets and resistance exercises. Activity trackers and patient diaries will be provided to support data collection. For the initial 6 weeks, telephone support will be given to discuss compliance with the study intervention, achievement of weekly targets, and to address any queries or concerns regarding the intervention. During weeks 6-12, participants will continue the intervention without telephone support to evaluate longer term adherence to the study intervention. On completing the intervention, all participants will be invited to engage in a focus group to discuss their experiences and the feasibility of an RCT.

ETHICS AND DISSEMINATION

The protocol is approved by the National Research Ethics Service Committee North West - Greater Manchester East and Health Research Authority (REC reference: 17/NW/0120). Recruitment into the study started in April 2017 and ended in July 2017. Follow-up of participants is ongoing and due to finish by the end of 2017. The findings of this study will be disseminated through peer-reviewed publications and international presentations. In addition, the protocol will be placed on the British Liver Trust website for public access.

TRIAL REGISTRATION NUMBER

NCT02949505; Pre-results.