Incremental Shuttle Walking Test: A Reproducible and Valid Test to Evaluate Exercise Tolerance in Adults With Noncystic 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.

Predictors of reduced incremental shuttle walk test performance in patients with long post-COVID-19

OBJECTIVE

One of the common limitations after COVID-19 pneumonia is the decrease in exercise capacity. The identification of the factors affecting exercise capacity and the assessment of patients at risk are important for determining treatment strategy. This study was conducted to determine the predictors of decreased exercise capacity in long post-COVID-19 patients.

METHODS

We investigated the association of exercise capacity as measured by the incremental shuttle walk test (ISWT) with age, sex, spirometric variables, respiratory and peripheral muscle strength, quality of life, fatigue, hospital anxiety depression scale, chest X-ray involvement, and hospitalization. The patients were divided into three groups: outpatients, inpatients, and ICU patients. Regression analysis was used to determine which parameters were significant predictors of exercise capacity.

RESULTS

Of the 181 patients included in the study, 56 (31%) were female. The mean ISWT in percentage of predicted values (ISWT%pred) was 43.20% in the whole sample, whereas that was 52.89%, 43.71%, and 32.21% in the outpatient, inpatient, and ICU patient groups, respectively. Linear regression analysis showed that predictors of decreased ISWT%pred were sex (b = 8.089; p = 0.002), mMRC scale score (b = -7.004; p ≤ 0.001), FVC%pred (b = 0.151; p = 0.003), and handgrip strength (b = 0.261; p = 0.030).

CONCLUSIONS

In long post-COVID-19 patients, sex, perception of dyspnea, restrictive pattern in respiratory function, and decrease in peripheral muscle strength are predictors of reduced exercise capacity that persists three months after COVID-19. In this context, we suggest that pulmonary rehabilitation might be an important therapy for patients after COVID-19.

Physical activity level and sedentary behavior in patients with bronchiectasis: A systematic review of outcome measures and determinants

BACKGROUND

Changes in respiratory functions negatively affect the physical activity (PA) levels of patients with bronchiectasis. Therefore, detecting the most frequently used assessments of PA is essential as determining related factors and improving PA. This review study aimed to investigate the PA levels, compare levels with the recommended PA guidelines, determine the outcome measurements of PA and examine the determinants related to PA in patients with bronchiectasis.

METHOD

This review was conducted using databases of MEDLINE, Web of Science, and PEDro. The searched terms were the variations of the words "bronchiectasis" and "physical activity". Full texts of cross-sectional studies and clinical trials were included. Two authors independently screened the studies for inclusion.

RESULT

The initial search identified 494 studies. A hundred articles were selected for full-text review. Following the application of the eligibility process, 15 articles were included. Twelve studies used activity monitors and five studies used questionnaires. The studies that used activity monitors presented daily step counts. The mean number of steps ranged between 4657 and 9164 for adult patients. It was approximately 5350 steps/day in older patients. One study investigated children's PA level reported 8229 steps/day. The functional exercise capacity, dyspnea, FEV1 and, quality of life as related determinants with PA have been reported in the studies.

CONCLUSION

PA levels of patients with non-cystic fibrosis bronchiectasis were lower than the recommended levels. The objective measurements were frequently used in PA assessment. In further studies, it is needed to investigate the related determinants of PA in patients.

Efficacy of N-acetylcysteine on idiopathic or postinfective non-cystic fibrosis bronchiectasis: a systematic review and meta-analysis protocol

INTRODUCTION

Non-cystic fibrosis (non-CF) bronchiectasis is a chronic pulmonary disorder that causes destruction and permanent dilatation of the airways, resulting in excessive sputum production, repeated infection and inflammation. A need for high-quality and specialised care has been highlighted in recent years. N-acetylcysteine (NAC) is a widely used mucolytic agent in respiratory diseases that not only possesses a property to enhance secretion clearance, but also exhibits antioxidant and anti-inflammatory effects. However, the efficacy and safety of NAC are not well described in idiopathic or postinfective non-CF bronchiectasis.

OBJECTIVE

This study aims to evaluate the efficacy and safety of NAC in patients with idiopathic or postinfective non-CF bronchiectasis.

METHODS AND ANALYSIS

PubMed/Medline, Embase, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials will be searched from inception to 1 March 2022 for eligible randomised controlled trials that investigating the effects of NAC on exacerbations, health-related quality of life, lung functions, sputum volume and colour, inflammation markers, exercise capacity and adverse events in patients with idiopathic or postinfective non-CF bronchiectasis, with ongoing trials being identified by searches on the websites of Chinese Clinical Trial Registry and ClinicalTrials.gov. Two independent reviewers will identify eligible studies, two will fulfil the data extraction and three will perform the quality appraisal. To generate more accurate analyses, the Grading of Recommendations Assessment, Development and Evaluation will be used to grade the evidence. χ² test and I² statistic will be used to assess heterogeneity. Subgroup analyses and meta-regression will be used to explore potential sources of heterogeneity. The potential publication bias will be examined using funnel plots.

ETHICS AND DISSEMINATION

No research ethics approval is required in this study because it is a systematic review. The results of this study are expected to be disseminated through peer-reviewed journals and conferences.

TRIAL REGISTRATION NUMBER

CRD42021239438.

Decreased incremental shuttle walk test distance characterized by fibrocavitary lesions in non-tuberculous mycobacterial pulmonary disease

BACKGROUND

Patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD) have impaired exercise capacity, but the underlying factors are unknown. We investigated the characteristics of patients with NTM-PD and impaired exercise capacity.

METHODS

In total, 149 patients with NTM-PD participated in this study. Patients completed the incremental shuttle walk test (ISWT) to assess exercise capacity. Peripheral muscle strength and pulmonary function were also assessed. Radiological findings were classified into three phenotypes: non-cavitary nodular bronchiectatic (NC-NB) form, cavitary nodular bronchiectatic form, and fibrocavitary (FC) form.

RESULTS

The median ISWT distance (ISWD) and %ISWD were 450 meters and 88%. Participants were classified into three groups according to %ISWD, with %ISWD <60% as the severely decreased group, 60%-80% as the moderately decreased group, and >80% as the normal or mildly decreased group. In a comparison of %ISWD among phenotypes, FC form had significantly lower %ISWD than those with NC-NB form. In the severely decreased group, peripheral muscle strength and pulmonary function were significantly lower than the other two groups. From a radiological standpoint, significantly more patients had FC form in the group with severely decreased %ISWD.

CONCLUSIONS

Decreased ISWD is characterized by a deterioration in physical function and the presence of FC lesions in NTM-PD.

Exercise-induced desaturation in subjects with non-cystic fibrosis bronchiectasis: laboratory-based tests versus field-based exercise tests

OBJECTIVE

To investigate the validity of field walking tests to identify exercise-induced hypoxemia and to compare cardiorespiratory responses and perceived effort between laboratory-based and field-based exercise tests in subjects with bronchiectasis.

METHODS

This was a cross-sectional study involving 72 non-oxygen-dependent participants (28 men; mean age = 48.3 ± 14.5 years; and mean FEV1 = 54.1 ± 23.4% of the predicted value). The participants underwent cardiopulmonary exercise testing (CPET) on a treadmill and constant work-rate exercise testing (CWRET) on the same day (1 h apart). In another visit, they underwent incremental shuttle walk testing (ISWT) and endurance shuttle walk testing (ESWT; 1 h apart). Desaturation was defined as a reduction in SpO2 ≥ 4% from rest to peak exercise.

RESULTS

CPET results were compared with ISWT results, as were CWRET results with ESWT results. There was no difference in the magnitude of desaturation between CPET and ISWT (-7.7 ± 6.3% vs. -6.6 ± 5.6%; p = 0.10) and between CWRET and ESWT (-6.8 ± 5.8% vs. -7.2 ± 6.3%; p = 0.50). The incremental tests showed an agreement in the magnitude of desaturation in the desaturation and no desaturation groups (42 and 14 participants, respectively; p < 0.01), as did the endurance tests (39 and 16 participants; p < 0.01). The magnitude of desaturation was similar among the participants who did or did not reach at least 85% of the maximum predicted HR.

CONCLUSIONS

Field exercise tests showed good precision to detect desaturation. Field tests might be an alternative to laboratory tests when the clinical question is to investigate exercise-induced desaturation in subjects with bronchiectasis.

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.

Reliability, Validity, and Responsiveness of the Incremental Shuttle Walk Test in Patients With Interstitial Lung Disease

PURPOSE

To determine the reliability, validity, and responsiveness of the incremental shuttle walk test (ISWT) in patients with interstitial lung disease (ILD).

METHODS

This was a cross-sectional longitudinal study. Patients (n = 27, 10 males; mean age ± SD, 61 ± 9.8 y) with ILD of any etiology, who participated in an outpatient pulmonary rehabilitation (PR) program, were recruited. Reliability was determined by comparing the distance covered in meters between the ISWT-1 and the ISWT-2. Validity was assessed by correlating the distance covered in the ISWT-1, with the maximum oxygen consumption ((Equation is included in full-text article.)O2max) obtained through cardiopulmonary exercise testing and distance covered during the 6-min walk test (6MWT). Responsiveness was assessed by comparing the distance covered in the ISWT-3, undertaken after the completion of PR, to the ISWT-1.

RESULTS

The distance covered was equivalent between the ISWT-1 (216.7 ± 64.9 m) and the ISWT-2 (220.7 ± 67.3 m), with an excellent intraclass correlation coefficient (ICC2,1 = 0.91; 95% CI, 0.81-0.95). The standard error of measurement and minimal detectable change at the 95% CI (MDC95) values for the ISWT were 19.5 m and 53.9m, respectively. There were significant correlations between the distance covered on the ISWT and (Equation is included in full-text article.)O2max (r = 0.79, P < .0001) and the distance covered on the 6MWT (r = 0.76, P < .0001). Following PR, the change in the ISWT distance showed large effect size (ES = 0.85) and standardized response mean (SRM = 1.58).

CONCLUSIONS

The ISWT is a reliable, valid, and responsive measure of estimated functional capacity in patients with ILD.

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.

Brazilian consensus on non-cystic fibrosis bronchiectasis

Bronchiectasis is a condition that has been increasingly diagnosed by chest HRCT. In the literature, bronchiectasis is divided into bronchiectasis secondary to cystic fibrosis and bronchiectasis not associated with cystic fibrosis, which is termed non-cystic fibrosis bronchiectasis. Many causes can lead to the development of bronchiectasis, and patients usually have chronic airway symptoms, recurrent infections, and CT abnormalities consistent with the condition. The first international guideline on the diagnosis and treatment of non-cystic fibrosis bronchiectasis was published in 2010. In Brazil, this is the first review document aimed at systematizing the knowledge that has been accumulated on the subject to date. Because there is insufficient evidence on which to base recommendations for various treatment topics, here the decision was made to prepare an expert consensus document. The Brazilian Thoracic Association Committee on Respiratory Infections summoned 10 pulmonologists with expertise in bronchiectasis in Brazil to conduct a critical assessment of the available scientific evidence and international guidelines, as well as to identify aspects that are relevant to the understanding of the heterogeneity of bronchiectasis and to its diagnostic and therapeutic management. Five broad topics were established (pathophysiology, diagnosis, monitoring of stable patients, treatment of stable patients, and management of exacerbations). After this subdivision, the topics were distributed among the authors, who conducted a nonsystematic review of the literature, giving priority to major publications in the specific areas, including original articles, review articles, and systematic reviews. The authors reviewed and commented on all topics, producing a single final document that was approved by consensus.

Physical activity associates with disease characteristics of severe asthma, bronchiectasis and COPD

BACKGROUND AND OBJECTIVE

Physical activity (PA) in obstructive airway diseases (OAD) is likely to be impaired but this has not been extensively studied outside of chronic obstructive pulmonary disease (COPD). We describe PA levels in severe asthma and bronchiectasis compared to moderate-severe COPD and to controls, and tested the cross-sectional associations of PA (steps/day) with shared disease characteristics in the OAD group.

METHODS

Adults with OAD (severe asthma = 62, COPD = 67, bronchiectasis = 60) and controls (n = 63) underwent a multidimensional assessment, including device-measured PA levels.

RESULTS

The OAD group included 189 participants (58.7% females), with median (interquartile range) age of 67 (58-72) years and mean forced expiratory volume in the first second (FEV₁ ) % predicted of 69.4%. Demographic characteristics differed between groups. Compared to controls (52.4% females, aged 55 (34-64) years, median 7640 steps/day), those with severe asthma, bronchiectasis and COPD accumulated less steps/day: median difference of -2255, -2289, and -4782, respectively (P ≤ 0.001). Compared to COPD, severe asthma and bronchiectasis participants accumulated more steps/day: median difference of 2375 and 2341, respectively (P ≤ 0.001). No significant differences were found between the severe asthma and bronchiectasis group. Exercise capacity, FEV₁ % predicted, dyspnoea and systemic inflammation differed between groups, but were each significantly associated with steps/day in OAD. In the multivariable model adjusted for all disease characteristics, exercise capacity and FEV₁ % predicted remained significantly associated.

CONCLUSION

PA impairment is common in OAD. The activity level was associated with shared characteristics of these diseases. Interventions to improve PA should be multifactorial and consider the level of impairment and the associated characteristics.

Validation of the Incremental Shuttle Walk Test as a Clinical End Point in Bronchiectasis

BACKGROUND

A validated clinical end point is needed to assess response to therapies in bronchiectasis.

OBJECTIVES

The goal of this study was to assess the reliability, validity, and responsiveness of the incremental shuttle walk test (ISWT) as a clinical end point in bronchiectasis.

METHODS

In clinically stable patients (n = 30), the ISWT was performed twice, 6 months apart. Correlation between the St. George's Respiratory Questionnaire (SGRQ) and the ISWT (n = 94) was performed. The 1-year gentamicin study was reanalyzed to assess the area under the curve (percent change of ISWT with a ≥ 4 unit improvement in total SGRQ). ISWT was performed prior to and following 14 days of antibiotics for an exacerbation (94 oral courses and 30 IV courses, n = 124) and reanalysis of the 1-year gentamicin study (n = 57).

RESULTS

The ISWT did not significantly change over 6 months while clinically stable. The ISWT correlated inversely with the SGRQ (rs = -0.60; P < .0001), Bronchiectasis Severity Index score (rs = -0.44; P < .0001), and sedentary time (rs = -0.48; P = .0007) but correlated with physical activity (rs = 0.42; P = .004). The area under the curve for percent change in ISWT with ≥ 4 unit improvement in SGRQ was 0.79 (95% CI, 0.66-0.91; P = .001). A threshold of 5% improvement in the ISWT had a 92% sensitivity but 50% specificity, and from the responsiveness studies would capture 73% of all patients.

CONCLUSIONS

This study confirmed the ISWT to be reliable, valid, and responsive to change in patients with bronchiectasis. The authors propose that a minimum clinically important difference of 5% improvement in the ISWT would be a useful objective end point to assess therapies in bronchiectasis.

Determinants of Peripheral Muscle Strength and Activity in Daily Life in People With Bronchiectasis

BACKGROUND

Bronchiectasis is characterized by a progressive structural lung damage, recurrent infections and chronic inflammation which compromise the exertion tolerance, and may have an impact on skeletal muscle function and physical function.

OBJECTIVE

The purpose of this study was to compare peripheral muscle strength, exercise capacity, and physical activity in daily life between participants with bronchiectasis and controls and to investigate the determinants of the peripheral muscle strength and physical activity in daily life in bronchiectasis.

DESIGN

This study used a cross-sectional design.

METHODS

The participants' quadriceps femoris and biceps brachii muscle strength was measured. They performed the incremental shuttle walk test (ISWT) and cardiopulmonary exercise testing, and the number of steps/day was measured by a pedometer.

RESULTS

Participants had reduced quadriceps femoris muscle strength (mean difference to control group = 7 kg, 95% CI = 3.8-10.1 kg), biceps brachii muscle strength (2.1 kg, 95% CI = 0.7-3.4 kg), ISWT (227 m, 95% CI = 174-281 m), peak VO2 (6.4 ml/Kg/min, 95% CI = 4.0-8.7 ml/Kg/min), and number of steps/day (3,332 steps/day, 95% CI = 1,758-4,890 steps/day). A lower quadriceps femoris strength is independently associated to an older age, female sex, lower body mass index (BMI), higher score on the modified Medical Research Council scale, and shorter distance on the ISWT (R2 = 0.449). Biceps brachii strength is independently associated with sex, BMI, and dyspnea (R2 = 0.447). The determinants of number of daily steps were dyspnea and distance walked in ISWT, explaining only 27.7% of its variance.

LIMITATIONS

Number of steps per day was evaluated by a pedometer.

CONCLUSIONS

People with bronchiectasis have reduced peripheral muscle strength, and reduced aerobic and functional capacities, and they also are less active in daily life. Modifiable variables such as BMI, dyspnea, and distance walked on the ISWT are associated with peripheral muscle strength and physical activity in daily life.

Clinical Determinants of Incremental Shuttle Walk Test in Adults with Bronchiectasis

INTRODUCTION

Exercise capacity is impaired in patients with bronchiectasis. Incremental shuttle walk test (ISWT) stresses cardiorespiratory system physiologically to symptom-limited maximal exercise capacity. The purpose of this study was to investigate the clinical determinants of ISWT in adults with non-cystic fibrosis (CF) bronchiectasis.

METHODS

Forty-one clinically stable bronchiectasis patients aged 18-72 years (27 females, 14 males) participated in the study. Subjects' demographics and physical characteristics were recorded. Bronchiectasis Severity Index was used to identify disease severity. Pulmonary function test was performed. Dyspnea perception was assessed using the modified Medical Research Council Dyspnea Scale. Maximum inspiratory and expiratory pressures were measured. Peripheral muscle strength using a hand held dynamometer was measured. ISWT was performed to determine exercise capacity. Fatigue Severity Scale, Hospital Anxiety and Depression Scale, Leicester Cough Questionnaire were used to determine fatigue, psychosocial status, and quality of life.

RESULTS

Patients' mean ISWT distance was 469.5 m. The ISWT distance was significantly related with age (r = - 0.472), height (r = 0.469), gender (r = 0.520), FEV₁ (r = 0.651), and FVC (r = 0.545, p < 0.05). Quadriceps muscle strength was higher in males (p = 0.001) as compared to females. Age and gender were identified as independent predictors of the ISWT, explaining 42% of variance in ISWT distance (r = 0.649, r² = 0.421, F_(2,38) = 13.794, p < 0.001).

CONCLUSION

The clinical determinants of ISWT in clinically stable patients with non-CF bronchiectasis are age and gender. Pulmonary function, dyspnea perception, muscle strength, disease severity, fatigue, psychosocial factors, and health-related quality of life seems to have an independent effect on ISWT in this group of patients with bronchiectasis.

Does home-based pulmonary rehabilitation improve functional capacity, peripheral muscle strength and quality of life in patients with bronchiectasis compared to standard care?

BACKGROUND

Home-based pulmonary rehabilitation is a promising intervention that may help patients to overcome the barriers to undergoing pulmonary rehabilitation. However, home-based pulmonary rehabilitation has not yet been investigated in patients with bronchiectasis.

OBJECTIVES

To investigate the effects of home-based pulmonary rehabilitation in patients with bronchiectasis.

METHODS

An open-label, randomized controlled trial with 48 adult patients with bronchiectasis will be conducted.

INTERVENTIONS

The program will consist of three sessions weekly over a period of 8 weeks. Aerobic exercise will consist of stepping on a platform for 20min (intensity: 60-80% of the maximum stepping rate in incremental step test). Resistance training will be carried out using an elastic band for the following muscles: quadriceps, hamstrings, deltoids, and biceps brachii (load: 70% of maximum voluntary isometric contraction).

CONTROL

The patients will receive an educational manual and a recommendation to walk three times a week for 30min. All patients will receive a weekly phone call to answer questions and to guide the practice of physical activity. The home-based pulmonary rehabilitation group also will receive a home visit every 15 days.

MAIN OUTCOME MEASURES

incremental shuttle walk test, quality of life, peripheral muscle strength, endurance shuttle walk test, incremental step test, dyspnea, and physical activity in daily life. The assessments will be undertaken at baseline, after the intervention, and 8 months after randomization.

DISCUSSION

The findings of this study will determine the clinical benefits of home-based pulmonary rehabilitation and will contribute to future guidelines for patients with bronchiectasis.

TRIAL REGISTRATION

www.ClinicalTrials.gov (NCT02731482). https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S00060X6&selectaction=Edit&uid=U00028HR&ts=2&cx=1jbszg.

Reliability and validity of an audio signal modified shuttle walk test

Background:

The audio signal in the conventionally accepted protocol of shuttle walk test (SWT) is not well-understood by the patients and modification of the audio signal may improve the performance of the test.

Objectives:

The aim of this study is to study the validity and reliability of an audio signal modified SWT, called the Singla-Richa modified SWT (SWT_SR), in healthy normal adults.

Patients and Methods:

In SWT_SR, the audio signal was modified with the addition of reverse counting to it. A total of 54 healthy normal adults underwent conventional SWT (CSWT) at one instance and two times SWT_SR on the same day. The validity was assessed by comparing outcomes of the SWT_SR to outcomes of CSWT using the Pearson correlation coefficient and Bland–Altman plot. Test-retest reliability of SWT_SR was assessed using the intraclass correlation coefficient (ICC). The acceptability of the modified test in comparison to the conventional test was assessed using Likert scale.

Results:

The distance walked (mean ± standard deviation) in the CSWT and SWT_SR test was 853.33 ± 217.33 m and 857.22 ± 219.56 m, respectively (Pearson correlation coefficient - 0.98; P < 0.001) indicating SWT_SR to be a valid test. The SWT_SR was found to be a reliable test with ICC of 0.98 (95% confidence interval: 0.97–0.99). The acceptability of SWT_SR was significantly higher than CSWT.

Conclusions:

The SWT_SR with modified audio signal with reverse counting is a reliable as well as a valid test when compared with CSWT in healthy normal adults. It better understood by subjects compared to CSWT.

Aetiology of bronchiectasis in adults: A systematic literature review

While identifying the underlying aetiology is a key part of bronchiectasis management, the prevalence and impact of identifying the aetiologies on clinical management remain unclear. We aimed to determine the etiological spectrum of bronchiectasis, and how often etiological assessment could lead to the changes in patients' management. A comprehensive search was conducted using MEDLINE (via PubMed) and EMBASE for observational studies published before October 2015 reporting aetiologies in adults with bronchiectasis. Of the 8216 citations identified, 56 studies including 8608 adults with bronchiectasis were relevant for this systematic review. The crude prevalence for the identified aetiologies ranged from 18% to 95%, which possibly resulted from the differences in the geographic regions and diagnostic workup. Post-infective (29.9%), immunodeficiency (5%), chronic obstructive pulmonary disease (3.9%), connective tissue disease (3.8%), ciliary dysfunction (2.5%), allergic bronchopulmonary aspergillosis (2.6%) were the most common aetiologies. In 1577 patients (18.3%), identifying the aetiologies led to changes in patient's management. Aetiologies varied considerably among different geographic regions (P < 0.001). Intensive investigations of these aetiologies might help change patient's management and therefore should be incorporated into routine clinical practice.

Validity and Reliability of the Chronic Respiratory Disease Questionnaire in Elderly Individuals with Mild to Moderate Non-Cystic Fibrosis Bronchiectasis

BACKGROUND

The chronic respiratory disease questionnaire (CRDQ) is designed to assess health-related quality of life (HRQOL) in chronic respiratory conditions, but its reliability, validity and responsiveness in individuals with mild to moderate non-cystic fibrosis (CF) bronchiectasis are unclear.

OBJECTIVES

This study aimed to determine measurement properties of the CRDQ in non-CF bronchiectasis.

METHODS

Participants with non-CF bronchiectasis involved in a randomised controlled trial of exercise training were recruited. Internal consistency was assessed using Cronbach's α. Over 8 weeks, reliability was evaluated using intra-class correlation coefficients and Bland-Altman analysis for measures of agreement. Convergent and divergent validity was assessed by correlations with the other HRQOL questionnaires and the Hospital Anxiety and Depression Scale (HADS). The responsiveness to exercise training was assessed using effect sizes and standardised response means.

RESULTS

Eighty-five participants were included (mean age ± SD, 64 ± 13 years). Internal consistency was adequate (>0.7) for all CRDQ domains and the total score. Test-retest reliability ranged from 0.69 to 0.85 for each CRDQ domain and was 0.82 for the total score. Dyspnoea (CRDQ) was related to St George's respiratory questionnaire (SGRQ) symptoms only (r = 0.38), with no relationship to the Leicester cough questionnaire (LCQ) or HADS. Moderate correlations were found between the total score of the CRDQ, the SGRQ (rs = -0.49) and the LCQ score (rs = 0.51). Lower CRDQ scores were associated with higher anxiety and depression (rs = -0.46 to -0.56). The responsiveness of the CRDQ was small (effect size 0.1-0.24).

CONCLUSIONS

The CRDQ is a valid and reliable measure of HRQOL in mild to moderate non-CF bronchiectasis, but responsiveness was limited.

Sedentary behaviour and physical activity in bronchiectasis: a cross-sectional study

BACKGROUND

The impact of bronchiectasis on sedentary behaviour and physical activity is unknown. It is important to explore this to identify the need for physical activity interventions and how to tailor interventions to this patient population. We aimed to explore the patterns and correlates of sedentary behaviour and physical activity in bronchiectasis.

METHODS

Physical activity was assessed in 63 patients with bronchiectasis using an ActiGraph GT3X+ accelerometer over seven days. Patients completed: questionnaires on health-related quality-of-life and attitudes to physical activity (questions based on an adaption of the transtheoretical model (TTM) of behaviour change); spirometry; and the modified shuttle test (MST). Multiple linear regression analysis using forward selection based on likelihood ratio statistics explored the correlates of sedentary behaviour and physical activity dimensions. Between-group analysis using independent sample t-tests were used to explore differences for selected variables.

RESULTS

Fifty-five patients had complete datasets. Average daily time, mean(standard deviation) spent in sedentary behaviour was 634(77)mins, light-lifestyle physical activity was 207(63)mins and moderate-vigorous physical activity (MVPA) was 25(20)mins. Only 11% of patients met recommended guidelines. Forced expiratory volume in one-second percentage predicted (FEV1% predicted) and disease severity were not correlates of sedentary behaviour or physical activity. For sedentary behaviour, decisional balance 'pros' score was the only correlate. Performance on the MST was the strongest correlate of physical activity. In addition to the MST, there were other important correlate variables for MVPA accumulated in ≥10-minute bouts (QOL-B Social Functioning) and for activity energy expenditure (Body Mass Index and QOL-B Respiratory Symptoms).

CONCLUSIONS

Patients with bronchiectasis demonstrated a largely inactive lifestyle and few met the recommended physical activity guidelines. Exercise capacity was the strongest correlate of physical activity, and dimensions of the QOL-B were also important. FEV1% predicted and disease severity were not correlates of sedentary behaviour or physical activity. The inclusion of a range of physical activity dimensions could facilitate in-depth exploration of patterns of physical activity. This study demonstrates the need for interventions targeted at reducing sedentary behaviour and increasing physical activity, and provides information to tailor interventions to the bronchiectasis population.

TRIAL REGISTRATION

NCT01569009 ("Physical Activity in Bronchiectasis").

Does the Incremental Shuttle Walking Test require maximal effort in healthy subjects of different ages?

OBJECTIVE

To evaluate if the Incremental Shuttle Walking Test (ISWT) requires maximal effort in healthy subjects of different ages.

DESIGN

Cross-sectional.

SETTING

University-based research laboratory.

PARTICIPANTS

331 healthy subjects separated into six groups according to age: G1, 18 to 28 years; G2, 29 to 39 years; G3, 40 to 50 years; G4, 51 to 61 years; G5, 62 to 72 years and; G6, 73 to 83 years.

MAIN OUTCOME MEASURES

Two ISWTs were performed and participants were permitted to run and to exceed 12 levels during the test, if necessary. Heart rate (HR) and symptoms of dyspnoea and fatigue were recorded before and after the test, and the percentage of age-predicted maximal HR (HRmax) was calculated. Maximal effort was defined as HRmax >90% of age-predicted HRmax.

RESULTS

Almost 31% of the subjects exceeded 12 levels in the ISWT. At the end of the test, all groups presented a median [interquartile range] HR greater than 90% of HRmax (G1: 100 [95 to 104]; G2: 100 [96 to 105]; G3: 103 [97 to 108]; G4: 99 [91 to 106]; G5: 96 [87 to 106] and G6: 96 [91 to 109]% HRmax). Regarding symptoms, all groups showed higher values after the test (P<0.05). A multiple logistic regression analysis identified female gender, older age and a lower HR before the test as determinants of not achieving 90% of HRmax at the end of the test.

CONCLUSIONS

The ISWT requires maximal effort in healthy individuals, but for that it is necessary to extend the test beyond twelve levels. Female gender, older age and lower heart rate before the test are the determinants of not reaching maximal effort.

Minimal important difference in field walking tests in non-cystic fibrosis bronchiectasis following exercise training

BACKGROUND

The 6-min walk distance (6MWD) and incremental shuttle walk distance (ISWD) are clinically meaningful measures of exercise capacity in people with non-cystic fibrosis (CF) bronchiectasis, but the change in walking distance which constitutes clinical benefit is undefined. This study aimed to determine the minimal important difference for the 6MWD and ISWD in non-CF bronchiectasis.

METHODS

Thirty-seven participants with mean FEV1 70% predicted completed both field walking tests before and after an 8-week exercise program. The minimal important difference was calculated using a distribution-based and anchor-based method, with the global rating of change scale used.

RESULTS

The mean change in 6MWD in participants who reported themselves to be unchanged was 10 m, compared to 36 m (small change) and 45 m (substantial change) (p = 0.01). For the ISWD, the mean change in participants who reported themselves to be unchanged was 33 m, compared to 54 m (small change) and 73 m (substantial change) (p = 0.04). The anchor-based method defined the minimal important difference for 6MWD as 24.5 m (AUC 0.76, 95% CI 0.61-0.91) and for ISWD as 35 m (AUC 0.88, 95% CI 0.73-0.99), based on participant's global rating of change. The distribution-based method indicated a value of 22.3 m for the 6MWD and 37 m for the ISWD. There was excellent agreement between the two methods for the 6MWD (kappa = 0.91) and the ISWD (kappa = 0.92).

CONCLUSIONS

Small changes in 6MWD and ISWD may represent clinically important benefits in people with non-CF bronchiectasis. These data are likely to assist in the interpretation of change in exercise capacity following intervention.