Clinical Determinants of Incremental Shuttle Walk Test in Adults with 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.

Functional exercise capacity in patients with ankylosing spondylitis

OBJECTIVE

This study aimed to measure the functional exercise capacity of patients with ankylosing spondylitis (AS) with the incremental shuttle walk test (ISWT), and to determine the factors associated with this test.

METHODS

This cross-sectional study included 54 patients with AS (29 males, 25 females). The ISWT was performed to determine functional exercise capacity. The number of completed shuttles was recorded, and the total incremental shuttle walk distance (ISWD) was calculated. Disease activity was assessed with the Bath AS Disease Activity Index (BASDAI), physical functioning was assessed with the Bath AS Functional Index (BASFI), and spinal mobility was assessed with the Bath AS Mobility Index (BASMI). Upper body and core endurance were assessed by sit-up and push-up tests. Tests were performed in a single session in the order listed.

RESULTS

The mean ISWD of the patients was 462.41 ± 97.96 m, and the subjects reached 50.48% of the predicted ISWD. The ISWD of male subjects was significantly higher than that of females (p < .05). At the end of the test, male subjects reached 60.87% of the age-predicted maximal heart rate, and female subjects reached 55.25%. There was a significant positive moderate correlation between ISWD and height (r = 0.535, p < .01), sit-up test (r = 0.617, p < .01), and push-up test (r = 0.495, p < .01), while there was a negative weak correlation between BASFI (r = -0.344, p = .011) and BASMI (r = -0.280, p = .040).

CONCLUSION

The study showed that functional exercise capacity as assessed by the ISWT decreased in patients with AS. ISWT performance was associated with sex, height, functionality, spinal mobility, and muscular endurance.

A study of the psychometric properties of the Brazilian...Portuguese version of Bronchiectasis Health Questionnaire

INTRODUCTION AND OBJECTIVE

The Bronchiectasis Health Questionnaire (BHQ) is a simple, repeatable, and self-reporting health status questionnaire for bronchiectasis. This study aims to cross-culturally adapt the BHQ into Brazilian Portuguese and evaluate its measurement properties.

METHODS

The participants answered the Saint George...s Respiratory Questionnaire (SGRQ) and the modified Medical Research Council (mMRC) scale for dyspnea. The Brazilian-Portuguese version of the Bronchiectasis Health Questionnaire (BHQ-Brazil) was used at baseline (test) and after 14 days (retest). The psychometric analyses included internal consistency, test-retest reliability, and construct validity: factorial validity, convergent validity, and discriminative validity, agreement, and ceiling and floor effects.

RESULTS

The BHQ-Brazil demonstrated adequate internal consistency (Cronbach...s alpha...=...0.92) and substantial reliability (intraclass correlation coefficient...=...0.86; 95%CI: 0.79...0.90). The exploratory factorial analysis was considered suitable. All items presented a factorial load >0.40. The convergent validity of the BHQ-Brazil with mMRC was moderate (r...=......0.53, p...<...0.001), while concurrent validity with the SGRQ was strong (symptoms: r...=......0.72, activities: r...=......0.60, impact: r...=......0.60, total score: r...=......0.75, all p...<...0.001). The standard error of measurement was 4.81 points. The discriminative validity demonstrated that individuals with more pulmonary exacerbations, colonization by Pseudomonas aeruginosa, worst dyspnea, and a higher number of affected lung lobes presented the lowest quality of life. No floor or ceiling effects were observed.

CONCLUSION

The BHQ-Brazil presents adequate measurement properties to evaluate the impact of bronchiectasis on health-related quality of life, and can be used in clinical and research settings.

Respiratory and Peripheral Muscle Weakness and Body Composition Abnormalities in Non-Cystic Fibrosis Bronchiectasis Patients: Gender Differences

As demonstrated in COPD, bronchiectasis patients may experience respiratory and peripheral muscle dysfunction. We hypothesized that respiratory and peripheral (upper and lower limbs) muscle function and nutritional status may be more significantly altered in female than in males for identical age and disease severity. In mild-to-moderate bronchiectasis patients (n = 150, 114 females) and 37 controls (n = 37, 21 females), radiological extension, maximal inspiratory and expiratory pressures (MIP and MEP), sniff nasal inspiratory pressure (SNIP), hand grip and quadriceps muscle strengths, body composition, and blood analytical biomarkers were explored. Compared to the controls, in all bronchiectasis patients (males and females), BMI, fat-free mass index (FFMI), fat tissue, upper and lower limb muscle strength, and respiratory muscle strength significantly declined, and FFMI, fat tissue, and quadriceps muscle function were significantly lower in female than male patients. In patients with mild-to-moderate bronchiectasis, respiratory and peripheral muscle function is significantly impaired and only partly related to lung disease status. Quadriceps muscle strength was particularly weakened in the female patients and was negatively associated with their exercise tolerance. Muscle weakness should be therapeutically targeted in bronchiectasis patients. Body composition and peripheral muscle function determination should be part of the comprehensive clinical assessment of these patients.

Pulmonary Rehabilitation in Noncystic Fibrosis Bronchiectasis

BACKGROUND

Current guidelines for the treatment of noncystic fibrosis bronchiectasis (NCFB) recommend pulmonary rehabilitation (PR), but to date, there are few studies that have proven its effectiveness.

OBJECTIVE

The main objective of this study was to examine the effect of PR on pulmonary function tests and exercise capacity.

METHOD

The aim of this study was to systematically review the effects of PR in NCFB on (1) forced expiratory volume in the first second (FEV1) and (2) exercise capacity evaluated by the 6-min walk test (6MWT) and the incremental shuttle walk test (ISWT). This meta-analysis was undertaken according to PRISMA recommendations.

RESULTS

This pair-wise meta-analysis included data obtained from studies that enrolled 529 NCFB patients. The FEV1 assessment after PR between the active and control group did not show any significant increase (FEV1 difference 0.084 mL; CI: -0.064, +0.233; p = 0.264), and there was an increasing trend (188 mL; CI: -0 to 0.009, +0.384) at the limits of statistical significance (p = 0.061). Walked distance showed a significant increase in the PR group compared to the control group (ISWT distance difference 070.0 m; CI: 55.2, 84.8; p < 0.001), and this finding was confirmed before and after PR both by the ISWT (68.85 m greater than baseline; CI: 40.52, 97.18; p < 0.001) and by the 6MWT (37.7 m greater than baseline; CI: 20.22, 55.25; p < 0.001).

CONCLUSIONS

PR improves exercise tolerance in NCFB patients, but it has a modest impact on respiratory function.

Desaturation-Distance Ratio During Submaximal and Maximal Exercise Tests and Its Association With Lung Function Parameters in Patients With Lymphangioleiomyomatosis

Background: The desaturation-distance ratio (DDR), the ratio of the desaturation area to the distance walked, is a promising, reliable, and simple physiologic tool for functional evaluation in subjects with interstitial lung diseases. Lymphangioleiomyomatosis (LAM) is a rare neoplastic condition frequently associated with exercise impairment. However, DDR has rarely been evaluated in patients with LAM. Objectives: To assess DDR during maximal and submaximal exercises and evaluate whether DDR can be predicted using lung function parameters. Methods: A cross-sectional study was conducted in a cohort of women with LAM. The 6-min walking test (6MWT) and the incremental shuttle walking test (ISWT) were performed, and DDR was obtained from both tests. The functional parameters were assessed at rest using spirometry and body plethysmography. The pulmonary function variables predictive of DDR were also assessed. Results: Forty patients were included in this study. The mean age was 46 ± 10 years. Airway obstruction, reduced DLCO, and air trapping were found in 60, 57, and 15% of patients, respectively. The distance walked and the DDR for the 6MWT and ISWT were, respectively, 517 ± 65 and 443 ± 127 m; and 6.6 (3.8-10.9) and 8.3 (6.2-12.7). FEV1 (airway obstruction) and reduced DLCO and RV/TLC (air trapping) were independent variables predictive of DDR during exercises field tests [DDR6MWT = 18.66-(0.06 × FEV1%pred)-(0.10 × DLCO%pred) + (1.54 × air trapping),R adjust 2 = 0.43] and maximal [DDRISWT = 18.84-(0.09 × FEV1%pred)-(0.05 × DLCO%pred) + (3.10 × air trapping),R adjust 2 = 0.33]. Conclusion: Our results demonstrated that DDR is a useful tool for functional evaluation during maximal and submaximal exercises in patients with LAM, and it can be predicted using airway obstruction, reduced DLCO, and air trapping.

Incremental Shuttle Walk Distance as an Indicator for Functional Exercise Capacity of Pre-Surgical Patients with Nontuberculous Mycobacterial Lung Disease

The incidence of nontuberculous mycobacterial lung disease (NTMLD) is increasing worldwide, the number of lung surgeries is increasing accordingly. The disease is progressive and is characterized by exertional intolerance, respiratory dysfunctions, and impaired health-related quality of life (HRQOL). Treatment comprises multidrug antibiotic treatment combined with lung resection. The incremental shuttle walk distance (ISWD) is a standard tool for assessing the patients' tolerance to lung resection. The exertional tolerance, physical functions and HRQOL among pre-surgical patients with NTMLD are clinically important, but not fully studied yet from the viewpoint of physiotherapy. The purpose of this study was to explore the clinical significance of ISWD for assessing the exercise capacity of pre-surgical patients with NTMLD. For peripheral muscle evaluation, the strength of the quadriceps femoris muscle was measured. HRQOL was evaluated using scores of the St. George's Respiratory Questionnaire (SGRQ). Thirty-three patients (mean age 54.9 ± 13 years) were enrolled. The mean ISWD was 505 ± 134 m, shorter than the reference values (ISWD %predicted: 96 ± 27%). Regression analysis showed significant associations between ISWD and percent-predicted vital capacity (r = 0.38, p = 0.03) and percent quadriceps force/body weight (r = 0.54, p = 0.001). HRQOL assessed by SGRQ scores was correlated with ISWD (r < -0.4, p < 0.05). Multiple regression analysis showed that ISWD was significantly associated with leg muscle strength and with HRQOL. In conclusion, ISWD is useful to evaluate the exercise capacity among pre-surgical patients with NTMLD.