Evaluating physical capacity in patients with chronic obstructive pulmonary disease: comparing the shuttle walk test with the encouraged 6-minute walk test

Investigation of Factors Affecting Shuttle Walking Performance at Increased Speed for Patients with Chronic Obstructive Pulmonary Disease

The aim of this study was to examine the factors affecting the shuttle walking test (SWT) in patients with chronic obstructive pulmonary disease (COPD). A total of 29 patients with COPD (the COPD group) and a healthy group (HG) of 34 women aged between 55 and 74 years were included in the study. After the pulmonary function profiles of the participants were assessed, and the SWT was performed. Walking distances, walking speeds, and SWT levels (SWT-L) were determined with the SWT. Before and after the SWT, the heart rate (HR), oxygen saturation level (SPO2), and Borg scale (perceived exertion (BSe) and dyspnea (BSd)) results were analyzed with a paired sample t-test. The dyspnea levels during activity of daily living were determined with the Medical Research Council (MRC) dyspnea scale, and the relationship between MRC dyspnea (MRCD) and walking distance, speed, and SWT-L was tested using multiple linear regression and Pearson correlation analysis. The walking distance, speed, and SWT-L were lower in the COPD group (p < 0.001) than in the HG. The HR values before and after the SWT changed significantly in the COPD group and the HG (p< 0.001), and the effect size was higher in the COPD group. Although the BSe and BSd results before and after the SWT in the COPD group increased significantly (p < 0.001), they did not change in the HG. There was a highly negative correlation between MRCD and walking distance, speed, and SWT-L in the COPD group (p = 0.002, p = 0.000, and p = 0.001, respectively), but no correlation was found in the HG. The results showed that the HR, perceived exertion, and dyspnea levels of women with COPD whose respiratory functions were lower than the HG were significantly affected on the SWT.

Clinical use of the modified shuttle test in children with cystic fibrosis: Is one test sufficient?

OBJECTIVE

To evaluate the reproducibility of the modified shuttle test (MST) and to determine whether the test needs to be performed more than once to assess the exercise capacity of children and adolescents with cystic fibrosis (CF).

METHODS

This was a longitudinal study including patients diagnosed with CF aged more than 6 years. The participants were followed for a period of 9 months and were evaluated at three different time points (visits 1, 2, and 3). Spirometric, anthropometric, clinical, and genetic data were collected, and two MSTs were performed at each visit.

RESULTS

Forty-eight clinically stable volunteers with a mean age of 10.1 ± 2.7 years were initially included. The reproducibility of the test was evaluated using the distance achieved (DA) as the main variable. There were no significant differences in the DA (visit 1, p = .23; visit 2, p = .24; visit 3, p = .85), baseline heart rate (HR) (visit 1, p = .35; visit 2, p = .20; visit 3, p = .98), and peak HR (visit 1, p = .16; visit 2, p = .94; visit 3, p = .23) between the tests performed at each visit. The test-retest reliability demonstrated a high intraclass correlation coefficient at all visits (visit 1, 2, and 3: 0.83, 0.90, and 0.80, respectively) and the variation in HR was the main factor associated with the DA in the MST over time.

CONCLUSION

The MST was found to be a reproducible and reliable test. The data presented here support the use of a single MST to evaluate and monitor exercise capacity of patients with CF during clinic visits.

Improvement in lung function and functional capacity in morbidly obese women subjected to bariatric surgery

OBJECTIVE

To determine whether weight loss in women with morbid obesity subjected to bariatric surgery alters lung function, respiratory muscle strength, functional capacity and the level of habitual physical activity and to investigate the relationship between these variables and changes in both body composition and anthropometrics.

METHODS

Twenty-four women with morbid obesity were evaluated with regard to lung function, respiratory muscle strength, functional capacity, body composition, anthropometrics and the level of habitual physical activity two weeks prior to and six months after bariatric surgery.

RESULTS

Regarding lung function, mean increases of 160 mL in slow vital capacity, 550 mL in expiratory reserve volume, 290 mL in forced vital capacity and 250 mL in forced expiratory volume in the first second as well as a mean reduction of 490 mL in inspiratory capacity were found. Respiratory muscle strength increased by a mean of 10 cmH2O of maximum inspiratory pressure, and a 72-meter longer distance on the Incremental Shuttle Walk Test demonstrated that functional capacity also improved. Significant changes also occurred in anthropometric variables and body composition but not in the level of physical activity detected using the Baecke questionnaire, indicating that the participants remained sedentary. Moreover, correlations were found between the percentages of lean and fat mass and both inspiratory and expiratory reserve volumes.

CONCLUSION

The present data suggest that changes in body composition and anthropometric variables exerted a direct influence on functional capacity and lung function in the women analyzed but exerted no influence on sedentarism, even after accentuated weight loss following bariatric surgery.

Systematic review of the association between exercise tests and patient-reported outcomes in patients with chronic obstructive pulmonary disease

Introduction

Chronic obstructive pulmonary disease (COPD) is an increasingly common cause of death worldwide. Its cardinal symptoms include breathlessness and severely reduced exercise capacity. Several patient-reported outcome (PRO) measures are used to assess health-related quality of life (HRQoL), functional performance, and breathlessness in patients with COPD. Exercise testing is employed to measure functional performance objectively, which is generally believed to impact on overall HRQoL. However, the extent to which commonly used laboratory- and field-based exercise test results correlate with PROs has not been systematically assessed.

Materials and methods

A search of Embase, MedLine, and the Cochrane Library identified primary publications in English that reported data on the correlations (Pearson’s r or Spearman’s ρ) between the outcomes of exercise tests and HRQoL and breathlessness PROs. Studies reporting on the following tests were included: 6-minute walk test (6MWT), 12MWT, incremental and endurance shuttle walk tests, incremental and endurance cycle ergometer tests, and treadmill tests.

Results

Of 3,205 articles screened, 28 were deemed eligible for inclusion. The most commonly reported HRQoL PRO measure was the St George’s Respiratory Questionnaire (13 studies), and the most commonly reported breathlessness PRO measure was the Baseline Dyspnea Index (six studies). The St George’s Respiratory Questionnaire appears to correlate very weakly to moderately with the 6MWT, and breathlessness PROs appear to be moderately to strongly associated with 6MWT outcomes. Across all studies, the 6MWT was the most commonly reported exercise test. Very few publications reporting associations between other exercise tests and PRO measures were found.

Conclusion

This review found evidence to support the association of 6MWT outcomes with HRQoL and breathlessness PROs. There were limited data showing correlations with the outcomes of other exercise tests. Further work is required to examine the associations between these PROs and exercise test outcomes.

Functional Status Assessment of Patients With COPD: A Systematic Review of Performance-Based Measures and Patient-Reported Measures

Presently, there is no recommendation on how to assess functional status of chronic obstructive pulmonary disease (COPD) patients. This study aimed to summarize and systematically evaluate these measures.Studies on measures of COPD patients' functional status published before the end of January 2015 were included using a search filters in PubMed and Web of Science, screening reference lists of all included studies, and cross-checking against some relevant reviews. After title, abstract, and main text screening, the remaining was appraised using the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) 4-point checklist. All measures from these studies were rated according to best-evidence synthesis and the best-rated measures were selected.A total of 6447 records were found and 102 studies were reviewed, suggesting 44 performance-based measures and 14 patient-reported measures. The majority of the studies focused on internal consistency, reliability, and hypothesis testing, but only 21% of them employed good or excellent methodology. Their common weaknesses include lack of checks for unidimensionality, inadequate sample sizes, no prior hypotheses, and improper methods. On average, patient-reported measures perform better than performance-based measures. The best-rated patient-reported measures are functional performance inventory (FPI), functional performance inventory short form (FPI-SF), living with COPD questionnaire (LCOPD), COPD activity rating scale (CARS), University of Cincinnati dyspnea questionnaire (UCDQ), shortness of breath with daily activities (SOBDA), and short-form pulmonary functional status scale (PFSS-11), and the best-rated performance-based measures are exercise testing: 6-minute walk test (6MWT), endurance treadmill test, and usual 4-meter gait speed (usual 4MGS).Further research is needed to evaluate the reliability and validity of performance-based measures since present studies failed to provide convincing evidence. FPI, FPI-SF, LCOPD, CARS, UCDQ, SOBDA, PFSS-11, 6MWT, endurance treadmill test, and usual 4MGS performed well and are preferable to assess functional status of COPD patients.

Systematic Review of the Association Between Laboratory- and Field-Based Exercise Tests and Lung Function in Patients with Chronic Obstructive Pulmonary Disease

Introduction: Typical symptoms of chronic obstructive pulmonary disease (COPD) include breathlessness and reduced exercise capacity. Several laboratory- and field-based exercise tests are used to assess the exercise capacity of patients with COPD. It is unclear whether these exercise tests reflect the spirometric measures recommended for diagnosis of COPD. We therefore aimed to systematically assess the correlation between these exercise tests and common measures of lung function. Methods: A search of Embase™, MEDLINE^® and The Cochrane Library identified primary publications in English that reported data on the correlations (Pearson's r or Spearman's rho) between the outcomes of exercise tests and the physiological measures of interest: forced expiratory volume in 1 second (FEV₁), forced vital capacity, inspiratory capacity and arterial oxygen saturation. We included studies reporting on the following exercise tests: 6- and 12-minute walk tests (6MWT and 12 MWT), incremental and endurance shuttle walk tests, incremental and endurance cycle ergometer tests, and treadmill tests. Results: Of 1781 articles screened, 45 were ultimately deemed eligible for inclusion in this review. The most commonly reported lung function variable was FEV₁ (reported by 39 studies); the most commonly reported exercise test was the 6-minute walk test (reported by 24 studies). FEV₁ appears to correlate moderately-to-strongly with 6MWT and 12MWT; and moderately-to-very strongly with incremental cycle ergometer tests (ICET); evidence for other exercise tests was limited. Conclusion: There is evidence that 6MWT, 12MWT and ICET correlate with FEV₁ to some degree; - evidence for associations of other exercise tests with measures of lung function in patients with COPD is limited. Clinicians must consider this when deciding to use these tests. Further comparisons of these tests must be made in order to assess which physiological and hemodynamic characteristics they reflect in patients with COPD.

Comparison of laboratory- and field-based exercise tests for COPD: a systematic review

Exercise tests are often used to evaluate the functional status of patients with COPD. However, to the best of our knowledge, a comprehensive systematic comparison of these tests has not been performed. We systematically reviewed studies reporting the repeatability and/or reproducibility of these tests, and studies comparing their sensitivity to therapeutic intervention. A systematic review identified primary manuscripts in English reporting relevant data on the following exercise tests: 6-minute walk test (6MWT) and 12-minute walk test, incremental and endurance shuttle walk tests (ISWT and ESWT, respectively), incremental and endurance cycle ergometer tests, and incremental and endurance treadmill tests. We identified 71 relevant studies. Good repeatability (for the 6MWT and ESWT) and reproducibility (for the 6MWT, 12-minute walk test, ISWT, ESWT, and incremental cycle ergometer test) were reported by most studies assessing these tests, providing patients were familiarized with them beforehand. The 6MWT, ISWT, and particularly the ESWT were reported to be sensitive to therapeutic intervention. Protocol variations (eg, track layout or supplemental oxygen use) affected performance significantly in several studies. This review shows that while the validity of several tests has been established, for others further study is required. Future work will assess the link between these tests, physiological mechanisms, and patient-reported measures.

Effects of an incremental walking test in the gait of individuals with Chronic Obstructive Pulmonary Disease

The objective of this study was to evaluate the functionality of gait and cardiorespiratory parameters in individuals with chronic obstructive pulmonary disease (COPD), before and after a walk test, in order to allow the development of strategies, aimed at maintaining autonomy and preservation of independence. In this study, were included individuals with COPD, aged between 50 to 80 years, and excluded those with orthopedic, neurological and cardiac problems, or any condition that would prevent the assessments proposed in this study. The variables measured were:1st peak force, mid peak low and 2nd peak force, time of 1st double support, the swing moment and 2nd double support; single support time, stride length and stride, speed and time gait cycle, heart rate, oxygen saturation and dyspnea/tiredness score, pre and post-test. The sample consisted of 14 individuals (8 females and 6 males), mean age 65.21±9.42 years. In the post-test patients had greater sensation of dyspnea / fatigue, increased speed and reduced time of the gait cycle, increase the 1st peak force and reduction of the mid peak low, reduction the time the 1st double support and the time of the 1st peak force. The physical effort had influenced the gait pattern and cardiorespiratory parameters in this group of individuals with COPD.

Suplementação oral de L-carnitina associada ao treinamento físico e muscular respiratório na doença pulmonar obstrutiva crônica: estudo preliminar

Avaliar os efeitos da suplementação oral de L-carnitina associada ao treinamento físico e muscular respiratório na doença pulmonar obstrutiva crônica (DPOC). Participaram 14 voluntários com idade de 65±10,4 anos e diagnóstico clínico de DPOC moderado, classificados de acordo com a espirometria prévia. Os voluntários foram divididos em grupo treino esteira (GTE) e grupo treino muscular respiratório (GTMR). Realizaram o teste de caminhada de seis minutos (TC6'), teste de caminhada com carga progressiva (TCP), avaliação nutricional do índice de massa corpórea (IMC), dose diária recomendada de L-carnitina, pressões inspiratórias (PImáx) e expiratórias máximas (PEmáx). Fizeram 30 min de caminhada em esteira, 3 vezes/semana por 10 semanas, e o GTMR realizou, ainda, 10 min de treinamento muscular inspiratório (Threshold® IMT) e 10 min de treinamento muscular expiratório (Threshold® PEP) à 50% da PImáx e PEmáx ajustados semanalmente. Após 10 semanas, foram reavaliados. No TC6' pré e pós-programa de treinamento físico, as variáveis alteradas foram: distância percorrida (DP), frequência cardíaca (FC) final, pressão arterial sistólica (PAS) final, pressão arterial diastólica (PAD) final e Borg final no GTMR, no GTE as variáveis alteradas foram FC repouso, FC final, PAS final, Borg repouso e DP. Comparando os grupos no TC6, o GTE apresentou FC final, PAD final e Borg final maiores do que o GTMR na reavaliação; já no TCP, a FC final, PAS final, Borg final foram maiores no GTE, e DP foi maior no GTMR. Na avaliação respiratória, a PEmáx foi maior no GTMR na reavaliação. O treino aeróbio e suplementação de L-carnitina na DPOC otimizou a performance, a capacidade física e a tolerância ao esforço.

Comparação das variáveis fisiológicas no teste de caminhada de seis minutos e no teste da escada em portadores de doença pulmonar obstrutiva crônica

INTRODUÇÃO: A intolerância ao exercício prejudica a realização das atividades de vida diária em portadores de doença pulmonar obstrutiva crônica (DPOC) e a avaliação dessa limitação é fundamental. Objetivo: Comparar o teste de caminhada dos seis minutos (TC6') com o teste da escada (TE) em portadores de DPOC. MÉTODOS: Prospectivo composto por 21 pacientes portadores de DPOC avaliados para um programa de reabilitação pulmonar que realizaram o TC6' e o TE. As variáveis fisiológicas frequência cardíaca (FC) e saturação periférica de oxigênio (SpO2), além da escala de Borg modificada, foram aferidas antes e após cada teste. A distância percorrida era medida ao término de ambos os testes. RESULTADOS: Comparando os momentos (inicial versus final) das variáveis fisiológicas de ambos os testes, foi observado no TC6' (FC 81,1 ± 2,6 versus 98,4 ± 4,4; SpO2 94,9 ± 2,2 versus 90,4 ± 5,0; PSE Borg 0,5 ± 0,8 versus 3,6 ± 2,5) e no TE (FC 86,9 ± 18,8 versus 119,3 ± 14,5; SpO2 94,7 ± 2,5 versus 90,1 ± 4,5; PSE Borg 0,2 ± 0,4 versus 7,0 ± 2,3), sendo que todas as variações foram estatisticamente significativas (p < 0,001) em ambos os testes. Quando avaliada a alteração das variáveis em ambos os testes, verificou-se que a SpO2 obteve redução semelhante (p = 0,912), a FC aumentou significativamente mais no TE (p = 0,006), bem como a PSE Borg (p < 0,001). Em relação à distância percorrida, o TC6' permitiu que os participantes percorressem uma distância significativamente maior do que o TE (404m versus 153m; p < 0,001) CONCLUSÃO: Ambos os testes promoveram alterações fisiológicas significativas. Apesar de o TE representar uma distância significativamente menor, a sobrecarga, bem como a percepção de trabalho, foi significativamente maior.

Avaliação do desempenho físico e funcional respiratório em obesos

INTRODUÇÃO: O desempenho físico tem se tornado importante objeto de estudo em obesos para a avaliação pré-operatória de cirurgia bariátrica. Contudo, ainda há escassez de estudos, especialmente, no que se refere aos testes de campo ou de capacidade funcional. OBJETIVO: comparar os resultados do Teste de Caminhada de seis Minutos (TC6') com os do Shuttle Walk Test (SWT) em mulheres obesas, juntamente com as respostas do questionário HAQ-20. METODOLOGIA: avaliaram-se 13 mulheres, com idade média de 44 ± 11 anos e com Índice de Massa Corpórea (IMC) 43 ± 5 kg/m², submetidas, aleatoriamente e de forma consecutiva, a TC6', SWT, espirometria, força muscular respiratória e questionário HAQ-20. RESULTADOS: Constatou-se que as distâncias apresentaram-se significativamente diferentes (TC6' = 489 ± 129 m e SWT = 244 ± 161 m), sendo que o score do HAQ-20 apresentou uma mediana de 1,125. Quando verificada a correlação do HAQ-20 com TC6' e o SWT, esta foi constatada apenas para o domínio vestir-se com os resultados do TC6. CONCLUSÃO: Com base nesses resultados, conclui-se que a distância percorrida no TC6' foi maior que no SWT, o que sugere melhor aplicabilidade do TC6' em obesos, sendo, nesse caso, possivelmente mais sensível na avaliação da capacidade funcional que o SWT. Os resultados do HAQ-20 foram pouco discriminadores, pois um domínio entre oito mostrou-se significativo quando correlacionado com as distâncias percorridas.

Influência do treinamento da musculatura respiratória e de membros inferiores no desempenho funcional de indivíduos com DPOC

A doença pulmonar obstrutiva crônica (DPOC) caracteriza-se pela obstrução ou limitação crônica do fluxo aéreo, gerando uma desvantagem mecânica, causando fraqueza muscular e recrutamento da musculatura inspiratória acessória. A disfunção muscular esquelética é uma importante manifestação extrapulmonar, que leva à diminuição da capacidade funcional. O objetivo do estudo foi verificar a eficácia de um treinamento da musculatura respiratória e de quadríceps no desempenho funcional de indivíduos com DPOC. De nove indivíduos com idades entre 49 e 76 anos foram avaliadas as pressões respiratórias máximas (por manovacuometria), força muscular de membros inferiores (por repetição máxima), capacidade funcional (pelo teste de caminhada com carga progressiva, shuttle test) e qualidade de vida (pelo questionário de qualidade de vida SF-36), antes e depois da aplicação de protocolo de fortalecimento da musculatura inspiratória, dos músculos quadríceps e abdominais. As sessões de exercícios foram realizadas duas vezes por semana durante dois meses. Foi verificada melhora em todas as variáveis avaliadas, com diferença significativa na pressão inspiratória máxima (p<0,05). O treinamento da musculatura respiratória e de quadríceps proposto mostrou-se benéfico ao desempenho funcional de indivíduos com DPOC, sugerindo a utilização do fortalecimento muscular respiratório e periférico como recurso coadjuvante no tratamento desses indivíduos.

An original field evaluation test for chronic obstructive pulmonary disease population: the six-minute stepper test

PURPOSE

The aim of this study was to evaluate a new field test, the six-minute stepper test (6-MST), by studying its reproducibility, sensitivity and validity.

METHODS

After a familiarization test, 16 patients with chronic obstructive pulmonary disease (COPD) and 15 healthy subjects performed two six-minute stepper tests per day over three evaluation days. Ten of the 16 patients with COPD also performed a six-minute walking test (6-MWT) with an analysis of gas exchange to compare the metabolic requirements of the two tests. Dyspnoea Borg values were evaluated with Borg's CR-10 scale.

RESULTS

The mean (SD) scores for the COPD group for the first and second six-minute stepper tests were 382.49 (106.01) and 412.45 (118.39) strokes/6 minutes, respectively. Crossed comparison between the first or the second six-minute stepper tests of each evaluation day revealed no significant difference, indicating the reproducibility of the test. The sensitivity was demonstrated by a significantly higher performance in the healthy group (P < 0.001), demonstrating the ability of the test to detect two groups with different fitness levels. Finally, mean dyspnoea Borg values (SD) were significantly lower (P < 0.05) during the six-minute stepper test than during 6-MWT (2.5 (1.5) versus 3.1 (1.2)).

CONCLUSIONS

This study demonstrated that the six-minute stepper test is a reproducible, sensitive, secure, well-tolerated and feasible test for patients with COPD. The reproducibility and sensitivity of the six-minute stepper test suggests that this test could be used in the evaluation of exercise tolerance in patients with COPD.