Juliano Ferreira Arcuri

Reproducibility of Cadence-Free 6-Minute Step Test in Subjects with COPD

BACKGROUND: Six-minute step test (6MST) has been used to assess functional capacity in chronic conditions; however, its reproducibility in the COPD population has not been evaluated. Our study objective was to evaluate 6MST reproducibility. METHODS: The test was performed in a single 20-cm height step, and subjects were instructed to step up and down (cadence-free) for 6 min. Subjects underwent three tests. The first and second were controlled by the same assessor with a 30-min interval. The third test was controlled by a different assessor one week later. For intra-rater comparison, the first and second performances of the test were used, and for inter-assessor comparison, the better performance of the first two tests was compared with the third test. RESULTS: Excellent intra-rater and inter-rater relative reproducibility was observed (intraclass correlation coefficient > 0.8), and there was no statistical difference (repeated measures of analysis of variance) among the performances of the three tests. Intra-rater error values were acceptable (mean error of 5.7 steps and limits of agreement between −7 and 18 steps). Inter-rater error values were not acceptable (mean error of 4.4 steps and limits of agreement between −20 and 29 steps. CONCLUSIONS: 6MST proved to be reproducible in the COPD population when performed by the same assessor.

Validity of the six-minute step test of free cadence in patients with chronic obstructive pulmonary disease

Objectives: to evaluate the concurrent validity of the six-minute step test (6MST) in assessing exercise capacity of COPD patients using the six-minute walk test (6MWT) as a gold-standard. The predictive validity of the 6MST was assessed to determine a cut-off point for identification of low exercise capacity. Method: thirty-two COPD patients (50-87 years old) with mild to very severe obstruction performed the 6MST and 6MWT twice. Results: Concurrent validity: a strong positive correlation (Pearson) between the number of ascents on the first (T1), second (T2) and the best of both (T1 or T2) tests during the 6MWT was observed. Although a moderate negative correlation with BODE index and FEV1 was found, it was considered insufficient to test the validity, therefore ROC curves were not applied. The predictive validity (ROC) of the 6MST to identify low physical capacity (compared with the 6MWT) using the performance of T1 or T2, or solely T1 was considered accurate, and the area under the curve was 0.8 (IC95% 0.62-0.98) and 0.85 (IC95% 0.70-0.99), respectively. To classify patients, the cut-off points of 86 and 78 steps were chosen, with both values showing 90% of sensitivity and specificity of 64% and 68% for T1 or T2, or solely T1, respectively. Conclusion: The number of steps on the 6MST was valid to verify exercise capacity in COPD patients and the cut-off point of 78 steps was able to identify patients with poor exercise tolerance. Values under this cut-off point are considered to identify patients with a poorer prognosis.

Validity and Reliability of the 6-Minute Step Test in Healthy Individuals: A Cross-sectional Study.

Objective:To determine the 6-minute step tests (6MST) reliability and validity and to establish reference performance values of this test. Design:Prospective observational cross-sectional study. Setting:Spirometry and Respiratory Physiotherapy Laboratory, Federal University of São Carlos (institutional). Participants:Ninety-one individuals [42 men and 49 women, mean age = 39 years (SD, 17 years)] without any diagnosed diseases and with normal exercise capacity [6-minute walk test (6MWT) >75% of the predicted normal]. Independent Variables:Participants underwent two 6MST on 1 day and two 6MWT on another day in randomized order. Furthermore, age, gender, height, weight, lower limbs length, abdominal circumference, percentage of body fat, and fat-free mass were obtained. Main Outcome Measures:Test–retest reliability was assessed by comparing the findings of the two 6MST using the intraclass correlation coefficient (ICC) and Bland–Altman plot. Validity was assessed by comparing outcomes of the 6MST to outcomes of 6MWT using the Pearson correlation coefficient. A multiple regression analysis was conducted using the stepwise method to develop an equation to predict reference values. Results:The performance (mean steps ± SD) in the first and second test was 149 ± 34 and 149 ± 36 steps, respectively, which was correlated to distance (in meters) in 6MWT (r = 0.72; P < 0.05). Six-minute step test performance was reliable (ICC = 0.9; 95% confidence interval: 0.85–0.93). The equation to predict reference values for the first 6MST was significant (P < 0.001 and R2 = 0.48): Performance(steps) = 174 to 1.05 × Age(years) to women and Performance(steps) = 209 to 1.05 × Age(years) to men. Conclusions:Six-minute step test is a reliable and valid test. Moreover, the number of steps may be predicted by demographic and anthropometric variables with moderate strength of prediction. Clinical Relevance:Six-minute step test is an exercise test that is easy to be conducted, more tolerable than a graded exercise test, requires fewer equipments and space, and permits better monitoring of the participants. The assessment of the reliability, validity, and reference values will provide a better interpretability for clinicians to use it, especially in primary care.

Should the 6-Minute Walk Test Be Compared When Conducted by 2 Different Assessors in Subjects With COPD?

BACKGROUND: The 6-min walk test (6MWT) is an important tool in the assessment of functional capacity and prognosis in patients with COPD. However, especially in long-term follow-up in clinical settings, this test may be executed by a different assessor, and it is not well known whether 6MWT has an acceptable inter-rater reliability. The aim of this study is to analyze the intra- and inter-rater reliability of the performance in 6MWT, its cardiorespiratory changes, and effort perception in subjects with COPD. METHODS: Thirty-two subjects with a diagnosis of COPD participated in the study, but 3 subjects did not appear on the second day of evaluation and therefore were included only in the intra-rater analysis; the first and second tests were executed by the same assessor with a 30-min interval between them, and the last was executed by a different assessor a week later. The intra-rater reliability was verified comparing the first and second 6MWT performance, and the inter-rater reliability was verified comparing the third test with the best performance of the first and second tests. RESULTS: The intraclass correlation coefficient values were >0.75 (P < .001) for the walked distance on the 6MWT; however, the limits of agreement, SE of measurement, and minimal detectable difference were higher than the minimum clinically important differences already mentioned in the literature (∼25, 26, and 54 m), and the coefficient of variation was small in both intra- and inter-rater comparisons. CONCLUSIONS: The 6MWT showed excellent reliability for distance and perceived exertion and moderate to excellent for HR and SD as assessed by intra- and inter-rater analysis. Thus, based on the main study outcomes, we concluded that the 6MWT can be compared when conducted by 2 different evaluators.

Benefits of interventions for respiratory secretion management in adult palliative care patients—a systematic review

BackgroundRespiratory secretions impact negatively on palliative patients. Unfortunately, a gold standard therapy is not yet available. The purpose of this study was to identify which interventions are in use to control respiratory secretions in patients with chronic disease with a poor prognosis and verify their effects on outcomes relevant for palliative care patients.MethodsA systematic review of the literature with narrative summary was conducted. We searched eight electronic databases in April 6th, 2016. Citation-tracking and reference list searches were conducted. We included randomized controlled trials, crossover trials, observational and qualitative studies regarding interventions for respiratory secretion management in adult patients with chronic diseases that met inclusion criteria indicating short prognosis.ResultsSix randomized controlled trials, 11 observational studies, ten crossover trials and one qualitative study were found. Interventions included mechanical insufflation-exsufflation (MIE), expiratory muscle training, manually-assisted cough, tracheotomy, chest physiotherapy, suctioning, air stacking, electrical stimulation of abdominal muscles, nebulized saline, positive expiratory pressure masks, percussive ventilation, high frequency chest wall oscillations. The interventions with most promising benefits to patients in palliative care were manually-assisted cough and mechanical insufflation-exsufflation to promote expectoration and percussive ventilation to improve mucous clearance.ConclusionTherapies, such as manually assisted cough, mechanical insufflation-exsufflation and percussive ventilation, which aim to deal with respiratory secretion, were the most promising treatment for use in palliative care for specific diseases. Nevertheless, the evidence still needs to improve in order to identify which treatment is the best.

Exacerbation and functional capacity of patients with COPD undergoing an exercise training program: longitudinal study

Objective To analyze if there is influence of body weight, body mass index (BMI), body composition, dyspnoea, grip strength and tolerance to exertion in the occurrence of exacerbation during a 12-month follow up of patients with COPD who underwent a physical training program. Material and methods Sixty three patients were distributed in two groups, (Exacerbation Group — EG, n = 29; Non-Exacerbated Group — NEG, n = 34). The Mann Whitney test was used for the comparison between groups, the Friedman test (posthoc Dunn) to compare the assessments and the logistic regression analysis, with a significance level of p < 0.05. Results There is a significant difference between the groups in age and walked distance (WD) in the sixminute walk test (6MWT). The WD was reduced in 6th, 9th and 12th month revaluation compared to baseline and 3 months for the EG. Logistic regression analysis showed a significant interaction between the lean body mass and the WD, BMI with the lean body mass and the BMI with the WD, this and the isolated dyspnoea, and lean body mass with body weight. Conclusion Involving several variables along the follow up of patients with COPD in physical therapy programs is important, since it may prevent or reduce the chance of the occurrence of exacerbations. In addition, older patients with less tolerance to physical activity had a higher number of episodes of exacerbation, even when participating in a physiotherapy program associated to exercise training.

Reproductibilidad del test de caminata y del escalón de 6 minutos en adultos jóvenes saludables

INTRODUCAO: Os testes caminhada de seis minutos (TC6) e degrau de seis minutos (TD6) sao meios de avaliacao da capacidade funcional. No entanto, pouco se sabe sobre sua reprodutibilidade em adultos jovens.OBJETIVO: Avaliar a reprodutibilidade relativa e absoluta tanto intra quanto inter-avaliadores do TC6 e TD6 em individuos adultos jovens.METODOS: Foram avaliados 33 individuos adultos jovens aparentemente saudaveis por meio da espirometria; e realizados os testes TC6 e TD6. Tres (T1, T2 e T3) TC6 e TD6 foram feitos em cada individuo, sendo o ultimo de cada teste realizado por um avaliador diferente. Para a analise intra-avaliadores foram comparados os desempenhos do T1 e T2 enquanto que a analise inter-avaliadores foi feita pela comparacao dos desempenhos do T3 com: T1; T2; e escolha do melhor dos primeiros dois testes. Foi calculado o coeficiente de correlacao intra-classe (CCI) como medida da reprodutibilidade relativa; o erro padrao de medida; a diferenca minima detectavel; tracados graficos de Bland-Altman e teste ANOVA para analisar a reprodutibilidade absoluta.RESULTADOS: Observaram-se, nos dois testes funcionais, intra e inter-avaliadores, valores excelentes de reprodutibilidade relativa (CCI>0,75) e a reprodutibilidade absoluta mostrou alto erro.CONCLUSAO: O TD6 e o TC6 apresentaram reprodutibilidade intra e inter-avaliadores excelente para a populacao adulto jovem, mas altos valores de erro.Introduction: Six Minute Walk Test (6MWT) and Six Minute Step Test (6MST) are tests to evaluate functional capacity. However, reproducibility of these tests is still not well known in young adults. Objective: To evaluate intra and inter-rater relative and absolute reproducibility of 6MWT and 6MST in young adults. Methods: Thirty-three apparently health young adults were evaluated through spirometry, 6MWT and 6MST. Three (T1, T2 and T3) of each 6MWT and 6MST were carried out on each individual, the latter (T3) by a different evaluator. Intra-rater analysis was performed comparing the performance of T1 and T2, while the inter-rater analysis was executed using the comparisons of T3 with T1, T2 and the best result of the first two. Intra-class correlation coefficient (ICC) was calculated as a measure of relative reproducibility; the standard error of measurement, minimal detectable change, Bland-Altman plots and repeated measures ANOVA were used to verify absolute reproducibility. Results: Excellent values of relative reproducibility (ICC>0.75) were observed in both 6MWT and 6MST, yet high error values were found in absolute reproducibility analysis. Conclusion: 6MWT and 6MST present excellent intra and inter-rater relative reproducibility, but high error values.

Reproducibility of the six-minute walk and step tests in healthy young adults

INTRODUCAO: Os testes caminhada de seis minutos (TC6) e degrau de seis minutos (TD6) sao meios de avaliacao da capacidade funcional. No entanto, pouco se sabe sobre sua reprodutibilidade em adultos jovens.OBJETIVO: Avaliar a reprodutibilidade relativa e absoluta tanto intra quanto inter-avaliadores do TC6 e TD6 em individuos adultos jovens.METODOS: Foram avaliados 33 individuos adultos jovens aparentemente saudaveis por meio da espirometria; e realizados os testes TC6 e TD6. Tres (T1, T2 e T3) TC6 e TD6 foram feitos em cada individuo, sendo o ultimo de cada teste realizado por um avaliador diferente. Para a analise intra-avaliadores foram comparados os desempenhos do T1 e T2 enquanto que a analise inter-avaliadores foi feita pela comparacao dos desempenhos do T3 com: T1; T2; e escolha do melhor dos primeiros dois testes. Foi calculado o coeficiente de correlacao intra-classe (CCI) como medida da reprodutibilidade relativa; o erro padrao de medida; a diferenca minima detectavel; tracados graficos de Bland-Altman e teste ANOVA para analisar a reprodutibilidade absoluta.RESULTADOS: Observaram-se, nos dois testes funcionais, intra e inter-avaliadores, valores excelentes de reprodutibilidade relativa (CCI>0,75) e a reprodutibilidade absoluta mostrou alto erro.CONCLUSAO: O TD6 e o TC6 apresentaram reprodutibilidade intra e inter-avaliadores excelente para a populacao adulto jovem, mas altos valores de erro.Introduction: Six Minute Walk Test (6MWT) and Six Minute Step Test (6MST) are tests to evaluate functional capacity. However, reproducibility of these tests is still not well known in young adults. Objective: To evaluate intra and inter-rater relative and absolute reproducibility of 6MWT and 6MST in young adults. Methods: Thirty-three apparently health young adults were evaluated through spirometry, 6MWT and 6MST. Three (T1, T2 and T3) of each 6MWT and 6MST were carried out on each individual, the latter (T3) by a different evaluator. Intra-rater analysis was performed comparing the performance of T1 and T2, while the inter-rater analysis was executed using the comparisons of T3 with T1, T2 and the best result of the first two. Intra-class correlation coefficient (ICC) was calculated as a measure of relative reproducibility; the standard error of measurement, minimal detectable change, Bland-Altman plots and repeated measures ANOVA were used to verify absolute reproducibility. Results: Excellent values of relative reproducibility (ICC>0.75) were observed in both 6MWT and 6MST, yet high error values were found in absolute reproducibility analysis. Conclusion: 6MWT and 6MST present excellent intra and inter-rater relative reproducibility, but high error values.

Reprodutibilidade do teste de caminhada e do degrau de 6 minutos em adultos jovens saudáveis

INTRODUCAO: Os testes caminhada de seis minutos (TC6) e degrau de seis minutos (TD6) sao meios de avaliacao da capacidade funcional. No entanto, pouco se sabe sobre sua reprodutibilidade em adultos jovens.OBJETIVO: Avaliar a reprodutibilidade relativa e absoluta tanto intra quanto inter-avaliadores do TC6 e TD6 em individuos adultos jovens.METODOS: Foram avaliados 33 individuos adultos jovens aparentemente saudaveis por meio da espirometria; e realizados os testes TC6 e TD6. Tres (T1, T2 e T3) TC6 e TD6 foram feitos em cada individuo, sendo o ultimo de cada teste realizado por um avaliador diferente. Para a analise intra-avaliadores foram comparados os desempenhos do T1 e T2 enquanto que a analise inter-avaliadores foi feita pela comparacao dos desempenhos do T3 com: T1; T2; e escolha do melhor dos primeiros dois testes. Foi calculado o coeficiente de correlacao intra-classe (CCI) como medida da reprodutibilidade relativa; o erro padrao de medida; a diferenca minima detectavel; tracados graficos de Bland-Altman e teste ANOVA para analisar a reprodutibilidade absoluta.RESULTADOS: Observaram-se, nos dois testes funcionais, intra e inter-avaliadores, valores excelentes de reprodutibilidade relativa (CCI>0,75) e a reprodutibilidade absoluta mostrou alto erro.CONCLUSAO: O TD6 e o TC6 apresentaram reprodutibilidade intra e inter-avaliadores excelente para a populacao adulto jovem, mas altos valores de erro.Introduction: Six Minute Walk Test (6MWT) and Six Minute Step Test (6MST) are tests to evaluate functional capacity. However, reproducibility of these tests is still not well known in young adults. Objective: To evaluate intra and inter-rater relative and absolute reproducibility of 6MWT and 6MST in young adults. Methods: Thirty-three apparently health young adults were evaluated through spirometry, 6MWT and 6MST. Three (T1, T2 and T3) of each 6MWT and 6MST were carried out on each individual, the latter (T3) by a different evaluator. Intra-rater analysis was performed comparing the performance of T1 and T2, while the inter-rater analysis was executed using the comparisons of T3 with T1, T2 and the best result of the first two. Intra-class correlation coefficient (ICC) was calculated as a measure of relative reproducibility; the standard error of measurement, minimal detectable change, Bland-Altman plots and repeated measures ANOVA were used to verify absolute reproducibility. Results: Excellent values of relative reproducibility (ICC>0.75) were observed in both 6MWT and 6MST, yet high error values were found in absolute reproducibility analysis. Conclusion: 6MWT and 6MST present excellent intra and inter-rater relative reproducibility, but high error values.

Influência da força muscular isométrica de membros inferiores sobre equilíbrio e índice BODE em pacientes com DPOC: estudo transversal

Introducao Forca muscular de membros inferiores (MMII) diminuida associa-se a limitacao da capacidade funcional; entretanto, existem poucas evidencias sobre a repercussao direta da fraqueza muscular periferica sobre tarefas de equilibrio, bem como com o prognostico de mortalidade nos pacientes com doenca pulmonar obstrutiva cronica (DPOC). Objetivos Verificar se ha relacao da forca isometrica de MMII com Indice BODE e equilibrio funcional de pacientes com DPOC em reabilitacao pulmonar (RP), alem de investigar se esses pacientes apresentam fraqueza muscular, e se tal caracteristica e capaz de influenciar nessas variaveis. Materiais e metodos Trata-se de um estudo transversal, onde avaliou-se 24 pacientes (idade > 50 anos) de ambos os generos, com DPOC moderada a muito grave (VEF1 = 44 (31 - 62,8)% previsto), por meio de:modified Medical Research Council (mMRC), Teste de Caminhada de 6 minutos (TC6), Indice BODE, TesteTimed “Up and Go” (TUG), Escala de Equilibrio de Berg (EEB),Dynamic Gait Index (DGI) e Teste de Forca Isometrica de Extensores de Joelho (ExtJ) e Abdutores de Quadril (AbdQ). Resultados Na amostra estudada, 54% dos pacientes apresentaram fraqueza muscular em ExtJ, com correlacoes moderadas da forca de MMII com Indice BODE (AbdQ = -0,58) e mMRC (ExtJ = -0,48; AbdQ = -0,49). Foram encontradas diferencas para DPTC6 e mMRC quando a forca dos ExtJ foi classificada em normal ou diminuida. Conclusao A forca de AbdQ esta associada ao prognostico de mortalidade e a forca de MMII esta associada a sintomatologia em pacientes com DPOC em RP. Embora a forca de MMII apresente impacto negativo na capacidade funcional e na dispneia, os pacientes desse estudo mantiveram preservado o equilibrio e mobilidade funcional.