Adaptação cardiovascular no Teste de Caminhada dos Seis Minutos em pacientes com DPOC: estudo transversal / Cardiovascular adaptation in the six-minute walk test in COPD patients: transversal study

OBJETIVO: Avaliar o comportamento da adaptação cardiovascular e da saturação periférica de oxigênio em indivíduos com DPOC submetidos no teste de caminhada dos seis minutos (TC6). MATERIAL E MÉTODOS: Trata-se de um estudo de corte transversal, que foram incluídas pessoas com diagnóstico de DPOC, confirmado pela espirometria e de ambos os sexos. A magnitude de sintomas foi avaliada pela escala de dispneia Medical Research Council (MRC) e questionário COPD Assessment Test (CAT). Aplicou-se o TC6 para avaliar a tolerância ao esforço. Para mensurar a frequência cardíaca máxima (FC máx) prevista para a idade foram utilizadas equações específicas para população brasileira. RESULTADOS: Avaliou-se 34 indivíduos com DPOC, 20 (58,8%) homens; relação VEF1/CVF foi 56,7%± 10,2% pós broncodilatador (BD). Quatorze 14 (41,2%) indivíduos apresentaram impacto clínico moderado; 16 (47,2%) dos avaliados apresentou grau 2 na escala do MRC. As médias das distâncias percorridas no primeiro e segundo TC6 foram 383,5 ± 13,6; 408,6 ± 85,7 metros, correspondendo a 70, 75%; 75,10% em relação ao valor previsto (p=0,001). As médias da FC máx ao final do primeiro e segundo TC6, foram 94,1 ± 21,9; 92,3 ± 17,9 bpm e a FC pós percentual da FC máx prevista pré e pós TC6 foram 61,1% ± 17,7%; 59,7% ± 21,5% e 14 (41,2%) pacientes apresentaram dessaturação de O2 no primeiro TC6; 9 (26,5%) no segundo teste. CONCLUSÕES: Pacientes com DPOC, apresentam aumento da FC identificado pelo esforço submáximo, por meio do percentual da FC max. Indivíduos com maior comprometimento da função pulmonar apresentaram dessaturação de O2. .

OBJECTIVE: To evaluate the behavior of cardiovascular adaptation and peripheral oxygen saturation in individuals with COPD submitted to the six-minute walk test (6MWT). MATERIAL AND METHODS: It was performed a descriptive study with person with a diagnosis of COPD confirmed by spirometry of both sexes. The Medical Research Council (MRC) dyspnea scale and the COPD Assessment Test (CAT) questionnaire were used to assess the magnitude of symptoms. The 6MWT was used to assess effort tolerance. To measure the maximum heart rate (HRmax) predicted for age, specific equations were used for the Brazilian population. RESULTS: 34 individuals with COPD were evaluated, 20 (58.8%) men; FEV1 / FVC ratio was 56.7% ± 10.2% after BD. Fourteen (41.2%) were classified as grade 2 and were classified as grade 2 (MRC scale). The means of the distances covered in the first and second TC6 were 383.5 ± 13.6; 408.6 ± 85.7 meters, corresponding to 70.7%; 75.1% in relation to the predicted value (p = 0.001). The mean maximum heart rate at the end of the first and second 6MWT were 94.1 ± 21.9; 92.3 ± 17.9 bpm and the heart rate post-percentage of the predicted maximum heart rate before and after the 6MWT were 61.1% ± 17.7%; 59.7% ± 21.5% and 14 (41.2%) patients presented O2 desaturation on the 6MWT; 9 (26.5%) in the second test. CONCLUSIONS: Patients with COPD throughout the 6MWT show increased heart rate and O2 desaturation in exercise activity.

Relationship between gait speed and physical function in patients with symptomatic peripheral artery disease

OBJECTIVE: The aim of the study was to analyze the relationship between gait speed and measurements of physical function in patients with symptomatic peripheral artery disease (PAD). METHODS: One hundred sixty-nine patients (age 66.6±9.4 years) with symptomatic PAD were recruited. Usual and fast gait speeds were assessed with a 4-meter walk test. Objective (balance, sit-to-stand, handrip strength, and six-minute walk test) and subjective (WIQ - Walking Impairment Questionnaire and WELCH - Walking Estimated-Limitation Calculated by History) measurements of physical function were obtained. Crude and adjusted linear regression analyses were used to confirm significant associations. RESULTS: Usual and fast gait speeds were significantly correlated with all objective and subjective physical function variables examined (r<0.55, p<0.05). In the multivariate model, usual gait speed was associated with six-minute walking distance (β=0.001, p<0.001), sit-to-stand test score (β=-0.005, p=0.012), and WIQ stairs score (β=0.002, p=0.006) adjusted by age, ankle brachial index, body mass index, and gender. Fast gait speed was associated with six-minute walking distance (β=0.002, p<0.001), WIQ stairs score (β=0.003, p=0.010), and WELCH total score (β=0.004, p=0.026) adjusted by age, ankle brachial index, body mass index, and gender. CONCLUSION: Usual and fast gait speeds assessed with the 4-meter test were moderately associated with objective and subjective measurements of physical function in symptomatic PAD patients.

Alternatives to Aerobic Exercise Prescription in Patients with Chronic Heart Failure / Alternativas para Prescrição de Exercício Aeróbio a Pacientes com Insuficiência Cardíaca

Background: Exercise is essential for patients with heart failure as it leads to a reduction in morbidity and mortality as well as improved functional capacity and oxygen uptake (v̇O2). However, the need for an experienced physiologist and the cost of the exam may render the cardiopulmonary exercise test (CPET) unfeasible. Thus, the six-minute walk test (6MWT) and step test (ST) may be alternatives for exercise prescription. Objective: The aim was to correlate heart rate (HR) during the 6MWT and ST with HR at the anaerobic threshold (HRAT) and peak HR (HRP) obtained on the CPET. Methods: Eighty-three patients (58 ± 11 years) with heart failure (NYHA class II) were included and all subjects had optimized medication for at least 3 months. Evaluations involved CPET (v̇O2, HRAT, HRP), 6MWT (HR6MWT) and ST (HRST). Results: The participants exhibited severe ventricular dysfunction (ejection fraction: 31 ± 7%) and low peak v̇O2 (15.2 ± 3.1 mL.kg-1.min-1). HRP (113 ± 19 bpm) was higher than HRAT (92 ± 14 bpm; p < 0.05) and HR6MWT (94 ± 13 bpm; p < 0.05). No significant difference was found between HRP and HRST. Moreover, a strong correlation was found between HRAT and HR6MWT (r = 0.81; p < 0.0001), and between HRP and HRST (r = 0.89; p < 0.0001). Conclusion: These findings suggest that, in the absence of CPET, exercise prescription can be performed by use of 6MWT and ST, based on HR6MWT and HRST.

Fundamento: O exercício físico é fundamental para pacientes com insuficiência cardíaca, pois reduz a morbimortalidade e melhora a capacidade funcional e o consumo de oxigênio (v̇O2). Entretanto, a realização do teste de exercício cardiopulmonar (TECP) pode se tornar inviável, devido à necessidade de médico capacitado e ao alto custo deste exame. Assim, o teste de caminhada de 6 minutos (TC6M) e o teste do degrau (TD) emergem como alternativas para a prescrição de exercício. Objetivo: Correlacionar a frequência cardíaca (FC) durante o TC6M e o TD com a FC no limiar aeróbio (FCLA) e a FC no pico do exercício (FCP), obtidas no TECP. Métodos: Foram incluídos 83 pacientes (58 ± 11 anos) com insuficiência cardíaca (NYHA classe II), com medicação otimizada por pelo menos 3 meses. Foram realizados TECP (v̇O2, FCLA e FCP), TC6M (FCTC6M) e TD (FCTD). Resultados: Os pacientes apresentavam disfunção ventricular grave (fração de ejeção: 31 ± 7%) e baixo v̇O2 pico (15,2 ± 3,1 ml.kg-1.min-1). A FCP (113 ± 19 bpm) foi maior que a FCLA (92 ± 14 bpm; p < 0,05) e a FCTC6M (94 ± 13 bpm; p < 0,05). Não houve diferença entre FCP e FCTD. Além disso, observou-se forte correlação entre a FCLA e a FCTC6M (r = 0,81; p < 0,0001) e entre a FCP e a FCTD (r = 0,89; p < 0,0001). Conclusão: Os resultados obtidos sugerem ser viável a prescrição de exercício através do TC6M e do TD, com base na FCTC6M e na FCTD, na ausência do TECP.

Avaliação do comprometimento respiratório em pacientes com lúpus eritematoso sistêmico com o teste de caminhada de seis minutos / Evaluation of respiratory impairment in patients with systemic lupus erythematosus with the six-minute walk test

Objetivo: Avaliar pacientes com LES estável, sem comprometimento respiratório evidente, por meio do TC6M. Casuística e métodos: Foram recrutados 45 pacientes com LES estável. Foi utilizado o protocolo ATS/ERS para TC6M, tendo sido escolhidos dois parâmetros com pontos de corte. Resultados: Quarenta e dois dos pacientes eram mulheres.A média de idade foi 39 ± 11,4 anos; a duração média da doença, 121 ± 93,1 meses; valor médio de MRC 2 ± 0; CVF média 85,9 ± 34,2%; VEF1 médio 67,5 ± 21,6%; PIM média 82 ± 58,4%; PEM média 78 ± 37,3%; frequência cardíaca média em repouso 75 ± 12,8 bpm; frequência respiratória média em repouso 19 ± 5,3 bpm; distância média no TC6M 478 ± 82 m; SpO2 média em repouso 98 ± 0,8%; queda média em SpO2 4 ± 6 pontos. Quando a população em estudo foi dividida de acordo com o valor de corte de 400 m de distância caminhada, a frequência cardíaca imediatamente antes do teste foi significativamente menor naqueles participantes que caminharam menos de 400 m (p = 0,0043), da mesma forma que o valor da escala de Borg (p = 0,0036). De acordo com a presença de saturação ≥ 4, a frequência cardíaca ao final do teste estava significativamente mais elevada naqueles participantes exibindo dessaturação (p = 0,0170); PEM (p = 0,0282) e TC6M (p = 0,0291) estavam significativamente menores e PIM revelou uma tendência para diminuir (p = 0,0504). CVF < limite inferior do normal foi achado significativamente associado com o grupo com dessaturação (p = 0,0274). Conclusão: Comparado com TC6M, a dessaturação foi o indicador mais apropriado para localizar os pacientes com os índices mais comprometidos nos testes de função respiratória. .

Objective: Evaluate SLE stable patients, without overt respiratory compromise, by means of 6MWT. Casuistic and methods: Forty-five stable SLE patients were enrolled. The ATS/ERS protocol for 6MWT, was used and two parameters with cut-off points were chosen. Results: Forty-two patients were women. The mean age was 39 ± 11.4 years; mean duration of disease, 121 ± 93.1 months; mean value of MRC, 2 ± 0; mean FVC, 85.9 ± 34.2%; mean FEV1, 67.5 ± 21.6%; mean MIP, 82 ± 58.4%; mean MEP, 78 ± 37.3%; mean heart rate at rest, 75 ± 12.8 bpm; mean respiratory rate at rest, 19 ± 5.3 bpm; mean 6MWD, 478 ± 82 m; mean SpO2 at rest was 98 ± 0.8%; mean fall in SpO2, 4 ± 6 points. When the study population was divided according to the 400-m walk distance cut-off value, the heart rate immediately before the test was significant lower in those participants who walked less than 400 m (p = 0.0043), just like the value of Borg scale (p = 0.0036); according to the presence of saturation ≥ 4, heart rate at the end of the test was significantly higher in those participants who were showing desaturation (p = 0.0170); MEP (p = 0.0282) and 6MWD (p = 0.0291) were significantly lower, and MIP showed a tendency towards being smaller (p = 0.0504). FVC < normal inferior limit was significantly associated with the group with desaturation (p = 0.0274). Conclusion: Compared to 6MWD, desaturation was better suited to find the patients with the most compromised indexes in respiratory function tests. .

Diastolic function and functional capacity after a single session of continuous positive airway pressure in patients with compensated heart failure

OBJECTIVE: The effects of acute continuous positive airway pressure therapy on left ventricular diastolic function and functional capacity in patients with compensated systolic heart failure remain unclear. METHODS: This randomized, double-blind, placebo-controlled clinical trial included 43 patients with heart failure and a left ventricular ejection fraction <0.50 who were in functional classes I-III according to the New York Heart Association criteria. Twenty-three patients were assigned to continuous positive airway pressure therapy (10 cmH2O), while 20 patients received placebo with null pressure for 30 minutes. All patients underwent a 6-minute walk test (6MWT) and Doppler echocardiography before and immediately after intervention. Clinicaltrials.gov: NCT01088854. RESULTS: The groups had similar clinical and echocardiographic baseline variables. Variation in the diastolic function index (e′) after intervention was associated with differences in the distance walked in both groups. However, in the continuous positive airway pressure group, this difference was greater (continuous positive airway pressure group: Δ6MWT = 9.44+16.05×Δe′, p = 0.002; sham group: Δ6MWT = 7.49+5.38×Δe′; p = 0.015). There was a statistically significant interaction between e′ index variation and continuous positive airway pressure for the improvement of functional capacity (p = 0.020). CONCLUSIONS: Continuous positive airway pressure does not acurately change the echocardiographic indexes of left ventricle systolic or diastolic function in patients with compensated systolic heart failure. However, 30-minute continuous positive airway pressure therapy appears to have an effect on left ventricular diastolic function by increasing functional capacity. .

Diastolic function is associated with quality of life and exercise capacity in stable heart failure patients with reduced ejection fraction

Exercise capacity and quality of life (QOL) are important outcome predictors in patients with systolic heart failure (HF), independent of left ventricular (LV) ejection fraction (LVEF). LV diastolic function has been shown to be a better predictor of aerobic exercise capacity in patients with systolic dysfunction and a New York Heart Association (NYHA) classification ≥II. We hypothesized that the currently used index of diastolic function E/e' is associated with exercise capacity and QOL, even in optimally treated HF patients with reduced LVEF. This prospective study included 44 consecutive patients aged 55±11 years (27 men and 17 women), with LVEF<0.50 and NYHA functional class I-III, receiving optimal pharmacological treatment and in a stable clinical condition, as shown by the absence of dyspnea exacerbation for at least 3 months. All patients had conventional transthoracic echocardiography and answered the Minnesota Living with HF Questionnaire, followed by the 6-min walk test (6MWT). In a multivariable model with 6MWT as the dependent variable, age and E/e' explained 27% of the walked distance in 6MWT (P=0.002; multivariate regression analysis). No association was found between walk distance and LVEF or mitral annulus systolic velocity. Only normalized left atrium volume, a sensitive index of diastolic function, was associated with decreased QOL. Despite the small number of patients included, this study offers evidence that diastolic function is associated with physical capacity and QOL and should be considered along with ejection fraction in patients with compensated systolic HF.

Body composition, muscle strength and quality of active elderly women according to the distance covered in the 6-minute walk test

BACKGROUND: Changes arising from the aging process, particularly changes in body composition, contribute to the functional decline of the elderly. OBJECTIVE: To compare the body composition and muscle strength, mobility and quality in active elderly women according to the distance walked during the 6-minute walk test (6MWT). METHOD: The study included 77 active elderly women aged 65 to 80 years, who were divided into tertiles (A, B and C) according to the distance covered in the 6MWT. We performed anthropometric and clinical evaluations. Body composition was determined by dual energy X-ray absorptiometry (DXA). Handgrip strength (HGS) was measured with a portable dynamometer (Saehan), and knee extension strength (KES) was measured with the one repetition maximum test (1-RM). Functional mobility was assessed by the Timed Up and Go (TUG) test, and body balance was assessed by the Berg Balance Scale (BBS). Muscle quality was defined by the ratio between muscle strength (kgf) and muscle mass (kg). RESULTS: The group that walked the shortest distance in the 6MWT had a higher BMI (A=30.8±7.0, B=27.2±4.2 and C=25.9±3.5 kg/m2), greater amount of fat mass (A=31.3±10.7, B=25.9±6.7 and C=23.81±6.46 kg) lower HGS (A=21.8±5.1, B=22.1±3.5 and C=25.5±5.1 kgf), lower knee extension strength (A=30.6±10.9, B=40.4±12.5 and C=47.2±10.1 kgf), lower arm muscle quality (A=10.1±3.7, B=11.6±2 and C=12.7±2.2 kg) and lower leg muscle quality (A=1.78±1, B=2.84±0.98 and C=3.31±0.77 kg). There was no significant difference between muscle mass (p=0.25) and lean mass (p=0.26). CONCLUSION: Body fat has a negative influence on functional performance, even among active elderly women. .

Redução da capacidade funcional e exacerbação da dor durante o esforço do teste de caminhada de 6 minutos em mulheres com fibromialgia / Impaired functional capacity and exacerbation of pain and exertion during the 6-minute walk test in women with fibromyalgia

CONTEXTUALIZAÇÃO: A fibromialgia (FM) parece limitar o desempenho físico, e a realização de atividades da vida diária (AVDs) pode exacerbar a dor e o esforço percebido nesses pacientes. OBJETIVOS: Comparar o desempenho do teste de caminhada de 6 minutos (TC6) entre pacientes com FM e controles e verificar relações entre esse desempenho com o impacto na qualidade de vida, na realização de tarefas da vida diária e no nível de atividade física. MÉTODOS: Participaram do estudo 19 mulheres com FM e 20 mulheres saudáveis. Realizou-se o TC6 e, durante o teste, foram mensuradas a intensidade de dor e a percepção subjetiva de esforço (PSE). Foram aplicados o Fibromyalgia Impact Questionnaire (FIQ), Health Assessment Questionnaire (HAQ) e o International Physical Activity Questionnaire (IPAQ). RESULTADOS: O grupo de mulheres com FM percorreu menor distância no TC6 (pacientes: 473,52±77,84 m versus controles: 541,75±85,62 m; p=0,02). Para o grupo de pacientes houve correlações entre a distância caminhada e o questionário FIQ (r=-0,46; p=0,05), o HAQ (r=-0,49; p=0,03) e o consumo de oxigênio (r=0,78; p<0,01) e entre o HAQ e o consumo de oxigênio (r=-0,52; p=0,02). Durante o teste, as mulheres com FM apresentaram aumento da intensidade dolorosa e da PSE, o que não ocorreu no grupo controle. CONCLUSÕES: Mulheres com FM apresentaram comprometimento da capacidade funcional e exacerbação da dor e esforço durante o TC6.

BACKGROUND: Fibromyalgia has been association with physical performance limitations. Additionally, activities of daily living have been reported to be directly associated with the exacerbation of pain and perceived exertion in this patient population. OBJECTIVES: To compare the performance of a 6-minute walk (6MWT) test in patients with fibromyalgia and controls and to evaluate the relationship between test performance and quality of life, limitations of activities of daily living and physical activity level. METHODS: The study included 19 women with fibromyalgia (FM) and 20 healthy controls (CG). A 6MWT was conducted and pain intensity and perceived effort (PE) were assessed during the test. In addition, Fibromyalgia Impact Questionnaire (FIQ), Health Assessment Questionnaire (HAQ) and International Physical Activity Questionnaire (IPAQ) were applied. RESULTS: The fibromyalgia group walked significantly shorter distances when compared to the control group (FM: 473.52±77.84 m vs. CG: 541.75±85.62 m; p=0.02). In the fibromyalgia group, there was a negative correlation between distance in 6MWT and FIQ (r=-0.46; p=0.05), HAQ (r=-0.49; p=0.03) and oxygen consumption (r=0.78; p<0.01). There was also a correlation between HAQ and oxygen consumption (r=0.52; p=0.02). Participants with fibromyalgia had higher pain intensity and perceived effort during the test when compared to the control group. CONCLUSIONS: Women with fibromyalgia had greater impaired of functional capacity, exacerbation of pain and exertion during the 6MWT when compared to healthy women.

Evaluation of the six-minute walk test in patients with chronic heart failure associated with Chagas' disease and systemic arterial hypertension / Avaliação do teste de caminhada de seis minutos em pacientes com insuficiência cardíaca crônica associada à doença de Chagas e hipertensão arterial sistêmica

INTRODUCTION: To evaluate physical capacity as determined by the six-minute walk test (6MWT) in patients with chronic heart failure due to Chagas' disease associated with systemic arterial hypertension (Chagas-SAH). METHODS: A total of 98 patients routinely followed at the Cardiomyopathy Outpatient Service were recruited. Of these, 60 (61 percent) were diagnosed with Chagas disease and 38 (39 percent) with Chagas-SAH. RESULTS: The distance walked during 6 min was 357.9 ±98 m for Chagas-SAH patients and 395.8 ± 121m for Chagas cardiomyopathy patients (p >0.05). In patients with Chagas-SAH, a negative correlation occurred between the 6MWT and the total score of the Minnesota Living with Heart Failure Questionnaire (r= -0.51; p=0.001). No other correlations were determined between 6MWT values and continuous variables in patients with Chagas-SAH. CONCLUSIONS: The results of the 6MWT in Chagas-SAH patients are similar to those verified in Chagas cardiomyopathy patients with chronic heart failure. Coexistence of SAH does not seem to affect the functional capacity of Chagas cardiomyopathy patients with chronic heart failure.

INTRODUÇÃO: Avaliar a capacidade física medida pelo teste de caminhada de seis minutos em pacientes com insuficiência cardíaca crônica secundária à associação de cardiomiopatia chagásica com hipertensão arterial sistêmica (Chagas-HAS). MÉTODOS: Noventa e oito pacientes rotineiramente tratados no Ambulatório de Cardiomiopatia do Hospital de Base foram utilizados no estudo. Deles, 60 (61 por cento) eram portadores de cardiomiopatia chagásica (ChCM), enquanto 38 (39 por cento) apresentavam a associação Chagas-HAS. RESULTADOS: A distância média caminhada foi de 357,9 ± 98m no grupo Chagas-SAH e 395,8 ± 121m no grupo ChCM (p >0,05). Nos pacientes com Chagas-SAH, houve correlação negativa entre o Teste de Caminhada de 6 Minutos e a somatória de pontos obtida no Questionário Vivendo com a Insuficiência Cardíaca. (r=-0,51; p=0,001). Nenhuma outra correlação foi observada entre o teste de caminhada de seis minutos e as variáveis contínuas examinadas no grupo Chagas-SAH. CONCLUSÕES: Os resultados do teste de caminhada de seis minutos em pacientes com Chagas-SAH são semelhantes aos observados em pacientes com ChCM. A coexistência de HAS parece não afetar a capacidade funcional de pacientes com a associação de cardiomiopatia da doença de Chagas e HAS.

Desaturation - distance ratio: a new concept for a functional assessment of interstitial lung diseases

INTRODUCTION: The functional evaluation has become increasingly important in the understanding and management of patients with interstitial lung diseases. The cardiopulmonary exercise test and the six-minute walk test (6MWT), through their isolated variables, have been used to do this evaluation, with some limitations. OBJECTIVES: We proposed a new composite index (desaturation distance ratio using continuous peripheral oxygen saturation (SpO2) and the distance walked as a more reliable tool for doing a functional evaluation of these patients. METHODS: 6MWT was performed by interstitial lung diseases patients and controls. Analyzed parameters were walked distance and desaturation area (DAO2), obtained by taking the difference between maximal SpO2 possible (100 percent) and patient's SpO2 every 2 seconds. desaturation distance ratio was calculated using the ratio between DAO2 and distance walked. RESULTS: Forty-nine interstitial lung diseases patients and 11 control subjects completed the protocol. The mean (SD) age was 60 (12) years and 65 (9) years, respectively (p:NS). Data obtained from 6MWT showed a significant statistical difference between interstitial lung diseases patients and controls: mean walked distance (430 and 602 meters, respectively); SpO2 minimal maintained at least 10 seconds - SpO2 min (85 percent and 94 percent, respectively), and median desaturation distance ratio (10 and 2.5, respectively). A correlation analysis, considering interstitial lung diseases patients, revealed the best correlation between desaturation distance ratio and DLco (r= - 0.72; p<0.001), being the correlation between SpO2 min and DLco of 0.61 (p<0.001) and among walked distance and DLco of 0.58 (p<0.05). CONCLUSION: Desaturation distance ratio is a promising concept and a more reliable physiologic tool to assess pulmonary diseases characterized by involvement of the alveolar-capillary membrane, such as interstitial lung diseases.

Relationship of BODE Index to functional tests in chronic obstructive pulmonary disease

OBJECTIVE: To determine if there is a correlation between the BODE Index and variables assessed during the Activities of Daily Living assessment, performance on lower limber tests, and peripheral muscle impairment of the upper limb in patients with chronic obstructive pulmonary disease. MATERIALS AND METHODS: Ten men (aged 58 to 80 years old) with moderate to very severe obstruction were evaluated and classified by the BODE Index. They were evaluated by pulmonary ventilation (V•E), oxygen consumption (V•O2), and carbonic gas production (V•CO2) on the ADL assessment; Distance Walking (DW) in the Six Minute Walking Test (6MWT) and the Six Minute Walking Test on Treadmill (6MWTT); number of repetitions in the Sit-to-Stand Test; and the Hand Grip Strength Test. Correlations were evaluated between the classification and the tests performed (Pearson and Spearman test, p<0.05). RESULTS: The mean of the total score for the BODE Index was 2.80 (±1.03), with three patients scoring in the first quartile (Q1) and seven scoring in the second quartile (Q2). This Index showed a negative correlation with the 6MWTT (r=-0.86), the Sit-to-Stand Test (r=-0.66), and the Hand Grip Strength Test (r=-0.83). CONCLUSIONS: Our results show that there is no correlation between the BODE Index and the ventilatory and metabolic responses in the Activities of Daily Living assessment. On the other hand, a correlation was observed between the BODE Index and the variables assessed in the 6MWTT, Sit-to-Stand Test, and Hand Grip Strength Test in moderate to very severe Chronic Obstructive Pulmonary Disease patients. This suggests that these tests can be employed as predictors of physical exercise capacity, perhaps as complementary tests to the BODE Index.

Correlação entre a distância obtida no teste de caminhada de seis minutos e o pico de consumo de oxigênio em pacientes portadores de doença renal crônica em hemodiálise / Correlation between the distance covered in the six-minute walk test with peak oxygen uptake in end-stage renal disease patients on hemodialysis

Introdução: A doença renal crônica (DRC) cursa com importante redução da capacidade funcional. O teste padrão ouro para avaliação da capacidade funcional é o teste cardiopulmonar que determina o pico de consumo de oxigênio (VO2 pico). Por outro lado, o teste de caminhada de seis minutos (TC6M) é um teste representativo das atividades da vida diária, é mais barato e de fácil aplicação. No presente estudo, avaliamos a correlação entre a distância obtida no TC6M e o VO2 pico em pacientes portadores de DRC sob tratamento hemodialítico. Métodos: Foram estudados 16 pacientes portadores de DRC em programa de hemodiálise (cinco homens e 11 mulheres), com média de idade de 47,75 ± 12,05 anos. Os pacientes foram submetidos a dois TC6M emuma pista plana de 30m, com intervalo de 30 minutos, sendo considerada para análise a maior distância percorrida. Para determinação do VO2 pico, ospacientes foram submetidos ao teste cardiopulmonar em esteira rolante. Resultados: A distância média obtida no TC6M foi de 516,0 ± 88,79m e o VO2pico foi 20,50 ± 4,92ml/kg/min. Observamos uma correlação positiva e estatisticamente significante entre a distância obtida no TC6M e o VO2 pico (r =0,78). Conclusão: A forte correlação entre a distância obtida no TC6M e o VO2 pico permite sugerir o TC6M como alternativa simples e barata para avaliação da capacidade funcional de pacientes portadores de DRC em tratamento hemodialítico.

Introduction: End-stage renal disease (ESRD) courses with significant reduction in the functional capacity. The gold standard test for evaluation of the functional capacity is the cardiopulmonary test, which provides the determination of the peak oxygen uptake (VO2 peak). On the other hand, the six-minute walk test (6MWT) is a representative test of the daily living activities, is inexpensive and easily applicable. In this study we aimed to evaluate the correlation between the distance covered in 6MWT with VO2 peak in ESRD patients on hemodialysis. Methods: Sixteen ESRD patients on hemodialysis (five men and11 women) were studied, with a mean age of 47.75 ± 12.05 years. The patients were submitted to two 6MWT in a 30m corridor, with an interval of 30minutes, being considered for analysis longest walked distance. For determination of VO2 peak, the patients were submitted to the cardiopulmonary test on a treadmill. Results: The distance covered in 6MWT was 516.0 ± 88.79m and VO2 peak was 20.50 ± 4.92ml/kg/min. We observed a positive and significant correlation between the distance covered in 6MWT with VO2 peak (r =0.78). Conclusion: The strong correlation between the distance covered in 6MWT with VO2 peak allows us to suggest the 6MWT as a simple and cheap alternative for evaluation of the functional capacity in ESRD patients on hemodialysis.

Avaliação da tolerância ao esforço físico durante o teste de caminhada em esteira em indivíduos com doença oulmonar obstrutiva crônica / Evaluation of the tolerance of physical forces during the walk test in treadmill in individuals with chronic obstructive pulmonary disease

O Teste de Caminhada de 6 Minutos em Esteira (TC6E) tem sido utilizado como um dos testes de avaliação funcional em indivíduos com Doença Pulmonar Obstrutiva Crônica (DPOC). Os objetivos deste estudo foram avaliar a demanda metabólica (VO2/VO2max), ventilatória (VE /VVM), a oxigenação (SpO2) e sensação de dispnéia (SD) durante TC6E, entre indivíduos saudáveis e portadores de DPOC. Foram avaliados 22 homens; 12 com DPOC, Grupo 1 (G1) (VEF1<60% do previsto, 73,5±3,6 anos) e 10 saudáveis, Grupo 2 (G2) (63,3±5,3anos). Para análise do VO2/ VO2max e VE/VVM foi utilizado um sistema metabólico. Na análise intergrupo (Mann-Whitney; p<0,05) em relação a VO2/VO2max constatou-se diferença significativa tanto na situação basal (repouso), como durante o TC6E. Para as variáveis VE/VVM, SpO2 e SD, verificou-se esta diferença apenas na situação basal. Em relação a situação basal e o TC6E para ambos os grupos, observou-se diferença significativa (Wilcoxon, p<0,01) no que se refere a VO2/VO2max e VE/VVM. Para a oxigenação, constatou-se este comportamento apenas para o G1, e em relação a SD, para ambos os grupos. Conclui-se que houve maior demanda metabólica e ventilatória para G1 e que o TC6E caracterizou-se como uma atividade intensa para ambos os grupos; sugerindo a necessidade de melhor fundamentação da metodologia do teste.

The Six Minute Walk Test on Treadmill (6MWT) was used as the functional evaluation in individuals with Chronic Obstructive Pulmonary Disease (COPD). The objectives of this study was to evaluate the Metabolic (VO2/VO2max) and Ventilatory (VE/MVV) Demand, oxygenation and sensation of dyspnea during the 6MWT in healthy individuals and individuals with COPD. 22 males were evaluated, 12 with COPD classified as Group 1 (G1) (FEV1<60%; average age 73.5±6.3), and 10 healthy individuals (average age 63.3±5.3), classified as Group 2 (G2). For analysis between the VO2/VO2max and VE/MVV following the metabolic system. In analysis between groups (Mann-Whitney; p?0.05) in relation the VO2/VO2max there was a significant difference both in basal situation (rest), and during the 6MWT. For the variables VE/MVV, SpO2 and SD, verified difference only in basal situation. In relation to the basal situation and the 6MWT for both groups, there was a significant difference (Wilcoxon, p<0.01) on that refers to the VO2/VO2max and VE/MVV. For oxygenation, verified this behavior only for G1 and in relation to SD, for both groups. Concluded that there was more metabolic and ventilatory for G1 and the 6MWT characterizes itself as an activity of high intensity even for individuals with COPD, like healthy individuals; suggesting the necessity that methodology of this test is well grounded and studied.