RESUMO
The 2-Minute Step Test (2MST) has been presented as an alternative to the 6-Minute Walk Test (6MWT) based on the association between the two tests in older adults; however, some authors propose that it should not be a substitute but rather a complement to the latter in the fitness evaluation. Specifically, in coronary disease, despite the potential and clinical utility of 2MST, the relationship of both tests in this population is unknown. This study aimed to determine the relationship between 6MWT and 2MST and to explore the relationship of biodemographic factors for both tests in subjects with treated coronary artery disease. For this, the 6MWT and the 2MST were applied to patients with coronary artery disease treated in 6 hospitals in Chile between May 2019 and February 2020. Additionally, lower limb strength was assessed by a chair-stand test, grip strength was assessed by a dynamometer, and physical measurements were applied. In total, 163 participants underwent both tests (average age = 58.7 ± 9.8 years; 73.6% men; 64.4% revascularized by angioplasty; 28.2% revascularized by surgery, and 7.4% treated by drugs or thrombolysis). Heart rate was higher at the end of the 6MWT, while the perception of effort was greater at the end of the 2MST. There was a weak positive correlation between the 6MWT and the 2MST in subjects with treated coronary disease (r = 0.28, p = 0.0003). While age (r = -0.27), weight (r = 0.25), height (r = 0.49), and strength of both lower limbs (r = 0.41) and grip strength (r = 0.53) correlated weakly or moderately to the covered distance in 6MWT, the number of steps by the 2MST correlated only weakly to height (r = 0.23), lower limb strength (r = 0.34), and grip strength (r = 0.34). Age, weight, height, lower limb strength, and grip strength would explain better the meters walked in the 6MWT than the steps achieved in the 2MST. With these findings, we can conclude that, in patients with treated coronary artery disease, it does not seem advisable to replace 6MWT with 2MST when it is possible to do so. Additionally, the 2MST may provide additional information in the fitness evaluation. However, the usefulness of 2MST in this population needs to be further studied.
RESUMO
A doença renal crônica (DRC) é uma condição clínica de alto risco cardiovascular e os pacientes nos estágios mais avançados da doença que dependem de terapia renal substitutiva frequentemente tem prejuízo cardiorespiratório, níveis elevados de pressão arterial (uso de múltiplas medicações para controle), modulação autonômica prejudicada e graus variados de inflamação. Deste modo este estudo tem como objetivo verificar se o exercício físico aeróbio intradialítico tem impacto em modificar estas alterações. Os pacientes foram selecionados em duas unidades de hemodiálise em São Luís do Maranhão, Brasil, entre junho de 2016 e outubro de 2019, e foram alocados conforme aceitação em grupo controle (GC) e grupo exercício (GE). O GE foi submetido a treinamento aeróbio com bicicleta por um período de 12 semanas. Avaliação física antropométrica, teste de caminhada de 6 minutos (TC6m), ecocardiograma, eletrocardiograma com análise da variabilidade da frequência cardíaca e medidas laboratoriais foram realizadas incluindo interleucina 6 (IL6) antes e após 12 semanas em ambos os grupos. Trinta e um pacientes foram avaliados 15 pacientes no grupo controle (GC) e 16 pacientes no grupo exercício (GE). Após 12 semanas de treinamento houve diminuição da pressão arterial sistólica do grupo exercício em relação ao basal (129,8 ± 9,41mmHg vs 112,00 ± 12,0 mmHg p = 0,03). Não houve alterações na composição corporal e na maioria dos exames laboratoriais, exceto pelo aumento do KTV (índice de adequação de diálise) e diminuição do LDL colesterol no grupo exercício em relação ao grupo controle. No entanto, os níveis de HDL colesterol aumentaram (39,92 ± 6,1 mg/dL vs 48,00 ± 7,85 mg/dL p = 0,02) e IL6 diminuíram (4,56 ± 1,2 pg / mL vs 2,14 ± 1,0 pg / mL p = 0,02). Houve aumento da distância percorrida no teste de caminhada no grupo exercício (473,80 ± 98,6 metros vs 573,50 ± 74,22 metros p = 0,01). Na avaliação ecocardiográfica, verificou-se que no GE houve diminuição da pressão da artéria pulmonar estimada (31,38 ± 2,9 mmhg vs 24,2 ± 1,7 mmhg p = 0,001). Houve melhora na modulação autonômica no GE (RMSSD 11,7 ± 4,2 vs 18,4 ± 5,7 p=0,02), LFnu (52,9 ± 17,2 vs 32,0 ± 18,2 p=0,02) e HFnu (48,1 ± 17,2 vs 68,0 ± 18,2 p=0,01). Não foram evidenciados efeitos adversos e não houve abandono do treinamento. Baseados nestes resultados, é possível concluir que o exercício aeróbio intradialítico por 12 semanas pode melhorar parâmetros cardiorrespiratórios, hemodinâmicos e autonômicos, com boa aderência e sem eventos adversos, podendo ser usado como medida coadjuvante para melhora clínica destes pacientes.
Chronic kidney disease (CKD) is a clinical condition of high cardiovascular risk and patients in the more advanced stages of the disease who depend on renal replacement therapy often experience cardiorespiratory impairment, high blood pressure levels (use of multiple medications for control), modulation impaired autonomy and varying degrees of inflammation. Thus, this study aims to verify whether intradialytic aerobic exercise has an impact on modifying these variables. The patients were selected in two hemodialysis units in São Luís do Maranhão, Brazil, between May 2016 and October 2019, and were allocated according to acceptance in the control group (CG) and exercise group (EG). The group exercise was submitted to aerobic exercise with bicycle for a period of 12 weeks. Anthropometric physical evaluation, 6-minute walk test (6MWT), echocardiogram, electrocardiogram with analysis of heart rate variability (VFC) and laboratory measurements were performed including interleukin 6 (IL6) before and after 12 weeks in both groups. Thirty-one patients were evaluated 15 patients in the control group (CG) and 16 patients in the exercise group (EG). After 12 weeks of training, there was a decrease in systolic blood pressure in the exercise group compared to baseline (129.8 ± 9.41 mmHg vs 112.00 ± 12.0 mmhg p = 0.03). There were no changes in body composition and in most laboratory tests, except for an increase in KTV (dialysis adequacy index) and a decrease in LDL cholesterol in the exercise group compared to the control group. However, HDL cholesterol levels increased (39.92 ± 6.1 mg / dL vs 48.00 ± 7.85 mg / dL p = 0.02) and IL6 decreased (4.56 ± 1.2 pg / mL vs 2.14 ± 1.0 pg / mL p = 0.02). There was an increase in the distance covered in the walking test in the exercise group (473.80 ± 98.6 m vs 573.50 ± 74.22 m p = 0,01). In the echocardiographic evaluation, it was found that in the EG there was a decrease in the estimated pulmonary artery pressure (31.38 ± 2.9 mmhg vs 24.2 ± 1.7 mmhg p = 0.001). There was an improvement in autonomic modulation in the EG (RMSSD 11.7 ± 4.2 vs 18.4 ± 5.7 p = 0.02), LFnu (52.9 ± 17.2 vs 32.0 ± 18.2 p = 0.02) and HFnu (48.1 ± 17.2 vs 68.0 ± 18.2 p = 0.01). There were no adverse effects and training was not abandoned. Based on these results, it is possible to conclude that intradialytic aerobic exercise for 12 weeks can improve cardiorespiratory, hemodynamic, and autonomic parameters, with good adherence and without adverse events, and can be used as a supporting measure for the clinical improvement of these patients.
Assuntos
Exercício Físico , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/fisiopatologia , Artéria Pulmonar/fisiopatologia , Pressão Sanguínea , Ecocardiografia , Interleucina-6 , Terapia de Substituição Renal , Eletrocardiografia , Pressão Arterial , Teste de Caminhada/instrumentação , Fatores de Risco de Doenças Cardíacas , HDL-Colesterol/química , LDL-Colesterol/químicaRESUMO
Background: The six minute walking distance test (6MWD) is widely used to evaluate exercise capacity in several diseases due to its simplicity and low cost. Aim: To establish reference values for 6MWD in healthy Chilean individuals. Material and methods: We studied 175 healthy volunteers aged 20-80 years (98 women) with normal spirometry and without history of respiratory, cardiovascular or other diseases that could impair walking capacity. The test was performed twice with an interval of 30 min. Heart rate, arterial oxygen saturation (with a pulse oxymeter) and dyspnea were measured before and after the test. Results: Walking distance was 576 ± 87 m in women and 644 ± 84 m in men (p < 0.0001). For each sex, a model including age, height and weight produced 6MWD prediction equations with a coefficient of determination (R²) of 0.63 for women and 0.55 for men. Conclusions: Our results provide reference equations for 6MWD that are valid for healthy subjects between 20 and 80 years old.