OBJECTIVES: To identify the clinical discriminative value and determinants of arterial stiffness in individuals with type 2 diabetes mellitus (T2DM). METHODS: This prospective cohort study included 51 individuals (53.57±9.35 years) diagnosed with T2DM (stage glucose≥126 mg/dL; diagnostic time: 87.4±69.8 months). All participants underwent an initial evaluation of personal habits, medications, and history; arterial stiffness assessment by carotid-femoral pulse wave velocity (cfPWV) using SphygmoCor; and blood laboratory analysis. A statistical analysis was performed using SPSS software, and values of p≤0.05 were considered significant. RESULTS: A cut-off cfPWV value of 7.9 m/s was identified for T2DM [Sensitivity (SE): 90% and Specificity (SP): 80%]. A subgroup analysis revealed higher glycated hemoglobin (Hb1Ac) (p=0.006), obesity (p=0.036), and dyslipidemia (p=0.013) than those with cfPWV ≥7.9 m/s. Multivariate analysis identified higher stage glucose (p=0.04), Hb1Ac (p=0.04), hypertension (p=0.001), and dyslipidemia (p=0.01) as determinant factors of cfPWV; positive and significant correlation between cfPWV and glucose (r=0.62; p=0.0003) and Hb1Ac (r=0.55; p=0.0031). CONCLUSIONS: In T2DM, an indicator of the discriminative value of arterial stiffness was cfPWV of 7.9 m/s. Clinical findings and comorbidities, such as hypertension, glucose, poor glycemic control, and dyslipidemia, were associated with and were determinants of arterial stiffness in T2DM. Reinforcement of monitoring risk factors, such as hypertension, dyslipidemia, and glycemic control, seems to be essential to the process of arterial stiffening. Confirmation of this discriminative value in larger populations is recommended.

A variabilidade da frequência cardíaca (VFC) e a eletromiografia de superfície (EMGs) são ferramentas importantes na avaliação do sistema autonômico cardíaco e dos parâmetros neuromusculares respetivamente. O objetivo do estudo foi avaliar o comportamento da VFC e da EMGs do músculo vasto lateral em dois protocolos de exercício no ciclo ergómetro em 60 e 80 rpm. Oito homens ciclistas treinados há pelo menos 2 anos foram avaliados. Foi verificada redução dos índices RMSSD e SDNN da VFC seguida por estabilização (p<0.05) e aumento da amplitude do sinal da EMGs (p<0.05) em ambos os protocolos. Correlações significativas foram observadas entre as respostas da VFC e da EMGs na cadência de 60 rpm (RMSSD e EMGs: r = -0.42, p =0.03; SDNN e EMGs: r = -0.45, p =0.01) e 80 rpm (RMSSD e EMGs: r = -0.47, p=0.02; SDNN e EMGs: r = -0.49, p=0.01), e não houve diferença destas variáveis entre os dois protocolos. Concluímos que as respostas parassimpática cardíaca e da EMGs são independentes das cadências aplicadas na mesma intensidade do esforço.

The heart rate variability (HRV) and surface electromyography (sEMG) are important tools in the evaluation of cardiac autonomic system and neuromuscular parameters, respectively. The aim of the study was to evaluate the behavior of HRV and sEMG of the vastus lateralis in two exercise protocols on a cycle ergometer at 60 and 80 rpm. Eight healthy men cyclists who have trained for at least two years were evaluated. Reduction was observed followed by stabilization of RMSSD and SDNN indices of HRV (p<0.05) along with increases in the amplitude of the sEMG signal (p<0.05) in both protocols. Significant correlations were observed between the responses of HRV and sEMG in the cadence of 60 rpm (RMSSD and sEMG: r = -0.42, p=0.03; SDNN and sEMG: r = -0.45, p=0.01) and 80 rpm (RMSSD and sEMG: r = -0.47, p=0.02; SDNN and sEMG: r = -0.49, p=0.01), yet no difference was observed for these variables between the two protocols. We concluded that the parasympathetic cardiac responses and sEMG are independent of cadences applied at the same power output.

Abstract Objective: To evaluate heart rate variability during an inspiratory muscle endurance protocol at three different load levels [30%, 60% and 80% of maximal inspiratory pressure], in patients who had previously undergone coronary artery bypass grafting. Methods: Nineteen late postoperative myocardial revascularization patients participating in a cardiovascular rehabilitation program were studied. Maximal inspiratory pressure maneuvers were performed. An inspiratory muscle endurance protocol at 30%, 60% and 80% of maximal inspiratory pressure was applied for four minutes each, in random order. Heart rate and RR intervals were recorded and heart rate variability was analyzed by time (RMSSD-the mean of the standard deviations for all R-R intervals, and RMSM-root-mean square differences of successive R-R intervals) and frequency domains indices (high and low frequency) in normalized units. ANOVA for repeated measurements was used to compare heart rate variability indices and Student t-test was used to compare the maximal inspiratory pressure and maximal expiratory pressure values. Results: Heart rate increased during performance of maximal respiratory pressures maneuvers, and the maximal inspiratory pressure and maximal expiratory pressure mean values were significantly lower than predicted values (P <0.05). RMSSD increased significantly at 80% in relation to rest and 30% of maximal inspiratory pressure and RMSM decreased at 30% and 60% of maximal inspiratory pressure in relation to rest (P <0.05). Additionally, there was significant and progressive decrease in low frequency and increase in high frequency at 30%, 60% and 80% of maximal inspiratory pressure in relation to the resting condition. Conclusion: These results suggest that respiratory muscle training at high intensities can promote greater parasympathetic activity and it may confer important benefits during a rehabilitation program in post-coronary artery bypass grafting.

Fundamento:Os índices da Potência Circulatória (PC) e Potência Ventilatória (PV) têm sido utilizados para avaliação clínica de pacientes com insuficiência cardíaca, mas nenhum estudo avaliou esses índices em pacientes com Doença Arterial Coronariana (DAC).Objetivo:Caracterizar ambos os índices em pacientes com DAC comparados a indivíduos saudáveis.Métodos:Oitenta e sete homens [grupo DAC = 42 sujeitos e, grupo controle (GC) = 45 sujeitos] com idade entre 45 e 65 anos foram incluídos. Um Teste de Exercício Cardiopulmonar (TECP) foi realizado em esteira e as seguintes variáveis foram obtidas: 1) consumo de oxigênio (VO2) pico; 2) Frequência Cardíaca (FC) pico; 3) Pressão Arterial (PA) pico; 4) duplo produto pico (PA sistólica pico x FC pico); 5) pulso de oxigênio pico (VO2 pico dividido pela FC pico); 6) eficiência ventilatória para o consumo de oxigênio (OUES); 7) eficiência ventilatória para a produção de dióxido de carbono (VE/VCO2 slope); 8) PC (VO2 pico x PA sistólica pico); e 9) PV (PA sistólica pico dividido pelo VE/VCO2slope).Resultados:O grupo DAC apresentou valores significativamente menores das seguintes variáveis no pico do exercício: VO2 (p < 0,001), FC (p < 0,001), PA sistólica (p < 0,001), duplo produto (p < 0,001), pulso de oxigênio (p = 0,008), OUES (p < 0,001), PC (p < 0,001) e PV (p < 0,001), e valores significativamente maiores de PA diastólica (p = 0,004) e VE/VCO2 slope (p < 0,001) em relação ao GC. Uma análise de regressão pelo método stepwise mostrou que a PC foi influenciada pelo grupo (R2 = 0,44, p < 0,001) e a PV tanto pelo grupo quanto pelo número de vasos com estenose pós tratamento (efeito de interação: R2 = 0,46, p < 0,001).Conclusion:Os índices da PC e PV foram menores em homens com DAC comparados ao GC, podendo dessa forma ser utilizados na caracterização dessa população.

Background:Circulatory power (CP) and ventilatory power (VP) are indices that have been used for the clinical evaluation of patients with heart failure; however, no study has evaluated these indices in patients with coronary artery disease (CAD) without heart failure.Objective:To characterize both indices in patients with CAD compared with healthy controls.Methods:Eighty-seven men [CAD group = 42 subjects and healthy control group (CG) = 45 subjects] aged 40–65 years were included. Cardiopulmonary exercise testing was performed on a treadmill and the following parameters were measured: 1) peak oxygen consumption (VO2), 2) peak heart rate (HR), 3) peak blood pressure (BP), 4) peak rate-pressure product (peak systolic HR x peak BP), 5) peak oxygen pulse (peak VO2/peak HR), 6) oxygen uptake efficiency (OUES), 7) carbon dioxide production efficiency (minute ventilation/carbon dioxide production slope), 8) CP (peak VO2 x peak systolic BP) and 9) VP (peak systolic BP/carbon dioxide production efficiency).Results:The CAD group had significantly lower values for peak VO2 (p < 0.001), peak HR (p < 0.001), peak systolic BP (p < 0.001), peak rate-pressure product (p < 0.001), peak oxygen pulse (p = 0.008), OUES (p < 0.001), CP (p < 0.001), and VP (p < 0.001) and significantly higher values for peak diastolic BP (p = 0.004) and carbon dioxide production efficiency (p < 0.001) compared with CG. Stepwise regression analysis showed that CP was influenced by group (R2 = 0.44, p < 0.001) and VP was influenced by both group and number of vessels with stenosis after treatment (interaction effects: R2 = 0.46, p < 0.001).Conclusion:The indices CP and VP were lower in men with CAD than healthy controls.

BACKGROUND: A synchronism exists between the respiratory and cardiac cycles. However, the influence of the inspiratory muscle weakness in chronic obstructive pulmonary disease (COPD) on cardiac autonomic control is unknown. The purpose of the present investigation was to evaluate the influence of respiratory muscle strength on autonomic control in these patients. METHODS: Ten chronic obstructive pulmonary disease patients (69±9 years; FEV1/FVC 59±12% and FEV1 41±11% predicted) and nine age-matched healthy volunteers (64±5 years) participated in this study. Heart-rate variability (HRV) was obtained at rest and during respiratory sinusal arrhythmia maneuver (RSA-M) by electrocardiograph. RESULTS: Chronic obstructive pulmonary disease patients demonstrated impaired cardiac autonomic modulation at rest and during RSA-M when compared with healthy subjects (p<0.05). Moreover, significant and positive correlations between maximal inspiratory pressure (MIP) and the inspiratory-expiratory difference (ΔIE) (r = 0.60, p<0.01) were found. CONCLUSION: Patients with chronic obstructive pulmonary disease presented impaired sympathetic-vagal balance at rest. In addition, cardiac autonomic control of heart rate was associated with inspiratory muscle weakness in chronic obstructive pulmonary disease. Based on this evidence, future research applications of respiratory muscle training may bring to light a potentially valuable target for rehabilitation.

CONTEXTO E OBJETIVOS: A força muscular respiratória é relevante para a situação clínica de pacientes idosos, particularmente os que apresentam doença cardíaca ou respiratória. Os objetivos deste estudo foram avaliar a força muscular respiratória de mulheres idosas asiladas, comparar com os valores preditos para a população brasileira e correlacioná-los com a idade e características antropométricas. TIPO DE ESTUDO E LOCAL: Estudo transversal desenvolvido pelo Departamento de Fisioterapia da Universidade Camilo Castelo Branco. MÉTODOS: Foram estudadas 56 mulheres idosas asiladas (74,87 ± 10,55 anos) sendo avaliadas em oito instituições em três cidades do interior do estado de São Paulo, entre janeiro de 2005 e março de 2006. Elas foram separadas em três subgrupos: de 60-69 anos (n = 20), de 70-79 anos (n = 18) e de 80-89 anos (n = 18). As pressões respiratórias máximas foram obtidas através de um manovacuômetro. Os valores obtidos foram comparados entre os subgrupos e também com os preditos para a população brasileira. Análise de correlação foi aplicada para a idade, peso, altura e índice de massa corpórea com os valores das pressões respiratórias máximas. O nível de significância adotado foi P < 0,05. RESULTADOS: Não houve diferenças significativas das pressões respiratórias máximas entre os três subgrupos. Em relação aos valores preditos, as pressões respiratórias máximas obtidas foram significativamente menores nos três subgrupos. Correlações negativas entre as pressões respiratórias máximas e a idade e positivas em relação ao peso, altura e índice de massa corpórea foram encontradas. CONCLUSÕES: A força muscular respiratória é marcantemente reduzida em idosas asiladas de 60 a 89 anos, havendo correlação das pressões respiratórias máximas com a idade e com as características antropométricas.

CONTEXT AND OBJECTIVES: Respiratory muscle strength is relevant to the clinical situation of elderly patients, particularly those presenting with respiratory or cardiac diseases. The objectives of this study were to evaluate the respiratory muscle strength of institutionalized elderly women, compare this with predicted values for the Brazilian population and calculate the correlation with age and anthropometric characteristics. DESIGN AND SETTING: Cross-sectional study at the Department of Physiotherapy of Universidade Camilo Castelo Branco. METHODS: The participants were 56 institutionalized elderly women (74.87 ± 10.55 years of age), evaluated in eight institutions in three cities in the central region of the State of São Paulo, between January 2005 and March 2006. They were separated into three subgroups according to age: 60-69 years (n = 20), 70-79 (n = 18) and 80-89 years (n = 18). Maximal respiratory pressures were obtained using a manovacuometer. The values obtained were compared between subgroups and with predicted values. Correlation analysis was used to evaluate age, weight, height and body mass index in relation to maximal respiratory pressures. The significance level was P < 0.05. RESULTS: No significant differences in maximal respiratory pressures were seen between the three subgroups. The maximal respiratory pressures were significantly lower in the three subgroups, compared with predicted values. Negative correlations between maximal respiratory pressures and age and positive correlations in relation to weight, height and body mass index were found. CONCLUSIONS: Respiratory muscle strength was markedly reduced in institutionalized 60 to 89-year-old women and the values demonstrated correlations with age and anthropometric characteristics.