Walking and postural balance in adults with severe short stature due to isolated GH deficiency.

OBJECTIVES: Walking and postural balance are extremely important to obtain food and to work. Both are critical for quality of life and ability to survive. While walking reflects musculoskeletal and cardiopulmonary systems, postural balance depends on body size, muscle tone, visual, vestibular and nervous systems. Since GH and IGF-I act on all these systems, we decided to study those parameters in a cohort of individuals with severe short stature due to untreated isolated GH deficiency (IGHD) caused by a mutation in the GHRH receptor gene. These IGHD subjects, despite reduction in muscle mass, are very active and have normal longevity. METHODS: In a cross-sectional study, we assessed walking (by a 6-min walk test), postural balance (by force platform) and fall risk (by the 'Timed Up and Go' test) in 31 IGHD and 40 matched health controls. RESULTS: The percentage of the walked distance measured in relation to the predicted one was similar in groups, but higher in IGHD, when corrected by the leg length. Absolute postural balance data showed similar velocity of unipodal support in the two groups, and better values, with open and closed eyes and unipodal support, in IGHD, but these differences became non-significant when corrected for height and lower-limb length. The time in 'Timed Up and Go' test was higher in IGHD cohort, but still below the cut-off value for fall risk. CONCLUSION: IGHD subjects exhibit satisfactory walking and postural balance, without increase in fall risk.

Adult individuals with congenital, untreated, severe isolated growth hormone deficiency have satisfactory muscular function.

PURPOSE: While growth hormone (GH) and the insulin-like growth factor type I (IGF-I) are known to exert synergistic actions on muscle anabolism, the consequences of prolonged GH deficiency (GHD) on muscle function have not been well defined. We have previously described a large cohort of subjects with isolated GHD (IGHD) caused by a mutation in the GH-releasing hormone receptor gene, with low serum levels of GH and IGF-I. The aim of this study was to assess muscular function in these IGHD subjects. METHODS: A total of 31 GH-naïve IGHD (16 males) and 40 control (20 males) subjects, matched by age and degree of daily physical activity, were enrolled. Fat free mass was measured by bioelectrical impedance; muscle strength by dynamometry of handgrip, trunk extension, and knee extension; myoelectric activity and muscle fatigue by fractal dimension; conduction velocity in vastus medialis, rectus femoris, and vastus lateralis muscles by surface electromyography. RESULTS: The IGHD group showed higher knee extension strength both when corrected for weight and fat free mass, and higher handgrip and trunk extension strength corrected by fat free mass. They also exhibit higher conduction velocity of the muscles vastus medialis, rectus femoris, and vastus lateralis, but lower free fat mass and myoelectric activity of the vastus medialis, rectus femoris and vastus lateralis. There were no differences between the two groups in fractal dimension in all studied muscles. CONCLUSION: Individuals with untreated IGHD have better muscle strength parameters adjusted for weight and fat free mass than controls. They also exhibit greater peripheral resistance to fatigue, demonstrating satisfactory muscle function.

High-intensity interval training versus moderate-intensity continuous training on exercise capacity and quality of life in patients with coronary artery disease: A systematic review and meta-analysis.

Background Exercise is an effective strategy for reducing total and cardiovascular mortality in patients with coronary artery disease. However, it is not clear which modality is best. We performed a meta-analysis to investigate the effects of high-intensity interval versus moderate-intensity continuous training of coronary artery disease patients. Methods We searched MEDLINE, PEDro, LILACS, SciELO and the Cochrane Library (from the earliest date available to November 2016) for controlled trials that evaluated the effects of high-intensity interval versus moderate-intensity continuous training for coronary artery disease patients. Weighted mean differences and 95% confidence intervals were calculated, and heterogeneity was assessed using the I2 test. Results Twelve studies met the study criteria, including 609 patients. High-intensity interval training resulted in improvement in peak oxygen uptake weighted mean difference (1.3 ml/kg/min, 95% confidence interval: 0.6-1.9, n = 594) compared with moderate-intensity continuous training. No significant difference in physical, emotional, and social domain of quality of life was found for participants for participants in the high-intensity interval training group compared with the moderate-intensity continuous training group. Sub-analysis of three studies with isocaloric exercise training showed no significant difference in peak oxygen uptake weighted mean difference (0.4 ml/kg/min, 95% confidence interval: -0.1-0.9, n = 137) for participants in the high-intensity interval training group compared with moderate-intensity continuous training group. Conclusions High-intensity interval training may improve peak oxygen uptake and should be considered as a component of care of coronary artery disease patients. However, this superiority disappeared when isocaloric protocol is compared.

Pre- and postoperative inspiratory muscle training in patients undergoing cardiac surgery: systematic review and meta-analysis.

OBJECTIVE: To determine the effects of pre- and postoperative inspiratory muscle training on length of postoperative hospital stay and pulmonary function in patients undergoing cardiac surgery. DESIGN AND METHODS: We conducted a systematic search using databases (MEDLINE, CINAHL, EMBASE, PEDro and the Cochrane) to find controlled trials evaluating the effects of pre- and postoperative inspiratory muscle training. RESULTS: Eight studies fulfilled the inclusion criteria. Four were about preoperative inspiratory muscle training (416 patients), three about postoperative inspiratory muscle training (115 patients) and one study about pre- and postoperative inspiratory muscle training (43 patients). Preoperative inspiratory muscle training resulted in improvement in: Reduction in length of postoperative hospital stay of -2 days (95% CI -3.4, -0.7, N = 302), inspiratory pressure of 16.7 cm H2O (95% CI 13.8, 19.5, N = 386), forced expiratory volume in one second of 3% predicted (95% CI 0.1, 6, N = 140), forced vital capacity of 4.6% predicted (95% CI 1.9, 7.4, N = 140). Patients that received preoperative training had an inspiratory muscle training reduced risk of postoperative pulmonary complications, (RR = 0.6; 95% CI 0.5 to 0.8; P = 0.0004, N = 386). Postoperative inspiratory muscle training resulted in improvement in inspiratory pressure of 16.5 cm H2O (95% CI 4.9, 27.8, N = 115), and tidal volume of 185 ml (95% CI 19.7, 349.8, N = 85). CONCLUSION: Pre- and postoperative inspiratory muscle training showed to be a beneficial intervention in the treatment of patients undergoing cardiac surgery.

Effects of high-intensity aerobic interval training vs. moderate exercise on hemodynamic, metabolic and neuro-humoral abnormalities of young normotensive women at high familial risk for hypertension.

Exercise training has an important role in the prevention and treatment of hypertension, but its effects on the early metabolic and hemodynamic abnormalities observed in normotensive offspring of hypertensive parents (FH+) have not been studied. We compared high-intensity interval (aerobic interval training, AIT) and moderate-intensity continuous exercise training (CMT) with regard to hemodynamic, metabolic and hormonal variables in FH+ subjects. Forty-four healthy FH+ women (25.0+/-4.4 years) randomized to control (ConFH+) or to a three times per week equal-volume AIT (80-90% of VO(2MAX)) or CMT (50-60% of VO(2MAX)) regimen, and 15 healthy women with normotensive parents (ConFH-; 25.3+/-3.1 years) had their hemodynamic, metabolic and hormonal variables analyzed at baseline and after 16 weeks of follow-up. Ambulatorial blood pressure (ABP), glucose and cholesterol levels were similar among all groups, but the FH+ groups showed higher insulin, insulin sensitivity, carotid-femoral pulse wave velocity (PWV), norepinephrine and endothelin-1 (ET-1) levels and lower nitrite/nitrate (NOx) levels than ConFH- subjects. AIT and CMT were equally effective in improving ABP (P<0.05), insulin and insulin sensitivity (P<0.001); however, AIT was superior in improving cardiorespiratory fitness (15 vs. 8%; P<0.05), PWV (P<0.01), and BP, norepinephrine, ET-1 and NOx response to exercise (P<0.05). Exercise intensity was an important factor in improving cardiorespiratory fitness and reversing hemodynamic, metabolic and hormonal alterations involved in the pathophysiology of hypertension. These findings may have important implications for the exercise training programs used for the prevention of inherited hypertensive disorder.

A cutoff point for peak oxygen consumption in the prognosis of heart failure patients with ß-blocker therapy.

PURPOSE: Beta-blockers (BB) have shown to improve outcomes among heart failure patients (HF). Adequate risk stratification is still a major concern for HF. The prognostic indexes have been detected, but only few parameters maintain consistently high power in predicting progression of disease and mortality. Peak oxygen consumption (VO(2) peak, ml kg(-1) min(-1)) is traditionally used for risk stratification in HF, however, there is limited evidence regarding predictive value of VO(2) peak in patients taking BB. METHODS: Two hundred twenty nine patients, aged 49 ± 13 years with diagnosed HF for more than 6 months due to ischemic (n=73), idiopathic dilated (n=149) and Chagas disease (n=7) underwent a cardiopulmonary exercise test (CPX). The ejection fraction was 38 ± 10%; clinical stability was defined as no change in the NYHA class or absence of hospitalization for heart failure and stable medical treatment during 3 months prior to CPX. Subjects were tracked for cardiac-related mortality after CPX. RESULTS: The mean follow-up period was 2.5 ± 1.1 years and means value for VO(2) peak was 16.3 ± 4. Current BB therapy included carvedilol (83.4%), metoprolol (7.8%), bisoprolol (3.9%) and others (4.8%). The area under the ROC curve for VO(2) peak was 0.80 (95% CI: 0.69-0.90, optimal threshold: 12.5 and 82% sensitivity/26% specificity, p<0.001). Kaplan-Meier analysis that revealed event-free survival for subjects in < and >12.5 was 28% and 2.8%, respectively (long-rank 34.8; p<0.001). CONCLUSIONS: VO(2) peak seems to maintain prognostic value in HF patients BB therapy. The present study also provides new evidence that optimal threshold value for VO(2) peak in the BB era is 12.5 ml kg(-1) min(-1).

Effect of exercise training on 24-hour ambulatory blood pressure monitoring in heart failure patients.

The aim of this study was to evaluate the 24-hour ambulatory blood pressure monitoring (ABPM) response to exercise training (ET) in heart failure (HF) patients. Twelve HF patients and 15 sedentary healthy controls underwent ET for 2 months (3 times per week from 80%-90% of the ventilatory threshold). ABPM was performed before and 2 days after the last exercise season. Despite the fact that ET in HF patients was associated with significant improvements in peak oxygen consumption (pVO2), there were no significant changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR). On the other hand, controls decreased 24-hour mean SBP (117+/-8-115+/-9 mm Hg, P=.019) and 24-hour mean DBP (73+/-6-71+/-5 mm Hg, P=.016), mainly at nighttime SBP (107+/-8-103+/-9, P=.0004) and DBP (63+/-5-59+/-5 mm Hg, P<.0001). No changes in HR were found in controls. Values of 24-hour blood pressure did not change with ET in HF patients.

Inverse correlation between testosterone and ventricle ejection fraction, hemodynamics and exercise capacity in heart failure patients with erectile dysfunction.

BACKGROUND: Neurohormonal activation and abnormalities in growth hormone and testosterone concentrations have been reported in heart failure (HF). Erectile dysfunction(ED) is common in these patients and contributes to a low quality of life. No data are known regarding the correlation between testosterone and hemodynamics, exercise capacity and cardiac function in HF patients with ED, a marker of endothelial dysfunction. The aim of this study was to correlate testosterone levels with cardiac function, hemodynamic and exercise capacity in HF patients with ED. MATERIALS AND METHODS: Fifteen HF patients underwent a six-minute treadmill cardiopulmonary walking test (6'CWT) and, ten minutes later, a maximum cardiopulmonary exercise test. Also, testosterone and other hormones were determined at rest. RESULTS: Among hemodynamic variables only diastolic blood pressure on 6'CWT was correlated with testosterone levels(r=-0.66, p=0.007). The variables on exercise tests, VE/VCO2 slope and oxygen consumption did not show any correlation, except the distance at 6'CWT (r=0.50, p=0,047). Right and left ventricle ejection fraction showed inverse correlation with testosterone (r=-0.55, p=0.03 and r=-0.69, p=0.004 respectively). CONCLUSION: Testosterone levels correlated directly with distance at six-minute cardiopulmonary walk test and inversely with diastolic blood pressure, right and left ventricle ejection fraction in heart failure patients with erectile dysfunction. Further elucidation of mechanisms as regards testosterone action in these patients is warranted.

Inverse correlation between testosterone and ventricle ejection fraction, hemodynamics and exercise capacity in heart failure patients with erectile dysfunction

BACKGROUND: Neurohormonal activation and abnormalities in growth hormone and testosterone concentrations have been reported in heart failure (HF). Erectile dysfunction(ED) is common in these patients and contributes to a low quality of life. No data are known regarding the correlation between testosterone and hemodynamics, exercise capacity and cardiac function in HF patients with ED, a marker of endothelial dysfunction. The aim of this study was to correlate testosterone levels with cardiac function, hemodynamic and exercise capacity in HF patients with ED. MATERIALS AND METHODS: Fifteen HF patients underwent a six-minute treadmill cardiopulmonary walking test (6'CWT) and, ten minutes later, a maximum cardiopulmonary exercise test. Also, testosterone and other hormones were determined at rest. RESULTS: Among hemodynamic variables only diastolic blood pressure on 6'CWT was correlated with testosterone levels(r =- 0.66, p = 0.007). The variables on exercise tests, VE/VCO2 slope and oxygen consumption did not show any correlation, except the distance at 6'CWT (r = 0.50, p = 0,047). Right and left ventricle ejection fraction showed inverse correlation with testosterone (r =- 0.55, p = 0.03 and r =- 0.69, p = 0.004 respectively). CONCLUSION: Testosterone levels correlated directly with distance at six-minute cardiopulmonary walk test and inversely with diastolic blood pressure, right and left ventricle ejection fraction in heart failure patients with erectile dysfunction. Further elucidation of mechanisms as regards testosterone action in these patients is warranted.