Exercise might improve cardiovascular autonomic regulation in adolescents with type 1 diabetes

Effects of Endurance Exercise Intensities on Autonomic and Metabolic Controls in Children with Obesity: A Feasibility Study Employing Online Exercise Training

Exercise is one of the major determinants of a healthy lifestyle, which is particularly important in childhood and serves as a powerful preventive tool. On the other hand, obesity and arterial hypertension rates are increasing in children, representing a huge risk for developing major cardiovascular and metabolic diseases in adult life. Of fundamental importance is the modality and volume of exercise required to obtain benefits. In this feasibility study, we considered a group of obese children, studied before and after a 12-week online exercise training program, and subdivided the participants into two groups considering the volume of exercise performed (above or below 1200 MET·min/week). This threshold level was applied in two different ways: subdivision A considered the total weekly physical activity volume (considering both time spent walking for at least 10 min consecutively and time spent performing structured exercise) and subdivision B considered only the weekly volume of structured exercise. We assessed autonomic and metabolic control and auxological and lifestyle parameters. We observed that the improved volume of structured exercise was associated with reduced arterial pressure percentile only in subdivision B and an improvement in markers of vagal and metabolic control was evident. Moreover, the 12-week online exercise training program, defined considering individual fitness level and progressively adapted as the goal was reached, proved to be sustainable from an economical and organizational point of view.

Progressive Additive Benefits of Prehabilitation and Subsequent Bariatric Surgery on Cardiac Autonomic Regulation as Assessed by Means of a Simple Unitary Composite Index: Preliminary Data from an Observational Study

Obesity is associated with an increased risk of several chronic comorbidities, which may also be determined by dysfunctional autonomic nervous system (ANS). The influence of bariatric surgery (BS) on ANS balance was explored in previous studies, but with high heterogeneity in both the assessment timing and methods employed. In the present observational study, we applied a clinical protocol which considers two subsequent phases. Twenty-nine non-diabetic obese subjects were studied at baseline (T0), after one month of lifestyle modification (prehabilitation) (phase 1-T1), and after eight months following BS (phase 2-T2). ANS regulation was assessed across the three study epochs by means of ANSI, a single composite percent-ranked proxy of autonomic balance, being free of gender and age bias, economical and simple to apply in a clinical setting. The aim of the present study was to investigate the effects of the clinical protocol based on prehabilitation and subsequent BS on the ANS regulation by means of ANSI. Potential intertwined correlations with metabolic parameters were also investigated. Notably, we observed a progressive improvement in ANS control, even by employing ANSI. Moreover, the reduction in the markers of sympathetic overactivity was found to significantly correlate with the amelioration in some metabolic parameters (fasting glucose, insulin levels, and waist circumference), as well as in stress and tiredness perception. In conclusion, this study provides convincing evidence that a unitary proxy of cardiac autonomic regulation (CAR) may reflect the progressive improvement in autonomic regulation following behavioral and surgical interventions in obese patients. Intriguingly, this might contribute to reducing cardiovascular and metabolic risk.

Correlation between impaired hemodynamic response and cardiopulmonary fitness in middle-aged type 2 diabetes mellitus patients: a case-control study

PURPOSE

Impaired cardiorespiratory fitness (CRF) is a predictor of mortality in patients with type 2 diabetes mellitus (T2DM). It is still not known how the exercise hemodynamic response correlates with CRF. The purpose was to assess the correlation between hemodynamic changes and CRF in middle-aged patients with T2DM.

METHODS

After 1:1 matching by age and sex, 139 T2DM patients and 139 non-T2DM controls who completed the exercise treadmill test were included. Maximal aerobic capacity (VO_2max), exercise-induced changes in heart rate (ΔHR), systolic blood pressure (ΔSBP), diastolic blood pressure (ΔDBP), and rate-pressure product (ΔRPP) were measured. HRR₁ was calculated as the maximum heart rate minus the heart rate after 1 min of rest.

RESULTS

Compared to the control population, T2DM patients had decreased ΔHR (87 (77, 97) v 93 (84, 104) bpm, p < 0.05), ΔRPP (3833.64 ± 1670.34 v 4381.16 ± 1587.78 bpm∙mmHg, p < 0.05), HRR₁ (21 (14, 27) v 21 (17, 27) bpm, p < 0.05), and VO_2max (32.76 ± 5.63 v 34.68 ± 5.70 ml/kg/min, p < 0.05). Multiple linear regression analysis showed that ΔHR and HRR₁, yielded a positive correlation with VO_2max in T2DM patients (β = 0.325, P < 0.001; β = 0.173, P = 0.01).

CONCLUSION

The presence of impaired hemodynamic response and VO_2max in middle-aged T2DM patients and the association of impaired ΔHR, HRR₁, and VO_2max may indicate a physiological pathway of impaired CRF, and our results support the need for cardiorespiratory screening and individualized treatment of middle-aged T2DM patients.

Evidence of Better Autonomic, Metabolic and Psychological Profile in Breast Cancer Survivors Meeting Current Physical Activity Recommendations: An Observational Study

The increased cardiometabolic risk observed in breast cancer survivors (BCS) is due to multiple mechanisms: Hormonal and immunological dysfunction are well-identified ones, while cardiac autonomic regulation (CAR) is less recognized but may play a new complementary role particularly relevant when considering conditions and behaviors associated with a better prognosis in BCS, such as physical training. This observational study investigated a group of consecutive (172) BCS subdivided in two groups: those who reached the physical activity goals above 600 (MET·min/week) and those who did not. We assessed CAR by autoregressive spectral analysis of cardiovascular variabilities (considering in particular the unitary autonomic nervous system index—ANSI), body mass composition, stress perception and lifestyle in order to verify possible differences due to execution of physical activity. Subjects who spontaneously met physical activity recommendations presented a better autonomic, metabolic and psychological profile compared to those who did not. Lower physical activity volume, poor metabolic parameters, increased stress and fatigue perception may cluster together, leading to worsened CAR. This control mechanism may play a complementary role in determining the increased cardiometabolic risk observed in BCS. Furthermore, it may also explain, albeit in part, the better prognosis observed in patients following interventions aiming to improve the sympathetic–parasympathetic balance, such as physical training, using a personalized medicine approach.

Interaction between Autonomic Regulation, Adiposity Indexes and Metabolic Profile in Children and Adolescents with Overweight and Obesity

Early obesity predicts initial modifications in cardiac and vascular autonomic regulation. The aim of this study was to assess the possible interaction between non-invasive measures of autonomic cardiovascular control and peripheral endothelium regulation in children with overweight and obesity. We involved 114 young subjects (77M/37F, 12.7 ± 2.2 years) with normal weight (NW, n = 46) to overweight or obesity (OB, n = 68). Multivariate statistical techniques utilizing a collection of modern indices of autonomic regulation, adiposity indexes and metabolic profile were employed. Resting values show substantial equivalence of data. Conversely, blood pressure variance is greater in NW/OB groups. The correlation matrix between major autonomic and metabolic/hemodynamic variables shows a clustered significant correlation between homogeneous indices. A significant correlation between metabolic indices and endothelial and autonomic control, mostly in its vascular end, was recorded. Particularly, the alpha index is significantly correlated with triglycerides (r = −0.261) and endothelial indices (RHI, r = 0.276). Children with obesity show a link between indices of autonomic and endothelial function, fat distribution and metabolic profile. The optimization of autonomic control, for instance by exercise/nutrition interventions, could potentially prevent/delay the occurrence of structural vascular damage leading to reduced cardiovascular health.

A pilot study of the effects of a high-intensity aerobic exercise session on heart rate variability and arterial compliance in adolescents with or without type 1 diabetes

Arterial compliance and autonomic regulation are predictors of cardiovascular disease. In adults, both are altered chronically by type 1 diabetes (T1D) and acutely by exercise; however, the effects of T1D and exercise are less clear in adolescents. We measured short-term effects of a high-intensity aerobic interval exercise session on cardiovascular and metabolic variables in normal weight adolescents with T1D or without T1D (Control). Energy expenditure (EE), heart rate variability (HRV), arterial compliance, and blood pressure (BP) were measured before exercise (baseline) and three times over 105 minutes postexercise. The T1D and control groups had similar cardiorespiratory fitness and accelerometer-measured physical activity. The T1D group had higher EE and fat oxidation throughout the trial, but postexercise changes were similar between groups. HRV transiently declined following exercise in both groups, but the T1D group had lower HRV at baseline. Among the measures of arterial compliance, the augmentation index declined postexercise while carotid-femoral pulse wave velocity and large artery elastic index remained unchanged. Central and brachial BP were unchanged following exercise until the final measurement, when a small increase occurred. However, arterial compliance and BP did not differ between groups. These results demonstrate that normal weight adolescents with T1D have impaired autonomic function and increased EE and fat oxidation compared to peers without diabetes who have similar levels of fitness and physical activity. However, acute cardiometabolic responses to exercise are normal in T1D with adequate glycemic control. Changes in arterial compliance and BP may take longer to emerge in relatively healthy adolescents with T1D.

Similar cardiovascular and autonomic responses in trained type 1 diabetes mellitus and healthy participants in response to half marathon

AIMS

This field experiment examined whether trained people with type 1 diabetes mellitus (T1D) have similar cardiovascular and baroreflex alterations after a 21-km running race when compared to healthy people.

METHODS

Nine T1D (39.0 ± 11.1 yr; 175.0 ± 10.2 cm; 70.8 ± 8.7 kg) were matched with 9 healthy participants (42.4 ± 5.8 yr; 175.7 ± 6.7 cm; 72.1 ± 8.5 kg) who ran an official half-marathon. Before and 1-hour after the race, cardiovascular variables, sympathetic activity (catecholamines), parasympathetic (heart rate variability analysis) modulation and cardiac baroreflex function (transfer function analysis) were assessed during supine rest and a squat stand test (forced blood pressure change).

RESULTS

Performance time and weight loss [104.0 ± 13.2 and 111.0 ± 18.7 min; -2.57 ± 1.05 kg (-1.88 ± 0.88%) and -2.29 ± 1.15 kg (-1.59 ± 0.59%)] for healthy and T1D participants, respectively) were similar. Before running, no significant differences in any cardiovascular or autonomic variables were noted between the groups. After 1 h of recovery, both groups exhibited post-exercise hypotension, accompanied by increased sympathetic activity, decreased parasympathetic modulation, and reduced cardiac baroreflex sensitivity.

CONCLUSIONS

Our results showed that the pattern of change in cardiovascular and autonomic nervous activity to strenuous exercise are well maintained in T1D participants with a training history of at least 5 years.

Can the use of a single integrated unitary autonomic index provide early clues for eventual eligibility for olympic games?

PURPOSE

Optimal autonomic regulation and stress resilience might be considered critical elements of athletic performance. We hypothesize that a novel unitary autonomic index for sports (ANSIs), together with a somatic stress related symptom score (4SQ) might help characterize athletes who were eventually selected for the Rio 2016 Olympic Games Italian team (Rio +).

METHODS

In this retrospective study we examined 778 athletes (age 24.4 ± 6.7 yrs) who underwent a planned yearly pre-participation screening. All athletes underwent clinical, autonomic and exercise ECG evaluation. The combination of vagal and sympathetic indices from RR variability into ANSIs was performed by radar plot and percent ranking of index variables. We assessed (Rio +) versus (Rio -) athletes also after subdivision into three sport intensity groups (low, mid and high intensity).

RESULTS

Overall there were no significant differences between (Rio +) and (Rio -) athletes when considering individual spectral derived variables. Conversely, the unitary Index ANSIs was significantly higher in (Rio +) compared to (Rio -) athletes (respectively 54.5 ± 29.5 and 47.9 ± 28.4 p = 0.014). This difference was particularly evident (p = 0.017) in the group of athletes characterized by both high static and dynamic components. 4SQ was smaller in the (Rio +) group, particularly in the groups of athletes characterized by both low-medium static and dynamic components.

CONCLUSIONS

ANSIs, a proxy of integrated cardiac autonomic regulation and simple assessment of resilience to stress, may differentiate Italian athletes who were eventually selected for participation in the 2016 Rio Olympic Games from those who were not, suggesting the possibility of a "winning functional phenotype".

Physical activity and autoimmune diseases: Get moving and manage the disease

Physical activity, by definition, is any skeletal muscle body movement that results in energy expenditure. In the last few decades, a plethora of scientific evidences have accumulated and confirmed the beneficial role of physical activity as a modifiable risk factor for a wide variety of chronic diseases including cardiovascular diseases (CVDs), diabetes mellitus and cancer, among others. Autoimmune diseases are a heterogeneous group of chronic diseases, which occur secondary to loss of self-antigen tolerance. With the advent of biological therapies, better outcomes have recently been noted in the management of autoimmune diseases. Nonetheless, recent research highlights the salient role of modifiable behaviors such as physical inactivity on various aspects of the immune system and autoimmune diseases. Physical activity leads to a significant elevation in T-regulatory cells, decreased immunoglobulin secretion and produces a shift in the Th1/Th2 balance to a decreased Th1 cell production. Moreover, physical activity has been proven to promote the release of IL-6 from muscles. IL-6 released from muscles functions as a myokine and has been shown to induce an anti-inflammatory response through IL-10 secretion and IL-1β inhibition. Physical activity has been shown to be safe in most of autoimmune diseases including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), inflammatory bowel diseases (IBD), as well as others. Additionally, the incidence of RA, MS, IBD and psoriasis has been found to be higher in patients less engaged in physical activity. As a general trend, patients with autoimmune diseases tend to be less physically active as compared to the general population. Physically active RA patients were found to have a milder disease course, better cardiovascular disease (CVD) profile, and improved joint mobility. Physical activity decreases fatigue, enhances mood, cognitive abilities and mobility in patients with MS. In SLE patients, enhanced quality of life and better CVD profile were documented in more physically active patients. Physically active patients with type 1 diabetes mellitus have a decreased risk of autonomic neuropathy and CVD. Both fibromyalgia and systemic sclerosis patients report decreased disease severity, pain, as well as better quality of life with more physical activity. Further, SSc patients improve their grip strength, finger stretching and mouth opening with increased level of exercise. The purpose of this paper is to review the clinical evidence regarding the safety, barriers to engagement, and impact of physical activity on autoimmune diseases.

Association of cardiac autonomic modulation with physical and clinical features of young people with type 1 diabetes

OBJECTIVE

The objective of this study was to verify possible associations between heart rate variability indices and physical activity, body composition, and metabolic and cardiovascular parameters in individuals with type 1 diabetes.

METHOD

A total of 39 young patients with type 1 diabetes were included. Body composition, physical activity, cardiovascular parameters, and metabolic parameters were assessed. For the heart rate variability analysis, heart rate was recorded beat-by-beat using a Polar S810i heart rate monitor for 30 minutes, with the volunteers in the supine position; subsequently, the following indices were considered: standard deviation of all normal RR intervals; root-mean square of differences between adjacent normal RR intervals in a time interval; percentage of adjacent RR intervals with a difference of duration >50 ms; high frequency component in milliseconds squared; high frequency component in normalised units; standard deviation of the instantaneous variability beat-to-beat; and standard deviation of the long-term variability. The association between the heart rate variability indices and independent variables was verified through linear regression in unadjusted and adjusted models (considering gender and age). The statistical significance was set at 5% and the confidence interval at 95%.

RESULTS

High values of at-rest heart rate were associated with reduced parasympathetic activity and global heart rate variability, and higher values of waist-to-hip ratio were related to lower parasympathetic activity, independent of age or gender.

CONCLUSION

For young patients with type 1 diabetes, increases in at-rest heart rate values are associated with reduced parasympathetic activity and global heart rate variability, whereas higher waist-to-hip ratio values are related to lower parasympathetic activity, both independent of age and gender.

Poor glycaemic control is associated with reduced exercise performance and oxygen economy during cardio-pulmonary exercise testing in people with type 1 diabetes

BACKGROUND

To explore the impact of glycaemic control (HbA_1c) on functional capacity during cardio-pulmonary exercise testing in people with type 1 diabetes.

METHODS

Sixty-four individuals with type 1 diabetes (age: 34 ± 8 years; 13 females, HbA_1c: 7.8 ± 1% (62 ± 13 mmol/mol), duration of diabetes: 17 ± 9 years) performed a cardio-pulmonary cycle ergometer exercise test until volitional exhaustion. Stepwise linear regression was used to explore relationships between HbA_1c and cardio-respiratory data with p ≤ 0.05. Furthermore, participants were divided into quartiles based on HbA_1c levels and cardio-respiratory data were analysed by one-way ANOVA. Multiple regression analysis was performed to explore the relationships between changes in time to exhaustion and cardio-respiratory data. Data were adjusted for confounder.

RESULTS

HbA_1c was related to time to exhaustion and oxygen consumption at the power output elicited at the sub-maximal threshold of the heart rate turn point (r = 0.47, R² = 0.22, p = 0.03). Significant differences were found at time to exhaustion between QI vs. QIV and at oxygen consumption at the power output elicited at the heart rate turn point between QI vs. QII and QI vs. QIV (p < 0.05). Changes in oxygen uptake, power output and in oxygen consumption at the power output elicited at the heart rate turn point and at maximum power output explained 55% of the variance in time to exhaustion (r = 0.74, R² = 0.55, p < 0.01).

CONCLUSIONS

Poor glycaemic control is related to less economical use of oxygen at sub-maximal work rates and an earlier time to exhaustion during cardio-pulmonary exercise testing. However, exercise training could have the same potential to counteract the influence of poor glycaemic control on functional capacity. Trial registration NCT01704417. Date of registration: October 11, 2012.

Swimming training attenuates the morphological reorganization of the myocardium and local inflammation in the left ventricle of growing rats with untreated experimental diabetes

Diabetic cardiomyopathy is associated with cardiac remodeling, myocardial dysfunction, low-grade inflammation, and reduced cardiac adiponectin in patients with type 1 diabetes mellitus (T1DM). Alternatively, physical exercise is an important strategy for the management of diabetes. This study aimed to investigate the influence of low-intensity swimming training in cardiac cytokines, structural remodeling, and cardiomyocyte contractile dysfunction in growing rats with untreated experimental DM. Thirty-day-old male Wistar rats were divided into four groups (n=14, per group): sedentary control (SC), exercised control (EC), sedentary diabetic (SD), and exercised diabetic (ED). Diabetes was induced by streptozotocin (60 mg kg(-1), i.p.). Animals from exercised groups swam (5 days/week, 90 min/day, loading up to 5% body weight around the animal's chest) for 8 weeks. The left ventricle (LV) was removed for molecular, morphological, and cardiomyocyte mechanical analysis. Diabetic animals presented cardiac remodeling with myocardial histoarchitectural disorganization, fibrosis, and necrosis. The capillary density was lower in diabetic animals. LV cardiomyocytes from diabetic animals exhibited more prolonged time to the peak of contraction and time to half relaxation than those from control animals. The cardiac levels of interleukin 10, nitric oxide, and total and high molecular weight (HMW) adiponectin were significantly decreased in diabetic animals. Exercise training reduced the level of TNF-α, increased capillary density, and attenuated the histopathological parameters assessed in diabetic rats. In conclusion, the cardiac structural remodeling coexists with reduced levels of total and HMW adiponectin, inflammation, and cardiomyocyte contractility dysfunction in experimental DM. More important, low-intensity swimming training attenuates part of these pathological changes, indicating the beneficial role for exercise in untreated T1DM.

Long-term effects of baroreflex activation therapy on glucose metabolism

AIMS

Sympathetic overactivity is one critical factor associated with the development of arterial hypertension, impaired insulin secretion and resistance. Some antihypertensives exert beneficial effects on glucose metabolism, whereas others lead to an impairment of metabolic state with consecutive weight gain. In resistant hypertension, baroreflex activation therapy (BAT) reduces arterial blood pressure (BP) by inhibition of the sympathetic nervous system. The objective of this study was to evaluate whether BAT influences metabolic state in patients with resistant hypertension.

METHODS

Thirty patients with resistant hypertension (10 with known diabetes mellitus) were prospectively included into this study. Blood pressure, BMI, weight, fasting glucose, insulin, C-peptide, hemoglobin A1c, HOMA-IR, HOMA-β, ISQuickI, and glucose levels during oral glucose tolerance test were measured at baseline and 6 months after BAT activation.

RESULTS

Fasting glucose was significantly reduced after 6 months of BAT, whereas mean 2-h glucose levels during oral glucose tolerance test, fasting insulin levels, C-peptide levels, hemoglobin A1c, HOMA-IR, HOMA-β, ISQuickI, weight, and BMI remained unchanged.

CONCLUSION

Despite improvement in fasting glucose, BAT exerts neither sustained additional beneficial effects nor an impairment of metabolic state. Thus, chronic BAT might be an effective interventional method to reduce BP without metabolic disadvantages.

Coefficient of variation of R-R interval closely correlates with glycemic variability assessed by continuous glucose monitoring in insulin-depleted patients with type 1 diabetes

AIMS

In type 1 diabetic patients, insulin secretory capacity, meals and physical activity correlate with glycemic variability. Autonomic function associated with gastrointestinal motility and counterregulatory hormone secretion is another candidate which correlates with glucose variability. The aim of this study is to clarify a new clinical parameter associated with glycemic variability in insulin-depleted patients with type 1 diabetes.

METHODS

We studied 31 inpatients with type 1 diabetes. We evaluated glycemic variability calculated by continuous glucose monitoring, clinical parameters and the coefficient of variation of R-R interval (CVR-R). Glycemic variability was also assessed during the daytime and nighttime.

RESULTS

The CVR-R showed a significant negative correlation with the whole-day standard deviation (SD) (r = -0.50, p = 0.007), mean amplitude of glycemic excursions (MAGE) (r = -0.47, p=0.011), M-value (r = -0.38, p = 0.048) and mean of daily differences (MODD) (r = -0.59, p = 0.001). The CVR-R also showed a significant negative correlation with the nighttime SD (r = -0.59, p = 0.001), MAGE (r = -0.47, p=0.011), M-value (r = -0.53, p = 0.004) and MODD (r = -0.65, p = 0.0003). And furthermore, the CVR-R also showed a significant negative correlation with the daytime SD (r = -0.44, p = 0.019) and MAGE (r = -0.50, p = 0.006), but not with the daytime M-value or MODD. The nighttime SD was significantly higher in patients with diabetic polyneuropathy than in patients without it (p = 0.016), while the CVR-R was significantly lower in patients with polyneuropathy than in patients without it (p = 0.009).

CONCLUSIONS

CVR-R is closely correlated with glycemic variability, especially during nighttime, in insulin-depleted patients with type 1 diabetes. Measuring CVR-R may help us to presume the degree of glycemic variability in those patients.

Physical activity and type 1 diabetes: time for a rewire?

While being physically active bestows many health benefits on individuals with type 1 diabetes, their overall blood glucose control is not enhanced without an effective balance of insulin dosing and food intake to maintain euglycemia before, during, and after exercise of all types. At present, a number of technological advances are already available to insulin users who desire to be physically active with optimal blood glucose control, although a number of limitations to those devices remain. In addition to continued improvements to existing technologies and introduction of new ones, finding ways to integrate all of the available data to optimize blood glucose control and performance during and following exercise will likely involve development of "smart" calculators, enhanced closed-loop systems that are able to use additional inputs and learn, and social aspects that allow devices to meet the needs of the users.

Evidence of altered autonomic cardiac regulation in breast cancer survivors

PURPOSE

Surgery and adjuvant therapy improved prognosis of breast cancer survivors. This improvement risks being offset by potential late-occurring cardiovascular toxicity of oncologic treatment and increased cardiometabolic risk profile associated with lifestyle changes. We address the hypothesis that in breast cancer survivors, multiple functional alterations might define a phenotype, characterized by vagal impairment, diminished aerobic fitness, increased metabolic risk, and reduced wellbeing.

METHODS

We studied 171 sedentary asymptomatic women (106 cancer survivor-65 controls) of similar age (53 ± 8.6; 51 ± 8.1 years). Autonomic regulation was evaluated by autoregressive spectral analysis of R wave to R wave (RR) interval and systolic arterial pressure variability. Aerobic fitness was directly assessed by cardiopulmonary exercise test. Body mass index (BMI) and waist circumference served as proxies of metabolism. Fatigue and stress-related symptoms were evaluated with validated questionnaire.

RESULTS

Patients showed significantly smaller total RR variance (1644 ± 2363 vs. 2302 ± 1561 msec2), smaller absolute power of low frequency (LF) (386 ± 745 vs. 810 ± 1300 msec2) and high frequency (HF) (485 ± 1202 vs. 582 ± 555 msec2) of RR interval variability and smaller spontaneous baroreflex sensitivity (15.0 ± 8.9 vs. 21.9 ± 10 msec/mmHg), suggesting vagal impairment. VO2 peak and O2 pulse were lower in cancer survivors than in controls. Fatigue and stress-related somatic symptoms scores were higher, as was BMI and waist circumference.

CONCLUSION

Breast cancer survivors show multiple dysfunctions: vagal impairment, lower aerobic fitness, signs of altered metabolism, and higher perception of fatigue.

IMPLICATIONS FOR CANCER SURVIVORS

We propose that the concept of clinical phenotype, which may accommodate multiple functional disturbances, might be useful in long-term personalized prevention programs for breast cancer survivors.

Autonomic nervous system dysregulation in irritable bowel syndrome

BACKGROUND

Autonomic nervous system (ANS) regulation may be altered in functional diseases, including irritable bowel syndrome (IBS), but published data are not clear to date. The aim of the study was to analyze ANS function in IBS subjects classified by Rome III criteria and healthy controls using standardized technique.

METHODS

ANS activity was evaluated by autoregressive spectral analysis of RR interval and systolic arterial pressure variabilities, to obtain indices of sympatho-vagal modulation of the heart and of spontaneous cardiac baroreflex (α index). A symptom list was used to score 18 somatic complaints (score 0-180) (4SQ). Fatigue and stress were assessed through the use of a global scoring index (0-10).

KEY RESULTS

We enrolled 41 IBS subjects (29 F, age 40 ± 2 years) and 42 healthy matched controls. Heart rate was higher in IBS than control subjects (69 ± 2 vs 61 ± 1; p < 0.001). The total variance of RR interval variability, and α index, were significantly lower in IBS compared to controls (1983.12 ± 384.64 ms(2) vs 4184.55 ± 649.59 ms(2) ; 18.1 ± 2 ms/mmHg vs 29 ± 3 ms/mmHg; p < 0.01). The α index results showed an inverse correlation with stress scores and somatic symptoms.

CONCLUSIONS & INFERENCES

IBS subjects display a significant reduction in α index, an established marker of cardiac baroreflex. ANS dysfunction appears to be involved in the pathophysiology of IBS and its assessment may open new perspectives for clinical management of patients suffering from IBS.

Influence of lifestyle on the course of type 1 diabetes mellitus

Type 1 diabetes (T1DM) is an autoimmune disease that requires insulin treatment from the time of diagnosis. Its clinical course depends on both genetic and environmental factors, and the lifestyle of a patient modulates their interaction. The evidence about the influence of lifestyle on the course of T1DM is increasing. In this paper, we present evidence on the relationship between lifestyle parameters and diabetes-related outcomes. We discuss the most commonly addressed factors associated with lifestyle, such as physical activity, nutrition and smoking, and those with sparse evidence in T1DM, such as socioeconomic status, sleep duration, psychological stress and illicit drugs intake.

Organ-based response to exercise in type 1 diabetes

While significant research has clearly identified sedentary behavior as a risk factor for type 2 diabetes and its subsequent complications, the concept that inactivity could be linked to the complications associated with type 1 diabetes (T1D) remains underappreciated. This paper summarizes the known effects of exercise on T1D at the tissue level and focuses on the pancreas, bone, the cardiovascular system, the kidneys, skeletal muscle, and nerves. When possible, the molecular mechanisms underlying the benefits of exercise for T1D are elucidated. The general benefits of increased activity on health and the barriers to increased exercise specific to people with T1D are discussed.