Exercise and diabetes

A comparative analysis of energy expenditure and substrate metabolism in male university students with overweight/obesity: Tabata vs HIIT and MICT

Introduction

Exploring the energy expenditure and substrate metabolism data during exercise, 10-minute recovery, and 20-minute recovery phases in Tabata, HIIT(High-Intensity Interval Training), and MICT(Moderate-Intensity Continuous Training). This study explores the scientific aspects of weight reduction strategies, examining energy expenditure and substrate metabolism from various training perspectives. The aim is to establish a theoretical foundation for tailoring targeted exercise plans for individuals within the population with overweight/obesity.

Methods

This study used an experimental design with fifteen male university students with overweight/obesity. Participants underwent random testing with Tabata, HIIT, and MICT. Tabata involved eight sets of 20 seconds exercise and 10 seconds rest, totaling 4 minutes. HIIT included four sets of power cycling: 3 minutes at 80% VO2max intensity followed by 2 minutes at 20% VO2max. MICT comprised 30 minutes of exercise at 50% VO2max intensity. Gas metabolism indices were continuously measured. Subsequently, fat and glucose oxidation rates, along with energy expenditure, were calculated for each exercise type.

Results

During both the exercise and recovery phases, the Tabata group exhibited a significantly higher fat oxidation rate of (0.27 ± 0.03 g/min) compared to the HIIT group (0.20 ± 0.04 g/min, p<0.05) and the MICT group (0.20 ± 0.03g/min, p<0.001). No significant difference was observed between the HIIT and MICT groups (p=0.854). In terms of energy expenditure rate, the Tabata group maintained a substantially elevated level at 5.76 ± 0.74kcal/min compared to the HIIT group (4.81 ± 0.25kcal/min, p<0.01) and the MICT group (3.45 ± 0.25kcal/min, p<0.001). Additionally, the energy expenditure rate of the HIIT group surpassed that of the MICT group significantly (p<0.001).

Conclusion

The study finds that male college students with overweight/obesity in both exercise and recovery, Tabata group has lower fat and glucose oxidation rates, and energy expenditure compared to HIIT and MICT groups. However, over the entire process, Tabata still exhibits significantly higher rates in these aspects than HIIT and MICT. Despite a shorter exercise duration, Tabata shows a noticeable "time-efficiency" advantage. Tabata can be used as an efficient short-term weight loss exercise program for male college students with overweight/obesity.

miR-34a/SIRT1/HIF-1α axis is involved in cardiac angiogenesis of type 2 diabetic rats: The protective effect of sodium butyrate combined with treadmill exercise

Type 2 diabetes mellitus (T2DM) is one of the most common metabolic disorders worldwide. Recent research has indicated that sodium butyrate (NaB) affects glucose metabolism and exercise has an anti-hyperglycemic effect in diabetes. This study aimed to evaluate the effects of NaB and treadmill exercise on heart angiogenesis through the miR-34a/SIRT1/FOXO1-HIF-1α pathway. Diabetic animals received NaB (400 mg/kg daily, orally) and treadmill exercise for 6 weeks. The effect of NaB and treadmill exercise, alone or combined, on miR-34a expression, SIRT1, FOXO1, HIF-1α levels, and angiogenesis in diabetic heart tissue was measured. Diabetes caused increased miR-34a (p < 0.01) and FOXO1 (p < 0.001) expression levels. Also, SIRT1 (p < 0.001) and HIF-1α (not significant) expression levels were reduced in diabetic rats. NaB and treadmill exercise decreased miR-34a (respectively p < 0.05 and not significant) and FOXO1 (both p < 0.001) expression levels and improved SIRT1 (both not significant) and HIF-1α (respectively p < 0.01 and p < 0.001) levels. Also, NaB combined with treadmill exercise decreased miR-34a (p < 0.001) and FOXO1 (p < 0.001) expression levels, and elevated SIRT1 (p < 0.05) and HIF-1α (p < 0.001) levels in comparison with the diabetic group. NaB and treadmill exercises modulate the expression of miR-34a and the levels of SIRT1, FOXO1, and HIF-1α proteins, thus increasing angiogenesis in the heart tissue of diabetic rats. It can be concluded that NaB and treadmill exercise, alone or combined, may be useful in the treatment of diabetes through the miR-34a/SIRT1/FOXO1-HIF-1α pathway.

Considerations in the Care of Athletes With Type 1 Diabetes Mellitus

Type 1 diabetes mellitus is an autoimmune disease caused by affected individuals’ autoimmune response to their own pancreatic beta-cell. It affects millions of people worldwide. Exercise has numerous health and social benefits for patients with type 1 diabetes mellitus; however, careful management of blood glucose is crucial to minimize the risk of hypoglycemia and hyperglycemia. Anaerobic and aerobic exercises cause different glycemic responses during and after exercise, each of which will affect athletes’ ability to reach their target blood glucose ranges. The optimization of the patient’s macronutrient consumption, especially carbohydrates, the dosage of basal and short-acting insulin, and the frequent monitoring of blood glucose, will enable athletes to perform at peak levels while reducing their risk of dysglycemia. Despite best efforts, hypoglycemia can occur. Recognition of symptoms and rapid treatment with either fast-acting carbohydrates or glucagon is important. Continuous glucose monitoring devices have become more widely used in preventing hypoglycemia.

Diabetes and Composition of Weight Lifting and Cardio in Exercise

The prevalence of type-2 diabetes(T2D) has increased globally. This has led to greater mortality, morbidity and disability in the general population. It is thus crucial to identify methods to prevent its onset among the healthy, and to also discover solutions to adequately manage the complications among those affected. Most research in this area has focused on the role of diet and exercise. More recently, different exercise types and their relationship with T2D has received considerable attention. In our work, we investigate the association between T2D (primary outcome) and two types of exercises: cardio (CR) and weight lifting (WL). Specifically, the relationship between duration of time spent in the two exercises and the odds of T2D is explored. Data are obtained from the Behavioural Risk Factor Surveillance System (BRFSS) survey, USA. Three ethnic populations are considered: White American, Black American and Hispanic American. Both WL and CR are found to be associated with negative log-odds of diabetes across all three ethnicities (WL: p <; 0.0001 and CR: p=0.00431). The association between WL and T2D is found to be modified for females (interaction-term coefficient: -0.096 (p=0.0115)).

Determinants of Diabetic Nephropathy among Diabetic Patients in General Public Hospitals of Tigray, Ethiopia, 2018/19

BACKGROUND

Diabetic nephropathy is real damage resulting from having uncontrolled diabetes mellitus. Unmanaged diabetic nephropathy is one of the most leading causes of kidney failure. There is a scarcity of information on the determinants of diabetic nephropathy among diabetes mellitus patients in Ethiopia. Identification of the determinants can help devise a strategy to properly address the disease and its consequences. Therefore, this study was designed to assess the determinants of diabetic nephropathy among diabetes mellitus patients.

METHODS

Unmatched case-control study design with 168 cases and 672 controls with a mean age of 45.18 and 62.12, respectively, participated in the study. An interviewer-administered questionnaire was employed for data collection, and a systematic sampling technique was used to select the study participants. Data were entered into Epi data and exported to SPSS for data clarification and analysis. Binary logistic regression analysis was carried out to check the level of association between diabetic nephropathy and the independent variables.

RESULTS

Comorbidity (AOR: 4.96 at 95 CI: 1.77-13.87), hypertension (AOR: 6.33, 95% CI: 2.51-16.02), poor glycemic control (AOR: 3.27, 95% CI: 1.31, 8.21), age (AOR: 1.14, 95%: 1.09-1.19), duration with diabetes mellitus since diagnosis (AOR: 1.83, 95 CI: 1.62-2.06), and nonadherence to diabetic medication (AOR: 3.3, 95% CI: 1.34, 8.15), diet (AOR: 5.96, 95%: 1.92-18.54), and exercise (AOR: 5.60, 95% CI: 1.94-16.21) were the determinants of diabetic nephropathy.

CONCLUSION

Adherence to medication, diet, and exercise should be empowered to achieve glycemic control and to prevent diabetic nephropathy. More attention has to be also given for old aged diabetic patients, long duration since diagnosis of diabetes mellitus, hypertension, and other comorbidities.

Effectiveness of a 12-Week Physical Exercise Program on Lower-Limb Malalignment in School-age Rugby: A Randomized Clinical Trial

OBJECTIVE

We sought to assess the effectiveness of 12 weeks of a physical exercise program (PEP) in child rugby players with lower-limb overpronation during gait.

METHODS

This was a randomized clinical trial. A total of 123 young athletes (mean ± standard deviation age, 10.35 ± 1.22 years) were evaluated, 20 of whom had lower-limb overpronation (n = 40 extremities). Participants were randomly assigned to 2 groups: the experimental group, who performed their normal training and a PEP for 12 weeks, and the control group, who continued with their normal training for the same time. The PEP was focused on stretching the hypertonic muscle and potentiating the weakened muscles of the lower body. All participants underwent biomechanical analysis including the Helbing angle, the femorotibial angle, and the Fick angle in both limbs.

RESULTS

All participants (n = 20) completed the study. Baseline measurements showed no significant differences between groups in any of the variables tested. After 12 weeks, there were significant differences between groups (P < .001 for all angles). No improvement was found in the control group; however, meaningful improvement was found in all variables in the experimental group: Helbing angle (175°, P < .001, effect size [ES] = 1.94), femorotibial angle (173°, P < .001, ES = 1.77), Fick angle (12°, P < .001, ES = 1.55). The number needed to treat was 2 for femorotibial angle and Helbing angle, and 3 for Fick angle.

CONCLUSION

A 12-week PEP produced significant improvements in these 3 biomechanical variables. We also conclude that young athletes with a pathological gait pattern reached a normal gait pattern.

Effectiveness of an education intervention associated with an exercise program in improving disease-related knowledge and health behaviours among diabetes patients

OBJECTIVE

to assess the effectiveness of an education intervention associated with an exercise program in improving knowledge and health behaviours among diabetes patients.

METHODS

Diabetes and prediabetes patients were exposed to an evidence- and theoretically-based comprehensive education intervention over 24 weeks. Patients completed surveys assessing knowledge, physical activity, food intake, self-efficacy, and health literacy. Functional capacity was measured by oxygen uptake. All outcomes were assessed pre- and post-CR. Satisfaction about the education provided was assessed at post-CR. Paired t-tests, Pearson correlation coefficients, and linear regression models were computed to investigate the effectiveness of this intervention.

RESULTS

84 patients consented to participate, of which 47(56.0%) completed post-CR assessments. There was a significant improvement in patients' overall knowledge pre- to post-CR, as well as in physical activity, food intake, self-efficacy, and health literacy (p < 0.05). Peak VO₂ has clinically significant improved. Results showed a low significant positive correlation was between post-CR knowledge and food intake(r = 0.297;p = 0.04). Linear regression analysis revealed that age(B=-0.051; p = 0.01) was influential in changing post-CR knowledge.

CONCLUSION

The benefits of an education intervention designed for diabetes and prediabetes patients associated with an exercise program have been supported.

PRACTICE IMPLICATIONS

This work shows one effective education strategy taken in place that can be replicated in different settings.

HbA1c AND BLOOD PRESSURE MEASUREMENTS: RELATION WITH GENDER, BODY MASS INDEX, STUDY FIELD, AND LIFESTYLE IN LEBANESE STUDENTS

Objective: The purpose of this study is to determine the prevalence of prediabetes/diabetes in Lebanese university students and to examine the relationship between both hemoglobin A1c (HbA1c) and blood pressure (BP) and gender, body mass index (BMI), study field, and lifestyle factors. Methods: This cross-sectional study was carried out at the Saint-Joseph University of Beirut. A total of 603 students aged 18 to 25 years were recruited from both the medical science campus (MSC) and the social science campus (SSC) between January, 2016, and May, 2018. Waist circumference (WC), BMI, and BP were determined for each student and HbA1c was measured using the Siemens vintage DCA device. Participants completed a self-administered questionnaire about their eating habits and level of physical activity. Results: The mean age of the population was 20.31 ± 1.76 years. The percentage of participants recruited from the MSC was 59.2%. The prevalence of prediabetes was 2.5%. Lower BMI, WC, and HbA1c values, and higher diastolic BP (DBP) were found in MSC students compared to SSC ones. HbA1c, systolic BP (SBP), and DBP were correlated with BMI (P = .02, P<.0001, and P = .017, respectively). HbA1c was not associated with eating habits or physical activity. DBP was inversely associated with physical activity (P = .002), while SBP was positively associated with fast food consumption (P = .003). Conclusion: The present study shows a low prevalence of prediabetes in Lebanese students. BMI and the study field are the main factors predicting HbA1c and BP. Further studies are needed to extrapolate our results to the overall young Lebanese population. Abbreviations: ADA = American Diabetes Association; BMI = body mass index; BP = blood pressure; DBP = diastolic blood pressure; HbA1c = hemoglobin A1c; HTN = hypertension; MSC = medical science campus; SBP = systolic blood pressure; SSC = social science campus; T2D = type 2 diabetes; US = United States; USJ = Saint-Joseph University; WC = waist circumference.

Exercise Training Attenuates the Development of Cardiac Autonomic Dysfunction in Diabetic Rats

BACKGROUND/AIM

Exercise training usually complements pharmacological therapy of type 1 diabetes mellitus, however, little is known about its impact on cardiac autonomic neuropathy. Our aim was to evaluate the impact of exercise on electrocardiographic parameters and heart rate variability in diabetic rats.

MATERIALS AND METHODS

Wistar rats were randomly assigned to four groups (n=12): Sedentary control (SC), sedentary diabetic (SD), exercise control (EC), and exercise diabetic (ED). Diabetes was induced by a single intraperitoneal injection of streptozotocin (45 mg/kg). Exercise groups underwent 8 weeks of training on a treadmill. At the end of the study, echocardiography was performed and continuous electrocardiographic recording was obtained by intra-abdominally implanted telemetric devices. Diabetes induction significantly reduced the heart rate and increased the blood glucose level (p<0.001) and R-wave amplitude (p<0.05). Frequency-domain spectral variables were also analyzed. The SD group had a significantly lower absolute high-frequency component (p<0.05) and higher normalized low-frequency component, as well as low-frequency power divided by the high-frequency power ratio when compared to the SC and EC groups (p<0.05). All these diabetes-related adverse changes in heart rate variability parameters were significantly reversed by exercise training (p<0.05). Overall, our study shows that early initiation of systemic exercise training prevents the development of cardiac autonomic neuropathy in rats with type 1 diabetes mellitus, by favorable change in the balance between parasympathetic and sympathetic activity.

The Effect of Garlic and Voluntary Exercise on Cardiac Angiogenesis in Diabetes: The Role of MiR-126 and MiR-210

BACKGROUND

Diabetes mellitus (DM) is one of the major risk factors for cardiovascular disease, leading to endothelial dysfunction and angiogenesis impairment . MiR-126 and miR-210 support angiogenic response in endothelial cells.

OBJECTIVE

The present study sought to explore the effect of garlic and voluntary exercise, alone or together, on miR-126 and miR-210 expressions and cardiac angiogenesis in rats with type 1 diabetes.

METHODS

Male Wistar rats were divided into five groups (n = 7): Control, Diabetes, Diabetes+Garlic, Diabetes+Exercise, and Diabetes+Garlic+Exercise. Diabetes was induced in the animals by streptozotocin (ip, 50 mg/kg). The rats were then fed raw fresh garlic homogenate (250 mg/kg) or were subjected to voluntary exercise, or to combined garlic and voluntary exercise for 6 weeks. MiR-126 and miR-210 expressions in the myocardium were determined by real time PCR, and the serum lipid profile was measured by enzymatic kits. Angiogenesis was evaluated by immunostaining for PECAM-1/ CD31 in the myocardium.

RESULTS

Diabetes reduced both cardiac miR-126 expression and angiogenesis (p < 0.05). On the other hand, there was a miR-210 expression increase in the myocardium of diabetic animals (p < 0.001). However, those effects reversed either with garlic or voluntary exercise (p < 0.01). Moreover, treating diabetic rats with garlic and voluntary exercise combined had an additional effect on the expressions of miR-126 and miR-210 (p < 0.001). Furthermore, both voluntary exercise and garlic significantly improved serum lipid profiles (p < 0.001).

CONCLUSION

The induction of diabetes decreased angiogenesis in the myocardium, whereas our treatment using long-term voluntary exercise and garlic improved myocardial angiogenesis. These changes were possibly owing to the enhancement of myocardial miR-126 and miR-210 expressions.

Review of the literature examining the association between physical activity and retinopathy

The main aim of this review was to evaluate the association between physical activity and retinopathy. Secondary aims included evaluating the association between sedentary behavior and retinopathy, and evaluating the association between physical activity/sedentary behavior on health outcomes among patients with existing retinopathy. Twenty-one articles met our criteria for inclusion in this review. Among the 19 studies evaluating the main aim (physical activity and retinopathy), 53% (n = 10/19) demonstrated evidence of a favorable (inverse) association between physical activity and retinopathy, 42% (n = 8/19) reported a null association physical activity and retinopathy, and 5% (n = 1/19) presented evidence for a detrimental association between physical activity and retinopathy. Regarding the secondary aims, one study demonstrated a detrimental association between sedentary behavior and retinopathy. Similarly, one study demonstrated that physical activity was protective against early mortality among those with mild retinopathy. This review identifies an 'indeterminate' association between physical activity and retinopathy. Too few studies evaluated the association between sedentary behavior and retinopathy or the effects of physical activity on health outcomes among those with existing retinopathy.

Hypoglycemia during moderate intensity exercise reduces counterregulatory responses to subsequent hypoglycemia

Hypoglycemia, which occurs commonly during and following exercise in people with diabetes, is thought to be due to attenuated counterregulation in the setting of therapeutic insulin excess. To better understand the pathophysiology of counterregulation, we aimed to determine if dextrose administration to maintain euglycemia during moderate intensity exercise alters the attenuation of counterregulatory responses to subsequent hypoglycemia in healthy adults. Counterregulatory responses to hypoglycemia were assessed in 18 healthy adults after bed rest and following exercise with (n = 9) and without (n = 9) dextrose infusion. Responses were measured during a stepped euglycemic‐hypoglycemic clamp 24 h after either bed rest or two 90‐min bouts of exercise at 70% peak oxygen uptake. Hypoglycemia occurred during the second bout of exercise without dextrose infusion. Plasma glucagon and epinephrine responses to stepped hypoglycemia after antecedent exercise without dextrose infusion were significantly lower at the 45 mg/dL glycemic level compared to after bed rest. However, no attenuation of the counterregulatory responses to hypoglycemia was evident after antecedent exercise when dextrose was infused. This study suggests that the attenuation of the counterregulatory responses during hypoglycemia after exercise is likely due to the hypoglycemia that occurs during moderate prolonged exercise and not solely due to exercise or its intensity.

TREAD: TReatment with Exercise Augmentation for Depression: study rationale and design

Background Despite recent advancements in the pharmacological treatment of major depressive disorder (MDD), over half of patients who receive treatment with antidepressant medication do not achieve full remission of symptoms. There is evidence that exercise can reduce depressive symptomatology when used as a treatment for MDD. However, no randomized controlled trials have evaluated exercise as an augmentation strategy for patients with carefully diagnosed MDD who remain symptomatic following an adequate acute phase trial of antidepressant therapy.

Purpose TReatment with Exercise Augmentation for Depression (TREAD) is an NIMH-funded, randomized, controlled trial designed to assess the relative efficacy of two doses of aerobic exercise to augment selective serotonin reuptake inhibitor (SSRI) treatment of MDD.

Methods The TREAD study includes 12 weeks of acute phase treatment with a 12-week post-treatment follow-up. In addition to looking at change in depressive symptoms as a primary outcome, it also includes comprehensive assessment of psychosocial function and treatment adherence.

Results This paper reviews the rationale and design of TREAD and illustrates how we address several key issues in contemporary patient-oriented research on MDD: 1) the use of augmentation strategies in the treatment of depressive disorders in general, 2) the use of non-pharmacological strategies in the treatment of depressive disorders, 3) the considerations of designing a well-controlled trial using two active treatment groups, and 4) the implementation of an adherence program for the use of exercise as a treatment strategy.

Conclusions The TREAD study is uniquely designed to overcome sources of potential bias and threats to internal and external validity that have limited prior research on the mental health effects of exercise. The study is facilitated by the development of a multidisciplinary research team that includes experts in both depression treatment and exercise physiology, as well as other related fields.

High Intensity Aerobic Exercise Training Improves Deficits of Cardiovascular Autonomic Function in a Rat Model of Type 1 Diabetes Mellitus with Moderate Hyperglycemia

Indices of cardiovascular autonomic neuropathy (CAN) in experimental models of Type 1 diabetes mellitus (T1DM) are often contrary to clinical data. Here, we investigated whether a relatable insulin-treated model of T1DM would induce deficits in cardiovascular (CV) autonomic function more reflective of clinical results and if exercise training could prevent those deficits. Sixty-four rats were divided into four groups: sedentary control (C), sedentary T1DM (D), control exercise (CX), or T1DM exercise (DX). Diabetes was induced via multiple low-dose injections of streptozotocin and blood glucose was maintained at moderate hyperglycemia (9-17 mM) through insulin supplementation. Exercise training consisted of daily treadmill running for 10 weeks. Compared to C, D had blunted baroreflex sensitivity, increased vascular sympathetic tone, increased serum neuropeptide Y (NPY), and decreased intrinsic heart rate. In contrast, DX differed from D in all measures of CAN (except NPY), including heart rate variability. These findings demonstrate that this T1DM model elicits deficits and exercise-mediated improvements to CV autonomic function which are reflective of clinical T1DM.

Classification of Physical Activity: Information to Artificial Pancreas Control Systems in Real Time

Physical activity has a wide range of effects on glucose concentrations in type 1 diabetes (T1D) depending on the type (ie, aerobic, anaerobic, mixed) and duration of activity performed. This variability in glucose responses to physical activity makes the development of artificial pancreas (AP) systems challenging. Automatic detection of exercise type and intensity, and its classification as aerobic or anaerobic would provide valuable information to AP control algorithms. This can be achieved by using a multivariable AP approach where biometric variables are measured and reported to the AP at high frequency. We developed a classification system that identifies, in real time, the exercise intensity and its reliance on aerobic or anaerobic metabolism and tested this approach using clinical data collected from 5 persons with T1D and 3 individuals without T1D in a controlled laboratory setting using a variety of common types of physical activity. The classifier had an average sensitivity of 98.7% for physiological data collected over a range of exercise modalities and intensities in these subjects. The classifier will be added as a new module to the integrated multivariable adaptive AP system to enable the detection of aerobic and anaerobic exercise for enhancing the accuracy of insulin infusion strategies during and after exercise.

An observational cohort study to assess glycosylated hemoglobin screening for elective surgical patients

INTRODUCTION

Uncontrolled blood glucose is associated with a higher incidence of surgical site infections, greater utilization of resources, and increased mortality. Preoperative screening for diabetes in elective surgical patients is not routinely performed. The purpose of this study was to examine blood glucose control in a preoperative surgical population.

METHODS

Following ethics approval, adults presenting to the pre-surgical screening clinic in preparation for elective surgery were recruited. Data collection included a self-administered questionnaire on diabetic risk factors and blood glucose testing, including glycosylated hemoglobin (HbA1c). Descriptive analyses were conducted.

RESULTS

Seventy of the 402 participants (17.4%) had a previous diagnosis of diabetes (diabetics). Among those without a history of diabetes (n = 332 non-diabetics), 23.2% (n = 77) were considered very high risk for diabetes (HbA1c = 6.0-6.4%), and 3.9% (n = 13) had a provisional diagnosis of diabetes (HbA1c ≥ 6.5%). Fifty-six percent (n = 39/70) of diabetics had suboptimal glycemic control (HbA1c > 7.0%), and 51.3% (n = 20/39) of this subgroup presumed their blood sugars were reasonably or very well controlled. Fifteen percent (n = 2/13) of patients with a provisional diagnosis of diabetes (HbA1c ≥ 6.5%) had an elevated random blood sugar (RBS) (≥ 11.1 mmol·L(-1)), while 67% (n = 8/12) had an elevated fasting blood sugar (FBS) (≥ 7.0 mmol·L(-1)). Forty-two percent (n = 16/38) of suboptimally controlled diabetics (HbA1c > 7.0%) had an elevated RBS (≥ 11.1 mmol·L(-1)), and 86% (n = 31/36) had an elevated FBS (≥ 7.0 mmol·L(-1)).

DISCUSSION

Many elective surgical patients are at risk for unrecognized postoperative hyperglycemia and associated adverse outcomes. Random blood sugar testing has limited value and HbA1c may be a more appropriate test for the preoperative assessment of diabetic patients.

Hypoglycemia in patients with type 1 diabetes: epidemiology, pathogenesis, and prevention

Hypoglycemia is uncommon in the general, nondiabetic population but occurs frequently in persons with diabetes treated with insulin or insulin secretagogues. Thus, iatrogenic hypoglycemia explains the majority of cases among persons with type 1 diabetes (T1DM). Since T1DM is characterized by absolute insulin dependence, the current imperfections in insulin replacement therapies often lead to a mismatch between caloric supply and circulating insulin levels, thus increasing the risk for glycemic fluctuations. Hypoglycemia is the limiting factor to excellent glycemic control in insulin-treated subjects. Intensification of glycemic control was associated with a 300 % increase in the rate of hypoglycemia in the Diabetes Control and Complications Trial. Recent measurements using continuous glucose monitoring reveal an alarming rate of daytime and nocturnal episodes of hypoglycemia in patients with T1DM. Etiological factors underlying hypoglycemia in T1DM include predictable triggers (skipped meals, exercise, insulin over dosage) as well as defective counterregulation, a component of hypoglycemia-associated autonomic failure.

Hypoglycemia and diabetes: a report of a workgroup of the American Diabetes Association and the Endocrine Society

OBJECTIVE

To review the evidence about the impact of hypoglycemia on patients with diabetes that has become available since the past reviews of this subject by the American Diabetes Association and The Endocrine Society and to provide guidance about how this new information should be incorporated into clinical practice.

PARTICIPANTS

Five members of the American Diabetes Association and five members of The Endocrine Society with expertise in different aspects of hypoglycemia were invited by the Chair, who is a member of both, to participate in a planning conference call and a 2-day meeting that was also attended by staff from both organizations. Subsequent communications took place via e-mail and phone calls. The writing group consisted of those invitees who participated in the writing of the manuscript. The workgroup meeting was supported by educational grants to the American Diabetes Association from Lilly USA, LLC and Novo Nordisk and sponsorship to the American Diabetes Association from Sanofi. The sponsors had no input into the development of or content of the report.

EVIDENCE

The writing group considered data from recent clinical trials and other studies to update the prior workgroup report. Unpublished data were not used. Expert opinion was used to develop some conclusions.

CONSENSUS PROCESS

Consensus was achieved by group discussion during conference calls and face-to-face meetings, as well as by iterative revisions of the written document. The document was reviewed and approved by the American Diabetes Association's Professional Practice Committee in October 2012 and approved by the Executive Committee of the Board of Directors in November 2012 and was reviewed and approved by The Endocrine Society's Clinical Affairs Core Committee in October 2012 and by Council in November 2012.

CONCLUSIONS

The workgroup reconfirmed the previous definitions of hypoglycemia in diabetes, reviewed the implications of hypoglycemia on both short- and long-term outcomes, considered the implications of hypoglycemia on treatment outcomes, presented strategies to prevent hypoglycemia, and identified knowledge gaps that should be addressed by future research. In addition, tools for patients to report hypoglycemia at each visit and for clinicians to document counseling are provided.

Hypoglycemia and diabetes: a report of a workgroup of the American Diabetes Association and the Endocrine Society

OBJECTIVE

To review the evidence about the impact of hypoglycemia on patients with diabetes that has become available since the past reviews of this subject by the American Diabetes Association and The Endocrine Society and to provide guidance about how this new information should be incorporated into clinical practice.

PARTICIPANTS

Five members of the American Diabetes Association and five members of The Endocrine Society with expertise in different aspects of hypoglycemia were invited by the Chair, who is a member of both, to participate in a planning conference call and a 2-day meeting that was also attended by staff from both organizations. Subsequent communications took place via e-mail and phone calls. The writing group consisted of those invitees who participated in the writing of the manuscript. The workgroup meeting was supported by educational grants to the American Diabetes Association from Lilly USA, LLC and Novo Nordisk and sponsorship to the American Diabetes Association from Sanofi. The sponsors had no input into the development of or content of the report.

EVIDENCE

The writing group considered data from recent clinical trials and other studies to update the prior workgroup report. Unpublished data were not used. Expert opinion was used to develop some conclusions.

CONSENSUS PROCESS

Consensus was achieved by group discussion during conference calls and face-to-face meetings, as well as by iterative revisions of the written document. The document was reviewed and approved by the American Diabetes Association's Professional Practice Committee in October 2012 and approved by the Executive Committee of the Board of Directors in November 2012 and was reviewed and approved by The Endocrine Society's Clinical Affairs Core Committee in October 2012 and by Council in November 2012.

CONCLUSIONS

The workgroup reconfirmed the previous definitions of hypoglycemia in diabetes, reviewed the implications of hypoglycemia on both short- and long-term outcomes, considered the implications of hypoglycemia on treatment outcomes, presented strategies to prevent hypoglycemia, and identified knowledge gaps that should be addressed by future research. In addition, tools for patients to report hypoglycemia at each visit and for clinicians to document counseling are provided.

Effects of exercise training on excitation-contraction coupling and related mRNA expression in hearts of Goto-Kakizaki type 2 diabetic rats

Although, several novel forms of intervention aiming at newly identified therapeutic targets are currently being developed for diabetes mellitus (DM), it is well established that physical exercise continues to be one of the most valuable forms of non-pharmacological therapy. The aim of the study was to investigate the effects of exercise training on excitation-contraction coupling and related gene expression in the Goto-Kakizaki (GK) type 2 diabetic rat heart and whether exercise is able to reverse diabetes-induced changes in excitation-contraction coupling and gene expression. Experiments were performed in GK and control rats aged 10-11 months following 2-3 months of treadmill exercise training. Shortening, [Ca(2+)]i and L-type Ca(2+) current were measured in ventricular myocytes with video edge detection, fluorescence photometry and whole cell patch clamp techniques, respectively. Expression of mRNA was assessed in ventricular muscle with real-time RT-PCR. Amplitude of shortening, Ca(2+) transients and L-type Ca(2+) current were not significantly altered in ventricular myocytes from GK sedentary compared to control sedentary rats or by exercise training. Expression of mRNA encoding Tpm2, Gja4, Atp1b1, Cacna1g, Cacnb2, Hcn2, Kcna3 and Kcne1 were up-regulated and Gja1, Kcnj2 and Kcnk3 were down-regulated in hearts of sedentary GK rats compared to sedentary controls. Gja1, Cav3 and Kcnk3 were up-regulated and Hcn2 was down-regulated in hearts of exercise trained GK compared to sedentary GK controls. Ventricular myocyte shortening and Ca(2+) transport were generally well preserved despite alterations in the profile of expression of mRNA encoding a variety of cardiac muscle proteins in the adult exercise trained GK diabetic rat heart.

Poor glycaemic control and arrhythmias

OBJECTIVE

To evaluate number, type, and complexity of arrhythmias in diabetics compared with controls and, among diabetics, comparing good glycaemic control (GGC) and poor glycaemic control (PGC) patients.

METHODS

We compared Ambulatory Electrocardiogram recordings of 92 diabetics and 100 controls. The glycaemic profile of 50 diabetics, taken the same day as the Ambulatory ECG recording, was subdivided into GGC (gluco-stick mean values between 100 and 140 mg/dL) or PGC (gluco-stick values ≤99 mg/dL in 3-of-4 daily determination or gluco-stick values ≥140 mg/dL in 3-of-4 daily determination).

RESULTS

Diabetics show a higher prevalence of either ventricular ectopic beats (VEBs) (93.47% vs. 82% controls, p < 0.05) and heart rate (both in sinus rhythm and in atrial fibrillation) (98.35 ± 10 beats/min in diabetics vs. 78.10 ± 8.1 in controls, p < 0.001). Moreover, diabetics with PGC show either a higher prevalence of VEBs (96.42% vs 77.27% in GGC, p < 0.05) and of supraventricular ectopic beats (SVEBs) (96.42% vs. 68.18 in GGC, p < 0.05); furthermore, diabetics with PGC show more severe and complex atrial and ventricular arrhythmias (SVEBs 32.14% vs 0%, p < 0.05; VEBs 39.28% vs 9.09%, p < 0.05).

CONCLUSIONS

The analysis of our sample shows that the arrhythmogenic condition is not only provided from diabetic condition per se but it is enhanced in PGC. Infact PGC patients showed higher number of VEBs, often polymorphic, expression of more severe arrhythmic and cardiovascular outcome. This could be partially explained by hyperactivation of autonomic nervous system during metabolic stress (which increases mean heart rate). Moreover more severe diabetic patients may present coronary microangiopathy that can further explain their arrhythmogenic tendency.

Diabetic peripheral neuropathy: should a chaperone accompany our therapeutic approach?

Diabetic peripheral neuropathy (DPN) is a common complication of diabetes that is associated with axonal atrophy, demyelination, blunted regenerative potential, and loss of peripheral nerve fibers. The development and progression of DPN is due in large part to hyperglycemia but is also affected by insulin deficiency and dyslipidemia. Although numerous biochemical mechanisms contribute to DPN, increased oxidative/nitrosative stress and mitochondrial dysfunction seem intimately associated with nerve dysfunction and diminished regenerative capacity. Despite advances in understanding the etiology of DPN, few approved therapies exist for the pharmacological management of painful or insensate DPN. Therefore, identifying novel therapeutic strategies remains paramount. Because DPN does not develop with either temporal or biochemical uniformity, its therapeutic management may benefit from a multifaceted approach that inhibits pathogenic mechanisms, manages inflammation, and increases cytoprotective responses. Finally, exercise has long been recognized as a part of the therapeutic management of diabetes, and exercise can delay and/or prevent the development of painful DPN. This review presents an overview of existing therapies that target both causal and symptomatic features of DPN and discusses the role of up-regulating cytoprotective pathways via modulating molecular chaperones. Overall, it may be unrealistic to expect that a single pharmacologic entity will suffice to ameliorate the multiple symptoms of human DPN. Thus, combinatorial therapies that target causal mechanisms and enhance endogenous reparative capacity may enhance nerve function and improve regeneration in DPN if they converge to decrease oxidative stress, improve mitochondrial bioenergetics, and increase response to trophic factors.

Morphological analysis of colon goblet cells and submucosa in type I diabetic rats submitted to physical training

Colon layers, especially the submucosa, as well as the secretion of goblet cells are extremely important for the functioning and transit of substances in this organ. However, the damages arising from type I diabetes and the effects of physical training, which plays crucial role in the treatment of this disease, are not yet known in these regions. To analyze the changes in colon submucosa and goblet cells of diabetic rats, as well as the effects of physical training, Wistar rats were divided into four groups: sedentary control, trained control, sedentary diabetic (SD), and trained diabetic (TD). The training protocol consisted of swimming for 60 min a day, 5 days per week, during 8 weeks. Colon samples were collected, processed, and evaluated by histochemical and ultrastructural techniques. Goblet and submucosa cells did not show alterations in shape, size, protein and carbohydrate content, in all treatment groups. Decreased amount of collagen fibers, however, was observed in the submucosa and lamina propria of SD rats, but this alteration was recovered in TDs. The ultrastructural analysis, in turn, revealed greater quantity of Golgi apparatus cisterns in SDs, distinctly than TDs, which showed improvement in this diabetic condition. Thus, physical training was responsible for the recovery of some important diabetic alterations, possibly improving the motility of substances in the large intestine. Nevertheless, it cannot be considered alone in the treatment of this disease, requiring the combined practice of other methods.

Dynamic aerobic exercise induces baroreflex improvement in diabetic rats

The objective of the present study was to investigate the effects of an acute aerobic exercise on arterial pressure (AP), heart rate (HR), and baroreflex sensitivity (BRS) in STZ-induced diabetic rats. Male Wistar rats were divided into control (n = 8) and diabetic (n = 8) groups. AP, HR, and BRS, which were measured by tachycardic and bradycardic (BR) responses to AP changes, were evaluated at rest (R) and postexercise session (PE) on a treadmill. At rest, STZ diabetes induced AP and HR reductions, associated with BR impairment. Attenuation in resting diabetes-induced AP (R: 103 ± 2 versus PE: 111 ± 3 mmHg) and HR (R: 290 ± 7 versus PE: 328 ± 10 bpm) reductions and BR dysfunction (R: −0.70 ± 0.06 versus PE: −1.21 ± 0.09 bpm/mmHg) was observed in the postexercise period. In conclusion, the hemodynamic and arterial baro-mediated control of circulation improvement in the postexercise period reinforces the role of exercise in the management of cardiovascular risk in diabetes.

Lifestyle interventions for cardiovascular risk reduction in women with breast cancer

PURPOSE

The purpose of this paper is to identify risk factors for cardiovascular disease in women with breast cancer and review healthy lifestyle behaviors as essential risk reduction strategies.

FINDINGS

Women with breast cancer account for 22% of the 12 million cancer survivors. Women diagnosed with breast cancer often present with modifiable and non-modifiable cardiovascular risk factors and/or pre-existing co-morbid illness. Any one or a combination of these factors may increase the risk of cardiovascular disease. There is strong evidence that healthy eating and routine physical activity can reduce cardiovascular disease. Exercise improves cardiovascular fitness, body composition and quality of life in breast cancer survivors and observational studies suggest a survival benefit.

CLINICAL IMPLICATIONS

Lifestyle interventions including a healthy diet, regular physical activity, weight management and smoking cessation should be integrated into a survivorship care plan to reduce cardiovascular disease risk and promote better health for women with breast cancer.

Factors influencing the outcomes of patients with both coronary artery disease and diabetes enrolled in standard cardiac rehabilitation programs: a literature review

Currently 23.5 million working-age adults 20 years or older have had a diagnosis of both coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM), with estimates that an additional 9% of the total US population will have a diagnosis of this chronic disease combination by the year 2025. Current annual health care costs for this working-age population including medical costs, functional disability, work loss, and premature mortality currently exceed $620 billion. Prior research efforts have shown that 25% to 32% of patients requiring a coronary revascularization procedure have both CAD and T2DM. The primary intervention prescribed for these patients to regain functional ability after revascularization is enrollment in a standard outpatient cardiac rehabilitation (CR) program. These standard programs, ranging in duration from 6 to 12 weeks, have been shown to improve the physical function of CAD patients by up to 15%, but patients diagnosed with both chronic conditions of CAD and T2DM (T2DM+CAD) attending these same programs exhibit only an 8% improvement. Moreover, T2DM+CAD patients experience much lower rates of rehabilitation program appointment adherence as well as greater program attrition (T2DM+CAD: 45%-62% vs CAD: 92%). Current medical literature regarding the relationship between CAD, T2DM, and cardiac rehabilitation will be examined to identify specific factors that could influence the functional outcomes achieved by the T2DM+CAD population when enrolled in a standard CR program and help increase understanding of why the adherence and attrition differences exist.

Evidence-based risk assessment and recommendations for physical activity clearance: diabetes mellitus and related comorbidities1This paper is one of a selection of papers published in this Special Issue, entitled Evidence-based risk assessment and recommendations for physical activity clearance, and has undergone the Journal’s usual peer review process

Physical activity (PA) is one of the most powerful treatment options for persons with prediabetes or diabetes. However, some elevation in risk occurs with increased PA, at least initially, and certain precautions need to be made to lower these risks, particularly if these persons are unaccustomed to exercise. We conducted a standardized search of all adverse events associated with increased PA in persons with prediabetes or diabetes (type 1 or type 2) and provided evidence-based guidelines on PA screening in these apparently high-risk individuals. A systematic literature review was performed of all studies reporting on adverse events in persons with prediabetes or diabetes. Studies included were from all designs (retrospective and prospective including randomized controlled trials) and were assessed according to evaluation criteria adapted by a consensus panel. A total of 47 studies, involving >8000 individuals, were deemed eligible. A number of these studies identified a range of mild to severe acute risks with exercise (musculoskeletal injury, hypoglycemia, foot ulceration, proliferative retinopathy, hypotension, sudden death) but the overall prevalence was low. Based on several randomized controlled trials and prospective studies in which prescribed exercise was performed at a wide range of intensities, it appears that increased PA is a relatively safe procedure with no evidence of a loss of life. Based on our assessment of the available literature, we provide a new PA risk algorithm for persons with prediabetes and diabetes and comment on the role of the patient, the qualified exercise professional, and the patient’s physician in the risk screening process.

A plantar flexion device exercise programme for patients with peripheral arterial disease: a randomised prospective feasibility study

OBJECTIVES

To determine if the use of a plantar flexion device (Step It pedal) in a newly developed exercise programme is of benefit to patients with peripheral arterial disease.

DESIGN

Prospective feasibility trial with patients randomised to either standard care or the Step It exercise programme plus standard care.

SETTING

Physiotherapy Department at Cumberland Infirmary, Carlisle, UK.

PARTICIPANTS

Patients were identified from the vascular team's referral list. In total, 42 patients agreed to take part; 18 in the control group and 24 in the intervention group.

INTERVENTIONS

Eligible participants were randomised and received either standard care or took part in a plantar flexion resistance exercise programme, involving the Step It pedal, for a period of 12 weeks.

MAIN OUTCOME MEASURES

Maximum walking distance, claudication distance and ankle brachial pressure index.

RESULTS

Eighty-three percent of patients completed the study. Improvements in median distance to claudication symptoms and maximum walking distance were observed in the intervention group but not in the control group. Nine out of 15 (60%) participants in the control group and 14 out of 20 (70%) participants in the intervention group improved their walking distance. Ankle brachial pressure index remained virtually unchanged in both groups.

CONCLUSIONS

Due to the variability of patients' fitness in the sample, it cannot be concluded whether use of the Step It pedal has additional benefits to patients over standard care. However, the study completion rate implies that patients with peripheral arterial disease are receptive to undertaking exercise programmes.

Electrocardiographic changes with the onset of diabetes and the impact of aerobic exercise training in the Zucker Diabetic Fatty (ZDF) rat

Background

Early markers of diabetic autonomic neuropathy (DAN) in an electrocardiogram (ECG) include elevated R wave amplitudes, widening of QT_c intervals and decreased heart rate variability (HRV). The severity of DAN has a direct relationship with mortality risk. Aerobic exercise training is a common recommendation for the delay and possible reversal of cardiac dysfunction. Limited research exists on ECG measures for the evaluation of aerobic exercise training in Zucker Diabetic Fatty (ZDF) rat, a model of type 2 diabetes. The objective of this study was to assess whether aerobic exercise training may attenuate diabetes induced ECG changes.

Methods

Male ZDF (obese fa/fa) and control Zucker (lean fa/+) rats were assigned to 4 groups: sedentary control (SC), sedentary diabetic (SD), exercised control (EC) and exercised diabetic (ED). The exercised groups began 7 weeks of treadmill training after the development of diabetes in the ED group. Baseline (prior to the training) and termination measurements included body weight, heart weight, blood glucose and glycated hemoglobin levels and ECG parameters. One way repeated measures ANOVA (group) analyzed within and between subject differences and interactions. Pearson coefficients and descriptive statistics described variable relationships and animal characteristics.

Results

Diabetes caused crucial changes in R wave amplitudes (p < 0.001), heart rate variability (p < 0.01), QT intervals (p < 0.001) and QT_c intervals (p < 0.001). R wave amplitude augmentation in SD rats from baseline to termination was ameliorated by exercise, resulting in R wave amplitude changes in ED animals similar to control rats. Aerobic exercise training neither attenuated QT or QT_c interval prolongation nor restored decreases in HRV in diabetic rats.

Conclusion

This study revealed alterations in R wave amplitudes, HRV, QT and QT_c intervals in ZDF rats. Of these changes, aerobic exercise training was able to correct R wave amplitude changes. In addition, exercise has beneficial effect in this diabetic rat model in regards to ECG correlates of left ventricular mass.

Common injuries in athletes with obesity and diabetes

Musculoskeletal injuries and diseases are common in persons with obesity and diabetes mellitus. High body mass index is associated with an increased risk for musculoskeletal injuries, diseases, and disability. There is a significant positive correlation between the level of obesity and musculoskeletal injuries, and disability and health-related costs. The prevalence of obesity and diabetes is inversely proportional to health-related quality of life.

Exercise and glycemic control in diabetes: benefits, challenges, and adjustments to pharmacotherapy

Exercise, along with dietary intervention, represents first-line therapy for diabetes mellitus. Aerobic exercise is recommended for its beneficial effects on glucose control as well as its abilities to retard the progression of other comorbidities common in patients with diabetes, such as cardiovascular disease. The capability of aerobic exercise to improve glycemic control in diabetes is well documented, although adherence to exercise regimens is problematic. More recently, the glucose-lowering effects of resistance training have also been documented; this form of exercise has additional benefits, such as the capability to counteract sarcopenia, which is common in older people with type 2 diabetes. Exercise in people with diabetes, however, also can present significant challenges to glycemic control. Excessive glucose lowering can occur under certain conditions, enhancing the threat of hypoglycemia; in other situations, hyperglycemia can be accentuated. An understanding of the interactions between specific antidiabetic medications and various forms and intensities of exercise is essential to optimizing glycemic control while minimizing the potential for acute derangements in plasma glucose levels. Exogenous forms of insulin and agents that stimulate insulin secretion in a glucose-independent manner (such as sulfonylureas and glinides) increase the propensity for hypoglycemia during low- to moderate-intensity aerobic exercise. In contrast, exercise protocols characterized by high intensity are more likely to result in episodes of hyperglycemia. Strategies to minimize inappropriate swings in glycemic control are reviewed.

Practical strategies to normalize hyperglycemia without undue hypoglycemia in type 2 diabetes mellitus

Hypoglycemia is a common problem in pharmacologically treated patients with type 2 diabetes mellitus and can be a major barrier to achieving optimal glycemic control. For practitioners to minimize and treat hypoglycemia, it is important to understand the physiology, risk factors, and medications associated with hypoglycemia. Through education, lifestyle modifications, medication adjustments, and possibly re-examining glycemic goals, practitioners can reduce the incidence of hypoglycemia while still decreasing the risk of microvascular complications associated with hyperglycemia.

Development of a neural network for prediction of glucose concentration in type 1 diabetes patients

BACKGROUND

A major difficulty in the management of diabetes is the optimization of insulin therapies to avoid occurrences of hypoglycemia and hyperglycemia. Many factors impact glucose fluctuations in diabetes patients, such as insulin dosage, nutritional intake, daily activities and lifestyle (e.g., sleep-wake cycles and exercise), and emotional states (e.g., stress). The overall effect of these factors has not been fully quantified to determine the impact on subsequent glycemic trends. Recent advances in diabetes technology such as continuous glucose monitoring (CGM) provides significant sources of data, such that quantification may be possible. Depending on the CGM technology utilized, the sampling frequency ranges from 1-5 min. In this study, an intensive electronic diary documenting the factors previously described was created. This diary was utilized by 18 patients with insulin-dependent diabetes mellitus in conjunction with CGM. Utilizing this dataset, various neural network models were constructed to predict glucose in these diabetes patients while varying the predictive window from 50-180 min. The predictive capability of each neural network within the fully trained dataset was analyzed as well as the predictive capabilities of the neural networks on unseen data.

METHODS

Neural network models were created using NeuroSolutions software with variable predictive windows of 50, 75, 100, 120, 150, and 180 min. Neural network models were trained using patient datasets ranging from 11-17 patients and evaluated on patient data not included in the neural network formulation. Performance analysis was completed for the neural network models using MATLAB. Performance measures include the calculation of the mean absolute difference percent overall and at hypoglycemic and hyperglycemic extremes, and the percentage of hypoglycemic and hyperglycemic occurrences were predicted.

RESULTS

Overall, the neural network models perform adequately at predicting at normal (>70 and <180 mg/dl) and hyperglycemic ranges (> or =180 mg/dl); however, glucose concentrations in areas of hypoglycemia were commonly overestimated. One potential reason for the "high" predictions in areas of hypoglycemia is due to the minimal occurrences of hypoglycemic events within the training data. The entire 18-patient dataset (consisting of 18,400 glucose values) had a relatively low incidence of hypoglycemia (1460 CGM values < or =70 mg/dl), which corresponds to approximately 7.9% of the dataset. On the contrary, hyperglycemia comprised approximately 35.7% of the dataset (6560 CGM values >or =180 mg/dl), and euglycemic values allotted for 56.4% of the dataset (10,380 CGM values >70 and <180 mg/dl). Results further indicate that an increase in predictive window leads to a decrease in predictive accuracy of the neural network model. It is hypothesized that the underestimation of hyperglycemic extremes is due to the extension of the predictive window and the associated inability of the neural network to determine oscillations and trends in glycemia as well as the occurrence of other relevant input events such as lifestyle, emotional states, insulin dosages, and meals, which may occur within the predicted time window and may impact or change neural network weights.

CONCLUSIONS

In this investigation, the feasibility of utilizing neural network models for the prediction of glucose using predictive windows ranging from 50-180 min is demonstrated. The predictive windows were chosen arbitrarily to cover a wide range; however, longer predictive windows were implemented to gain a predictive view of 120-180 min, which is very important for diabetes patients, specifically after meals and insulin dosages. Neural networks, such as those generated in this investigation, could be utilized in a semiclosed-loop device for guiding therapy in diabetes patients. Use of such a device may lead to better glycemic control and subsequent avoidance of complications.

The role of exercise training in peripheral arterial disease

Peripheral arterial disease (PAD) is currently a major health problem affecting 8-12 million Americans, 15-40% of whom will have intermittent claudication that can lead to substantial impairment in their ability to carry out normal daily activities as well as perform the recommended cardiovascular exercise. Supervised exercise training is an effective tool in the treatment of claudication and is currently a recommended first-line therapy for patients with this condition. In addition to improving pain-free walking distance and quality of life, supervised exercise training can improve many cardiovascular risk factors, possibly reducing the risk for subsequent myocardial infarction, stroke, and death. This paper will review the benefits of supervised exercise training in patients with PAD.

Pioglitazone improves metabolic markers in patients with type 2 diabetes independently from physical activities: results from the IRIS III study

AIM

Pioglitazone is an established peroxisome proliferator-activated receptor gamma agonist for the treatment of insulin resistance in patients with type 2 diabetes mellitus. This analysis of the observational IRIS III study was performed to evaluate the effects of pioglitazone treatment in relation to the degree of physical exercise activities in a large patient population under daily life conditions.

METHODS

A total of 1298 patients out of 2092 enrolled into the IRIS III study who had provided information about their exercise level could be included in the final analysis (622 female, 676 male; age: 63.1 +/- 10.4 years, diabetes duration: 6.6 +/- 5.0 years, mean +/- SD). All patients were glitazone naïve prior to study entry. They received pioglitazone in addition to their previous oral antidiabetic treatment. The patients were stratified according to their physical activity level (never, sometimes, and regularly). Data were evaluated at baseline and after 20 +/- 2 weeks of treatment. Observation parameters were fasting blood glucose, lipids, and blood pressure. Hemoglobin A1c (HbA1c) was determined in a central laboratory, and insulin sensitivity was assessed by the IRIS II score.

RESULTS

Glycemic control, blood pressure, and the lipid profile improved independently from the degree of physical activity (e.g., no exercise vs frequent exercise: DeltaHbA1c: -0.89 +/- 1.2% vs -0.72 +/- 1.1%, not significant). A positive impact of exercise on insulin resistance could be observed at baseline, which, however, was further decreased by pioglitazone treatment [IRIS II score (baseline/end point): no exercise vs frequent exercise: 74.0 +/- 15.9/62.5 +/- 20.2 vs 66.7 +/- 19.0/58.0 +/- 21.8, p < 0.001/not significant].

CONCLUSIONS

These observational results, obtained from a nonselected patient population under daily routine conditions, confirm that the benefits of pioglitazone treatment on glycemic control, lipid metabolism, and blood pressure are independent from physical activity. Exercise has a positive influence on insulin sensitivity, but pioglitazone shows additional favorable effects and is, therefore, recommended for use independently from the activity level of the patients.

Interventions for being active among individuals with diabetes: a systematic review of the literature

PURPOSE

The purpose of this systematic review is to assess and summarize evidence and gaps in the literature regarding the intervention for being active (exercise) among individuals with diabetes.

METHODS

Twelve electronic databases were searched. Publications eligible for inclusion specifically studied learning, behavioral, clinical, and humanistic outcomes for exercise interventions in adult patients with type 1 and type 2 diabetes.

RESULTS

Seven reviews (2 systematic reviews, 3 meta-analyses, 2 technical reviews) and 34 individual, nonreview studies (18 randomized controlled trials, 16 nonrandomized trials) met inclusion criteria. For type 2 diabetes, findings suggested that exercise had a positive effect on glycemic control and decreased cardiovascular risk, but the impact of exercise on behavioral and humanistic outcomes was unclear; long-term outcomes and adherence to exercise interventions is unknown because most studies were of short duration. The overall impact of varied types of exercise in type 1 diabetes was unclear, especially regarding glycemic control. Potential benefits of exercise in type 1 may include improved cardiovascular health.

CONCLUSION

The review did not identify specific successful intervention details because of the heterogeneity of studies, subjects, and research gaps. General findings suggest that physical activity is better than no exercise at all; intensive regimens, if tolerated by patients, achieved better clinical outcomes than less intensive regimens. Reviewed studies using structured exercise regimens exhibited a more significant impact on outcomes. Substantial gaps in the literature include studies measuring direct effects of exercise in the US minority populations most affected by type 2 diabetes and economic evaluations of exercise interventions. Interventions must be tailored to individual patient needs to succeed.

Educational disparities in health behaviors among patients with diabetes: the Translating Research Into Action for Diabetes (TRIAD) Study

Background

Our understanding of social disparities in diabetes-related health behaviors is incomplete. The purpose of this study was to determine if having less education is associated with poorer diabetes-related health behaviors.

Methods

This observational study was based on a cohort of 8,763 survey respondents drawn from ~180,000 patients with diabetes receiving care from 68 provider groups in ten managed care health plans across the United States. Self-reported survey data included individual educational attainment ("education") and five diabetes self-care behaviors among individuals for whom the behavior would clearly be indicated: foot exams (among those with symptoms of peripheral neuropathy or a history of foot ulcers); self-monitoring of blood glucose (SMBG; among insulin users only); smoking; exercise; and certain diabetes-related health seeking behaviors (use of diabetes health education, website, or support group in last 12 months). Predicted probabilities were modeled at each level of self-reported educational attainment using hierarchical logistic regression models with random effects for clustering within health plans.

Results

Patients with less education had significantly lower predicted probabilities of being a non-smoker and engaging in regular exercise and health-seeking behaviors, while SMBG and foot self-examination did not vary by education. Extensive adjustment for patient factors revealed no discernable confounding effect on the estimates or their significance, and most education-behavior relationships were similar across sex, race and other patient characteristics. The relationship between education and smoking varied significantly across age, with a strong inverse relationship in those aged 25–44, modest for those ages 45–64, but non-evident for those over 65. Intensity of disease management by the health plan and provider communication did not alter the examined education-behavior relationships. Other measures of socioeconomic position yielded similar findings.

Conclusion

The relationship between educational attainment and health behaviors was modest in strength for most behaviors. Over the life course, the cumulative effect of reduced practice of multiple self-care behaviors among less educated patients may play an important part in shaping the social health gradient.

Combination therapy with new targets in Type 2 diabetes: a review of available agents with a focus on pre-exercise adjustment

The current strategy for treating type 2 diabetes mellitus promotes combination therapy to address the 3 major defects in type 2 diabetes mellitus: (1) impaired peripheral glucose uptake (liver, fat, and muscle), (2) excessive hepatic glucose release (with glucagon excess), and (3) insufficient insulin secretion. Providers can prescribe medications that may have advantageous secondary effects in a patient-specific manner. Adjustment for exercise is generally necessary only with insulin and with medications that may allow insulin secretion despite decreasing glucose levels, such as sulfonylurea drugs. Recently, newer oral medications that address beta-cell dysfunction have been designed to avoid hypoglycemia and to "match" nutritional and non-nutritional needs more directly. Incorporating these agents into regimens will likely reduce hypoglycemia and therefore increase the safety and efficacy of exercise as both a treatment and cardiac monitoring strategy for patients with diabetes.

Dietary advice for treatment of type 2 diabetes mellitus in adults

BACKGROUND

While initial dietary management immediately after formal diagnosis is an 'accepted' cornerstone of treatment of type 2 diabetes mellitus, a formal and systematic overview of its efficacy and method of delivery is not currently available.

OBJECTIVES

To assess the effects of type and frequency of different types of dietary advice for adults with type 2 diabetes.

SEARCH STRATEGY

We carried out a comprehensive search of The Cochrane Library, MEDLINE, EMBASE, CINAHL, AMED, bibliographies and contacted relevant experts.

SELECTION CRITERIA

All randomised controlled trials, of six months or longer, in which dietary advice was the main intervention.

DATA COLLECTION AND ANALYSIS

The lead investigator performed all data extraction and quality scoring with duplication being carried out by one of the other six investigators independently with discrepancies resolved by discussion and consensus. Authors were contacted for missing data.

MAIN RESULTS

Thirty-six articles reporting a total of eighteen trials following 1467 participants were included. Dietary approaches assessed in this review were low-fat/high-carbohydrate diets, high-fat/low-carbohydrate diets, low-calorie (1000 kcal per day) and very-low-calorie (500 kcal per day) diets and modified fat diets. Two trials compared the American Diabetes Association exchange diet with a standard reduced fat diet and five studies assessed low-fat diets versus moderate fat or low-carbohydrate diets. Two studies assessed the effect of a very-low-calorie diet versus a low-calorie diet. Six studies compared dietary advice with dietary advice plus exercise and three other studies assessed dietary advice versus dietary advice plus behavioural approaches. The studies all measured weight and measures of glycaemic control although not all studies reported these in the articles published. Other outcomes which were measured in these studies included mortality, blood pressure, serum cholesterol (including LDL and HDL cholesterol), serum triglycerides, maximal exercise capacity and compliance. The results suggest that adoption of regular exercise is a good way to promote better glycaemic control in type 2 diabetic patients, however all of these studies were at high risk of bias.

AUTHORS' CONCLUSIONS

There are no high quality data on the efficacy of the dietary treatment of type 2 diabetes, however the data available indicate that the adoption of exercise appears to improve glycated haemoglobin at six and twelve months in people with type 2 diabetes. There is an urgent need for well-designed studies which examine a range of interventions, at various points during follow-up, although there is a promising study currently underway.

Prevalence of Type 2 Diabetes and Physical Activity Status in Elderly Men and Women from Cyprus (the MEDIS STUDY)

Our aim is to investigate the association of being physically active on the prevalence of Type 2 diabetes mellitus among elderly people. We enrolled 53 men and 97 women, aged 65 to 100, from various areas of Cyprus. Physical activity was evaluated through a validated questionnaire (the short International Physical Activity Questionnaire, IPAQ). Prevalence of diabetes was 26% in men and 18% in women, while 55% of men and 50% of women were reported as being moderately or vigorously active. Furthermore, 5% of the participants reported that they smoked, 4% had stopped smoking, and 8% reported alcohol consumption. People in the upper tertile of the IPAQ score were 0.26 times less likely to have diabetes (p < 0.05); on the other hand people in the lower tertile of the score were 1.7 times more likely to have diabetes (p < 0.05). Our findings support the notion of a beneficial effect of physical activity on the burden of diabetes in the elderly. Asia Pac J Public Health 2007; 19(3): 22-28.

Exercise training improves arterial baro- and chemoreflex in control and diabetic rats

We investigated the effect of exercise training on blood pressure, heart rate, and arterial baro- and chemoreflex sensitivity in diabetic rats (streptozotocin, 50 mg/kg iv). Male Wistar rats (251+/-10 g) were divided into 4 groups (n=8, each group): sedentary normotensive (SC), sedentary diabetic (SD), trained normotensive (TC), and trained diabetic (TD). Trained groups underwent exercise training on a treadmill (10 weeks). Exercise training induced resting bradycardia (340+/-5 vs. 316+/-8 bpm) and improvement in baroreflex tachycardic response (3.4+/-0.31 vs. 2.7+/-0.06 bpm/mmHg in SC) and chemoreflex bradycardic (145+/-12 vs. 78+/-7 bpm in SC) and pressor (49+/-5 vs. 22+/-3 mmHg in SC) responses in control rats. Diabetic-induced hypotension (SC: 107+/-2 vs. SD: 93+/-2 mmHg) and bradycardia (SC: 340+/-5 vs. SD: 276+/-7 bpm) were reversed by exercise training. Baroreflex tachycardic and bradycardic responses impaired in SD rats (SD: 2.1+/-0.18 and 1.3+/-0.08 vs. SC: 2.7+/-0.06 and 1.3+/-0.08 bpm/mmHg) were enhanced in TD rats (2.5+/-0.1 and 1.7+/-0.06 bpm/mmHg). Chemoreflex bradycardic and pressor responses, attenuated in SD rats (23+/-9 bpm and 7+/-1 mmHg) in relation to SC rats, were improved by exercise (TD: 84+/-15 bpm and 32+/-5 mmHg). The improvement in arterial baro- and chemoreflex-mediated control of circulation in trained control and diabetic rats reinforces the role of exercise in the management of cardiovascular risk in healthy and diabetic individuals.

Exercise frequency and arterial compliance in non-diabetic and type 1 diabetic individuals

BACKGROUND

The role of exercise in preventing cardiovascular disease (CVD) has been well documented. To determine whether this benefit could be related to effects on vascular endothelial function and vessel wall elasticity, thereby preserving arterial compliance, we examined the relationship between habitual exercise and arterial compliance as measured by pulse wave analysis.

DESIGN

A cross-sectional study of healthy volunteers and patients with type 1 diabetes.

METHODS

Non-diabetic individuals not taking cholesterol or blood pressure-lowering medication (n=176) and patients with type 1 diabetes (n=105), aged 17-70 years, were recruited. Small and large artery compliance and other haemodynamic variables were measured using the PulseWave CR-2000 cardiovascular profiling system. A questionnaire was completed to assess the frequency of physical activity.

RESULTS

In multivariate analysis, undertaking three or more episodes of vigorous activity per week was associated with having a 1 unit greater small artery compliance, independent of age, sex, height, diabetes status and blood pressure. The effect was especially marked in non-diabetic women.

CONCLUSIONS

The results support other findings that regular physical activity protects against CVD, through the preservation of vascular compliance.