Cardiorespiratory fitness and physical activity in youth with type 2 diabetes

Household Food Insecurity Is Associated With Physical Activity in Youth and Young Adults With Diabetes: A Cross-Sectional Study

BACKGROUND

Physical activity (PA) is essential for optimal diabetes management. Household food insecurity (HFI) may negatively affect diabetes management behaviors. The purpose of this study was to cross-sectionally examine the association between HFI and PA in youth and young adults (YYA) with type 1 (N = 1998) and type 2 (N = 391) diabetes from the SEARCH for Diabetes in Youth Study.

METHODS

HFI was measured with the US Household Food Security Survey Module. PA was measured with the International Physical Activity Questionnaire Short Form. Walking, moderate-intensity PA (excluding walking), vigorous-intensity PA, moderate- to vigorous-intensity PA, and total PA were estimated as minutes per week, while time spent sitting was assessed in minutes per day. All were modeled with median regression. Meeting PA guidelines or not was modeled using logistic regression.

RESULTS

YYA with type 1 diabetes who experienced HFI spent more time walking than those who were food secure. YYA with type 2 diabetes who experienced HFI spent more time sitting than those who were food secure.

CONCLUSIONS

Future research should examine walking for leisure versus other domains of walking in relation to HFI and use objective PA measures to corroborate associations between HFI and PA in YYA with diabetes.

Cardiovascular disease risk profile of Indian young adults with type 1 diabetes compared to general population - A sub-study from the Young Diabetes Registry (YDR), India

OBJECTIVE

We estimated the prevalence of traditional CVD risk factors among young adults with type 1 diabetes and compared them with the general population without diabetes.

METHODS

Participants were young adults (aged 20 years and above) with type 1 diabetes, from the Delhi and Chennai sites of the ICMR -Young Diabetes Registry (YDR) and their age, gender and location matched controls, without diabetes from the CARRS (Cardio metabolic Risk Reduction in South Asia) cohort. YDR and CARRS used similar standard methodologies to quantify the CVD risk factors. Linear and logistic regression models were used to compare the adjusted means and proportions of risk factors.

RESULTS

Individuals with type 1 diabetes had lower levels of mean BMI (21.9 kg/m2 vs 24.3 kg/m2), waist circumference (76.8 cm vs 82.1 cm), favourable lipid profile (lower LDL and higher HDL), higher mean systolic blood pressure (122.1 mmHg vs 118.7 mmHg) and hypertension (29.2% vs 21.0%), compared to controls. The extent of clustering of two or more traditional CVD risk factors was higher among general population compared to people with type 1 diabetes.

CONCLUSION

We found that young adults with type 1 diabetes have relatively low prevalence and clustering of traditional CVD risk factors compared to general population.

Examining How Neighborhood Socioeconomic Status, Geographic Accessibility, and Informational Accessibility Influence the Uptake of a Free Population-Level Physical Activity Intervention for Children

PURPOSE

To evaluate the uptake of ACT-i-Pass (G5AP), a physical activity (PA) intervention that provides free access to PA opportunities, and to understand the extent to which the intervention provides equitable access to children.

DESIGN

This study evaluates the differences in uptake (ie, enrollment) by comparing postal codes of registrants with the postal codes of all eligible children.

SETTING

Children were provided the opportunity to register for the G5AP during the 2014 to 2015 school year in London, Canada.

PARTICIPANTS

The population of grade 5 students in London who registered for the G5AP (n = 1484) and did not register (n = 1589).

INTERVENTION

The G5AP offered grade 5 students free access to select PA facilities/programs during 2014 to 2015 school year.

MEASURES

Measures included G5AP registration status, method of recruitment, distance between home and the nearest facility, and neighborhood socioeconomic status.

ANALYSIS

Getis-Ord Gi* and multilevel logistic regression were used to analyze these data.

RESULTS

There were significant differences in the uptake of the G5AP: residing in neighborhoods of high income (odds ratio [OR] = 1.062, P = .029) and high proportion of recent immigrants (OR = 1.036, P = .001) increased the likelihood of G5AP registration. Children who were recruited actively were significantly more likely to register for the G5AP (OR = 2.444, P < .001).

CONCLUSION

To increase the uptake of a PA intervention, children need to be actively recruited. Interactive presentations provide children with increased access to information about both the program and its nuances that cannot be communicated as effectively through passive methods.

The ACT-i-Pass study protocol: How does free access to recreation opportunities impact children's physical activity levels?

BACKGROUND

Physical activity during childhood is associated with a multitude of physical, behavioural, and psychological health benefits. Identification of effective population level strategies for increasing children's physical activity levels is critical for improving the overall health of Canadians. The overall objective of this study is to assess how a naturally-occurring, community-level intervention which offers Grade 5 children in London, Canada a free access pass to physical activity opportunities (facilities and programs) for an entire school year can lead to increased physical activity among recipients.

METHODS/DESIGN

This study adopts a longitudinal cohort study design to assess the effectiveness of improving children's access to physical activity opportunities for increasing their physical activity levels. To meet our overall objective we have three aims: (1) to assess whether the provision of free access increases children's physical activity levels during and after the intervention compared to a control group; (2) to assess how and why child-specific trajectories of physical activity (between-children differences in level of physical activity measured across time) in the intervention group differ according to children's individual and household characteristics; and (3) to explore additional factors that are unaccounted for in the theoretical model to gain a further understanding of why the free access intervention had varying effects on changing physical activity levels. We will be addressing these aims using a mixed methods approach, including: a series of youth surveys conducted before, during, immediately after, and 4-months after the intervention; parent surveys before, during, and post-intervention; real-time tracking of the access pass use during the intervention; and focus groups at the conclusion of the intervention. Data compiled from the youth surveys will provide a subjective measure of physical activity to be used as our outcome measure to address our primary aims.

DISCUSSION

The results of this study can inform policy- and decision-makers about the sub-groups of the population that benefitted the most (or least) from the intervention to provide more specific information on how to develop and target future interventions to have a greater impact on the physical activity levels and overall health of children.

Proposed trial: safety and efficacy of resveratrol for the treatment of non-alcoholic fatty liver disease (NAFLD) and associated insulin resistance in adolescents who are overweight or obese adolescents - rationale and protocol

Non-alcoholic fatty liver (NAFL) disease (NAFLD) affects 30% of overweight adolescents and increases the risk of type 2 diabetes mellitus (T2D). Resveratrol is a naturally occurring compound with potential to reverse NAFL and its associated insulin resistance in adults. The use of resveratrol to reduce risk for T2D through its effect on NAFL has not been examined to date in youth. This paper provides a literature review and protocol for a 30 day proof of principle trial of resveratrol in a population of adolescents at risk for T2D. This randomized double-blind controlled trial is designed with the primary objective of evaluating a twice daily supplementation of 75 mg of resveratrol for safety and tolerability in overweight and obese adolescent subjects (13 to <18 years of age) with NAFL. Secondary objectives are to determine the effect size of the intervention on hepatic steatosis and whole body insulin sensitivity. Adolescents in the intervention arm (n = 10) will receive oral supplementation of resveratrol 75 mg twice daily (with breakfast and dinner) for a total daily dose of 150 mg for the duration of 30 days. The comparison group (n = 10) will receive a placebo twice daily for 30 days. Both cases and controls will receive a standardized lifestyle intervention program. Subjects in both groups will be followed for an additional 30 days post intervention for total study duration of approximately 60 days. Primary outcome measures include a primary side effect profile determined by participant interview, a side effect profile determined by serum biochemistry and vital signs. Secondary outcome measures include an oral glucose tolerance test, liver and cardiac fat content measured by magnetic resonance spectroscopy, anthropometric measures of overweight/obesity, inflammatory markers, and cardiac function and morphology measured with ultrasonography. Additional outcome measures include serum concentrations of resveratrol, compliance to protocol, physical activity, and nutritional assessment. This study will determine the safety and tolerability of resveratrol in an overweight adolescent population and inform the design of a larger randomized controlled trial.

Lifestyle therapy for the treatment of youth with type 2 diabetes

Type 2 diabetes (T2D) in youth is a relatively novel condition facing paediatric health care providers. Few experimental trials exist to guide clinical management in this population. Supporting and prescribing modifiable lifestyle behaviours is cornerstone in the management of T2D in adults. Clinical trials in obese adolescents suggest that intensive lifestyle interventions that include both dietary changes and increased physical activity elicit clinically meaningful reductions in weight and improve cardiovascular risk profiles. Observational studies in youth with T2D suggest that better diet quality and increased physical activity are associated with better metabolic control; however, the limited experimental data available does not support these observations. Trials evaluating lifestyle monotherapy for the treatment of hyperglycaemia in youth with T2D do not exist, and the only study evaluating combined lifestyle and pharmacologic therapy did not show additional benefit over pharmacologic treatment with metformin alone. Physiological and psychosocial differences between youth and adults with T2D likely contribute to the differences in the effectiveness of lifestyle therapy for improving glycaemic control. The current review describes these topics in detail and provides recommendations for paediatric health care providers for the promotion of lifestyle therapy for the management of hyperglycaemia and cardiovascular risk factors for youth with T2DM.

Obesity and type 2 diabetes in children: epidemiology and treatment

The incidence of overweight and obesity among children has increased dramatically in recent decades, with about one-third of children in the U.S. currently being either overweight or obese. Being overweight in early childhood increases risk for later obesity. There is evidence for the efficacy of family-based behavioral treatment to control weight and improve health outcomes. Obesity-related health risks have been documented, including metabolic syndrome. There is also increasing incidence of type 2 diabetes (T2D) among youth in recent years, with obesity and family history of T2D generally present. Lower income and ethnic minority status are associated with both obesity and T2D in youth. Most youth with T2D do not achieve optimal glycemic control, and are at high risk for later health complications. Obesity and T2D represent significant public health issues with potentially great personal and societal cost. Research addressing the prevention of obesity and T2D among youth is urgently needed.

Physical activity and self-concept: the SEARCH for diabetes in youth case control study

In this study, the relationship between physical activity (PA) and 3 self-concept constructs (physical abilities, physical appearance, and general self-concept) was examined. Youth with type 1 diabetes (n = 304), type 2 diabetes (n = 49), and nondiabetic controls (n = 127) aged 10-20 years wore pedometers over 7 days. Youth completed the Self-Description Questionnaire and correlation coefficients were calculated. Mean steps/day were 7413 ± 3415, 4959 ± 3474 and 6870 ± 3521 for type 1, type 2 and control youth, respectively. Significant correlations were found between steps/day and perception of physical abilities (r = .29; r = .31; r = .31) for type 1, type 2, and control youth, respectively. The other correlations were not significant. Among youth with type 2 diabetes, steps/day were significantly correlated with physical appearance (r = .46). The positive correlation between PA and physical abilities suggests a reciprocal relationship between behavior and perception.

Physical exercise and pancreatic islets: acute and chronic actions on insulin secretion

Diabetes mellitus (DM) is a great public health problem, which attacks part of the world population, being characterized by an imbalance in body glucose homeostasis. Physical exercise is pointed as a protective agent and is also recommended to people with DM. As pancreatic islets present an important role in glucose homeostasis, we aim to study the role of physical exercise (chronic adaptations and acute responses) in pancreatic islets functionality in Wistar male rats. First, animals were divided into two groups: sedentary (S) and aerobic trained (T). At the end of 8 weeks, half of them (S and T) were submitted to an acute exercise session (exercise until exhaustion), being subdivided as acute sedentary (AS) and acute trained (AT). After the experimental period, periepididymal, retroperitoneal and subcutaneous fat pads, blood, soleus muscle and pancreatic islets were collected and prepared for further analysis. From the pancreatic islets, total insulin content, insulin secretion stimulated by glucose, leucine, arginine and carbachol were analyzed. Our results pointed that body adiposity and glucose homeostasis improved with chronic physical exercise. In addition, total insulin content was reduced in group AT, insulin secretion stimulated by glucose was reduced in trained groups (T and AT) and insulin secretion stimulated by carbachol was increased in group AT. There were no significant differences in insulin secretion stimulated by arginine and leucine. We identified a possible modulating action on insulin secretion, probably related to the association of chronic adaptation with an acute response on cholinergic activity in pancreatic islets.

Hepatic steatosis and low cardiorespiratory fitness in youth with type 2 diabetes

The purpose of this study was to examine the association between cardiorespiratory fitness, ectopic triglyceride accumulation, and insulin sensitivity among youth with and without type 2 diabetes. Subjects included 137 youth ages 13-18 years including 27 with type 2 diabetes, 97 overweight normoglycemic controls, and 13 healthy weight normoglycemic controls. The primary outcome measure was cardiorespiratory fitness defined as peak oxygen uptake indexed to fat free mass. Secondary outcomes included liver and muscle triglyceride content determined by (1)H-magnetic resonance spectroscopy and insulin sensitivity determined by frequently sampled intravenous glucose tolerance test. Despite similar measures of adiposity, peak oxygen uptake was 11% lower (38.9 ± 7.9 vs. 43.9 ± 6.1 ml/kgFFM/min, P = 0.002) and hepatic triglyceride content was nearly threefold higher (14.4 vs. 5.7%, P = 0.001) in youth with type 2 diabetes relative to overweight controls. In all 137 youth, cardiorespiratory fitness was negatively associated with hepatic triglyceride content (r = -0.22, P = 0.02) and positively associated with insulin sensitivity (r = 0.29, P = 0.002) independent of total body and visceral fat mass. Hepatic triglyceride content was also negatively associated with insulin sensitivity (r = -0.35, P < 0.001), independent of adiposity, sex, age, and peak oxygen uptake. This study demonstrated that low cardiorespiratory fitness and elevated hepatic triglyceride content are features of type 2 diabetes in youth. Furthermore, cardiorespiratory fitness and hepatic triglyceride are associated with insulin sensitivity in youth. Taken together, these data suggest that cardiorespiratory fitness and hepatic steatosis are potential clinical biomarkers for type 2 diabetes among youth.

Developmental origins of type 2 diabetes in aboriginal youth in Canada: it is more than diet and exercise

Type 2 diabetes mellitus (T2DM) is classically viewed as a disease of adults caused by poor nutrition, physical inactivity, and obesity. However, with increasing awareness of the heterogeneity of T2DM, new risk factors are being identified that add complexity. Some of these new risk factors have been identified in Canadian people with Aboriginal Oji-Cree heritage, a group that demonstrates one of the highest rates of T2DM in the world. This high prevalence may be due to the rapid change, over the past 50 years, away from their traditional way of life on the land. Another environmental change is the increased rate of pregnancies complicated by obesity, gestational diabetes, or T2DM, resulting in more children being exposed to an abnormal intrauterine environment. Furthermore, the Oji-Cree of central Canada possesses the unique HNF-1α G319S polymorphism associated with reduced insulin secretion. We propose that intrauterine exposure to maternal obesity and T2DM, associated with the HNF-1α G319S polymorphism, results in fetal programming that accelerates the progression of early-onset T2DM. This paper describes the evolution of T2DM in children with a focus on the Oji-Cree people over the past 25 years and the unique prenatal and postnatal gene-environment interaction causing early-onset T2DM.

Muscular strength and markers of insulin resistance in European adolescents: the HELENA Study

The aim of the study was to examine the association of muscular strength with markers of insulin resistance in European adolescents. The study comprised a total of 1,053 adolescents (499 males; 12.5-17.5 years) from ten European cities participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Cross-Sectional Study. Muscular strength was measured by the handgrip strength and standing long jump tests. Cardiorespiratory fitness was measured by the 20-m shuttle run test. Fasting insulin and glucose were measured and the homeostasis model assessment (HOMA) and quantitative insulin sensitivity check index (QUICKI) indices were calculated. Weight, height, waist circumference and skinfold thickness were measured, and body mass index (BMI) was calculated. In males, the handgrip strength and standing long jump tests were negatively associated with fasting insulin and HOMA (all P < 0.05) after controlling for pubertal status, country and BMI or waist circumference. When skinfold thickness was included in the model, the association became non-significant. In females, the standing long jump test was negatively associated with fasting insulin and HOMA (all P < 0.001) after controlling for pubertal status, country and surrogate markers of total or central body fat (BMI, waist circumference or skinfold thickness). Findings were retained in males, but not in females after controlling for cardiorespiratory fitness. The findings of the present study suggest that preventive strategies should focus not only on decreasing fatness and increasing cardiorespiratory fitness but also on enhancing muscular strength.

Using nature and outdoor activity to improve children's health

Childhood obesity affects 17% or 12.5 million of America's children, contributing to the rise in children's health disparities. Type 2 diabetes, asthma, vitamin D deficiency, and attention-deficit/hyperactivity disorder have also increased over the past few decades. A shift toward a sedentary lifestyle is a major contributor to the decline in children's health. Children spend more time indoors using electronic media and less time engaged in outdoor unstructured play. This article reviews the current evidence of the mental and physical health benefits associated with unstructured, outdoor activities and time spent in a natural environment such as a park or other recreational area. Pediatric health care providers should recommend outdoor activities for children and refer families to safe and easily accessible outdoor areas. Pediatric health care providers can incorporate this simple, lifestyle-based intervention into anticipatory guidance.

Type 2 diabetes in youth: a phenotype of poor cardiorespiratory fitness and low physical activity

OBJECTIVE

The increased incidence of obesity and type 2 diabetes (T2D) among youth has prompted the development of guidelines for healthy cardiorespiratory fitness (CRF) and physical activity (PA) levels in the pediatric population. It is unclear whether youth with T2D meet these guidelines as previous research has not included type 2 diabetics. Therefore, the purpose of this investigation was to examine CRF and PA in youth with T2D and compare these results with recently published normative data for CRF and guidelines for PA in youth. METHODS. Forty adolescents (17 males and 23 females) with T2D were assessed for moderate-to-vigorous PA via the 7-day PA recall. CRF was determined by a progressive cycle ergometer test and indirect calorimetry. PA levels were compared with recently published guidelines for youth of 60 minutes per day, and CRF data were compared with age- and sex-adjusted normative values from the National Health and Nutrition Examination Survey 1999-2002. Results. Only 17.6% (3/17) of boys and 21.7% (5/23) of girls met PA guidelines, while none of the participants met criteria for healthy CRF. When compared with normative CRF data for US youth, approximately 93% of boys and 95% of girls scored below the 10th percentile.

CONCLUSIONS

These results suggest that youth with T2D exhibit low levels of CRF and the majority do not participate in recommended amounts of PA. Practitioners working with type 2 diabetic youth need to emphasize the importance of regular PA to increase CRF and promote cardiovascular health in an effort to decrease long-term diabetes-related complications.

Update on nonautoimmune diabetes in children

Over the last two decades, nonautoimmune-mediated type 2 diabetes mellitus (T2DM) has become a clinical entity of increasing importance among adolescents. Yet, research specific to adolescent T2DM is in its infancy. Our understanding of the epidemiology of T2DM among adolescents is complicated by variability in definition, incomplete knowledge of novel autoimmune epitopes, the presence of individuals with phenotypic overlap between type 1 and type 2 diabetes, and inadequate understanding of the contribution of common single-gene defects. Furthermore, a higher ratio of diagnosed to undiagnosed cases and a strong relationship with the onset of puberty suggest unique aspects of the pathophysiology in adolescents. Investigators have begun to address these areas while also identifying important relationships with the intrauterine development. Well-designed clinical studies are currently examining the adolescent-specific challenges in prevention and treatment of T2DM, whereas a number of associations struggle to provide screening and treatment guidelines to practitioners based on limited understanding of the phenomenon. Finally, there is growing understanding of medium- and long-term morbidity and mortality in early adulthood. Given the likelihood that early-onset T2DM will have important implications for future public health, continued attention to all aspects of this complex social, economic, and physiological disorder is critical.