Etiology of insulin resistance in youth with type 2 diabetes

The characteristics and risk of obesity central and concomitant impaired fasting glucose: Findings from a cross-sectional study

INTRODUCTION

Obesity is associated with concomitant chronic conditions. An early metabolic consequence of obesity is disruption of glucose and insulin homeostasis. One of the consequences is impaired fasting glucose (IFG). Visceral fat is metabolically more harmful than subcutaneous fat, but few information is available regarding the association between the risk of abnormal glucose in increased waist circumference.

METHODS

This study is based on a cross sectional of 1,381 population-based from Palembang, Indonesia. The eligibility requirements subject were to be older than 18 and consent to taking fasting glucose and lipid profile tests as well as physical exams measuring their body weight, height, blood pressure, abdominal circumference, and waist circumference.

RESULTS

The number of subjects consisting of 798 noncentral obesity with normoglycemia, 376 central obesity with normoglycemia, and 207 central obesity with concomitant IFG. The prevalence central obesity with concomitant IFG was 35.51%. In subjects with central obesity, there were significant differences in proportions based on sex, age, marital status, education, and occupation. In multivariate analysis show that the risk factors that contribute to having a significant association with central obesity with concomitant IFG are sex (female), age (>40 years), blood pressure (hypertension), and HDL-C <50 mg/dL (p<0.001). The analysis also founded that there was a significant difference in the dietary pattern of sweet foods (p = 0.018), sweet drinks (p = 0.002), soft drinks (p = 0.001) and smoking habit (p<0.001) between subjects with obesity central and concomitant IFG compared to subjects with noncentral obesity. The majority of subjects with obesity central and concomitant IFG had consuming these risky foods >6 times/week.

CONCLUSION

The prevalence of central obesity with IFG is quite high. There are significant differences in the characteristics, lipid profile, blood pressure, dietary pattern, and smoking habit of central obesity with concomitant IFG was confirmed in this population-based observational study.

Incidence of Type 2 Diabetes in Children With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Type 2 diabetes (T2D) is a growing problem in children. Children with NAFLD are at potentially high risk for developing T2D; however, the incidence of T2D in this population is unknown. This study aimed to determine the incidence of T2D in children with NAFLD and identify associated risk factors.

METHODS

Children with NAFLD enrolled in the Nonalcoholic Steatohepatitis Clinical Research Network were followed longitudinally. Incidence of T2D was determined by using clinical history and fasting laboratory values. Cumulative incidence curves were developed for time to T2D. A Cox regression multivariable model was constructed using best subsets Akaike's Information Criteria selection.

RESULTS

This study included 892 children with NAFLD and with a mean age of 12.8 years (2.7) followed for 3.8 years (2.3) with a total 3234 person-years at risk. The incidence rate of T2D was 3000 new cases per 100,000 person-years at risk. At baseline, 63 children had T2D, and during follow-up, an additional 97 children developed incident T2D, resulting in a period prevalence of 16.8%. Incident T2D was significantly higher in females versus males (hazard ratio [HR], 1.8 [1.0-2.8]), associated with BMI z-score (HR, 1.8 [1.0-3.0]), and more severe liver histology including steatosis grade (HR, 1.3 [1.0-1.7]), and fibrosis stage (HR, 1.3 [1.0-1.5]).

CONCLUSIONS

Children with NAFLD are at high risk for existing and incident T2D. In addition to known risk factors for T2D (female and BMI z-score), severity of liver histology at the time of NAFLD diagnosis was independently associated with T2D development. Targeted strategies to prevent T2D in children with NAFLD are needed.

Research Progress on the Construction and Application of a Diabetic Zebrafish Model

Diabetes is a metabolic disease characterized by high blood glucose levels. With economic development and lifestyle changes, the prevalence of diabetes is increasing yearly. Thus, it has become an increasingly serious public health problem in countries around the world. The etiology of diabetes is complex, and its pathogenic mechanisms are not completely clear. The use of diabetic animal models is helpful in the study of the pathogenesis of diabetes and the development of drugs. The emerging vertebrate model of zebrafish has many advantages, such as its small size, large number of eggs, short growth cycle, simple cultivation of adult fish, and effective improvement of experimental efficiency. Thus, this model is highly suitable for research as an animal model of diabetes. This review not only summarizes the advantages of zebrafish as a diabetes model, but also summarizes the construction methods and challenges of zebrafish models of type 1 diabetes, type 2 diabetes, and diabetes complications. This study provides valuable reference information for further study of the pathological mechanisms of diabetes and the research and development of new related therapeutic drugs.

Isolation and characterization of lactic acid bacteria with potential probiotic activity and further investigation of their activity by α-amylase and α-glucosidase inhibitions of fermented batters

Probiotic microbiota plays a vital role in gastrointestinal health and possesses other beneficial attributes such as antimicrobial and antibiotic agents along with a significant role in the management of diabetes. The present study identifies the probiotic potential of Lactobacillus spp. isolated from three traditionally fermented foods namely, jalebi, medhu vada, and kallappam batters at biochemical, physiological, and molecular levels. By 16S rRNA gene amplification and sequencing, the isolates were identified. A similarity of >98% to Lacticaseibacillus rhamnosus RAMULAB13, Lactiplantibacillus plantarum RAMULAB14, Lactiplantibacillus pentosus RAMULAB15, Lacticaseibacillus paracasei RAMULAB16, Lacticaseibacillus casei RAMULAB17, Lacticaseibacillus casei RAMULAB20, and Lacticaseibacillus paracasei RAMULAB21 was suggested when searched for homology using NCBI database. Utilizing the cell-free supernatant (CS), intact cells (IC), and cell-free extract (CE) of the isolates, inhibitory potential activity against the carbohydrate hydrolyzing enzymes α-glucosidase and α-amylase was assessed. CS, CE, and IC of the isolates had a varying capability of inhibition against α-glucosidase (15.08 to 59.55%) and α-amylase (18.79 to 63.42%) enzymes. To assess the probiotic potential of seven isolates, various preliminary characteristics were examined. All the isolates exhibited substantial tolerance toward gastrointestinal conditions and also demonstrated the highest survival rate (> 99%), hydrophobicity (> 65%), aggregation (> 76%), adherence to HT-29 cells (> 84%), and chicken crop epithelial cells suggesting that the isolates had a high probiotic attribute. Additionally, the strains showed remarkable results in safety assessment assays (DNase and hemolytic), and antibacterial and antibiotic evaluations. The study concludes that the lactic acid bacteria (LAB) characterized possesses outstanding probiotic properties and has antidiabetic effects. In order to obtain various health advantages, LAB can be utilized as probiotic supplements.

Waist Circumference-Years Construct Analysis and the Incidence of Type 2 Diabetes: China Health and Nutrition Survey, 1997-2015

Background: Few studies have combined the degree and duration of abdominal obesity into a waist circumference-years construct for analysis. The purpose of this study was to investigate the effect of waist circumference-years on the incidence of type 2 diabetes. Methods: A total of 6616 adults from the China Health and Nutrition Survey (CHNS) were enrolled in this study from 1997. The waist circumference-years construct was represented as the sum of the upper and lower area between the waist circumference baseline (men: ≥90 cm, women: ≥85 cm) and the waist circumference line. The correlations in the study were analyzed using logistic regression. Results: The incidence of type 2 diabetes increased with increasing waist circumference-years, with an adjusted risk increase of 38% (95% CI: 31−47%) for each additional 50 waist circumference-years, and this rate was similar across gender and age groups. The area under the curve of waist circumference-years (0.743) was greatest in the receiver operating characteristic curve (ROC) analysis compared to baseline waist circumference (0.731) and the waist-height ratio (0.728) (p < 0.05). Conclusion: The waist circumference-years construct is closely associated with an increased risk of type 2 diabetes and may be a stronger predictor of type 2 diabetes risk than baseline waist circumference or the waist-height ratio.

Proinflammatory Polyphosphate Increases in Plasma of Obese Children with Insulin Resistance and Adults with Severe Type 2 Diabetes

Obesity increases the risk of insulin resistance and type 2 diabetes through increased inflammation at cellular and tissue levels. Therefore, study of the molecular elements involved in obesity-related inflammation may contribute to preventing and controlling it. Inorganic polyphosphate is a natural phosphate polymer that has recently been attracting more attention for its role in inflammation and hemostasis processes. Polyphosphates are one of the main constituents of human platelets, which are secreted after platelet activation. Among other roles, they interact with multiple proteins of the coagulation cascade, trigger bradykinin release, and inhibit the complement system. Despite its importance, determinations of polyphosphate levels in blood plasma had been elusive until recently, when we developed a method to detect these levels precisely. Here, we perform cross sectional studies to evaluate plasma polyphosphate in: 25 children, most of them with obesity and overweight, and 20 adults, half of them with severe type 2 diabetes. Our results show that polyphosphate increases, in a significant manner, in children with insulin resistance and in type 2 diabetes patients. As we demonstrated before that polyphosphate decreases in healthy overweight individuals, these results suggest that this polymer could be an inflammation biomarker in the metabolic disease onset before diabetes.

High glucose-induced ROS-accumulation in embryo-larval stages of zebrafish leads to mitochondria-mediated apoptosis

In recent decades, diabetes mellitus has become a major chronic disease threatening human health worldwide, and the age of patients tends to be younger; however, the pathogenesis remains unclear, resulting in many difficulties in its treatment. As an ideal model animal, zebrafish can simulate the processes of human diabetes well. In this study, we successfully established a model of diabetic zebrafish larvae in a previous work. Furthermore, transcriptome analysis was completed, and the results suggested that 10.59% of differentially expressed genes (DEGs) related to the apoptosis pathway need to be considered. Then, glucose-induced developmental toxicity, reactive oxygen species (ROS) accumulation, antioxidant system function, apoptosis and mitochondrial dysfunction were measured in zebrafish larvae. We hope that this study will provide valuable reference information for type 2 juvenile diabetes treatment.

Reversibility of pancreatic β-cells dysfunction after vitamin D and calcium supplementation: a pilot study in a population of obese and prepubescent North-African children

The mechanisms of diabetogenesis in children remain largely obscure. This study aimed to determine the impact of vitamin D and calcium supplementation on pancreatic β-cells function in terms of insulin secretion and sensitivity. This was a quasi-experimental study involving 30 obese and prepubescent Tunisian children (57% boys). During three months, the children received calcium and vitamin D supplementation at therapeutic doses. An oral glucose tolerance test (OGTT) was performed at the beginning and at the end of the study. The following metabolic definitions were applied: i) hyperinsulinism: insulinemia sum > 300 μ UI/ml during OGTT, ii) insulin-resistance: homeostatic model assessment of insulin-resistance > 2, iii) normal glycaemic profile: normal plasma levels during OGTT without any spike, and iv) pancreatic β-cells dysfunction reversibility: disappearance of the aforementioned disorders. The means ± standard-deviation of age and body mass index were 10.87 ± 1.9 years, and 30.17 ± 4.99 kg/m², respectively. All children were at the stage of hyperinsulinism associated with insulin-resistance. These disturbances were noted even in children having a normal glycaemic profile at OGTT. After calcium and vitamin D supplementation, glycaemic profile as well as insulin-secretion improved significantly (p < 0.0001). Hyperinsulinism and insulin-resistance decreased significantly by 56.67% (p < 0.0001) and 70.00% (p < 0.0001), respectively. Complete reversibility of these two disorders was noted in 26.6% of children. To conclude, in obese and prepubescent children, vitamin D and calcium supplementation led to the reversibility of the pancreatic β-cells dysfunction.

A performance review of novel adiposity indices for assessing insulin resistance in a pediatric Latino population

INTRODUCTION

Body mass index (BMI) percentile or BMI adjusted for age and sex is the most common anthropometric index to monitor and assess obesity in children. However, the ability of BMI to accurately predict insulin resistance (IR) in youth is debated. Determining the best method to noninvasively measure IR in the pediatric population is especially important due to the growing prevalence of type 2 diabetes mellitus (T2DM), which is more likely to develop in people with IR. Therefore, this study analyzed the performance of BMI against newer anthropometric indices in assessing IR in a pediatric Latino identifying sample.

METHODS

We studied 127 pediatric Latino participants from the Arizona Insulin Resistance (AIR) registry and performed linear regression analyses between various measures of IR and adiposity indices, including body mass index (BMI), triponderal mass index (TMI), body adiposity index (BAI), pediatric body adiposity index (pBAI), a body shape index (ABSI), abdominal volume index (AVI), waist to height ratio (WtHR) and waist to hip ratio (WHR). Log transformations of each index adjusted for age and sex and IR were used for the linear regressions. Additionally, we generated receiver operating characteristics (ROC) from logistic regressions between HOMA-IR and HOMA2IR against the same indices.

RESULTS

Using the homeostatic assessment of insulin resistance (HOMA-IR), HOMA2IR, the quantitative insulin-sensitivity check index (QUICKI), fasting serum insulin, and FPG/FSI to measure IR, we showed that BMI adjusted for age and sex performs similarly to many of the newer indices in our sample. The correlation coefficients for pBAI [R2: 0.27, 95% confidence interval: 0.88-1.81, p < 0.001] and BMI [R2: 0.27, 95% confidence interval: 0.92-1.92, p < 0.001] were the highest for HOMA-IR. Similarly, pBAI [R2: 0.29, 95% confidence interval: 0.88-1.72, p < 0.001] and BMI [R2: 0.29, 95% confidence interval: 0.93-1.83, p < 0.001] were the highest for HOMA2IR. A similar trend was observed with QUICKI, FSI, and FPG/FSI. ABSI had the lowest R ² value for all measures of IR. Area under the curve (AUC) values for the receiver operating characteristics (ROC) for HOMA-IR and HOMA2IR support these conclusions.

CONCLUSIONS

BMI adjusted for age and sex, despite its usage and simplicity, still stacks up well against newer indices in our Latino sample. Testing these indices across larger samples is necessary to generalize these findings and translate performance to adults.

Treatment of type 2 diabetes in children: what are the specific considerations?

Introduction: The number of individuals under 18 years of age with type 2 diabetes is increasing at an alarming rate worldwide. These patients are often characterized by obesity and they often experience a more rapid disease progression than adults with type 2 diabetes. Thus, focus on prevention and management of complications and comorbidities is imperative. With emphasis on weight loss and optimal glycemic control, treatment includes lifestyle changes and pharmacotherapy, which in this patient group is limited to metformin, liraglutide and insulin. In selected cases, bariatric surgery is indicated.Areas covered: This perspective article provides an overview of the literature covering pathophysiology, diagnosis, characteristics and treatment of pediatric type 2 diabetes, and outlines the gaps in our knowledge where further research is needed. The paper draws on both mechanistic studies, large scale intervention trials, epidemiological studies and international consensus statements.Expert opinion: Type 2 diabetes in pediatric patients is an increasing health care problem, and the current treatment strategies do not successfully meet the many challenges and obstacles in this patient group. Treatments must be early, intensive, multifaceted and durable. Also, prevention of obesity and type 2 diabetes in at-risk children should be addressed and prioritized on all levels.

Mori Ramulus Inhibits Pancreatic β-Cell Apoptosis and Prevents Insulin Resistance by Restoring Hepatic Mitochondrial Function

Type 2 diabetes mellitus is characterized by insulin resistance and pancreatic beta (β)-cell dysfunction. Accumulating evidence suggests that mitochondrial dysfunction may cause insulin resistance in peripheral tissues. As commercial hypoglycemic drugs have side effects, it is necessary to develop safe and effective natural compound-based hypoglycemic treatments. This study aimed to investigate the hypoglycemic effects of Mori Ramulus ethanol extract (ME) in a high-fat diet (HFD)-induced diabetes mouse model to decipher the underlying mechanisms focusing on apoptosis and mitochondrial function. ME significantly decreased tunicamycin-induced apoptotic cell death and increased insulin secretion following glucose stimulation in NIT-1 pancreatic β-cells. Tunicamycin-exposed NIT-1 pancreatic β-cells showed elevated reactive oxygen species levels and reduced mitochondrial membrane potential, which were reversed by ME treatment. ME inhibited the tunicamycin-induced apoptosis cascade in tunicamycin-exposed NIT-1 pancreatic β-cells. In HFD diabetic mice, the serum-free fatty acid and insulin levels decreased following a 15-week ME administration. Glucose and insulin tolerance tests showed that ME improved insulin sensitivity. Moreover, ME ameliorated pancreatic β-cell mass loss in diabetic mice. Finally, ME-treated HFD-fed mice showed improved hepatic mitochondrial function resulting in insulin sensitivity in target tissues. Thus, ME provides protection against pancreatic β-cell apoptosis and prevents insulin resistance by improving mitochondrial function.

Treatment options and current guidelines of care for pediatric type 2 diabetes patients: a narrative review

CONTEXT

Type 2 diabetes (T2D) mellitus, which was once considered a disease affecting adults, is a growing problem among youths. Research now shows that T2D in youths is more progressive and associated with earlier onset of complications than adult-onset T2D.

OBJECTIVES

To update practicing clinical physicians on what is currently known about pediatric T2D and share current guidelines to care for these patients.

METHODS

The authors conducted a literature review through the MEDLINE/PubMed, Google Scholar, and clinicaltrials.gov databases in July 2019 using the following search phrases: "youth-onset type 2 diabetes," "pediatric type 2 diabetes," "diabetes in youth," and "FDA-approved pediatric diabetes medications." Items published between 2010 and 2019 and written in English were included.

RESULTS

A total of 65 items were included after database review, including 44 articles, 10 FDA product inserts, six clinicaltrials.gov listings, three position statements/guideline documents, one website, and one FDA announcement.

CONCLUSIONS

There are very limited treatment options available to manage pediatric T2D. Prevention of pediatric T2D is paramount, which requires a high index of suspicion, routine screening of children and adolescents, and willingness to engage in family-based interventions for those at risk for prediabetes and T2D. Osteopathic physicians have a unique opportunity to help by applying the osteopathic principles to the whole person - including environmental, societal, and lifestyle factors - to help patients achieve their health and wellness goals.

A Model of Adolescent Sleep Health and Risk for Type 2 Diabetes

PURPOSE OF REVIEW

This paper presents a review of the current literature in support of a model explaining the relationships between sleep health and risk for type 2 diabetes in adolescents.

RECENT FINDINGS

Short sleep duration is associated with risk of developing obesity in youth. Sleep restriction increases energy expenditure, but also increases hunger, appetite, and food intake, causing positive energy balance, impacting appetite-regulating hormones, and leading to increased eating late at night. Insufficient sleep may lead to reduced physical activity and greater sedentary behaviors. In addition, short sleep duration is associated with reduced insulin sensitivity. The cumulative negative consequences of insufficient sleep increase risk for type 2 diabetes. Applications to clinical care, public policy, and future research are discussed. Insufficient sleep in adolescence increases risk for type 2 diabetes directly through impact on insulin sensitivity and indirectly through increased dietary intake, sedentary activity, and weight gain.

Effect of a high protein/low glycaemic index diet on insulin resistance in adolescents with overweight/obesity-A PREVIEW randomized clinical trial

BACKGROUND

Pubertal insulin resistance (IR) is associated with increased risk of type 2 diabetes mellitus development in adolescents with overweight/obesity.

OBJECTIVES

The PREVIEW study was a randomized parallel trial assessing the change in IR, analyzed by Homeostatic Model Assessment of IR (HOMA-IR), at 2 years after randomization to a high protein vs a moderate protein diet in adolescents with overweight/obesity. It was hypothesized that a high protein/low glycaemic index diet would be superior in reducing IR compared to a medium protein/medium GI diet, in insulin resistant adolescents with overweight or obesity.

METHODS

Adolescents with overweight/obesity and IR from the Netherlands, United Kingdom and Spain were randomized into a moderate protein/moderate GI (15/55/30En% protein/carbohydrate/fat, GI ≥ 56) or high protein/low GI (25/45/30En% protein/carbohydrate/fat, GI < 50) diet. Anthropometric and cardiometabolic parameters, puberty, dietary intake and physical activity (PA) were measured and effects on HOMA-IR were analyzed.

RESULTS

126 adolescents were included in this study (13.6 ± 2.2 years, BMI z-score 3.04 ± 0.66, HOMA-IR 3.48 ± 2.28, HP n = 68, MP n = 58). At 2 years, changes in protein intake were not significantly different between timepoints or intervention groups and no effects of the intervention on IR were observed. The retention rate was 39%, while no compliance to the diets was observed.

CONCLUSIONS

The PREVIEW study observed no effect of a high protein/low GI diet on IR in adolescents with overweight/obesity and IR because of lack of feasibility, due to insufficient retention and dietary compliance after 2 years.

Interleukin-38 increases the insulin sensitivity in children with the type 2 diabetes

The prevalence of type 2 diabetes mellitus (DM) is increasing in the children population. It is well known that inflammation contributes to the type 2 DM pathogenesis. Interleukin 38 (IL-38) is one newly identified anti-inflammatory factor. Therefore, we investigated whether the expression level of IL-38 is associated with type 2 DM in the children and the underlying mechanism. Children with recently diagnosed type 2 diabetes mellitus were recruited and studied. The healthy subjects without glucose metabolism abnormalities were used as controls. The IL-38 expression level was determined by quantitative PCR and ELISA (Enzyme-linked immunoassay). Statistic analysis showed that the IL-38 level was significantly associated with type 2 DM and insulin resistance in the children. The patients were then divided into two groups, one group sensitive to insulin therapy while the other resistant to insulin therapy. Data showed that the IL-38 was highly expressed in the group sensitive to insulin therapy. In the mice model, overexpressing the IL-38 could suppress the expression of IL-36, a pro-inflammatory factor, and also the diabetes development. Thus our results showed that higher IL-38 was associated with the increased insulin sensitive in children with type 2 DM and inhibited T2DM development in the mouse model through suppressing the function of IL-36.

Metformin Improves Peripheral Insulin Sensitivity in Youth With Type 1 Diabetes

CONTEXT

Type 1 diabetes in adolescence is characterized by insulin deficiency and insulin resistance (IR), both thought to increase cardiovascular disease risk. We previously demonstrated that adolescents with type 1 diabetes have adipose, hepatic, and muscle IR, and that metformin lowers daily insulin dose, suggesting improved IR. However, whether metformin improves IR in muscle, hepatic, or adipose tissues in type 1 diabetes was unknown.

OBJECTIVE

Measure peripheral, hepatic, and adipose insulin sensitivity before and after metformin or placebo therapy in youth with obesity with type 1 diabetes.

DESIGN

Double-blind, placebo-controlled clinical trial.

SETTING

Multi-center at eight sites of the T1D Exchange Clinic Network.

PARTICIPANTS

A subset of 12- to 19-year-olds with type 1 diabetes (inclusion criteria: body mass index ≥85th percentile, HbA1c 7.5% to 9.9%, insulin dosing ≥0.8 U/kg/d) from a larger trial (NCT02045290) were enrolled.

INTERVENTION

Participants were randomized to 3 months of metformin (N = 19) or placebo (N = 18) and underwent a three-phase hyperinsulinemic euglycemic clamp with glucose and glycerol isotope tracers to assess tissue-specific IR before and after treatment.

MAIN OUTCOME MEASURES

Peripheral insulin sensitivity, endogenous glucose release, rate of lipolysis.

RESULTS

Between-group differences in change in insulin sensitivity favored metformin regarding whole-body IR [change in glucose infusion rate 1.3 (0.1, 2.4) mg/kg/min, P = 0.03] and peripheral IR [change in metabolic clearance rate 0.923 (-0.002, 1.867) dL/kg/min, P = 0.05]. Metformin did not impact insulin suppression of endogenous glucose release (P = 0.12). Adipose IR was not assessable with traditional methods in this highly IR population.

CONCLUSIONS

Metformin appears to improve whole-body and peripheral IR in youth who are overweight/obese with type 1 diabetes.

Glycemic control and lipid outcomes in children and adolescents with type 2 diabetes

BACKGROUND

The incidence of type 2 diabetes (T2DM) in children has increased dramatically. However, limited published information is known about the glycemic control and lipid outcomes in pediatric T2DM outside of clinical trials.

OBJECTIVES

To determine the glycemic control and lipid measure outcomes at one and three- year follow-up in children with T2DM.

METHODS

A retrospective electronic medical record review of children with T2DM at the Children's Hospital of Alabama over a 12-year period.

RESULTS

There were 301 patients with a diagnosis of T2DM who had a 1-year follow-up visit, of which 184 also had a 3-year follow-up. Most patients (78%) received either insulin with metformin or insulin alone at diagnosis. At one year, 37% of the cohort achieved 'optimal glycemic control' (HbA1C ≤6.5%) and 58% of patients achieved durable glycemic control (HbA1C ≤8%). Optimal glycemic control was seen in 48 patients at 3 years. The patients treated with insulin (alone or in combination with metformin) tended to have higher HbA1C at diagnosis, but had improved lipid and glycemic outcomes at follow-up. The group treated with insulin along with metformin had significant improvements in non-HDL, HDL and TC/HDL ratios. The effects of insulin treatment on glycemic control at 3 years were not statistically significant.

CONCLUSION

With the current modality of treatment, only a minority of patients achieve optimal glycemic control at 1 and 3 years of follow-up. Studies are warranted to further elucidate the optimal therapies in the management of pediatric T2DM.

Adjustment for Waist Circumference Reveals a U-Shaped Association Between Glycated Hemoglobin Levels and Body Mass Index in Young Adults

OBJECTIVES

Body mass index (BMI) is used to assess adiposity worldwide. However, additional adjustment for waist circumference (WC), a surrogate marker of abdominal fat, may be capable of revealing a latent relationship between low body weight and glycated hemoglobin (A1C) concentration. Here, we investigated the relationship between A1C and BMI in young adults, adjusting for WC.

METHODS

We reviewed A1C, BMI, WC and other clinical data in a cross-sectional study of 26,475 apparently healthy Japanese people 20 to 39 years of age who were undergoing health check-ups.

RESULTS

Although the values of most serum parameters were high in subjects with a high BMI in both younger (20 to 29 years of age, n=10,810) and older subjects (30 to 39 years of age, n=15,665), A1C had a J-shaped relationship with BMI category in younger subjects, regardless of sex. A traditional linear model via a generalized linear model showed that in younger subjects, an inverse association of A1C level with BMI category (19 to 26.9 kg/m2 vs. ≤18.9 kg/m2) was identified after adjustment for WC. This indicates positive associations between A1C and BMI categories of ≤18.9 (beta=0.06; p<0.0001), 19.0 to 20.9 (beta=0.03; p<0.01) and ≥27.0 kg/m2 (beta=0.08; p<0.0001), in contrast to individuals with BMIs of 23.0 to 24.9 kg/m2. Similarly, in older subjects, BMIs ≤18.9 kg/m2 were associated with A1C levels but to a lesser extent (beta=0.04; p<0.05) than in younger subjects.

CONCLUSIONS

Additional adjustment of BMI for WC revealed a latent U-shaped association between A1C concentration and BMI, particularly in young adults; this deserves further investigation.

Youth with type 2 diabetes have hepatic, peripheral, and adipose insulin resistance

Adolescents with type 2 diabetes (T2D) have severe insulin resistance (IR) secondary to obesity, genetics, and puberty, and IR predicts metabolic comorbidities. Adults with T2D have multitissue IR, which has guided therapeutic developments, but this is not established in youth. We sought to assess adipose, hepatic, and peripheral insulin sensitivity in adolescents with and without T2D. Twenty-seven youth with T2D [age: 15.6 ± 0.4 yr; female: 78%; body mass index (BMI) percentile: 96.1 (52.6, 95.9), late puberty; hemoglobin A1c (HbA1c) 7.3% (6.2, 10.1)] and 21 controls of similar BMI, pubertal stage, and habitual activity were enrolled. Insulin action was measured with a four-phase hyperinsulinemic-euglycemic clamp (basal, 10, 16, and 80 mU·m-2·min-1 for studying adipose, hepatic, and peripheral IR, respectively) with glucose and glycerol isotope tracers. Total fat mass, fat-free mass, liver fat fraction, and visceral fat were measured with dual-energy x-ray absorptiometry (DXA) and MRI, respectively. Free fatty acids (FFAs), lipid profile, and inflammatory markers were also measured. Adolescents with T2D had higher lipolysis ( P = 0.012), endogenous glucose production ( P < 0.0001), and lower glucose clearance ( P = 0.002) during hyperinsulinemia than controls. In T2D, peripheral IR positively correlated to FFA ( P < 0.001), inflammatory markers, visceral ( P = 0.004) and hepatic fat ( P = 0.007); hepatic IR correlated with central obesity ( P = 0.004) and adipose IR ( P = 0.003). Youth with T2D have profound multitissue IR compared with BMI-equivalent youth without T2D. The development of multitissue interactions appears crucial to the pathogenesis of T2D. Therapeutic targets on multitissue IR may be of benefit, deserving of further research.

Too Late and Not Enough: School Year Sleep Duration, Timing, and Circadian Misalignment Are Associated with Reduced Insulin Sensitivity in Adolescents with Overweight/Obesity

OBJECTIVES

To examine the relationship between insulin resistance (IR) and sleep/circadian health in overweight/obese adolescents. We hypothesized that insufficient and delayed sleep would be associated with IR in this population.

STUDY DESIGN

Thirty-one adolescents (mean age, 16.0 ± 1.4 years; 77% female) with body mass index ≥90th percentile for age/sex were recruited from outpatient clinics at a children's hospital. Participants underwent 1 week of objective home sleep monitoring with wrist actigraphy during the academic year. A 3-hour oral glucose tolerance test was conducted, followed by in-laboratory salivary dim-light melatonin sampling every 30-60 minutes from 5 p.m. to noon the next day. Regression analyses between sleep and circadian variables with IR were examined.

RESULTS

Longer sleep time and time in bed on weekends and weekdays and earlier weekday bedtime were significantly associated with better insulin sensitivity. Participants who obtained less than the median duration of sleep per night (6.6 hours) had evidence of IR with compensatory insulin secretion compared with those obtaining ≥6.6 hours of sleep. A wider phase angle between bedtime and melatonin onset, indicating a later circadian timing of sleep onset, was significantly associated with IR.

CONCLUSIONS

Short sleep duration, later weekday bedtime, and later circadian timing of sleep were associated with IR in a cohort of adolescents with overweight/obesity during the school year. Further research is needed to better understand the physiology underlying these observations and to evaluate the impact of improved sleep and circadian health on metabolic health in this at-risk population.

Type 2 Diabetes in Latino Youth: A Clinical Update and Current Challenges

Latino youth have the highest prevalence of overweight and obesity among all ethnic groups and are disproportionally affected by pre diabetes and type 2 diabetes (T2DM). Interventions that effectively reduce the risk of pre diabetes and T2DM in this population are urgently needed. Studies have shown that without any change, 50% of Latino children and adolescents will develop T2DM. This has important public health implications. Few pharmacologic options are approved for use in the pediatric population. The largest clinical trial to date did include a significant sample of Latinos, however the intervention used metformin or rosiglitazone in addition to lifestyle management and did not show meaningful weight loss, with around half of the participants meeting criteria for treatment failure. On the other hand, a smaller trial on surgical treatment of adolescents with severe obesity and T2DM resulted in superior glycemic control, reduced weight, and improvement of other co-morbidities of T2DM in youth. Lastly, culturally tailored programs that focus on building healthy communities appear to be a promising intervention to reduce diabetes risk in Latino youth. This review provides an update on the clinical aspects of T2DM in Latino youth and focuses on management and prevention strategies.

Development of type 2 diabetes mellitus in people with intermediate hyperglycaemia

BACKGROUND

Intermediate hyperglycaemia (IH) is characterised by one or more measurements of elevated blood glucose concentrations, such as impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and elevated glycosylated haemoglobin A1c (HbA1c). These levels are higher than normal but below the diagnostic threshold for type 2 diabetes mellitus (T2DM). The reduced threshold of 5.6 mmol/L (100 mg/dL) fasting plasma glucose (FPG) for defining IFG, introduced by the American Diabetes Association (ADA) in 2003, substantially increased the prevalence of IFG. Likewise, the lowering of the HbA1c threshold from 6.0% to 5.7% by the ADA in 2010 could potentially have significant medical, public health and socioeconomic impacts.

OBJECTIVES

To assess the overall prognosis of people with IH for developing T2DM, regression from IH to normoglycaemia and the difference in T2DM incidence in people with IH versus people with normoglycaemia.

SEARCH METHODS

We searched MEDLINE, Embase, ClincialTrials.gov and the International Clinical Trials Registry Platform (ICTRP) Search Portal up to December 2016 and updated the MEDLINE search in February 2018. We used several complementary search methods in addition to a Boolean search based on analytical text mining.

SELECTION CRITERIA

We included prospective cohort studies investigating the development of T2DM in people with IH. We used standard definitions of IH as described by the ADA or World Health Organization (WHO). We excluded intervention trials and studies on cohorts with additional comorbidities at baseline, studies with missing data on the transition from IH to T2DM, and studies where T2DM incidence was evaluated by documents or self-report only.

DATA COLLECTION AND ANALYSIS

One review author extracted study characteristics, and a second author checked the extracted data. We used a tailored version of the Quality In Prognosis Studies (QUIPS) tool for assessing risk of bias. We pooled incidence and incidence rate ratios (IRR) using a random-effects model to account for between-study heterogeneity. To meta-analyse incidence data, we used a method for pooling proportions. For hazard ratios (HR) and odds ratios (OR) of IH versus normoglycaemia, reported with 95% confidence intervals (CI), we obtained standard errors from these CIs and performed random-effects meta-analyses using the generic inverse-variance method. We used multivariable HRs and the model with the greatest number of covariates. We evaluated the certainty of the evidence with an adapted version of the GRADE framework.

MAIN RESULTS

We included 103 prospective cohort studies. The studies mainly defined IH by IFG5.6 (FPG mmol/L 5.6 to 6.9 mmol/L or 100 mg/dL to 125 mg/dL), IFG6.1 (FPG 6.1 mmol/L to 6.9 mmol/L or 110 mg/dL to 125 mg/dL), IGT (plasma glucose 7.8 mmol/L to 11.1 mmol/L or 140 mg/dL to 199 mg/dL two hours after a 75 g glucose load on the oral glucose tolerance test, combined IFG and IGT (IFG/IGT), and elevated HbA1c (HbA1c5.7: HbA1c 5.7% to 6.4% or 39 mmol/mol to 46 mmol/mol; HbA1c6.0: HbA1c 6.0% to 6.4% or 42 mmol/mol to 46 mmol/mol). The follow-up period ranged from 1 to 24 years. Ninety-three studies evaluated the overall prognosis of people with IH measured by cumulative T2DM incidence, and 52 studies evaluated glycaemic status as a prognostic factor for T2DM by comparing a cohort with IH to a cohort with normoglycaemia. Participants were of Australian, European or North American origin in 41 studies; Latin American in 7; Asian or Middle Eastern in 50; and Islanders or American Indians in 5. Six studies included children and/or adolescents.Cumulative incidence of T2DM associated with IFG5.6, IFG6.1, IGT and the combination of IFG/IGT increased with length of follow-up. Cumulative incidence was highest with IFG/IGT, followed by IGT, IFG6.1 and IFG5.6. Limited data showed a higher T2DM incidence associated with HbA1c6.0 compared to HbA1c5.7. We rated the evidence for overall prognosis as of moderate certainty because of imprecision (wide CIs in most studies). In the 47 studies reporting restitution of normoglycaemia, regression ranged from 33% to 59% within one to five years follow-up, and from 17% to 42% for 6 to 11 years of follow-up (moderate-certainty evidence).Studies evaluating the prognostic effect of IH versus normoglycaemia reported different effect measures (HRs, IRRs and ORs). Overall, the effect measures all indicated an elevated risk of T2DM at 1 to 24 years of follow-up. Taking into account the long-term follow-up of cohort studies, estimation of HRs for time-dependent events like T2DM incidence appeared most reliable. The pooled HR and the number of studies and participants for different IH definitions as compared to normoglycaemia were: IFG5.6: HR 4.32 (95% CI 2.61 to 7.12), 8 studies, 9017 participants; IFG6.1: HR 5.47 (95% CI 3.50 to 8.54), 9 studies, 2818 participants; IGT: HR 3.61 (95% CI 2.31 to 5.64), 5 studies, 4010 participants; IFG and IGT: HR 6.90 (95% CI 4.15 to 11.45), 5 studies, 1038 participants; HbA1c5.7: HR 5.55 (95% CI 2.77 to 11.12), 4 studies, 5223 participants; HbA1c6.0: HR 10.10 (95% CI 3.59 to 28.43), 6 studies, 4532 participants. In subgroup analyses, there was no clear pattern of differences between geographic regions. We downgraded the evidence for the prognostic effect of IH versus normoglycaemia to low-certainty evidence due to study limitations because many studies did not adequately adjust for confounders. Imprecision and inconsistency required further downgrading due to wide 95% CIs and wide 95% prediction intervals (sometimes ranging from negative to positive prognostic factor to outcome associations), respectively.This evidence is up to date as of 26 February 2018.

AUTHORS' CONCLUSIONS

Overall prognosis of people with IH worsened over time. T2DM cumulative incidence generally increased over the course of follow-up but varied with IH definition. Regression from IH to normoglycaemia decreased over time but was observed even after 11 years of follow-up. The risk of developing T2DM when comparing IH with normoglycaemia at baseline varied by IH definition. Taking into consideration the uncertainty of the available evidence, as well as the fluctuating stages of normoglycaemia, IH and T2DM, which may transition from one stage to another in both directions even after years of follow-up, practitioners should be careful about the potential implications of any active intervention for people 'diagnosed' with IH.

Youth With Type 1 Diabetes Have Adipose, Hepatic, and Peripheral Insulin Resistance

CONTEXT

Adolescents with type 1 diabetes (T1D) have difficulty obtaining optimal glucose control, which may relate to insulin resistance (IR), especially during puberty. Moreover, IR increases the risk for cardiovascular disease, the leading cause of death in T1D. However, the tissue specificity of IR in adolescents with T1D has not been fully phenotyped.

OBJECTIVE

To assess adipose, hepatic, and peripheral insulin sensitivity in adolescents with and without T1D.

DESIGN AND SETTING

Thirty-five youth with T1D [median age, 16 (first and third quartiles, 14, 17) years; 53% female; median body mass index (BMI) percentile, 82nd (55th, 96th); late puberty; median hemoglobin A1c, 8.3% (7.3%, 9.4%)] and 22 nondiabetic youth of similar age, BMI, pubertal stage, and level of habitual physical activity were enrolled. Insulin action was measured with a four-phase hyperinsulinemic euglycemic clamp (basal and 10, 16, and 80 mU/m2/min) with glucose and glycerol isotope tracers.

RESULTS

Adolescents with T1D had a significantly higher rate of lipolysis (P < 0.0001) and endogenous glucose production (P < 0.001) and lower peripheral glucose uptake (glucose rate of disappearance, 6.9 ± 2.9 mg/kg/min for patients with T1D vs 11.3 ± 3.3 for controls; P < 0.0001) during hyperinsulinemia compared with controls. In youth with T1D, glucose rate of disappearance correlated with free fatty acid at the 80-mU/m2/min phase (P = 0.005), markers of inflammation (IL-6; P = 0.012), high-sensitivity C-reactive protein (P = 0.001), and leptin (P = 0.008)], but not hemoglobin A1c.

CONCLUSIONS

Adolescents with T1D have adipose, hepatic and peripheral IR. This IR occurs regardless of obesity and metabolic syndrome features. Youth with T1D may benefit from interventions directed at improving IR in these tissues, and this area requires further research.

Oral Glucose Tolerance Test Glucose Peak Time Is Most Predictive of Prediabetes and Hepatic Steatosis in Obese Girls

Obese adolescent girls are at increased risk for type 2 diabetes, characterized by defects in insulin secretion and action. We sought to determine if later glucose peak timing (>30 minutes), 1-hour glucose >155 mg/dl, or monophasic pattern of glucose excursion during an oral glucose tolerance test (OGTT) reflect a worse cardiometabolic risk profile. Post-pubertal overweight/obese adolescent girls without diabetes were studied (N = 88; age, 15.2 ± 0.2 years; body mass index percentile, 97.7 ± 0.5). All participants completed an OGTT and body composition measures. Thirty-two girls had a four-phase hyperinsulinemic euglycemic clamp with isotope tracers, vascular imaging, and muscle mitochondrial assessments. Participants were categorized by glucose peak timing (≤30 min = early; >30 min = late), 1-hour glucose concentration (±155 mg/dL) and glucose pattern (monophasic, biphasic). Girls with a late (N = 54) vs earlier peak (n = 34) timing had higher peak glucose (P < 0.001) and insulin (P = 0.023), HbA1c (P = 0.021); prevalence of hepatic steatosis (62% vs 26%; P = 0.003) and lower oral disposition index (P < 0.001) and glucagon-like peptide-1 response (P = 0.037). When classified by 1-hour glucose, group differences were similar to peak timing, but minimal when classified by glucose pattern. In the >155 mg/dL group only, peripheral insulin sensitivity and fasting free fatty acids were worse. A later glucose peak or >155 mg/dL 1-hour glucose predicts metabolic disease risk in obese adolescent girls. This may defect incretin effects and first phase insulin response, and muscle and adipose insulin resistance.

Oral Glucose Tolerance Test Glucose Peak Time Is Most Predictive of Prediabetes and Hepatic Steatosis in Obese Girls

Obese adolescent girls are at increased risk for type 2 diabetes, characterized by defects in insulin secretion and action. We sought to determine if later glucose peak timing (>30 minutes), 1-hour glucose >155 mg/dl, or monophasic pattern of glucose excursion during an oral glucose tolerance test (OGTT) reflect a worse cardiometabolic risk profile. Post-pubertal overweight/obese adolescent girls without diabetes were studied (N = 88; age, 15.2 ± 0.2 years; body mass index percentile, 97.7 ± 0.5). All participants completed an OGTT and body composition measures. Thirty-two girls had a four-phase hyperinsulinemic euglycemic clamp with isotope tracers, vascular imaging, and muscle mitochondrial assessments. Participants were categorized by glucose peak timing (≤30 min = early; >30 min = late), 1-hour glucose concentration (±155 mg/dL) and glucose pattern (monophasic, biphasic). Girls with a late (N = 54) vs earlier peak (n = 34) timing had higher peak glucose (P < 0.001) and insulin (P = 0.023), HbA1c (P = 0.021); prevalence of hepatic steatosis (62% vs 26%; P = 0.003) and lower oral disposition index (P < 0.001) and glucagon-like peptide-1 response (P = 0.037). When classified by 1-hour glucose, group differences were similar to peak timing, but minimal when classified by glucose pattern. In the >155 mg/dL group only, peripheral insulin sensitivity and fasting free fatty acids were worse. A later glucose peak or >155 mg/dL 1-hour glucose predicts metabolic disease risk in obese adolescent girls. This may defect incretin effects and first phase insulin response, and muscle and adipose insulin resistance.

PREVIEW (Prevention of Diabetes Through Lifestyle Intervention and Population Studies in Europe and Around the World) study in children aged 10 to 17 years: Design, methods and baseline results

Insulin resistance (IR) in adolescence is associated with type 2 diabetes mellitus [T2DM]. The PREVIEW (Prevention of Diabetes Through Lifestyle Intervention and Population Studies in Europe and Around the World) study assessed the effectiveness of a high-protein, low-glycaemic-index diet and a moderate-protein, moderate-glycaemic-index diet to decrease IR in insulin-resistant children who were overweight or obese. Inclusion criteria were age 10 to 17 years, homeostatic model assessment of IR (HOMA-IR) ≥2.0 and overweight/obesity. In 126 children (mean ± SD age 13.6 ± 2.2 years, body mass index [BMI] z-score 3.04 ± 0.66, HOMA-IR 3.48 ± 2.28) anthropometrics, fat mass percentage (FM%), metabolic characteristics, physical activity, food intake and sleep were measured. Baseline characteristics did not differ between the groups. IR was higher in pubertal children with morbid obesity than in prepubertal children with morbid obesity (5.41 ± 1.86 vs 3.23 ± 1.86; P = .007) and prepubertal and pubertal children with overweight/obesity (vs 3.61 ± 1.60, P = .004, and vs 3.40 ± 1.50, P < .001, respectively). IR was associated with sex, Tanner stage, BMI z-score and FM%. Fasting glucose concentrations were negatively associated with Baecke sport score (r = -0.223, P = .025) and positively with daytime sleepiness (r = 0.280, P = .016) independent of sex, Tanner stage, BMI z-score and FM%. In conclusion, IR was most severe in pubertal children with morbid obesity. The associations between fasting glucose concentration and Baecke sport score and sleepiness suggest these might be possible targets for diabetes prevention.

Insulin resistance is higher in prepubertal girls but switches to become higher in boys at age 16: A Cohort Study (EarlyBird 57)

BACKGROUND

The risk of type 2 diabetes is increasing in teenage girls, and is associated with their greater insulin resistance (IR).

HYPOTHESIS

We hypothesized that the adverse metabolic profile of girls (compared with boys) would persist from childhood through adolescence.

PATIENTS AND METHODS

Community-based longitudinal cohort of 292 children (147 boys) studied annually from 9 to 16 years.

MEASURES

IR (homeostasis-model-assessment-2), high-density lipoprotein-cholesterol (HDL-C), triglycerides, % body-fat (dual-energy x-ray absorptiometry), pubertal stage (age at peak height velocity), physical activity (accelerometry). Multi-level modelling established the age-related trends in IR and lipids and the influence of covariates.

RESULTS

Each year from 9 to 15 years, girls had 21% to 63% higher IR than boys (girls mean IR 0.73-1.33, boys 0.51-0.89, P < .005). At 16 years the gender difference was not significant (girls IR 0.60, boys 0.56, P = .45). Girls had lower HDL-C from 9 to 12 years, higher triglycerides from 9 to 14 years, greater adiposity throughout, and earlier puberty, but boys were more active than girls (all P < .05). After adjustment for %-fat, puberty and activity, the gender difference in IR between girls and boys aged 9 to 15 years became non-significant (IR girls 0.66-1.01, boys 0.65-1.04, P > .07). However, after adjustment at 16 years, girls' IR was 25% lower than boys' (girls 0.44, boys 0.63, P = .001), and they had 22% higher HDL-C (P < .001) and 20% lower triglycerides (P = .003).

CONCLUSIONS

The higher IR of prepubertal and early pubertal girls diminishes during late puberty, and boys begin to exhibit greater metabolic risk. Despite being leaner and more active, boys at 16 years have higher IR than girls, suggesting future higher risk for diabetes, thus we reject our hypothesis.

The role of NAFLD in cardiometabolic disease: an update

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the world, yet the complex pathogenesis remains to be fully elucidated. The prevalence of NAFLD has risen precipitously in recent years and is now a leading indication for liver transplantation. New waitlist registrants with non-alcoholic steatohepatitis–induced cirrhosis increased by 170% from 2004 to 2013. In addition, patients with NAFLD are at increased risk of both cardiovascular disease and type II diabetes. In this update, recent studies contributing to the understanding of the place of NAFLD in cardiometabolic disease will be discussed.

Paediatric type 2 diabetes in China-Pandemic, progression, and potential solutions

China is gradually taking its place as one of the world's economic giants and concurrently learning to cope with the burden of diseases that are more common in the developed world, such as paediatric type 2 diabetes mellitus. The prevalence of type 2 diabetes has been recently observed among children and adolescents in China; hence, there is a lack of information about the incidence, prevalence, pathogenesis, and pathophysiology of the disease. Diagnosis, treatment, and management have been standardized to a large degree, but there is still a need for data regarding optimal management protocols and how to achieve the best control over current state of the disease. The objective of this review is to consolidate the available information about paediatric diabetes, with a focus on the increasing prevalence of type 2 diabetes in Chinese youth. Here we emphasize the prevention strategies and have included literature with respect to pathogenesis, diagnosis, and treatment published in English and Chinese within the past 10 years.

Type 2 diabetes in adolescents and young adults

The prevalence of type 2 diabetes in adolescents and young adults is dramatically increasing. Similar to older-onset type 2 diabetes, the major predisposing risk factors are obesity, family history, and sedentary lifestyle. Onset of diabetes at a younger age (defined here as up to age 40 years) is associated with longer disease exposure and increased risk for chronic complications. Young-onset type 2 diabetes also affects more individuals of working age, accentuating the adverse societal effects of the disease. Furthermore, evidence is accumulating that young-onset type 2 diabetes has a more aggressive disease phenotype, leading to premature development of complications, with adverse effects on quality of life and unfavourable effects on long-term outcomes, raising the possibility of a future public health catastrophe. In this Review, we describe the epidemiology and existing knowledge regarding pathophysiology, risk factors, complications, and management of type 2 diabetes in adolescents and young adults.

Management of diabetes mellitus in children and adolescents: engaging in physical activity

Regular physical activity is an important component in the management of both type 1 and type 2 diabetes mellitus (T1DM and T2DM), as it has the potential to improve glycemic control, delay cardiovascular complications, and increase overall well-being. Unfortunately, many children and adolescents with diabetes do not partake in regular exercise and physical activity for multiple reasons. This review identifies the barriers to participation from the aspect of the patient, caregiver, and the healthcare provider. The management of physical activity of children and adolescents with diabetes mellitus is unique and requires an understanding of exercise physiology and how it differs in these children and adolescents from those without the condition. These individuals are at risk for important and potentially life threatening complications including, but not limited to, severe or delayed nocturnal hypoglycemia. It is essential to identify these risks as well as, monitor and manage adjustments to carbohydrate intake and insulin dosing through basal-bolus regimen or insulin pump adjustments appropriately before, during, and after the exercise activity. This review discusses these issues and also outlines differences in management between patients with T1DM and T2DM.

Insulin Resistance in Youth Without Diabetes Is Not Related to Muscle Mitochondrial Dysfunction

Context

Obesity, insulin resistance (IR), and diabetes are increasing in youth, especially in girls. IR is associated with muscle mitochondrial dysfunction in youth and adults with diabetes. However, it is unknown whether this relationship is present in youth prior to development of diabetes.

Objective

Assess IR and mitochondrial function, including sex differences, in nondiabetic youth.

Design

Cross-sectional study of youth in the Exploring Perinatal Outcomes among Children, Resistance to InSulin in Type 1 And Type 2 diabetes, and Androgens and Insulin Resistance Study cohorts.

Setting

Academic medical university.

Participants

Two hundred seventy-five youth, 13 to 19 years old [43% males: 17.1 (16.52, 17.63) years, body mass index z-score (BMI-Z) 0.36, 64.7% Tanner 5; 57% females: 17.2 (16.43, 17.67) years, BMI-Z 0.72, 78.9% Tanner 5].

Interventions

Fasting laboratories, oral glucose tolerance test, and 31P magnetic resonance spectroscopy.

Main Outcome Measures

IR [triglyceride:high-density lipoprotein (HDL) ratio, Matsuda index, and homeostasis model for insulin resistance (HOMA-IR)] and muscle mitochondrial function (adenosine 5'-diphosphate time constant and oxidative phosphorylation rate).

Results

Compared with males, females were more insulin resistant, with higher triglyceride:HDL ratio [1.95 (1.30, 2.79) vs 1.69 (1.21, 2.23), P = 0.042], HOMA-IR [3.18 (2.42, 4.39) vs 2.76 (2.02, 4.08), P = 0.035], and fasting free fatty acids (FFAs) and lower Matsuda score [3.98 (2.71, 5.96) vs 5.39 (3.43, 7.57), P < 0.001]. After adjustment for the higher BMI and Tanner stage and lower physical activity levels seen in females, there were no sex differences in mitochondrial function nor in any IR measure except FFAs. We did not find an association between measures of IR and mitochondrial function.

Conclusions

The greater IR seen in adolescent girls vs boys is mostly explained by differences in BMI and physical activity. Mitochondrial function does not appear to be related to IR in a large cohort of nondiabetic youth.

Insulin resistance in type 2 diabetes youth relates to serum free fatty acids and muscle mitochondrial dysfunction

AIMS

Insulin resistance (IR) correlates with mitochondrial dysfunction, free fatty acids (FFAs), and intramyocellular lipid (IMCL) in adults with type 2 diabetes (T2D). We hypothesized that muscle IR would relate to similar factors in T2D youth.

METHODS

Participants included 17 youth with T2D, 23 normal weight controls (LCs), and 26 obese controls (OBs) of similar pubertal stage and activity level.

RESULTS

T2D and OB groups were of similar BMI. T2D youth were significantly more IR and had higher calf IMCL and serum FFA concentrations during hyperinsulinemia. ADP time constant (ADPTC), a blood-flow dependent mitochondrial function measure, was slowed and oxidative phosphorylation rates lower in T2D. In multiple linear regression of the entire cohort, lack of FFA suppression and longer ADPTC, but not IMCL or HbA1c, were independently associated with IR.

CONCLUSION

We found that elevated FFAs and mitochondrial dysfunction are early abnormalities in relatively well-controlled youth with T2D. Further, post-exercise oxidative metabolism appears affected by reduced blood flow, and is not solely an inherent mitochondrial defect. Thus, lowering FFAs and improving mitochondrial function and blood flow may be potential treatment targets in youth with T2D.

Progression from impaired glucose tolerance to type 2 diabetes in obese children and adolescents: a 3-6-year cohort study in southern Thailand

BACKGROUND

Childhood obesity is associated with abnormal glucose metabolism and type 2 diabetes mellitus (T2DM). This study evaluated the prevalence of abnormal glucose metabolism in asymptomatic obese children and adolescents, and determined the percentage of T2DM development after 3-6 years of follow-up.

METHODS

During 2007-2013, 177 obese children and adolescents who had normal fasting plasma glucose (FPG<100 mg/dL) were given an oral glucose tolerance test (OGTT). The participants were classified into four groups: normal glucose tolerance (NGT), NGT-hyperinsulinemia (NGT-HI), impaired glucose tolerance (IGT), and diabetes mellitus (DM). Blood chemistries, including FPG, glycated hemoglobin, and lipid profiles, and liver function test were performed every 6-12 months or when the patient developed any symptom or sign indicative of diabetes.

RESULTS

Glucose metabolism alterations were detected in 81.4% of the participants: 63.8% with NGT-HI, 15.3% with IGT, and 2.3% with T2DM. The median levels of homeostasis model assessment-insulin resistance (HOMA-IR) in patients with IGT (8.63) were significantly greater than those in the patients with NGT (4.04) (p<0.01). During the follow-up, 22 patients (14.4%) developed T2DM significantly more from the IGT group (nine of 33 cases, 27.3%) than the NGT-HI group (12 of 108 cases, 11.1%) (p=0.022). The predicting parameters for T2DM conversion were weight status, body mass index (BMI), FBG, fasting insulin, alanine transaminase (ALT) levels, and HOMA-IR.

CONCLUSIONS

Glucose metabolism alteration was commonly found among obese adolescents. Factors associated with T2DM development were greater weight status and the severity of insulin resistance as shown by higher HOMA-IR levels.

Prepubertal Adiposity, Vitamin D Status, and Insulin Resistance

OBJECTIVE

To evaluate the following from prepuberty to the puberty-onset: (1) changes in serum 25-hydroxyvitamin-D (25[OH]D), adiposity, and insulin resistance (IR); (2) the effect of prepubertal adiposity on serum 25(OH)D changes; and (3) the combined effect of prepubertal obesity and suboptimal-25(OH)D on IR at puberty-onset.

METHODS

A total of 426 prepubertal children (∼54% girls) were followed during pubertal-onset assessing before and after puberty-onset serum 25(OH)D, adiposity (BMI and waist circumference) and IR indicators (homeostasis-model-assessment of IR [HOMA-IR]). Associations were tested using multiple and logistic regression models adjusted by age, gender, and seasonality.

RESULTS

At puberty-onset, mean serum 25(OH)D decreased (32.2 ± 8.9 Tanner I vs 25.2 ± 8.3 ng/mL Tanner II) and total and central obesity increased (BMI-for-age-z-score ≥2 SD [%]: 16.4 vs 22.1; waist-circumference ≥75th percentile [%]: 27.2 vs 37.1, all P < .05). Children with higher adiposity before puberty onset had higher risk of suboptimal-25(OH)D (<30 ng/mL) in Tanner II (ie, odds ratio = 2.7 [1.1-6.7] for obesity and 2.7 [1.4-5.5] for central-obesity) after adjusting for relevant covariates. Children with higher adiposity and suboptimal-25(OH)D before puberty-onset had higher HOMA-IR compared with their counterparts in Tanner II (HOMA-IR: 2.8 [2.5-3.1] if central-obese and suboptimal-25[OH]D vs 2.1 [1.9-2.3] no central-obesity and optimal-25[OH]D).

CONCLUSIONS

We found that serum 25(OH)D declined with puberty-onset, likely because of adiposity increase. Moreover, children with the combined condition of central-obesity and suboptimal-25(OH)D before puberty-onset had higher pubertal IR. These results highlight the need of ensuring adequate-25(OH)D status before pubertal-onset, particularly in obese children.

Sleep efficiency as a determinant of insulin sensitivity in overweight and obese adolescents

Insulin resistance (IR) occurs in a transient manner during puberty. Obese adolescents may be at risk for persistent IR during puberty. The objective of the study is to review the literature on the association of the anthropometry and lifestyle characteristics with insulin sensitivity in overweight and obese adolescents, and include data from a new study. Relevant papers were selected and reviewed. In addition, 137 overweight and obese adolescents (42 male/95 female, age 14.4 ± 2.3 years, BMI z-score +3.3 ± 0.7, HOMA-IR 3.4 ± 1.8) from the Centre for Overweight Adolescent and Children's Healthcare (MUMC+) were included in this study. Anthropometrics, Tanner stages, sleep characteristics, food intake behaviour and physical activity were determined, and possible associations with homeostasis model assessment of insulin resistance (HOMA-IR) were tested.

RESULTS

Overweight and obese adolescents with unfavourable fat partitioning and family history of NIDDM are at risk for persistent IR. Overweight and obese adolescents from the new cohort showed a higher HOMA-IR postpubertally. BMI z-score, age, pubertal stage and prepubertally total sleeping time (TST) and sleep efficiency (SE) were identified as significant contributors. Overweight and obese adolescents showed a persistently higher instead of transiently higher HOMA-IR during puberty, associated with BMI z-score, age, pubertal stage and prepubertally less TST and SE.

New-onset diabetes mellitus after pediatric liver transplantation

In the first five yr after liver transplant, approximately one in 10 pediatric recipients will develop NODAT. Factors associated with higher risk for NODAT have been difficult to identify due to lack of uniformity in reporting and data collection. Limited studies have reported higher risk in those who are at an older age at transplant, those with high-risk ethnic backgrounds, and in those with particular underlying conditions, such as CF and primary sclerosing cholangitis. Immunosuppressive medications, including tacrolimus, cyclosporine A, GC, and sirolimus, have been implicated as contributing to NODAT, to varying degrees. Identifying those at highest risk, appropriately screening, and diagnosing NODAT is critical to initiating timely treatment and avoiding potential complications. In the pediatric population, treatment is limited primarily to insulin, with some consideration for metformin. Children with NODAT should be monitored carefully for complications of DM, including microalbuminuria, hypertension, hyperlipidemia, and retinopathy.

Insulin Resistance, Metabolic Syndrome, and Polycystic Ovary Syndrome in Obese Youth

School nurses are well aware of the childhood obesity epidemic in the United States, as one in three youth are overweight or obese. Co-morbidities found in overweight or obese adults were not commonly found in youth three decades ago but are now increasingly "normal" as the obesity epidemic continues to evolve. This article is the second of six related articles discussing the co-morbidities of childhood obesity and discusses the complex association between obesity and insulin resistance, metabolic syndrome, and polycystic ovary syndrome. Insulin resistance increases up to 50% during puberty, which may help to explain why youth are more likely to develop co-morbidities as teens. Treatment of these disorders is focused on changing lifestyle habits, as a child cannot change his or her pubertal progression, ethnicity, or family history. School nurses and other personnel can assist youth with insulin resistance, metabolic syndrome, and polycystic ovary syndrome by supporting their efforts to make changes, reinforcing that insulin resistance is not necessarily type 2 diabetes even if the child is taking medication, and intervening with negative peer pressure.

Cardiovascular complications of type 2 diabetes in youth

The prevalence of type 2 diabetes mellitus (T2DM) in youth has increased dramatically over the past decades. The literature also suggests that the progression from an impaired glucose tolerance state to established T2DM is more rapid in youth, compared to adults. The presence of significant cardiovascular complications in youth with T2DM, including cardiac, macrovascular, and microvascular remodeling, is another major issue in this younger cohort and poses a significant threat to the healthcare system. However, this issue is only now emerging as a major public health concern, with few data to support optimal treatment targets and strategies to reduce cardiovascular disease (CVD) risk in youth with T2DM. Accordingly, the purpose of this minireview is to better understand the cardiovascular complications in youth with T2DM. We briefly describe the pathophysiology from youth studies, including oxidative stress, inflammation, renin-angiotensin aldosterone system, and epigenetics, which link T2DM and CVD. We also describe the literature concerning the early signs of CVD in youth and potential treatment options to reduce cardiovascular risk.

Serological markers of enterocyte damage and apoptosis in patients with celiac disease, autoimmune diabetes mellitus and diabetes mellitus type 2

Impairment of mucosal barrier integrity of small intestine might be causative in immune-mediated gastrointestinal diseases. We tested the markers of epithelial apoptosis - cytokeratin 18 caspase-cleaved fragment (cCK-18), and enterocyte damage - intestinal fatty acid-binding protein (I-FABP) and soluble CD14 (sCD14) in sera of patients with untreated celiac disease (CLD), those on gluten-free diet (CLD-GFD), patients with autoimmune diabetes mellitus (T1D), T1D with insulitis (T1D/INS), and diabetes mellitus type 2 (T2D). We found elevated levels of cCK-18 (P<0.001), I-FABP (P<0.01) and sCD14 (P<0.05) in CLD when compared to healthy controls. However, the levels of cCK-18 (P<0.01) and I-FABP (P<0.01) in CLD-GFD were higher when compared with controls. Interestingly, elevated levels of cCK-18 and I-FABP were found in T2D and T1D (P<0.001), and T1D/INS (P<0.01, P<0.001). Twenty-two out of 43 CLD patients were seropositive for cCK-18, 19/43 for I-FABP and 11/43 for sCD14; 9/30 of T2D patients were positive for cCK-18 and 5/20 of T1D/INS for sCD14, while in controls only 3/41 were positive for cCK-18, 3/41 for I-FABP and 1/41 for sCD14. We documented for the first time seropositivity for sCD14 in CLD and potential usefulness of serum cCK-18 and I-FABP as markers of gut damage in CLD, CLD-GFD, and diabetes.

BMI gain and insulin resistance among school-aged children: a population-based longitudinal study in the Brazilian Amazon

Investigation of the determinants of metabolic outcomes associated with non-communicable diseases is increasingly important in developing countries, but such parameters have not been explored extensively during childhood. The present study assessed the impact of weight gain, measured as BMI-for-age Z-scores, on glucose and insulin concentrations, homeostasis model assessment index of insulin resistance (HOMA-IR) values, and systolic and diastolic blood pressure during school years among Amazonian children. A population-based prospective study of 696 children aged >4 to ≤ 10 years with complete anthropometric information at baseline (51% females and 86% of mixed race) was carried out; 411 children had data on metabolic parameters after a median follow-up period of 2.0 years (range 1.7-2.6 years). During follow-up, there was a significant increase in the proportion of overweight children (BMI-for-age Z-score >1) from 10.1 to 15.8% (P= 0.003). In linear regression models adjusted for the child's sex, age, race/ethnicity, baseline household wealth, birth weight and pubertal development stage, for each unit of BMI-for-age Z-score variation during follow-up, an increase of 8.58 (95% CI 7.68, 9.60) pmol/l in fasting plasma insulin concentrations and 1.47 (95% CI 1.30, 1.66) in HOMA-IR values was observed. There was no significant impact of weight gain on glucose concentrations and systolic and diastolic blood pressure. In conclusion, we found evidence that an increase in BMI during a 2-year period affected insulin resistance during school years. Considering the significant increase in overweight in this age group, special attention should be paid to monitoring increases in BMI in children from the Brazilian Amazon.

Cross-sectional analysis of glucose metabolism in Friedreich ataxia

OBJECTIVES

To evaluate the relationship between disease features in Friedreich ataxia and aberrant glucose metabolism.

METHODS

Fasting glucose, fasting insulin and random HbA1C were obtained in 158 patients with Friedreich ataxia. Regression analysis evaluated glucose, insulin, and homeostatic model assessment (HOMA) of insulin resistance (IR) and beta-cell function (ß) in relation to age, BMI, sex, and genetic severity. Categorical glucose values were analyzed in relation to other FRDA-associated disease characteristics.

RESULTS

In the FRDA cohort, age and GAA repeat length predicted fasting glucose and HbA1c levels (accounting for sex and BMI), while insulin and HOMA-IR were not predicted by these parameters. Within the cohort, average BMI was consistently lower than the national average by age and was marginally associated with insulin levels and HOMA-IR. Within juvenile subjects, insulin and HOMA-IR were predicted by age. Controlling for age and genetic severity, diabetes-related measures were not independent predictors of any quantitative measure of disease severity in FRDA. Glucose handling properties were also predicted by the presence of a point mutation, with 40% of individuals heterozygous for point mutations having diabetes, compared to 4.3% of subjects who carried two expanded GAA repeats.

INTERPRETATION

In FRDA, aberrant glucose metabolism is linked to increasing age, longer GAA repeat length on the shorter allele, frataxin point mutations, and increasing BMI. The effect of age to some degree may be mediated through changes in BMI, with increasing age associated with increases in BMI, and with HOMA-IR and insulin increases in children.

Reliable Assessment of Insulin Resistance in Children

Obesity is on the rise in the pediatric population. Obese individuals are at risk for insulin resistance, and this in combination with impaired β-cell function can result in type 2 diabetes. The diagnosis of insulin resistance is made in clinical practice by using estimates of insulin sensitivity. Scientific evidence regarding the evaluation of insulin resistance in children has revealed conflicting conclusions.