The role of glycemia in insulin resistance in youth with type 1 and type 2 diabetes

Managing type 1 diabetes in children and young people: challenges and solutions

Type 1 diabetes is the most common form of diabetes in school-age children. Effective management and self-management at home and during school hours are essential to improve the quality of life of children and young people and reduce their risk of developing complications such as cardiovascular disease and kidney disease. There are, however, multiple barriers to effective management and self-management, notably in adolescence. Interventions, education and support based on clear psychoeducational principles improve the outcomes of children and young people. This article explores type 1 diabetes including its causes and risk factors, presentation and diagnosis, complications and comorbidities, and treatment and management. It focuses in particular on the role of nurses in supporting self-management and on the challenges of type 1 diabetes care in school.

A combination of metformin and insulin improve cardiovascular and cerebrovascular risk factors in individuals with type 1 diabetes mellitus

BACKGROUND

This study aims to further clarify whether the addition of metformin to insulin treatment improve cardiovascular and cerebrovascular risk factors in individuals with T1DM.

METHODS

Electronic databases were searched for randomized controlled trials in which the efficacy and safety of metformin were compared with those of a placebo for risk factors of cardiovascular and cerebrovascular disease among individuals with T1DM, and a meta-analysis was conducted.

RESULTS

Thirteen cardiovascular studies were identified. In the metformin group, mean carotid intimal media thickness was significantly reduced by 0.03 mm, ascending aortic pulse wave velocity by 6.3 m/s, descending aortic wall shear stress by 1.77 dyn/cm² (P = 0.02), insulin daily dose by 0.05 U/kg/d, body weight by 2.27 kg, fat-free mass by 1.32 kg, body mass index by 0.58 kg/m², hip circumference by 0.29 m, and low-density lipoprotein by 0.16 mmol/L, all above are P < 0.05. In the metformin group, flow-mediated dilation was increased by 1.29 %, glucose infusion rate/insulin by 18.22 mg/(kg⋅min)/μIU/μL, and waist-to-hip ratio by 0.02, all above are P < 0.00001. The metformin group showed no differences in blood pressure, reactive hyperemia index, waist circumference, triglyceride, total cholesterol, high-density lipoprotein cholesterol, or body mass index Z score. For cerebrovascular studies were identified. But none of them had a risk factor assessment.

CONCLUSIONS

Metformin can ameliorate cardiovascular and cerebrovascular risk factors through non-hypoglycemic multiple pathways in individuals with T1DM.

Technological Ecological Momentary Assessment Tools to Study Type 1 Diabetes in Youth: Viewpoint of Methodologies

Type 1 diabetes (T1D) is one of the most common chronic childhood diseases, and its prevalence is rapidly increasing. The management of glucose in T1D is challenging, as youth must consider a myriad of factors when making diabetes care decisions. This task often leads to significant hyperglycemia, hypoglycemia, and glucose variability throughout the day, which have been associated with short- and long-term medical complications. At present, most of what is known about each of these complications and the health behaviors that may lead to them have been uncovered in the clinical setting or in laboratory-based research. However, the tools often used in these settings are limited in their ability to capture the dynamic behaviors, feelings, and physiological changes associated with T1D that fluctuate from moment to moment throughout the day. A better understanding of T1D in daily life could potentially aid in the development of interventions to improve diabetes care and mitigate the negative medical consequences associated with it. Therefore, there is a need to measure repeated, real-time, and real-world features of this disease in youth. This approach is known as ecological momentary assessment (EMA), and it has considerable advantages to in-lab research. Thus, this viewpoint aims to describe EMA tools that have been used to collect data in the daily lives of youth with T1D and discuss studies that explored the nuances of T1D in daily life using these methods. This viewpoint focuses on the following EMA methods: continuous glucose monitoring, actigraphy, ambulatory blood pressure monitoring, personal digital assistants, smartphones, and phone-based systems. The viewpoint also discusses the benefits of using EMA methods to collect important data that might not otherwise be collected in the laboratory and the limitations of each tool, future directions of the field, and possible clinical implications for their use.

The changing face of paediatric diabetes

The purpose of this review is to provide an update on the changing face of paediatric type 1 diabetes and type 2 diabetes. Paediatric diabetes is on the rise, with extensive research dedicated to understanding its pathophysiology, comorbidities and complications. As obesity continues to increase among all youth, differentiating between type 1 diabetes and type 2 diabetes has become increasingly difficult but remains important for optimising treatment, anticipating complications and predicting disease risk. Novel treatments are emerging, with the ultimate goal being to achieve glycaemic control, limit weight gain, improve quality of life and reduce comorbidities. In this review, we focus on updates regarding the epidemiology, clinical presentation, comorbidities and complications of paediatric type 1 diabetes and type 2 diabetes and conclude with current and emerging treatments.

Metformin Improves Insulin Sensitivity and Vascular Health in Youth With Type 1 Diabetes Mellitus

BACKGROUND

Cardiovascular disease is the leading cause of mortality in type 1 diabetes mellitus (T1DM) and relates strongly to insulin resistance (IR). Lean and obese adolescents with T1DM have marked IR. Metformin improves surrogate markers of IR in T1DM, but its effect on directly measured IR and vascular health in youth with T1DM is unclear. We hypothesized that adolescents with T1DM have impaired vascular function and that metformin improves this IR and vascular dysfunction.

METHODS

Adolescents with T1DM and control participants underwent magnetic resonance imaging of the ascending (AA) and descending aorta to assess pulse wave velocity, relative area change, and maximal (WSS_MAX) and time-averaged (WSS_TA) wall shear stress. Participants with T1DM also underwent assessment of carotid intima-media thickness by ultrasound, brachial distensibility by DynaPulse, fat and lean mass by dual-energy x-ray absorptiometry, fasting laboratories after overnight glycemic control, and insulin sensitivity by hyperinsulinemic-euglycemic clamp (glucose infusion rate/insulin). Adolescents with T1DM were randomized 1:1 to 3 months of 2000 mg metformin or placebo daily, after which baseline measures were repeated.

RESULTS

Forty-eight adolescents with T1DM who were 12 to 21 years of age (40% body mass index [BMI] ≥90th percentile; 56% female) and 24 nondiabetic control participants of similar age, BMI, and sex distribution were enrolled. Adolescents with T1DM demonstrated impaired aortic health compared with control participants, including elevated AA and descending aorta pulse wave velocity, reduced AA and descending aorta relative area change, and elevated AA and descending aorta WSS_MAX and WSS_TA. Adolescents with T1DM in the metformin versus placebo group had improved glucose infusion rate/insulin (12.2±3.2 [mg·kg^-1·min^-1]/μIU/μL versus -2.4±3.6 [mg·kg^-1·min^-1]/μIU/μL, P=0.005; 18.6±4.8 [mg·lean kg^-1·min^-1]/μIU/μL versus -3.4±5.6 [mg·lean kg^-1·min^-1]/μIU/μL, P=0.005) and reduced weight (-0.5±0.5 kg versus 1.6±0.5 kg; P=0.004), BMI (-0.2±0.15 kg/m² versus 0.4±0.15 kg/m²; P=0.005), and fat mass (-0.7±0.3 kg versus 0.6±0.4 kg; P=0.01). Glucose infusion rate/insulin also improved in normal-weight participants (11.8±4.4 [mg·kg^-1·min^-1]/μIU/μL versus -4.5±4.4 [mg·kg^-1·min^-1]/μIU/μL, P=0.02; 17.6±6.7 [mg·lean kg^-1·min^-1]/μIU/μL versus -7.0±6.7 [mg·lean kg^-1·min^-1]/μIU/μL, P=0.02). The metformin group had reduced AA WSS_MAX (-0.3±0.4 dyne/cm² versus 1.5±0.5 dyne/cm²; P=0.03), AA pulse wave velocity (-1.1±1.20 m/s versus 4.1±1.6 m/s; P=0.04), and far-wall diastolic carotid intima-media thickness (-0.04±0.01 mm versus -0.00±0.01 mm; P=0.049) versus placebo.

CONCLUSIONS

Adolescents with T1DM demonstrate IR and impaired vascular health compared with control participants. Metformin improves IR, regardless of baseline BMI, and BMI, weight, fat mass, insulin dose, and aortic and carotid health in adolescents with T1DM. Metformin may hold promise as a cardioprotective intervention in T1DM.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01808690.

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.

The effect of cassia seed extract on the regulation of the LKB1-AMPK-GLUT4 signaling pathway in the skeletal muscle of diabetic rats to improve the insulin sensitivity of the skeletal muscle

BACKGROUND

This study aimed to observe the hypoglycemic effect of cassia seed extract in rats with type-2 diabetes mellitus and its effect on reducing insulin resistance in the skeletal muscle.

METHODS

50 rats were randomly divided into the normal, model, high-dose, middle-dose, and low-dose groups of cassia seed extract (n = 10 each). A high-fat diet combined with streptozotocin administration was adopted to build type 2 diabetes models. The cassia seed extract groups were fed different concentrations cassia seed extract while the normal and model groups were fed the same volume of normal saline. The weight, FINS, GIR, insulin tolerance, blood glucose and blood lipid level, oxidative stress indices and expressions related to the LKB1-AMPK-GLUT4 pathway were detected and compared between the two groups.

RESULTS

Compared with the normal group, the model group showed lower weight, glucose infusion rate and expressions related to LKB1-AMPK-GLUT4 pathway and higher FINS, insulin tolerance, blood glucose and blood lipid level and oxidative stress indices (all P < 0.05). Compared with the model group, higher weight, glucose infusion rate and expressions related to LKB1-AMPK-GLUT4 pathway and lower FINS, insulin tolerance, blood glucose and blood lipid level and oxidative stress indices were observed in all groups that were administered cassia see extract (all P < 0.05).

CONCLUSION

Cassia seed extract could noticeably improve the insulin resistance of diabetic rats and enhance the insulin sensitivity of their skeletal muscles. Its mechanism may be related to damage repair of the LKB1-AMPK-GLUT4 signaling pathway and oxidative stress in the skeletal muscle.

Prevalence of underweight, overweight, and obesity in children and adolescents with type 1 diabetes: Data from the international SWEET registry

OBJECTIVE

To assess the prevalence of underweight (UW), overweight (OW), and obesity in children and adolescents with type 1 diabetes (T1D).

METHODS

An international cross-sectional study including 23 026 T1D children (2-18 years, duration of diabetes ≥1 year) participating in the SWEET prospective, multicenter diabetes registry. Body mass index SD score (BMI-SDS) was calculated using the World Health Organization BMI charts. Children were categorized as UW (BMI-SDS < -2SD), OW (+1SD < BMI-SDS ≤ +2SD), and obese (OB) (BMI-SDS > +2SD). Hierarchic regression models were applied with adjustment for sex, age, and duration of diabetes.

RESULTS

The prevalence of UW, OW, and obesity was: 1.4%, 22.3%, and 7.3% in males and 0.6%, 27.2%, and 6.8% in females. Adjusted BMI-SDS was significantly higher in females than in males (mean ± SEM: 0.54 ± 0.05 vs 0.40 ± 0.05, P < 0.0001). In males, BMI-SDS significantly decreased by age (P < 0.0001) in the first three age categories 0.61 ± 0.06 (2 to <10 years), 0.47 ± 0.06 (10 to <13 years), 0.34 ± 0.05 (13 to <16 years). In females, BMI-SDS showed a U-shaped distribution by age (P < 0.0001): 0.54 ± 0.04 (2 to <10 years), 0.39 ± 0.04 (10 to <13 years), 0.55 ± 0.04 (13 to <16 years). BMI-SDS increased by diabetes duration (<2 years: 0.38 ± 0.05, 2 to <5 years: 0.44 ± 0.05, and ≥5 years: 0.50 ± 0.05, P < 0.0001). Treatment modality did not affect BMI-SDS. Adjusted HbA1c was significantly higher in females than in males (8.20% ± 0.10% vs 8.06% ± 0.10%, P < 0.0001). In both genders, the association between HbA1c and BMI-SDS was U-shaped with the highest HbA1c in the UW and obesity groups.

CONCLUSIONS

The high rate of OW and obesity (31.8%) emphasize the need for developing further strategies to prevent and treat excess fat accumulation in T1D.

Macrovascular disease and risk factors in youth with type 1 diabetes: time to be more attentive to treatment?

Cardiovascular disease remains the leading cause of mortality in patients with type 1 diabetes. Although cardiovascular disease complications are rare until adulthood, pathology and early markers can manifest in adolescence. Whereas advances have been made in the management of microvascular complications of type 1 diabetes, similar progress in reducing macrovascular complications has not been made. The reasons for the absence of progress remain incompletely understood, but most likely relate to the long time needed for cardiovascular disease to manifest clinically and hence for risk factor management to show a clinical benefit, thus allowing inertia to prevail for diagnosis and particularly for targeting risk factors. In this Review, we summarise paediatric data on traditional and novel risk factors of cardiovascular disease, provide an overview of data from previous and current clinical trials, discuss future directions in cardiovascular disease research for paediatric patients with type 1 diabetes, and advocate for the early identification and treatment of cardiovascular disease risk factors as recommended in multiple guidelines.

Achieving ADA/ISPAD clinical guideline goals is associated with higher insulin sensitivity and cardiopulmonary fitness in adolescents with type 1 diabetes: Results from RESistance to InSulin in Type 1 ANd Type 2 diabetes (RESISTANT) and Effects of MEtformin on CardiovasculaR Function in AdoLescents with Type 1 Diabetes (EMERALD) Studies

OBJECTIVE

Most youth with type 1 diabetes do not meet the American Diabetes Association (ADA) and International Society for Pediatric and Adolescent Diabetes (ISPAD) targets for hemoglobin A1c (HbA1c), blood pressure (BP), lipids, and body mass index (BMI). We hypothesized that ISPAD/ADA goal achievement would be associated with better insulin sensitivity (IS) and cardiopulmonary fitness.

METHODS

IS was quantified as glucose infusion rate (GIR) from a hyperinsulinemic-euglycemic clamp in youth with type 1 diabetes from the RESistance to InSulin in Type 1 ANd Type 2 diabetes (RESISTANT) (n = 86) and Effects of MEtformin on CardiovasculaR Function in AdoLescents with Type 1 Diabetes (EMERALD) (n = 41) cohorts (n = 127; age 15.7 ± 2.2 years, 52% girls). Cardiopulmonary fitness was measured as peak oxygen consumption (VO₂ peak/kg) during upright (RESISTANT) or supine (EMERALD) cycle ergometry and were stratified by cycle type. Goal achievement was defined as HbA1c < 7.5%, BP < 90th percentile, LDL-cholesterol < 100 mg/dL, HDL-cholesterol > 35 mg/dL, triglycerides < 150 mg/dL and BMI < 85th percentile. Participants were stratified into 3 groups: achieving 0-3 goals (n = 52), 4 goals (n = 48), and 5-6 goals (n = 27). Differences between groups were examined with generalized linear models.

RESULTS

IS was lower in youth who met 0-3 goals (5.2 ± 3.4 mg/kg/min) vs those who met 4 goals (7.4 ± 4.1 mg/kg/min, P = .04) and those who met 5-6 goals (8.5 ± 4.3 mg/kg/min, P = .003), and remained significant after adjustments for sex and diabetes duration. Upright VO₂ peak was lower in youth who met 0-3 goals (25.8 ± 4.6 mL/kg/min) vs those who met 4 goals (33.0 ± 7.8 mL/kg/min, P = .01) and those who met 5-6 goals (33.2 ± 4.4 mL/kg/min, P = .004). Similar and significant relationships were observed in EMERALD participants for supine VO₂ peak.

CONCLUSIONS

ADA/ISPAD goal achievement was associated with greater IS and cardiopulmonary fitness.

Use of Continuous Glucose Monitoring in Youth-Onset Type 2 Diabetes

PURPOSE OF REVIEW

Continuous glucose monitoring (CGM) technology has long been accepted as a tool for managing glycemia in type 1 diabetes (T1D) and is receiving increased attention as a tool for monitoring glucose patterns in patients with other forms of diabetes, in particular type 2 diabetes (T2D). Recent studies in adults with T2D have shown benefits of CGM in the investigation of glycemic variability, as well as utility as a tool for improving glycemic control. The literature on CGM use in youth-onset T2D, however, is sparse. This paper reviews the various roles for CGM in T2D, with a focus on published reports of CGM use in youth-onset T2D. The gaps in knowledge are highlighted, along with a discussion regarding need for future studies of potential applications for CGM in this younger population.

RECENT FINDINGS

CGM systems provide insight into glycemic abnormalities in obese youth with and at risk for T2D. This technology has enabled examination of the relationship between free-living glycemic profiles and traditional diabetes screening tests, as well as markers of cardiometabolic risk in this high-risk population. Investigators are incorporating CGM technology into the study of T2D in youth, but interventional studies of CGM as a tool for glycemic control in youth-onset T2D are limited. Youth with T2D face a more aggressive disease than adults with T2D, and further studies utilizing advances in glucose monitoring technology to improve outcomes in this population are needed.