Prevalence of arterial stiffness in adolescents with type 2 diabetes in the TODAY cohort: Relationships to glycemic control and other risk factors

Impact of youth onset type 2 diabetes during pregnancy on microvascular and cardiac outcomes

AIMS

To examine the impact of pregnancy on microvascular and cardiovascular measures in women with youth-onset T2D.

METHODS

Microvascular and cardiovascular measures were compared in in a cohort of 116 women who experienced a pregnancy of ≥ 20 weeks gestation and 291 women who did not among women in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study.

RESULTS

Cox regression models adjusted for participant characteristics at baseline including age, race/ethnicity, household income, diabetes duration, HbA1c (>6%), and BMI, demonstrated those who experienced pregnancy had 2.76 (1.38-5.49; p = 0.004) fold increased risk of hyperfiltration (eGFR ≥ 135 ml/min/1.73 m2), compared to those without a pregnancy. No differences were observed in rates of retinopathy (48.9% vs. 41.1%) or neuropathy (23.3% vs. 16.3%) in women who experienced pregnancy vs. women who did not, respectively. In fully adjusted models, pregnancy did not impact changes in echocardiographic or arterial stiffness compared to changes in women who were never pregnant.

CONCLUSIONS

These results indicate that pregnancy increases the risk of hyperfiltration in women with youth-onset T2D, but not other micro or macrovascular complications. The rates of vascular complications are very high in youth-onset T2D potentially obscuring micro- and macrovascular changes attributable to pregnancy.

CLINICAL TRIAL INFORMATION

ClinicalTrials.gov numbers,NCT01364350andNCT02310724.

Managing type 2 diabetes in children and young people: challenges and solutions

Growing numbers of children and young people are diagnosed with type 2 diabetes, partly due to the obesogenic environment they grow up in. The increasing prevalence of type 2 diabetes is seen particularly in adolescent girls and in children and young people of non-white ethnic backgrounds. There are numerous challenges relating to the diagnosis, treatment and management of type 2 diabetes in children and young people, notably the fact that the condition can lead to serious complications and often triggers high levels of anxiety and stress in patients and families. This article outlines the challenges faced by children and young people with type 2 diabetes, their families and carers, and suggests ways in which nurses can support them with the aim of achieving optimal management and self-management.

Is There a Role for Imaging Youth at Risk of Atherosclerosis?

PURPOSE OF REVIEW

Cardiovascular (CV) risk factors such as dyslipidemia, hypertension, diabetes, and obesity are associated with an increased risk for CV events in adults. Noninvasive measures of vascular health are associated with these CV events and can potentially help risk stratify children with CV risk factors. The purpose of this review is to summarize recent literature regarding vascular health in children with cardiovascular risk factors.

RECENT FINDINGS

Adverse changes in pulse wave velocity, pulse wave analysis, arterial distensibility, and carotid intima-media thickness are seen in children with CV risk factors supporting potential utility in risk stratification. Assessing vascular health in children can be challenging due to growth-related changes in vasculature, multiple assessment modalities, and differences in normative data. Vascular health assessment in children with cardiovascular risk factors can be a valuable tool for risk stratification and help identify opportunities for early intervention. Future areas of research include increasing normative data, improving conversion of data between different modalities, and increasing longitudinal studies in children linking childhood risk factors to adult CV outcomes.

Longitudinal Changes in Arterial Stiffness and Heart Rate Variability in Youth-Onset Type 1 Versus Type 2 Diabetes: The SEARCH for Diabetes in Youth Study

OBJECTIVE

We compared arterial stiffness and heart rate variability (HRV) over time by diabetes type and determined the risk factors associated with worsening arterial stiffness and HRV in young adults with youth-onset diabetes.

RESEARCH DESIGN AND METHODS

Arterial stiffness (pulse wave velocity, augmentation index) and six indices of heart rate variability were measured twice, 4.5 years apart, among participants with either youth-onset type 1 or type 2 diabetes in the SEARCH for Diabetes in Youth study. Multivariable linear regression models were used to assess risk factors associated with arterial stiffness and HRV at follow-up.

RESULTS

Of 1,159 participants studied, 949 had type 1 diabetes (mean age 17.1 ± 4.7 years, 60.3% non-Hispanic White, 55% female) and 210 had type 2 diabetes (mean age 22.1 ± 3.5 years, 23.8% non-Hispanic White, 71% female) at initial assessment when diabetes duration was 7.9 years (both groups). Participants with type 2 versus type 1 diabetes had greater arterial stiffness and more abnormalities in HRV at initial and follow-up assessment and a greater change over time (all P < 0.05). Risk factors associated with worse arterial stiffness and HRV at follow-up in both types of diabetes included higher blood pressure, hemoglobin A1c, waist circumference, and triglycerides over time and longer diabetes duration.

CONCLUSIONS

Arterial stiffness and HRV worsened over time with greater changes among participants with type 2 versus type 1 diabetes and among those with features of the metabolic syndrome. The risk factor profile documents potentially modifiable pathways to prevent or limit cardiovascular complications in young adults with youth-onset diabetes.

Association of early-onset Type 2 diabetes with cognitive impairment is partially mediated by increased pulse pressure

AIMS

Type 2 diabetes mellitus (T2DM) has been shown to be associated with cognitive decline and dementia. As earlier onset of diabetes implies a longer disease duration and an increased risk to complications, we sought to investigate the effect of T2DM onset on cognitive function of our patients.

METHODS

We administered the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to T2DM patients aged 45-85 from our SMART2D cohort. We assessed the association of the T2DM onset age (both continuous and stratified into 3 groups: early-onset ≤40 (n = 326), middle-aged onset 41-64 (n = 703) and late-onset ≥65 years old (n = 38)) and RBANS cognitive indices in 1067 patients. Potential mediation of this association by vascular compliance using mediation analysis was investigated.

RESULTS

T2DM onset associates significantly with RBANS total score. Patients with early T2DM onset have lower RBANS total score as compared to patients with middle-aged onset (β = -2.01, p = 0.0102) and those with late-onset (β = -5.80, p = 0.005). This association was partially mediated by pulse pressure index (25.8%), with indirect effect of 0.028 (Bootstrapped-CI: 0.008-0.047).

CONCLUSIONS

Association of early-onset T2DM with cognitive impairment is partly mediated by diminished vascular compliance. Appropriate screening and assessment of cognitive function is important for early intervention and management of cognitive impairment.

Relationship between Arterial Stiffness and Subsequent Cardiac Structure and Function in Young Adults with Youth-Onset Type 2 Diabetes: Results from the TODAY Study

BACKGROUND

Higher arterial stiffness may contribute to future alterations in left ventricular systolic and diastolic function. We tested this hypothesis in individuals with youth-onset type 2 diabetes from the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study.

METHODS

Arterial stiffness (pulse wave velocity [carotid-femoral, femoral-foot, and carotid-radial], augmentation index, brachial distensibility) was measured in 388 participants with type 2 diabetes (mean age, 21 years; diabetes duration, 7.7 ± 1.5 years). To reflect overall (composite) vascular stiffness, the five arterial stiffness measures were aggregated. An echocardiogram was performed in the same cohort 2 years later. Linear regression models assessed whether composite arterial stiffness was associated with left ventricular mass index or systolic and diastolic function, independent of age, sex, race/ethnicity, current cigarette smoking, and long-term exposure (time-weighted mean values over 9.1 years) of hemoglobin A1c, blood pressure, and body mass index. Interactions among arterial stiffness and time-weighted mean hemoglobin A1c, blood pressure, and body mass were also examined.

RESULTS

After adjustment, arterial stiffness remained significantly associated with left ventricular mass index and diastolic function measured by mitral valve E/Em, despite attenuation by time-weighted mean body mass index. A significant interaction revealed a greater adverse effect of composite arterial stiffness on mitral valve E/Em among participants with higher levels of blood pressure over time. Arterial stiffness was unrelated to left ventricular systolic function.

CONCLUSIONS

The association of higher arterial stiffness with future left ventricular diastolic dysfunction suggests the path to future heart failure may begin early in life in this setting of youth-onset type 2 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00081328.

Cerebral blood flow is lower in youth with type 2 diabetes compared to obese controls: A pilot study

AIM

The cerebral vasculature may be susceptible to the adverse effects of type 2 diabetes. In this pilot study, we compared cerebral blood flow (CBF) in youth with type 2 diabetes to obese, euglycemic controls, and explored the association between CBF and a non-invasive measure of atherosclerosis, carotid intima-medial thickness (IMT).

METHODS

Global and regional CBF were compared between youth with type 2 diabetes (mean age 16.7 ± 2.0 years, n = 20) and age, race, and sex similar obese youth without diabetes (17.4 ± 1.9 years, n = 19) using arterial spin labeling magnetic resonance imaging. Mean CBF values were compared between groups. Voxel-wise results were evaluated for statistical significance (p < 0.05) after adjustment for multiple comparisons. Carotid IMT in the type 2 diabetes group was correlated with CBF.

RESULTS

Compared to obese controls, the type 2 diabetes group had significantly lower global CBF (49.7 ± 7.2 vs. 63.8 ± 11.5 ml/gm/min, p < 0.001). Significantly lower CBF was observed in multiple brain regions for the type 2 diabetes group, while no regions with higher CBF were identified. In the type 2 diabetes group, carotid IMT was inversely correlated with CBF, both globally (r = -0.70, p = 0.002) and in regional clusters.

CONCLUSIONS

In this pilot study, lower CBF was seen in youth with type 2 diabetes compared to youth with obesity and IMT was inversely correlated with CBF. Cerebrovascular impairment may be present in youth with type 2 diabetes. These findings could represent a mechanistic link to explain previously reported brain volume and neurocognitive differences.

Cardiovascular risk factor progression in adolescents and young adults with youth-onset type 2 diabetes

AIMS

Youth-onset type 2 diabetes (T2D) confers a high risk of early adverse cardiovascular morbidity. We describe the cumulative incidence and prevalence of cardiovascular risk factors over time and examine relationships with diabetes progression in young adults with youth-onset T2D from the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study.

METHODS

Longitudinal data was used to evaluate the relationships between hypertension, LDL-C dyslipidemia, hypertriglyceridemia, and smoking with risk factors in 677 participants.

RESULTS

Baseline mean age was 14 ± 2 years and mean follow-up 10.2 ± 4.5 years. The 14-year cumulative incidence of hypertension, LDL-C dyslipidemia, and hypertriglyceridemia was 59%, 33%, and 37% respectively. Average prevalence of reported smoking was 23%. Male sex, non-Hispanic white race/ethnicity, obesity, poor glycemic control, lower insulin sensitivity, and reduced beta-cell function were significantly associated with an unfavorable risk profile. At end of follow-up, 54% had ≥2 cardiovascular risk factors in addition to T2D.

CONCLUSIONS

Cardiovascular risk factor incidence and prevalence was high over a decade of follow-up in young adults with youth-onset T2D. Glucose control and management of cardiovascular risk factors is critical in youth with T2D for prevention of cardiovascular morbidity and mortality.

Longitudinal changes in vascular stiffness and heart rate variability among young adults with youth-onset type 2 diabetes: results from the follow-up observational treatment options for type 2 diabetes in adolescents and youth (TODAY) study

AIMS

(1) To describe changes in arterial stiffness and heart rate variability (HRV) over a 5-year interval, (2) examine changes by sex and race-ethnicity, and (3) evaluate the risk factors associated with the longitudinal changes in arterial stiffness and HRV.

METHODS

Participants with youth-onset type 2 diabetes enrolled in the observational follow-up phase of the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) clinical trial had arterial stiffness [(pulse wave velocity, augmentation index, brachial distensibility] and six indices of HRV measured 5 years apart. Multivariable linear regression models assessed risk factors associated with changes in the outcomes over time.

RESULTS

At initial vascular assessment, the 304 participants were a mean age of 21 years, 34% male, and had a mean diabetes duration of 8 years. In more than half the cohort pulse wave velocity, augmentation index and HRV increased over 5 years (p<0.01). Brachial distensibility did not change. There were no differences in the 5-year change by race/ethnicity except for a single HRV measure, where non-Hispanic Blacks had greater worsening of parasympathetic function compared to non-Hispanic Whites, p = 0.008. Blood pressure was related to greater worsening in augmentation index and pulse wave velocity. Higher hemoglobin A1c over time was related to worsening pulse wave velocity and HRV.

CONCLUSIONS

Arterial stiffness and HRV worsened over 5 years. Blood pressure and glycemic control may be potential targets to influence adverse changes in arterial stiffness and HRV in young adults with youth-onset type 2 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00081328.

Spectrum of Phenotypes and Causes of Type 2 Diabetes in Children

Several factors, including genetics, family history, diet, physical activity, obesity, and insulin resistance in puberty, appear to increase the risk of type 2 diabetes in youth. Youth-onset type 2 diabetes is often thought of as a single entity but rather exists as a spectrum of disease with differences in presentation, metabolic characteristics, clinical progression, and complication rates. We review what is currently known regarding the risks associated with developing type 2 diabetes in youth. Additionally, we focus on the spectrum of phenotypes of pediatric type 2 diabetes, discuss the pathogenic underpinnings and potential therapeutic relevance of this heterogeneity, and compare youth-onset type 2 diabetes with type 1 diabetes and adult-onset type 2 diabetes. Finally, we highlight knowledge gaps in prediction and prevention of youth-onset type 2 diabetes.

Effect of glycemic control on markers of subclinical atherosclerosis in patients with type 2 diabetes mellitus: A review

Cardiovascular disease is the predominant cause of death in type 2 diabetes mellitus (T2DM). Evidence suggests a strong association between duration and degree of hyperglycemia and vascular disease. However, large trials failed to show cardiovascular benefit after intensive glycemic control, especially in patients with longer diabetes duration. Atherosclerosis is a chronic and progressive disease, with a long asymptomatic phase. Subclinical atherosclerosis, which is impaired in T2DM, includes impaired vasodilation, increased coronary artery calcification (CAC), carotid intima media thickness, arterial stiffness, and reduced arterial elasticity. Each of these alterations is represented by a marker of subclinical atherosclerosis, offering a cost-effective alternative compared to classic cardiac imaging. Their additional use on top of traditional risk assessment strengthens the predictive risk for developing coronary artery disease (CAD). We, herein, review the existing literature on the effect of glycemic control on each of these markers separately. Effective glycemic control, especially in earlier stages of the disease, attenuates progression of structural markers like intima-media thickness and CAC. Functional markers are improved after use of newer anti-diabetic agents, such as incretin-based treatments or sodium-glucose co-transporter-2 inhibitors, especially in T2DM patients with shorter disease duration. Larger prospective trials are needed to enhance causal inferences of glycemic control on clinical endpoints of CAD.

Arterial Stiffness in Type 1 Diabetes: The Case for the Arterial Wall Itself as a Target Organ

Arterial stiffness (AS) integrates the cumulative burden of known and unknown cardiovascular risk factors on the elastic wall of large arteries along the lifespan of an individual. As a marker of vascular aging, AS is an independent predictor of cardiovascular events and improves cardiovascular risk prediction when added to the Framingham Risk Score. In addition, AS may affect the microvasculature and promote the development of microvascular complications. Its impact on both the macro- and microvasculature has led to the concept that the arterial wall itself should be considered as a target organ. Here, we review the biological and clinical consequences of AS on the macro- and microvasculature and the measurement of AS in routine clinical practice. We also discuss the pathophysiological mechanisms underpinning AS development using diabetes and, in particular, type 1 diabetes, as a disease model with a high risk of cardiovascular events and microvascular complications that are accelerated by AS.

Study protocol: a prospective controlled clinical trial to assess surgical or medical treatment for paediatric type 2 diabetes (ST2OMP)

INTRODUCTION

The pathophysiology of type 2 diabetes (T2D) in youth differs from adults and conventional medical treatment approaches with lifestyle change, metformin, thiazolidinediones or insulin are inadequate. Metabolic bariatric surgery (MBS) improves multiple health outcomes in adults with T2D. Initial small, uncontrolled studies of Roux-en-Y gastric bypass have also suggested beneficial effects in adolescents. Definitive studies in youth with T2D are lacking, especially with the now more common form of MBS, vertical sleeve gastrectomy (VSG). The surgical or medical treatment for paediatric type 2 diabetes (ST₂OMP) clinical trial was designed to test the hypothesis that VSG will more effectively reduce hyperglycaemic and diabetes comorbidities than the best currently available medical treatment incorporating state of the art pharmacotherapies. ST₂OMP is also designed to better understand the pancreatic and enterohepatic mechanisms by which MBS improves diabetes and its associated comorbidities.

METHODS AND ANALYSIS

ST₂OMP is a prospective, open-label, controlled clinical trial that will recruit 90 postpubertal participants, age range 13-19.9 years, with body mass index ≥35 kg/m² or >120% of 95th percentile and youth-onset T2D. The primary outcome is the per cent of youth achieving haemoglobin A1c <6.0% at 12 months postgroup allocation (post-VSG vs postmedical group allocation). Secondary outcomes include remission of comorbidities and measures of β-cell and incretin responses at 12 and 24 months post VSG versus AMT.

ETHICS AND DISSEMINATION

The ST₂OMP protocol was approved by the Cincinnati Children's Hospital Medical Center and the University of Colorado Institutional Review Boards. Written informed consent is obtained prior to study enrolment. Study findings will be widely disseminated through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

Clinical Trials.Gov NCT04128995.

Youth-onset type 2 diabetes: translating epidemiology into clinical trials

Globally, the proportion of new diagnoses of youth-onset diabetes represented by type 2 diabetes is increasing, and youth with type 2 diabetes commonly have complications and comorbidities, as well as a higher rate of mortality. In this review, we summarise what is known about the natural progression of youth-onset type 2 diabetes from published clinical trials and large-scale prospective epidemiological studies. It is important to note that the robust pathophysiological and treatment data specifically related to individuals with a diabetes onset at ≤20 years of age largely hails from the USA. Youth-onset type 2 diabetes is characterised by pathophysiological heterogeneity and inadequate glycaemic control, highlighting the need for new treatment approaches and innovative study designs in populations of varied genetic and cultural backgrounds.

Type 2 Diabetes in Youth

The incidence of type 2 diabetes in children and adolescents in the United States rose at an annual rate of 4.8% between 2002-2003 and 2014-2015. Type 2 diabetes progresses more aggressively to complications than type 1 diabetes. For example, in one large epidemiological study, proliferative retinopathy affected 5.6% and 9.1% of children with type 1 and type 2 diabetes, respectively. Screening begins at age 10 or at onset of puberty, and is recommended among children with a BMI% ≥85 with risk factors such as a family history and belonging to a high risk racial or ethnic or racial group. HbA1C% is preferred for screening as it does not require fasting. As distinguishing between type 1 and type 2 diabetes is not straightforward, all children with new onset disease should undergo autoantibody testing. Results of lifestyle interventions for control of type 2 diabetes have been disappointing, but are still recommended for their educational value and the potential impact upon some participants. There is limited evidence for the benefit of newer mediations. Liraglutide, a GLP-1 agonist, however, has been shown to significantly reduce HbA1C% in one study and is now approved for children. Liraglutide should be considered as second line therapy.

Racial differences of early vascular aging in children and adolescents

The prevalence of non-communicable disease (NCDs) is rising globally, with a large burden recorded in sub-Saharan countries and populations of black race/ethnicity. Accelerated vascular deterioration, otherwise known as early vascular aging (EVA), is the underlying factor for highly prevalent NCDs such as hypertension. The etiology of EVA is multifactorial with a central component being arterial stiffness with subsequent development of hypertension and cardiovascular complications. Although arterial stiffness develops with increasing age, many children and adolescents are subjected to the premature development of arterial stiffness, due to genetic or epigenetic predispositions, lifestyle and behavioral risk factors, and early life programming. Race/ethnic differences in pediatric populations have also been reported with higher aortic stiffness in black (African American) compared with age-matched white (European American) counterparts independent of blood pressure, body mass index, or socioeconomic status. With known evidence of race/ethnic differences in EVA, the pathophysiological mechanisms underlying graded differences in the programming of EVA are still sparse and rarely explored. This educational review aims to address the early life determinants of EVA in children and adolescents with a particular focus on racial or ethnic differences.

Dapagliflozin decreases ambulatory central blood pressure and pulse wave velocity in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled clinical trial

OBJECTIVES

Sodium-glucose co-transporter 2 (SGLT-2) inhibitors reduce the incidence of heart failure and death in patients with type-2 diabetes mellitus. Arterial stiffness is a prominent risk factor for heart failure and overall mortality. The aim of this study was to evaluate the effects of dapagliflozin on ambulatory brachial and central blood pressure (BP) levels and arterial stiffness parameters in patients with type-2 diabetes mellitus.

METHODS

This is a double-blind, randomized, placebo-controlled clinical trial including 85 adult patients with type-2 diabetes mellitus on monotherapy or combination therapy with two of: metformin, sulphonylurea, DPP-4 inhibitor, or insulin. Patients were randomized in a 1 : 1 ratio to oral dapagliflozin 10 mg per day or placebo for 12 weeks. Study participants underwent 24-h ambulatory BP monitoring with the Mobil-O-Graph NG monitor at baseline and study-end.

RESULTS

Baseline demographic, clinical and laboratory parameters were similar in the two groups. During follow-up, 24-h brachial SBP/DBP (129.0 ± 12.6/77.3 ± 7.3 vs. 123.2 ± 12.4/75.1 ± 6.4 mmHg; P < 0.001/P = 0.008) and central SBP/DBP (117.4 ± 10.5/78.9 ± 7.3 vs. 113.3 ± 8.8/77.3 ± 6.5 mmHg; P = 0.002/P = 0.047) significantly decreased in dapagliflozin but not in the placebo group. Corresponding reductions of 24-h brachial SBP (-5.8 ± 9.5 vs. -0.1 ± 8.7, P = 0.005) and central SBP (-4.1 ± 8.0 vs. -0.7 ± 7.8; P = 0.046) were greater with dapagliflozin than placebo. Twenty-four-hour heart-rate adjusted augmentation index significantly decreased with dapagliflozin and insignificantly with placebo. Importantly, there was a significant difference in change of estimated 24-h PWV (-0.16 ± 0.32 vs. 0.02 ± 0.27; P = 0.007) favoring dapagliflozin. In generalized linear mixed models including 24-h brachial SBP as a random covariate, the adjusted marginal means of delta 24-h central SBP and delta 24-h PWV were not significantly different between-groups.

CONCLUSION

Treatment with dapagliflozin significantly reduces ambulatory brachial and central BP levels and PWV in patients with type-2 diabetes mellitus. Improvement in these parameters may substantially contribute to the cardiovascular benefits of SGLT-2 inhibitors.

Hyperglycemia and arterial stiffness across two generations

OBJECTIVE

Hyperglycemia and diabetes mellitus associate with arterial stiffness. This observational study aimed to investigate such links in two related generations from a population-based study.

METHODS

Data from 2640 participants in the ongoing Malmö Offspring Study, Sweden, was used. The participants were direct descendants, that is, parents (median age 52.5 years) and children (26.9 years). In linear regressions, arterial stiffness measured through carotid--femoral pulse wave velocity was associated with markers of glucose metabolism (fasting glucose, glycated hemoglobin, skin autoflourescence of Advanced Glycation End products), adjusted for age, sex, smoking, BMI, lipids, SBP and antihypertensive medication. Analysis was first performed in all participants and then separately in each generation. T-tests with diabetes mellitus as the grouping variable were performed for all participants and per generation.

RESULTS

In all participants, pulse wave velocity was significantly associated with glucose (β = 0.007, P = 0.018) and hemoglobin (β = 0.017, P < 0.001), but not with autoflourescence. Stratified by generation, arterial stiffness was associated with glucose (β = 0.013, P = 0.008) and glycated hemoglobin (β = 0.022, P < 0.001) only in parents. Mean pulse speed differed between participants with and without diabetes in the total group (mean difference 1.7 m/s, P < 0.001), as well as within each generation (parents: 1.3 m/s; P < 0.001, and children: 0.7 m/s; P = 0.040).

CONCLUSION

Impaired glucose metabolism and arterial stiffness were significantly associated only in the parental generation, indicating the influence of hyperglycemia on vascular aging. However, carotid--femoral pulse wave velocity differed significantly between participants with or without diabetes mellitus in both generations, suggesting that diabetes might negatively affect arterial stiffness also at a younger age.

Cardiovascular risk and heart rate variability in young adults with type 2 diabetes and arterial stiffness: The SEARCH for Diabetes in Youth Study

AIMS

To evaluate cardiovascular risk factors and heart rate variability (HRV) in young adults with type 2 diabetes and arterial stiffness and to explore the relationship between HRV and arterial stiffness.

METHODS

We studied 185 young adults with youth-onset T2D enrolled in the SEARCH for Diabetes in Youth Study. Cardiovascular risk factors and HRV were compared between individuals with and without type 2 diabetes and arterial stiffness (defined as a pulse wave velocity greater than the 90th percentile of healthy controls, >6.767 m/s). Semiparametric regression evaluated the independent relationship between HRV and PWV.

RESULTS

Participants with T2D and arterial stiffness were more likely to be older, non-Hispanic Black, have higher systolic and diastolic blood pressure, greater adiposity and obesity-related dyslipidemia (higher triglycerides and lower HDLC). Participants with T2D and arterial stiffness also had lower overall HRV (lower SDNN) with parasympathetic loss (lower RMSSD and PNN50), p < 0.05. Lower HRV tended to be but was not significantly associated with arterial stiffness after adjustment for age, race/ethnicity, sex and cardiovascular risk factors (beta coefficient = -1.11, p = 0.08).

CONCLUSIONS

Youth with T2D and arterial stiffness have a worse cardiovascular risk profile, specifically risk factors related to the metabolic syndrome and lower HRV.

Mechanistic Causes of Reduced Cardiorespiratory Fitness in Type 2 Diabetes

Type 2 diabetes (T2D) has been rising in prevalence in the United States and worldwide over the past few decades and contributes to significant morbidity and premature mortality, primarily due to cardiovascular disease (CVD). Cardiorespiratory fitness (CRF) is a modifiable cardiovascular (CV) risk factor in the general population and in people with T2D. Young people and adults with T2D have reduced CRF when compared with their peers without T2D who are similarly active and of similar body mass index. Furthermore, the impairment in CRF conferred by T2D is greater in women than in men. Various factors may contribute to this abnormality in people with T2D, including insulin resistance and mitochondrial, vascular, and cardiac dysfunction. As proof of concept that understanding the mediators of impaired CRF in T2D can inform intervention, we previously demonstrated that an insulin sensitizer improved CRF in adults with T2D. This review focuses on how contributing factors influence CRF and why they may be compromised in T2D. Functional exercise capacity is a measure of interrelated systems biology; as such, the contribution of derangement in each of these factors to T2D-mediated impairment in CRF is complex and varied. Therefore, successful approaches to improve CRF in T2D should be multifaceted and individually designed. The current status of this research and future directions are outlined.

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.

Metabolic outcomes of surgery in youth with type 2 diabetes

Youth-onset type 2 diabetes (T2D) is a formidable threat to the health of obese adolescents because of its potential for early-onset and aggressive co-morbidities and complications. The physiology of youth-onset T2D differs from T2D in adults and is associated with a greater degree of insulin resistance, a more rapid decline in pancreatic β-cell function, and a poorer response to medications. Medical management in youth is focused on combining lifestyle intervention and pharmacological treatment, but these therapies have yet to demonstrate improvements in disease progression. Metabolic bariatric surgery (MBS) is now recommended for the treatment of T2D in adults largely because of the beneficial effects on weight, ability to improve glycemic control, and, in a large proportion of people, induce diabetes remission. MBS is now being performed in adolescents with severe obesity and T2D, with initial results also showing high rates of T2D remission. Here, we review the state of medical management of youth-onset T2D and the outcomes of MBS studies in youth with T2D published to date.

Heart Rate Variability and Cardiac Autonomic Dysfunction: Prevalence, Risk Factors, and Relationship to Arterial Stiffness in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) Study

OBJECTIVE

To determine whether prior type 2 diabetes (T2D) treatment or glycemic control over time are independently associated with heart rate variability (HRV) and whether the presence of cardiac autonomic dysfunction is associated with arterial stiffness in young adults with youth-onset T2D enrolled in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study.

RESEARCH DESIGN AND METHODS

Heartbeats over 10 min were measured to derive the normal R-Rs (NN intervals). Outcomes included the standard deviation of the NN intervals (SDNN), the root mean square differences of successive NN intervals (RMSSD), percent of NN beats that differ by more than 50 ms (PNN50), and the low-frequency (LF) power domain, high-frequency (HF) power domain, and their ratio (LF:HF). Autonomic dysfunction was defined as ≥3 of 5 abnormal HRV indices compared with obese controls from a separate study.

RESULTS

A total of 397 TODAY participants were evaluated 7 years after randomization. TODAY participants had reduced HRV (SDNN 58.1 ± 29.6 ms vs. controls 67.1 ± 25.4 ms; P < 0.0001) with parasympathetic loss (RMSSD 53.2 ± 36.7 ms vs. controls 67.9 ± 35.2 ms; P < 0.0001) with sympathetic overdrive (LF:HF ratio 1.4 ± 1.7 vs. controls 1.0 ± 1.1; P < 0.0001). Cardiac autonomic dysfunction was present in 8% of TODAY participants, and these participants had greater pulse wave velocity compared with those without dysfunction (P = 0.0001). HRV did not differ by randomized treatment, but higher hemoglobin A1c (HbA_1c) over time was independently associated with lower SDNN and RMSSD and higher LF:HF ratio after adjustment for age, race-ethnicity, sex, and BMI.

CONCLUSIONS

Young adults with youth-onset T2D show evidence of cardiac autonomic dysfunction with both parasympathetic and sympathetic impairments that are associated with higher HbA_1c.

Progress in understanding youth-onset type 2 diabetes in the United States: recent lessons from clinical trials

BACKGROUND

Due to the dramatic increase in the rates of childhood obesity and youth-onset type 2 diabetes (T2D) in the late 1990s in the United States, the US government, through the National Institute of Diabetes, Digestive Disease, and Kidney (NIDDK) and the Centers for Disease Control, funded a series of large studies and trials which, together, have formed the basis for much of what we currently understand about youth-onset T2D.

DATA SOURCES

The review focus on the recent results and implications of the treatment options for Type 2 Diabetes in Adolescents and Youth (TODAY) study and the Restoring Insulin Secretion (RISE) study.

RESULTS AND CONCLUSIONS

Both TODAY and RISE studies have provided critical insight into the unique aspects of the pathophysiology of youth-onset type 2 diabetes and also provided the evidence base for our current approach to the management of this disorder.