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

Endothelial Dysfunction in Youth-Onset Type 2 Diabetes: A Clinical Translational Study

BACKGROUND

Youth-onset type 2 diabetes (Y-T2D) is associated with increased risk for coronary atherosclerotic disease, but the timing of the earliest pathological features and evidence of cardiac endothelial dysfunction have not been evaluated in this population. Endothelial function magnetic resonance imaging may detect early and direct endothelial dysfunction in the absence of classical risk factors (severe hyperglycemia, hypertension, and hyperlipidemia). Using endothelial function magnetic resonance imaging, we evaluated peripheral and coronary artery structure and endothelial function in young adults with Y-T2D diagnosed ≤5 years compared with age-matched healthy peers. We isolated and characterized plasma-derived small extracellular vesicles and evaluated their effects on inflammatory and signaling biomarkers in healthy human coronary artery endothelial cells to validate the imaging findings.

METHODS

Right coronary wall thickness, coronary artery flow-mediated dilation, and brachial artery flow-mediated dilation were measured at baseline and during isometric handgrip exercise using a 3.0T magnetic resonance imaging. Human coronary artery endothelial cells were treated with Y-T2D plasma-derived small extracellular vesicles. Protein expression was measured by Western blot analysis, oxidative stress was measured using the redox-sensitive probe dihydroethidium, and nitric oxide levels were measured by 4-amino-5-methylamino-2',7'-difluororescein diacetate.

RESULTS

Y-T2D (n=20) had higher hemoglobin A1c and high-sensitivity C-reactive protein, but similar total and LDL (low-density lipoprotein)-cholesterol compared with healthy peers (n=16). Y-T2D had greater coronary wall thickness (1.33±0.13 versus 1.22±0.13 mm; P=0.04) and impaired endothelial function: lower coronary artery flow-mediated dilation (-3.1±15.5 versus 15.9±17.3%; P<0.01) and brachial artery flow-mediated dilation (6.7±14.7 versus 26.4±15.2%; P=0.001). Y-T2D plasma-derived small extracellular vesicles reduced phosphorylated endothelial nitric oxide synthase expression and nitric oxide levels, increased reactive oxygen species production, and elevated ICAM (intercellular adhesion molecule)-mediated inflammatory pathways in human coronary artery endothelial cells.

CONCLUSIONS

Coronary and brachial endothelial dysfunction was evident in Y-T2D who were within 5 years of diagnosis and did not have severe hyperglycemia or dyslipidemia. Plasma-derived small extracellular vesicles induced markers of endothelial dysfunction, which corroborated accelerated subclinical coronary atherosclerosis as an early feature in Y-T2D.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02830308 and NCT01399385.

Major adverse events in youth-onset type 1 and type 2 diabetes: The SEARCH and TODAY studies

AIMS

To determine contemporary incidence rates and risk factors for major adverse events in youth-onset T1D and T2D.

METHODS

Participant interviews were conducted once during in-person visits from 2018 to 2019 in SEARCH (T1D: N = 564; T2D: N = 149) and semi-annually from 2014 to 2020 in TODAY (T2D: N = 495). Outcomes were adjudicated using harmonized, predetermined, standardized criteria.

RESULTS

Incidence rates (events per 10,000 person-years) among T1D participants were: 10.9 ophthalmologic; 0 kidney; 11.1 nerve, 3.1 cardiac; 3.1 peripheral vascular; 1.6 cerebrovascular; and 15.6 gastrointestinal events. Among T2D participants, rates were: 40.0 ophthalmologic; 6.2 kidney; 21.2 nerve; 21.2 cardiac; 10.0 peripheral vascular; 5.0 cerebrovascular and 42.8 gastrointestinal events. Despite similar mean diabetes duration, complications were higher in youth with T2D than T1D: 2.5-fold higher for microvascular, 4.0-fold higher for macrovascular, and 2.7-fold higher for gastrointestinal disease. Univariate logistic regression analyses in T1D associated age at diagnosis, female sex, HbA1c and mean arterial pressure (MAP) with microvascular events. In youth-onset T2D, composite microvascular events associated positively with MAP and negatively with BMI, however composite macrovascular events associated solely with MAP.

CONCLUSIONS

In youth-onset diabetes, end-organ events were infrequent but did occur before 15 years diabetes duration. Rates were higher and had different risk factors in T2D versus T1D.

Antihypertensive and Lipid-Lowering Medication Adherence in Young Adults With Youth-Onset Type 2 Diabetes

Importance

Youth-onset type 2 diabetes is associated with early development of chronic complications. Treatment of elevated blood pressure (BP), nephropathy, and dyslipidemia are critical to reduce morbidity. Data are needed on adherence to BP- and lipid-lowering medications in young adults with youth-onset diabetes.

Objective

To assess adherence and factors associated with adherence to BP- and lipid-lowering medications in young adults with youth-onset type 2 diabetes and diagnoses of hypertension, nephropathy, or dyslipidemia.

Design, Setting, and Participants

This cohort study measured medication adherence with 3 monthly unannounced pill counts at 2 time points 1 year apart during iCount, conducted during the last years (2017-2019) of the observational phase of the Treatment Options for Type 2 Diabetes in Adolescents and Youth study. Psychosocial factors associated with medication adherence were examined. Participants included individuals with youth-onset type 2 diabetes with hypertension, nephropathy, or dyslipidemia receiving diabetes care in their communities. Data were analyzed from September 2022 to September 2023.

Main Outcomes and Measures

The main outcome was BP- and lipid-lowering medication adherence, with low adherence defined as using less than 80% of pills and high adherence, at least 80% of pills. Psychosocial factors were measured using the Beliefs about Medicines Questionnaire and Material Needs Insecurities Survey.

Results

Of 381 participants in iCount, 243 participants (mean [SD] age, 26.12 [2.51] years; 159 [65.43%] women) with hypertension, nephropathy, or dyslipidemia were included in analysis. Among 196 participants with hypertension or nephropathy, 157 (80.1%) had low adherence. Participants with low adherence, compared with those with high adherence, were younger (mean [SD] age, 25.99 [2.41] vs 27.26 [2.41] years; P = .005), had higher glycated hemoglobin A1c (mean [SD], 10.33% [2.66 percentage points] vs 8.85% [2.39 percentage points]; P = .001), shorter diabetes duration (mean [SD], 12.32 [1.49] vs 12.90 [1.46] years; P = .03), and less education (eg, 17 participants [10.83%] vs 0 participants with no high school diploma; P = .004). Of 146 participants with dyslipidemia, 137 (93.8%) had low adherence and only 9 participants (6.2%) had high adherence. Of 103 participants with low adherence to BP-lowering medications and using oral hypoglycemic agents, 83 (80.58%) had low adherence to oral hypoglycemic agents. Beliefs that medications are necessary were higher for participants with high adherence to BP-lowering medications than those with low adherence in unadjusted analyses (mean [SD] necessity score, 16.87 [6.78] vs 13.89 [9.15]; P = .03). In adjusted multivariable analyses of participants with hypertension or nephropathy, having at least 1 unmet social need (odds ratio [OR], 0.20; 95% CI, 0.05-0.65; P = .04) and medication concerns (OR, 0.63; 95% CI, 0.40-0.96; P = .01) were associated with worse medication adherence 1 year follow-up. Diabetes distress, self-efficacy, depressive and anxiety symptoms, and self-management support were not associated with 1-year medication adherence.

Conclusions and Relevance

These findings suggest that adherence to BP- and lipid-lowering medications was very poor in this cohort. To improve medication adherence and prevent early vascular events, approaches that identify and address medication concerns and unmet social needs are needed.

Childhood Obesity and Cardiovascular Disease Risk

PURPOSE OF REVIEW

The global epidemic of youth-onset obesity is tightly linked to the rising burden of cardiometabolic disease across the lifespan. While the link between childhood obesity and cardiovascular disease is established, this contemporary review summarizes recent and novel advances in this field that elucidate the mechanisms and impact of this public health issue.

RECENT FINDINGS

The review highlights the emerging data supporting the relationship between childhood adverse events, social determinants of health, and systemic and institutional systems as etiological factors. We also provide updates on new screening and treatment approaches including updated nutrition and dietary guidelines and benchmarks for pediatric obesity screening, novel pharmacological agents for pediatric obesity and type 2 diabetes such as glucagon-like 1 peptide receptor agonists, and we discuss the long-term safety and efficacy data on surgical management of pediatric obesity. The global burden of pediatric obesity continues to rise and is associated with accelerated and early vascular aging especially in youth with obesity and type 2 diabetes. Socio-ecological determinants of risk mediate and moderate the relationship of childhood obesity with cardiometabolic disease. Recognizing the importance of neighborhood level influences as etiological factors in the development of cardiovascular disease is critical for designing effective policies and interventions. Novel surgical and pharmacological interventions are effective pediatric weight-loss interventions, but future research is needed to assess whether these agents, within a socio-ecological framework, will be associated with abatement of the pediatric obesity epidemic and related increased cardiovascular disease risk.

Can Surrogate Markers Help Define Cardiovascular Disease in Youth?

PURPOSE OF REVIEW

Non-invasive measurements such as arterial stiffness serve as proxy surrogates for detection of early atherosclerosis and ASCVD risk stratification. These surrogate measurements are influenced by age, gender, and ethnicity and affected by the physiological changes of puberty and somatic growth in children and adolescents.

RECENT FINDINGS

There is no consensus of the ideal method to measure surrogate markers in youth (< 18 years of age), nor standardized imaging protocols for youth. Currently, pediatric normative data are available but not generalizable. In this review, we provide rationale on how currently used surrogates can help identify subclinical atherosclerosis in youth and affirm their role in identifying youth at risk for premature CVD.

Cumulative insulin resistance and hyperglycemia with arterial stiffness and carotid IMT progression in 1,779 adolescents: a 9-yr longitudinal cohort study

In pediatric population with diabetes and obesity, insulin resistance (HOMA-IR) has been associated with worsening vascular outcomes, however, the cumulative role of HOMA-IR, hyperglycemia, and hyperinsulinemia on repeatedly measured vascular outcomes in asymptomatic youth is unknown. We examined the longitudinal associations of fasting glucose, insulin, and HOMA-IR with carotid-femoral pulse wave velocity (cfPWV) and carotid intima-media thickness (cIMT). From the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort, UK 1,779, 15-yr-old participants were followed up for 9 yr. Glucose, insulin, and HOMA-IR assessed at 15, 17, and 24 yr and sex-specifically dichotomized as ≥75th percentile, indicating high category and <75th percentile as reference. cfPWV and cIMT were measured at ages 17 and 24 yr. Associations were examined using linear mixed-effect models adjusted for cardiometabolic and lifestyle covariates. Among 1,779 participants [49.9% female], glucose, insulin, and HOMA-IR had a J- or U-shaped increase from ages 15 through 24 yr. The cumulative exposures to hyperinsulinemia effect estimate -0.019 mU/L; [95% CI -0.019 to -0.002; P = 0.033] and high HOMA-IR: -0.021; [-0.039 to -0.004; P = 0.019] from 15 to 24 yr of age were negatively associated with the 7-yr cfPWV progression. Only cumulative hyperinsulinemia and high HOMA-IR from ages 15 to 17 yr but not from ages 17 to 24 yr was associated with decreased cfPWV progression. There were no associations between cumulative hyperglycemia and cfPWV or cIMT progression. Hyperinsulinemia and HOMA-IR were not associated with cIMT progression. In conclusion, late adolescence may be an optimal timing for intervention targeted at sustaining the protective effect of the decline of insulin and insulin resistance on arterial stiffness progression.NEW & NOTEWORTHY Fasting plasma glucose, insulin, and insulin resistance had a J- or U-shaped increase from 15 to 24 yr with the base of the curve at age 17 yr. Cumulative high insulin and high insulin resistance from 15 to 24 yr were negatively associated with arterial stiffness progression from ages 17 to 24 yr. Age 17 yr may be an optimal timing for intervention targeted at sustaining the protective effect of the decline of insulin and insulin resistance on arterial stiffness progression.

Handgrip strength is inversely associated with augmentation index in patients with type 2 diabetes

Handgrip strength (HGS) is a measure of overall skeletal muscle strength and is used to identify risks for cardiovascular disease and mortality. Furthermore, HGS is an indicator of arterial stiffness that leads to atherosclerotic cardiovascular disease. This study aimed to examine the relationship between HGS and augmentation index (AIx) in patients with type 2 diabetes. A cross-sectional study was conducted to examine patients with type 2 diabetes whose HGS and AIx were measured in our hospital. AIx was measured noninvasively using an applanation tonometer, and multiple regression analyses were conducted to assess the independent relationship between HGS and AIx. This study included 404 patients. After adjusting for age, gender, body mass index, duration of diabetes, smoking and exercise habit, biochemical parameters, and physiological parameters related to arterial stiffness, HGS was found to be independently and inversely associated with AIx (β = - 0.270, p = 0.006). HGS was independently and inversely associated with AIx in patients with type 2 diabetes. Patients with diminished HGS should be subjected to intensive exercise therapy for reducing the risk of arterial stiffness and cardiovascular disease.Trial registration: UMIN000023010.

Incidence of long-term diabetes complications and mortality in youth-onset type 2 diabetes: A systematic review

AIMS

This systematic review aims to assess the incidence of chronic kidney disease (CKD), cardiovascular disease (CVD) and mortality in people with type 2 diabetes diagnosed <20 years.

METHODS

We searched MEDLINE, Embase and Cochrane Library for longitudinal studies published between 1 January 2000 and 31 November 2021.

RESULTS

Seventeen studies (15 reporting CKD, 3 reporting CVD, 5 reporting mortality) from seven countries of sample size ranging between 96 and 4,141 were eligible. Most studies were conducted in North America and Europe (n = 14). Diabetes duration at enrolment varied from 0 to 8.3 years and follow-up duration from 1 to 12.6 years. The incidence rates (per 1,000 person-year) of albuminuria ranged between 12.4 and 114.8, macroalbuminuria or proteinuria between 10 and 35.0, end-stage kidney disease (ESKD) between 0.4 and 25.0, CVD between 3.7 and 19.5, and mortality between 1.0 and 18.6. The highest incidence rates of albuminuria, ESKD and mortality were recorded in Australian Aboriginal and Pima Indian populations. Youth-onset type 2 diabetes was associated with greater risk of developing CKD compared with type 1 diabetes in most studies.

CONCLUSION

Studies reporting CVD in youth-onset type 2 diabetes are scarce. Estimated incidence rates of CKD and mortality in youth-onset type 2 diabetes varied across different study populations, potentially higher in indigenous people. Youth with type 2 diabetes are at higher risk of adverse kidney outcomes than their type 1 counterparts. More studies are needed in regions outside of North America and Europe.

Diabetes Affects the Relationship between Heart Rate Variability and Arterial Stiffness in a Gender-Specific Manner

Background and Aims: Heart rate variability (HRV), i.e., the beat-by-beat fluctuations in heart rate (HR) reflecting the autonomic nervous system balance, is altered in patients with diabetes. This has been associated with arterial aging (stiffer arteries) and differs in men and women. The present study hypothesized that the impact of HRV on arterial aging, indexed as carotid–femoral pulse wave velocity (PWV), differs in a gender-specific manner and is affected by diabetes mellitus. Method: A total of 422 outpatients (187 women and 235 men) were studied. PWV was measured using the validated SphygmoCor device (AtCor Medical). Time-domain and frequency-domain parameters were measured to assess HRV. Results: The prevalence of diabetes was 30.8% with a slight, but nonsignificant, greater prevalence in men. Both age and SBP were independent determinants of PWV in each of the four groups (men and women with or without diabetes). Low-frequency activity was inversely correlated with PWV. It was greater in women without diabetes, but it was not significant in men regardless of the presence of diabetes. Conclusions: Beyond age, blood pressure, and diabetes, impaired cardiac autonomic function assessed by determination of HRV was significantly associated with arterial aging. The association between lower sympathetic and parasympathetic activity and stiffer arteries was significant in women, but not in men.

Uric acid and arterial stiffness in children and adolescents: Role of insulin resistance and blood pressure

Several studies describe the association between serum uric acid (SUA) and arterial stiffness in adults. Uric acid contributes through several mechanisms to the increase in blood pressure (BP) and adversely affects the insulin signaling pathway. Moreover, SUA predict the development of hypertension and insulin resistance up to type 2 diabetes. Early arterial stiffening, estimated by carotid-femoral pulse wave velocity (PWV), may already be present in pediatric age. Aim of our study was to investigate the relationship between SUA and PWV in a pediatric population and its interaction with insulin resistance and BP. In 322 children and adolescents (56.2% male, mean age 11.3 [SD 2.8] years), we measured weight, height, waist circumference, BP and PWV. We also assayed SUA and estimated glomerular filtration rate (eGFR) and calculated HOMA-index as a marker of insulin resistance. Simple and multiple regression analyses were performed to assess variables associated with PWV. Mediation models were applied to identify the direct and indirect effects of individual variables on PWV. On univariate analysis, age (p < 0.001), waist circumference-to-height ratio (p = 0.036), systolic and diastolic BP (SBP and DBP) z-score (p < 0.001), heart rate (p = 0.028), SUA (p = 0.002), HOMA-index (p < 0.001), and eGFR (p = 0.014) were significantly associated with PWV. The multiple regression model showed that only age (p = 0.028), SBP z-score (p = 0.006), and heart rate (p = 0.001) were significantly associated with PWV. The results were superimposable when the DBP z-score replaced the SBP z-score in the model. Mediation models showed that the effect of eGFR on PWV was fully mediated by SUA (p = 0.015) and that the effect of SUA on PWV was totally mediated by HOMA-index (p < 0.001). Both SUA (p < 0.01) and HOMA-index (p < 0.01) had a significant association with higher SBP (DBP) z-scores. The double mediation model including both BP and HOMA-index showed that the SUA effect on PWV was totally mediated by both variables (p = 0.005, for HOMA-index, p = 0.004, for SBP z-score and p = 0.007, for combined effect). The results were superimposable when the DBP z-score replaced the SBP z-score in the model. In conclusion, insulin resistance and BP are both important mediators of the association between SUA and vascular stiffness in pediatric age.

Arterial stiffness precedes hypertension and metabolic risks in youth: a review

Arterial stiffness is a strong predictor of cardiovascular events and all-cause mortality in middle-aged and old adults. Arterial stiffness has been limited to being an intermediate marker of atherosclerotic cardiovascular events in adolescents and young adult studies. The paucity of normative longitudinal data and repeated gold-standard assessments of arterial stiffness among the young population has occasioned a huge knowledge gap in its clinical utility. This review summarizes recent longitudinal evidence in a large adolescent population, supporting the value of arterial stiffness as a novel risk factor for hypertension, overweight/obesity and insulin resistance. Preventing or decreasing arterial stiffness during adolescence may confer cardiometabolic health benefits in later life, but further pathological and mechanistic research is needed. The review also offers suggestions for incorporating arterial stiffness measures into routine paediatric and young adult clinical practice.

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.

The Predictive Value of Serum Calcium on Heart Rate Variability and Cardiac Function in Type 2 Diabetes Patients

BACKGROUND

Cardiovascular autonomic neuropathy (CAN) is common in patients with type 2 diabetes mellitus (T2DM), mainly presented as decreased heart rate variability (HRV) which often leads to cardiac death. However, HRV measurement is not convenient in most clinics. Therefore, identifying high-risk patients for CAN in diabetes with easier measurements is crucial for the early intervention and prevention of catastrophic consequences.

METHODS

In this cross-sectional study, 675 T2DM patients with normocalcemia were selected. Of these, they were divided into two groups: normal HRV group (n = 425, 100 ms≤ SDNN ≤180 ms) vs. declined HRV group (n = 250, SDNN <100 ms). All patients' clinical data were collected and the correlation of clinical variables with HRV were analyzed by correlation and logistic regression analysis. The area below the ROC curve was used to evaluate the predictive performance of serum calcium on HRV.

RESULTS

In this study, declines in HRV were present in 37.0% of T2DM patients. Significant differences in albumin-adjusted serum calcium levels (CaA) (8.86 ± 0.27 vs. 9.13 ± 0.39 mg/dl, p <0.001) and E/A (0.78 ± 0.22 vs. 0.83 ± 0.26, p = 0.029) were observed between declined HRV and normal HRV groups. Bivariate linear correlation analysis showed that CaA and E/A were positively correlated with HRV parameters including SDNN (p < 0.001), SDNN index (p < 0.001), and Triangle index (p < 0.05). The AUC in the ROC curve for the prediction of CaA on HRV was 0.730 (95% CI (0.750-0.815), p < 0.001). The cutoff value of CaA was 8.87 mg/dl (sensitivity 0.644, specificity 0.814). The T2DM patients with CaA <8.87 mg/dl had significantly lower HRV parameters (SDNN, SDNN index, rMSSD, and triangle index) than those with CaA ≥8.87 mg/dl (p < 0.01, respectively). Multivariate logistic regression analysis showed a significantly increased risk of declined HRV in subjects with CaA level <8.87 mg/dl [OR (95% CI), 0.049 (0.024-0.099), p < 0.001].

CONCLUSIONS

Declined HRV is associated with a lower CaA level and worse cardiac function. The serum calcium level can be used for risk evaluation of declined HRV in T2DM patients even within the normocalcemic range.