Twenty years of pediatric diabetes surveillance: what do we know and why it matters

SEARCH for Diabetes in Youth (SEARCH) was initiated in 2000 as a multicenter study to address major gaps in the understanding of childhood diabetes in the United States. An active registry of youth diagnosed with diabetes at age <20 years since 2002 assessed prevalence, annual incidence, and trends by age, race/ethnicity, sex, and diabetes type. An observational cohort nested within the population-based registry was established to assess the natural history and risk factors for acute and chronic diabetes-related complications, as well as the quality of care and quality of life of children and adolescents with diabetes from diagnosis into young adulthood. SEARCH findings have contributed to a better understanding of the complex and heterogeneous nature of youth-onset diabetes. Continued surveillance of the burden and risk of type 1 and type 2 diabetes is important to track and monitor incidence and prevalence within the population. SEARCH reported evidence of early diabetes complications highlighting that continuing the long-term follow-up of youth with diabetes is necessary to further our understanding of its natural history and to develop the most appropriate approaches to primary, secondary, and tertiary prevention of diabetes and its complications. This review summarizes two decades of research and suggests avenues for further work.

The Association Between Glycemic Variability and Macronutrients in Young Children with T1D

OBJECTIVE

There is limited information regarding the potential effect macronutrients have on postprandial glycemic variability in young children with type 1 diabetes (T1D). To date, studies examining nutrition and glycemic outcomes either assess these factors at a single timepoint, or aggregate large datasets for group level analyses. This study examined how inter- and intraindividual fluctuations in carbohydrate, fat, and protein intake impact glycemic variability in the postprandial period for young children with T1D.

METHODS

Thirty-nine young children, aged 2-6 years, wore a continuous glucose monitor for 72 hr, while their parents completed detailed diet records of all food intake. The analyses tested three multilevel models to examine intra- and interindividual differences between food intake and postprandial glycemic variability.

RESULTS

The results suggest carbohydrate intake, relates to greater postprandial glycemic variability. In contrast, the results reveal the inverse effect for protein, suggesting a tendency for young children who ate more protein at some meals to have lower postprandial glycemic variability, with the exception of lunch. There was no effect for fat on postprandial glycemic variability.

CONCLUSION

These results suggest protein consumption may be an important consideration when aiming for optimal glycemic levels for some meals. When counseling parents of young children with T1D on common behaviors underlying glycemic excursion, pediatric psychologists may consider discussing the nutritional make up of children's meals. Further, the results demonstrate retaining longitudinal data at the person level, versus aggregating individual data for group level analyses, may offer new information regarding macronutrient intake and glycemic outcomes.

Trajectories in estimated glomerular filtration rate in youth-onset type 1 and type 2 diabetes: The SEARCH for Diabetes in Youth Study

AIMS

We sought to characterize the direction and associated factors of eGFR change following diagnosis of youth-onset type 1 and type 2 diabetes.

METHODS

We assessed the direction of eGFR change at two visits (mean 6.6 years apart) in SEARCH, a longitudinal cohort study of youth-onset type 1 and type 2 diabetes. We used the CKiDCr-CysC equation to estimate GFR and categorized 'rising' and 'declining' eGFR as an annual change of ≥3 ml/min/1.73 m2 in either direction. Multivariable logistic regression evaluated factors associated with directional change in eGFR.

RESULTS

Estimated GFR declined in 23.8% and rose in 2.8% of participants with type 1 diabetes (N = 1225; baseline age 11.4 years), and declined in 18.1% and rose in 15.6% of participants with type 2 diabetes (N = 160; baseline age 15.0 years). Factors associated with rising and declining eGFR (versus stable) in both type 1 and type 2 diabetes included sex, age at diagnosis, baseline eGFR and difference in fasting glucose between study visits. Additional factors in type 1 diabetes included time from baseline visit, HbA1c and body mass index.

CONCLUSIONS

Over the first decade of diabetes, eGFR decline is more common in type 1 diabetes whereas eGFR rise is more common in type 2 diabetes.

Diabetic ketoacidosis at diagnosis among youth with type 1 and type 2 diabetes: Results from SEARCH (United States) and YDR (India) registries

BACKGROUND

There is significant global variation in the prevalence of diabetic ketoacidosis (DKA) at diagnosis among youth with type 1 diabetes (T1D). However, data for youth with type 2 diabetes (T2D) are limited, even in developed countries. We compared the prevalence of DKA at diagnosis among individuals with T1D and T2D from the SEARCH for Diabetes in Youth (SEARCH) and the Registry of Youth Onset Diabetes in India (YDR) registries.

METHODS

We harmonized the SEARCH and YDR registries to the structure and terminology in the Observational Medical Outcome Partnership Common Data Model. Data used were from youth with T1D and T2D diagnosed before 20 years and newly diagnosed between 2006 and 2012 in YDR and 2009 and 2012 in SEARCH.

RESULTS

There were 5366 US youth (4078 with T1D, 1288 with T2D) and 2335 Indian youth (2108 with T1D, 227 with T2D). More than one third of T1D youth enrolled in SEARCH had DKA at diagnosis which was significantly higher than in YDR (35.3% vs 28.7%, P < .0001). The burden of DKA in youth with T1D was significantly higher among younger age groups; this relationship was similar across registries (P = .4). The prevalence of DKA among T2D in SEARCH and YDR were 5.5% and 6.6% respectively (P = .4).

CONCLUSIONS

There is significant burden of DKA at diagnosis with T1D among youth from United States and India, especially among the younger age groups. The reasons for this high prevalence are largely unknown but are critical to developing interventions to prevent DKA at diagnosis.

Obese and Type 2 Diabetic Youth Have Increased Forward and Backward Wave Reflections

OBJECTIVE

Pulse wave analysis estimates arterial wave reflections relating to left ventricular dysfunction and cardiovascular event risk in adults. Forward and backward waves (Pf and Pb) may improve risk stratification for cardiovascular events. Data in youth are lacking. We hypothesized that a significant difference in wave reflections would be identified in young subjects with adverse cardiovascular risk factors. Approach and Results: Vital signs and labs were obtained in 551 patients aged 10 to 24 years who were lean (L=199), obese (O=173), or had type 2 diabetes (T=179). Wave separation was performed. Differences in cardiovascular risk factors and wave reflections were assessed using ANOVA. General linear models were constructed to elucidate independent predictors of wave reflections. O and T subjects had an adverse cardiovascular risk profile versus L. O and T subjects had higher Pf and Pb versus L (P≤0.05). When adjusted for adiposity and other cardiovascular risk factors, reflection magnitude increased from L to O to T with higher T versus L values (P≤0.05) and near-significant O versus L values (P=0.06). Adiposity and blood pressure were major determinants of wave reflections. Pb influenced log left ventricular mass index, log E/e', and log composite carotid intima-media thickness.

CONCLUSIONS

Adolescents and young adults with obesity and type 2 diabetes have altered forward and backward wave reflections versus lean controls related to adiposity, BP, and insulin levels. These parameters may help risk stratify patients with adverse cardiovascular risk factors.

Markers of cholesterol synthesis are elevated in adolescents and young adults with type 2 diabetes

BACKGROUND

Changes in cholesterol absorption and cholesterol synthesis may promote dyslipidemia and cardiovascular disease in individuals with type 2 diabetes mellitus (T2DM).

OBJECTIVE

To assess cholesterol synthesis and absorption in lean individuals, obese individuals, and individuals with T2DM.

METHODS

We measured lathosterol and lanosterol (markers of cholesterol synthesis) as well as campesterol and β-sitosterol (markers of cholesterol absorption) in the serum of 15 to 26 years old individuals with T2DM (n = 95), as well as their lean (n = 98) and obese (n = 92) controls.

RESULTS

Individuals with T2DM showed a 51% increase in lathosterol and a 65% increase in lanosterol compared to lean controls. Similarly, obese individuals showed a 31% increase in lathosterol compared to lean controls. Lathosterol and lanosterol were positively correlated with body mass index, fasting insulin and glucose, serum triglycerides, and C-reactive protein, and negatively correlated with HDL-cholesterol. In contrast, campesterol and β-sitosterol were not altered in individuals with T2DM. Moreover, campesterol and β-sitosterol were negatively correlated with body mass index, fasting insulin, and C-reactive protein and were positively correlated with HDL-cholesterol.

CONCLUSIONS

Adolescents and young adults with T2DM show evidence of increased cholesterol synthesis compared to non-diabetic lean controls. These findings suggest that T2DM may promote cardiovascular disease by increasing cholesterol synthesis, and provide additional rationale for the use of cholesterol synthesis inhibitors in this group.

The association of low-density lipoprotein cholesterol with elevated arterial stiffness in adolescents and young adults with type 1 and type 2 diabetes: The SEARCH for Diabetes in Youth study

AIM

Our aim was to explore the relationship of Low-Density Lipoprotein Cholesterol (LDL-C) with subclinical cardiovascular disease (CVD) in youth with T1D and T2D. We hypothesized the association of LDL-C with elevated arterial stiffness (AS) would be partially accounted by the co-occurrence of other CVD factors.

METHOD

We included 1376 youth with T1D and 157 with T2D from the SEARCH study. CVD risk factors including LDL-C, waist to height ratio (WHtR), mean arterial pressure (MAP), HbA1c, albumin to creatinine ratio (ACR), and insulin sensitivity (IS) score were measured at both visits. At follow up, elevated carotid-femoral AS was defined as levels above 6.8 m/s. Multivariable logistic regression evaluated the odds of elevated AS as a function of the average CVD risk factors.

RESULTS

At follow up, age was 18.0 ± 4.1 and 21.6 ± 3.5 years and duration of diabetes was 7.8 ± 1.9 and 7.7 ± 1.9 years in T1D and T2D, respectively. Elevated AS was found in 8.4% of T1D and 49.0% of T2D participants. Each SD increase in LDL-C was associated with 1.28 increased odds (95% CI 1.05-1.54, P = .013) of elevated AS in youth with T1D. The association was similar but not statistically significant in T2D. WHtR, IS, and MAP were associated with elevated AS in both groups. Adjustment for WHtR or IS attenuated to non-significance the relationship between LDL-C and AS in T1D.

CONCLUSIONS

Obesity and insulin resistance attenuate the association of high LDL-C with AS suggesting they partially account for the adverse effects of LDL-C on cardiovascular health in youth with T1D.

Accelerated Early Vascular Aging Among Adolescents With Obesity and/or Type 2 Diabetes Mellitus

Background

The normal rate of subclinical vascular aging from adolescence to young adulthood has not been well‐characterized. We conducted a 5‐year longitudinal study among adolescents with normal‐weight, obesity, and/or type 2 diabetes mellitus to examine trajectories of early vascular aging.

Methods and Results

Adolescents (mean [SD] age 17.6 [3.5]; 35.3% male) had either normal weight (n=141), obesity (n=156), or type 2 diabetes mellitus (n=151) at baseline. Primary metrics used for early vascular aging included measures of vascular structure (carotid intima‐media thickness [cIMT]; common, internal, and bulb) and arterial stiffness (carotid‐femoral pulse wave velocity, and augmentation index). Longitudinal (5‐year) outcomes were examined using generalized estimating equations adjusting for baseline value, sex, race, and age. Compared with participants with normal weight, those with obesity had greater positive change in common cIMT (0.05 mm [0.03, 0.06]; P<0.001), bulb cIMT (0.02 mm [0.00, 0.05]; P=0.033), internal cIMT (0.03 mm [0.01, 0.05]; P<0.001), and pulse wave velocity carotid‐femoral (0.38 m/sec [0.14, 0.61]; P=0.001), and those with type 2 diabetes mellitus had greater positive change in common cIMT (0.05 mm [0.04, 0.07]; P<0.001), bulb cIMT (0.06 mm [0.04, 0.09]; P<0.001), internal cIMT (0.04 mm [0.02, 0.07]; P<0.001), augmentation index (4.67% [2.20, 7.13]; P<0.001), and pulse wave velocity carotid‐femoral (0.74 m/sec [0.46, 1.02]; P<0.001). Higher baseline systolic blood pressure was associated with greater positive change in common cIMT (0.007 mm [0.003, 0.011]; P<0.001), bulb cIMT (0.009 mm [0.002, 0.016]; P=0.01), internal cIMT (0.008 mm [0.003, 0.013]; P=0.001), and pulse wave velocity carotid‐femoral (0.066 m/sec [0.002, 0.130]; P=0.042).

Conclusions

These longitudinal data support the hypothesis that the presence of obesity, type 2 diabetes mellitus, and elevated baseline systolic blood pressure in early life accelerates the progression of risk factors key in the development of early vascular aging.

Youth sports participation and health status in early adulthood: A 12-year follow-up

Examining association between serial participation in youth organized sports (OS) and concurrent cardiometabolic risk factors, with long-term health status, will aid understanding the role of OS participation. Combining data from a prospective study and a follow-up survey, we aimed to determine association between youth OS participation and cardiometabolic risk factors with health and physical activity (PA) in young adulthood. Cardiometabolic risk factors were monitored yearly, and OS involvement through middle school, high school, and college, together with current status was recorded 12 years after the initial study began; 462 participants completed follow-up. Cardiometabolic risk factors included: body mass index (BMI), waist circumference, blood pressure, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) cholesterol and triglycerides, fasting glucose and insulin. Participants continuing OS participation from middle to high school and/or college had significantly lower BMI/BMI z-scores [24.7 vs 27.4 (p < 0.05) and 0.51 vs 0.82 (p < 0.05), respectively] and significantly higher HDL [48.7 vs 45.4 (p ≤ 0.05)] than those without OS participation after middle school. Waist circumference of females was significantly smaller in those who participated in OS from middle to high school and/or college (84.9 cm) compared to those who had no OS (92.1 cm), (p < 0.05). Participants continuing OS from middle to high school and/or college reported significantly higher follow-up PA levels than those who had no OS after middle school (p < 0.001). This study provides novel data showing serial participation in OS from middle to high school and/or college was associated with a superior cardiometabolic health profile in school and increased PA levels at 12-year follow-up.

Longitudinal association of biomarkers of pesticide exposure with cardiovascular disease risk factors in youth with diabetes

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death among individuals with diabetes, but little is known about the role of exposures to environmental chemicals such as pesticides in the early development of CVD risk in this population.

OBJECTIVES

To describe changes over time in concentrations of pesticide biomarkers among youth with diabetes in the United States and to estimate the longitudinal association between these concentrations and established risk factors for CVD.

METHODS

Pesticide biomarkers were quantified in urine and serum samples from 87 youth with diabetes participating in the multi-center SEARCH cohort study. Samples were obtained around the time of diagnosis (baseline visit, between 2006 and 2010) and, on average, 5.4 years later (follow-up visit, between 2012 and 2015). We calculated geometric mean (95% CI) pesticide biomarker concentrations. Eight CVD risk factors were measured at these two time points: body mass index (BMI) z-score, HbA1c, insulin sensitivity, fasting C-peptide (FCP), LDL cholesterol, HDL cholesterol, total cholesterol, and triglycerides. Linear regression models were used to estimate the associations between each pesticide biomarker at baseline and each CVD risk factor at follow-up, adjusting for baseline health outcome, elapsed time between baseline and follow up, sex, age, race/ethnicity, and diabetes type.

RESULTS

Participants were, on average, 14.2 years old at their baseline visit, and most were diagnosed with type 1 diabetes (57.5%). 4-nitrophenol, 3-phenoxybenzoic acid, 2,4-dichlorophenoxyacetic acid (2,4-D), 3,5,6-trichloro-2-pyridinol, 2,2-bis(4-chlorophenyl)-1,1-dichloroethene, and hexachlorobenzene were detected in a majority of participants at both time points. Participants in the highest quartile of 2,4-D and 4-nitrophenol at baseline had HbA1c levels at follow-up that were 1.05 percentage points (95% CI: -0.40, 2.51) and 1.27 percentage points (0.22, 2.75) higher, respectively, than participants in the lowest quartile of these pesticide biomarkers at baseline. These participants also had lower log FCP levels (indicating reduced beta-cell function) compared to participants in the lowest quartile at baseline: beta (95% CI) for log FCP of -0.64 (-1.17, -0.11) for 2,4-D and -0.39 (-0.96, 0.18) for 4-nitrophenol. In other words, participants in the highest quartile of 2,4-D had a 47.3% lower FCP level compared to participants in the lowest quartile, and those in the highest quartile of 4-nitrophenol had a 32.3% lower FCP level than those in the lowest quartile. Participants with trans-nonachlor concentrations in the highest quartile at baseline had HbA1c levels that were 1.45 percentage points (-0.11, 3.01) higher and log FCP levels that were -0.28 (-0.84, 0.28) lower than participants in the lowest quartile at baseline, that is to say, participants in the highest quartile of trans-nonachlor had a 24.4% lower FCP level than those in the lowest quartile. While not all of these results were statistically significant, potentially due to the small same size, clinically, there appears to be quantitative differences. No associations were observed between any pesticide biomarker at baseline with BMI z-score or insulin sensitivity at follow-up.

CONCLUSIONS

Exposure to select pesticides may be associated with impaired beta-cell function and poorer glycemic control among youth with diabetes.

Characterizing the weight-glycemia phenotypes of type 1 diabetes in youth and young adulthood

INTRODUCTION

Individuals with type 1 diabetes (T1D) present with diverse body weight status and degrees of glycemic control, which may warrant different treatment approaches. We sought to identify subgroups sharing phenotypes based on both weight and glycemia and compare characteristics across subgroups.

RESEARCH DESIGN AND METHODS

Participants with T1D in the SEARCH study cohort (n=1817, 6.0-30.4 years) were seen at a follow-up visit >5 years after diagnosis. Hierarchical agglomerative clustering was used to group participants based on five measures summarizing the joint distribution of body mass index z-score (BMIz) and hemoglobin A1c (HbA1c) which were estimated by reinforcement learning tree predictions from 28 covariates. Interpretation of cluster weight status and glycemic control was based on mean BMIz and HbA1c, respectively.

RESULTS

The sample was 49.5% female and 55.5% non-Hispanic white (NHW); mean±SD age=17.6±4.5 years, T1D duration=7.8±1.9 years, BMIz=0.61±0.94, and HbA1c=76±21 mmol/mol (9.1±1.9)%. Six weight-glycemia clusters were identified, including four normal weight, one overweight, and one subgroup with obesity. No cluster had a mean HbA1c <58 mmol/mol (7.5%). Cluster 1 (34.0%) was normal weight with the lowest HbA1c and comprised 85% NHW participants with the highest socioeconomic position, insulin pump use, dietary quality, and physical activity. Subgroups with very poor glycemic control (ie, ≥108 mmol/mol (≥12.0%); cluster 4, 4.4%, and cluster 5, 7.5%) and obesity (cluster 6, 15.4%) had a lower proportion of NHW youth, lower socioeconomic position, and reported decreased pump use and poorer health behaviors (overall p<0.01). The overweight subgroup with very poor glycemic control (cluster 5) showed the highest lipids and blood pressure (p<0.01).

CONCLUSIONS

There are distinct subgroups of youth and young adults with T1D that share weight-glycemia phenotypes. Subgroups may benefit from tailored interventions addressing differences in clinical care, health behaviors, and underlying health inequity.

Longitudinal Phenotypes of Type 1 Diabetes in Youth Based on Weight and Glycemia and Their Association With Complications

CONTEXT

Subclinical and clinical complications emerge early in type 1 diabetes (T1D) and may be associated with obesity and hyperglycemia.

OBJECTIVE

Test how longitudinal "weight-glycemia" phenotypes increase susceptibility to different patterns of early/subclinical complications among youth with T1D.

DESIGN

SEARCH for Diabetes in Youth observational study.

SETTING

Population-based cohort.

PARTICIPANTS

Youth with T1D (n = 570) diagnosed 2002 to 2006 or 2008.

MAIN OUTCOME MEASURES

Participants were clustered based on longitudinal body mass index z score and HbA1c from a baseline visit and 5+ year follow-up visit (mean diabetes duration: 1.4 ± 0.4 years and 8.2 ± 1.9 years, respectively). Logistic regression modeling tested cluster associations with seven early/subclinical diabetes complications at follow-up, adjusting for sex, race/ethnicity, age, and duration.

RESULTS

Four longitudinal weight-glycemia clusters were identified: The Referent Cluster (n = 195, 34.3%), the Hyperglycemia Only Cluster (n = 53, 9.3%), the Elevated Weight Only Cluster (n = 206, 36.1%), and the Elevated Weight With Increasing Hyperglycemia (EWH) Cluster (n = 115, 20.2%). Compared with the Referent Cluster, the Hyperglycemia Only Cluster had elevated odds of dyslipidemia [adjusted odds ratio (aOR) 2.22, 95% CI: 1.15 to 4.29], retinopathy (aOR 9.98, 95% CI: 2.49 to 40.0), and diabetic kidney disease (DKD) (aOR 4.16, 95% CI: 1.37 to 12.62). The EWH Cluster had elevated odds of hypertension (aOR 2.18, 95% CI: 1.19 to 4.00), dyslipidemia (aOR 2.36, 95% CI: 1.41 to 3.95), arterial stiffness (aOR 2.46, 95% CI: 1.09 to 5.53), retinopathy (aOR 5.11, 95% CI: 1.34 to 19.46), and DKD (aOR 3.43, 95% CI: 1.29 to 9.11).

CONCLUSIONS

Weight-glycemia phenotypes show different patterns of complications, particularly markers of subclinical macrovascular disease, even in the first decade of T1D.

Type 1 diabetes is associated with an increase in cholesterol absorption markers but a decrease in cholesterol synthesis markers in a young adult population

BACKGROUND

To optimize treatment and prevent cardiovascular disease in subjects with type 1 diabetes, it is important to determine how cholesterol metabolism changes with type 1 diabetes.

OBJECTIVE

The objective of the study was to compare plasma levels of campesterol and β-sitosterol, markers of cholesterol absorption, as well as lathosterol, a marker of cholesterol synthesis, in youth with and without type 1 diabetes.

METHODS

Serum samples were obtained from adolescent subjects with type 1 diabetes (n = 175, mean age 15.2 years, mean duration of diabetes 8.2 years) and without diabetes (n = 74, mean age 15.4 years). Campesterol, β-sitosterol, and lathosterol, were measured using targeted liquid chromatography tandem mass spectrometry, compared between groups, and correlated with the available cardiometabolic variables.

RESULTS

Campesterol and β-sitosterol levels were 30% higher in subjects with type 1 diabetes and positively correlated with hemoglobin A1c levels. In contrast, lathosterol levels were 20% lower in subjects with type 1 diabetes and positively correlated with triglycerides, body mass index, and systolic blood pressure.

CONCLUSION

Plasma markers suggest that cholesterol absorption is increased, whereas cholesterol synthesis is decreased in adolescent subjects with type 1 diabetes. Further studies to address the impact of these changes on the relative efficacy of cholesterol absorption and synthesis inhibitors in subjects with type 1 diabetes are urgently needed.

Inflammation and acute traffic-related air pollution exposures among a cohort of youth with type 1 diabetes

BACKGROUND

Evidence remains equivocal regarding the association of inflammation, a precursor to cardiovascular disease, and acute exposures to ambient air pollution from traffic-related particulate matter. Though youth with type 1 diabetes are at higher risk for cardiovascular disease, the relationship of inflammation and ambient air pollution exposures in this population has received little attention.

OBJECTIVES

Using five geographically diverse US sites from the racially- and ethnically-diverse SEARCH for Diabetes in Youth Cohort, we examined the relationship of acute exposures to PM2.5 mass, Atmospheric Dispersion Modeling System (ADMS)-Roads traffic-related PM concentrations near roadways, and elemental carbon (EC) with biomarkers of inflammation including interleukin-6 (IL-6), c-reactive protein (hs-CRP) and fibrinogen.

METHODS

Baseline questionnaires and blood were obtained at a study visit. Using a spatio-temporal modeling approach, pollutant exposures for 7 days prior to blood draw were assigned to residential addresses. Linear mixed models for each outcome and exposure were adjusted for demographic and lifestyle factors identified a priori.

RESULTS

Among the 2566 participants with complete data, fully-adjusted models showed positive associations of EC average week exposures with IL-6 and hs-CRP, and PM2.5 mass exposures on lag day 3 with IL-6 levels. Comparing the 25th and 75th percentiles of average week EC exposures resulted in 8.3% higher IL-6 (95%CI: 2.7%,14.3%) and 9.8% higher hs-CRP (95%CI: 2.4%,17.7%). We observed some evidence of effect modification for the relationships of PM2.5 mass exposures with hs-CRP by gender and with IL-6 by race/ethnicity.

CONCLUSIONS

Indicators of inflammation were associated with estimated traffic-related air pollutant exposures in this study population of youth with type 1 diabetes. Thus youth with type 1 diabetes may be at increased risk of air pollution-related inflammation. These findings and the racial/ethnic and gender differences observed deserve further exploration.

Association of metformin and statin medications with surrogate measures of cardiovascular disease in youth with type 1 diabetes: the SEARCH for diabetes in youth study

PURPOSE

Youth with type 1 diabetes mellitus (T1DM) are at risk of cardiovascular disease (CVD). We evaluated if metformin or statin use was associated with surrogate measures of improved CVD.

METHODS

We included participants from the SEARCH observational study. Participants treated with insulin plus metformin (n=42) or insulin plus statin (n=39) were matched with 84 and 78 participants, respectively, treated with insulin alone. Measures of arterial stiffness obtained were pulse wave velocity (PWV), augmentation index (AI75), and heart rate variability as standard deviation of the normal-to-normal interval (SDNN) and root mean square differences of successive NN intervals (RMSSD).

RESULTS

CVD measures were not significantly different among participants on insulin plus metformin versus those on insulin alone: PWV (5.9±1.0 m/sec vs. 5.8±1.5 m/sec, P=0.730), AI75 (1.8 [-6.0 to 8.0] vs. -2.4 [-10.7 to 3.8], P=0.157), SDNN (52.4 [36.8-71.1] m/sec vs. 51.8 [40.1-74.9] m/sec, P=0.592), and RMSSD (43.2 [29.4-67.6] vs. 47.4 [28.0-76.3], P=0.952). CVD measures were not different for statin users versus nonusers: PWV (5.7±0.8 m/sec vs. 5.9 ±1.1 m/sec, P=0.184), AI75 ( -4.0 [-9.5 to 1.7] vs. -6.7 [-11.3 to 5.7], P=0.998), SDNN (54.6 [43.5-77.2] m/sec vs. 63.1 [44.2-86.6] m/sec, P=0.369), and RMSSD (49.5 [31.2-74.8] vs. 59.2 [38.3-86.3], P=0.430).

CONCLUSION

We found no associations of statin or metformin use with surrogate measures of CVD. Future prospective pediatric clinical trials could address this issue.

Burden of Cardiovascular Risk Factors Over Time and Arterial Stiffness in Youth With Type 1 Diabetes Mellitus: The SEARCH for Diabetes in Youth Study

Background The incidence of type 1 diabetes mellitus (T1DM) in children is increasing, resulting in higher burden of cardiovascular diseases due to diabetes mellitus-related vascular dysfunction. Methods and Results We examined cardiovascular risk factors ( CVRF s) and arterial parameters in 1809 youth with T1DM. Demographics, anthropometrics, blood pressure, and laboratory data were collected at T1DM onset and 5 years later. Pulse wave velocity and augmentation index were collected with tonometry. ANOVA or chi-square tests were used to test for differences in measures of arterial parameters by CVRF . Area under the curve of CVRF s was entered in general linear models to explore determinants of accelerate vascular aging. Participants at the time of arterial measurement were 17.6±4.5 years old, 50% female, 76% non-Hispanic white, and duration of T1DM was 7.8±1.9 years. Glycemic control was poor (glycated hemoglobin, 9.1±1.8%). All arterial parameters were higher in participants with glycated hemoglobin ≥9% and pulse wave velocity was higher with lower insulin sensitivity or longer duration of diabetes mellitus. Differences in arterial parameters were found by sex, age, and presence of obesity, hypertension, or dyslipidemia. In multivariable models, higher glycated hemoglobin, lower insulin sensitivity, body mass index, blood pressure, and lipid areas under the curve were associated with accelerated vascular aging. Conclusions In young people with T1DM, persistent poor glycemic control and higher levels of traditional CVRF s are independently associated with arterial aging. Improving glycemic control and interventions to lower CVRF s may prevent future cardiovascular events in young individuals with T1DM.

Youth-Onset Type 2 Diabetes and the Developing Brain

PURPOSE OF REVIEW

This review describes the literature evaluating the potential adverse effects of youth-onset type 2 diabetes on the developing brain. A summary of recently published articles and the current state of knowledge are covered succinctly in this manuscript.

RECENT FINDINGS

Current literature suggests both cognitive and brain structural differences are found in youth with type 2 diabetes. Studies have shown poorer scores in a number of neurocognitive domains, particularly in areas of executive functioning and memory. Additionally, imaging studies have found differences in brain gray matter volume, white matter volume, and microstructural integrity. These findings are largely consistent with the adult literature. Youth with type 2 diabetes demonstrate lower cognitive scores and structural brain differences. Although causality has not yet been established, these findings are important because these individuals are still undergoing neurodevelopmental maturation.

Co-occurrence of early diabetes-related complications in adolescents and young adults with type 1 diabetes: an observational cohort study

BACKGROUND

One in three adolescents and young adults with type 1 diabetes have at least one early diabetes-related complication or comorbidity. We aimed to examine the prevalence and pattern of co-occurring complications in this population, as well as the related risk factors.

METHODS

This observational cohort study includes data from individuals diagnosed with type 1 diabetes before age 20 years who participated in the SEARCH for Diabetes in Youth Study across five sites in the USA. We assessed sociodemographic and metabolic risk factors at baseline and at follow-up, and diabetes complications at follow-up. A frequency analysis was done to examine the difference in observed versus expected prevalence (calculated using a contingency table assuming independence across cells) of co-occurring complications or comorbidities. A cluster analysis was done to identify unique clusters of participants based on demographic characteristics and metabolic risk factors.

FINDINGS

1327 participants who completed the follow-up visit were included in the frequency analysis. The mean age was 10·1 (SD 3·9) years at the time of type 1 diabetes diagnosis and 18·0 (4·1) years at follow-up. At a mean diabetes duration of 7·8 [SD 1·9] years, co-occurrence of any two or more complications was observed in 78 (5·9%) participants, more frequently than expected by chance alone (58 [4·4%], p=0·015). Specifically, the complications that co-occurred more frequently than expected were retinopathy and diabetic kidney disease (11 [0·8%] vs three [0·2%]; p=0·0007), retinopathy and arterial stiffness (13 [1·0%] vs four [0·3%]; p=0·0016), and arterial stiffness and cardiovascular autonomic neuropathy (24 [1·8%] vs 13 [1·0%]; p=0·015). We identified four unique clusters characterised by progressively worsening metabolic risk factor profiles (longer duration of diabetes and higher glycated haemoglobin, non-HDL cholesterol, and waist-to-height ratio). The prevalence of at least two complications increased across the clusters (six [2·3%] of 261 in the low-risk cluster, 32 [6·3%] of 509 in the moderate-risk cluster, 28 [8%] of 348 in the high-risk cluster, and five [20·8%] of 24 in the highest-risk cluster). Compared with the low-risk and moderate-risk clusters, the high-risk and highest-risk clusters were characterised by a lower proportion of participants who were non-Hispanic white, and a higher proportion of participants who had a household income below US$50 000 and did not have private health insurance.

INTERPRETATION

Early complications co-occur in adolescents and young adults with type 1 diabetes more frequently than expected. Identification of individuals with adverse risk factors could enable targeted behavioural or medical interventions that reduce the likelihood of early development of lifelong diabetes-related morbidity.

FUNDING

US Centers for Disease Control and Prevention, US National Institutes of Health.

Inflammation, adiposity, and progression of arterial stiffness in adolescents with type 1 diabetes: The SEARCH CVD Study

AIMS

We examined the association between inflammation and progression of arterial stiffness in a population of youth with type 1 diabetes (T1D).

METHODS

A total of 287 youth with T1D (median age 13 years) from SEARCH CVD, an ancillary study to the SEARCH for Diabetes in Youth, were included. Markers of inflammation (CRP, IL-6, fibrinogen, leptin, and adiponectin) and measures of pulse wave velocity (PWV) of the arm (PWV-R), trunk (PWV-T), and lower extremity (PWV-LE) were measured at baseline. Measures of PWV were repeated approximately five years later.

RESULTS

PWV-R (0.50 m/s), PWV-T (0.65 m/s), and PWV-LE (1.0 m/s) significantly increased over the follow-up (p < 0.001 for each). A significant interaction was found between waist circumference and fibrinogen (p = 0.036) on the progression of PWV-T, suggesting that fibrinogen is more strongly associated with PWV progression in lean participants.

CONCLUSIONS

Improved understanding of adiposity, inflammation, and functional changes in the vascular system in patients with T1D is crucial.

Clinical Implications of the Revised AAP Pediatric Hypertension Guidelines

BACKGROUND AND OBJECTIVES

New pediatric hypertension definitions were recently published in a clinical practice guideline (CPG). We evaluated the impact of the CPG, compared with the previous guideline ("Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents"), on the prevalence of hypertension and associations with target organ damage (TOD) in high-risk youth.

METHODS

Participants (10-18 years old) undergoing an evaluation of the cardiovascular effects of obesity and type 2 diabetes mellitus in youth were studied. Blood pressure was categorized according to the 2 guidelines as normal, elevated, and hypertension (stages 1 and 2). Measures of TOD (carotid artery intima-media thickness, pulse wave velocity, left ventricular mass, and diastolic function) were obtained. Associations between blood pressure categories and TOD and the sensitivity of hypertension classification in identifying TOD were evaluated.

RESULTS

Data were available for 364 participants (65% female sex; 15.1 ± 2.1 years of age). Hypertension was identified in 8% and 13% as defined in the Fourth Report and CPG, respectively (P = .007). The 2 guidelines revealed similar associations with TOD; however, the CPG demonstrated improved sensitivity of TOD detection in hypertensive participants. For example, the proportion of participants with an abnormal left ventricular mass categorized as hypertensive increased from 20% to 31% as defined in the Fourth Report and CPG, respectively (P < .001).

CONCLUSIONS

Incorporation of the CPG increased the prevalence of pediatric hypertension in a population of high-risk youth and improved the sensitivity of TOD identification in hypertensive participants.

Cardiovascular autonomic neuropathy in adolescents and young adults with type 1 and type 2 diabetes: The SEARCH for Diabetes in Youth Cohort Study

OBJECTIVE

To estimate the prevalence of and risk factors for cardiovascular autonomic neuropathy (CAN) in adolescents and young adults with type 1 and type 2 diabetes enrolled in the SEARCH for Diabetes in Youth Study.

METHODS

The study included 1646 subjects with type 1 diabetes (age 18 ± 4 years, diabetes duration 8 ± 2 years, HbA1c 9.1 ± 1.9%, 76% non-Hispanic Whites) and 252 with type 2 diabetes (age 22 ± 4 years, diabetes duration 8 ± 2 years, HbA1c 9.2 ± 3.0%, 45% non-Hispanic Blacks). Cross-sectional and longitudinal risk factors were assessed at baseline and follow-up visits. Area under the curve (AUC) was used to assess the longitudinal glycemic exposure and cardiovascular risk factors. CAN was assessed by time and frequency domain indices of heart rate variability (HRV). CAN was defined as the presence of ≥3 of 5 abnormal HRV indices.

RESULTS

The prevalence of CAN was 12% in adolescents and young adults with type 1 diabetes and 17% in those with type 2 diabetes. Poor long-term glycemic control (AUC HbA1c), high blood pressure, and elevated triglyceride levels were correlates of CAN in subjects with type 1 diabetes. In those with type 2 diabetes, CAN was associated with elevated triglycerides and increased urinary albumin excretion.

CONCLUSIONS

The prevalence of CAN in this multiethnic cohort of adolescents and young adults with type 1 and type 2 diabetes are comparable to those reported in adults with diabetes. Suboptimal glycemic control and elevated triglycerides were the modifiable risk factors associated with CAN.

Comparison of Surgical and Medical Therapy for Type 2 Diabetes in Severely Obese Adolescents

IMPORTANCE

Because of the substantial increase in the occurrence of type 2 diabetes in the pediatric population and the medical complications of this condition, therapies are urgently needed that will achieve better glycemic control than standard medical management.

OBJECTIVE

To compare glycemic control in cohorts of severely obese adolescents with type 2 diabetes undergoing medical and surgical interventions.

DESIGN, SETTING, AND PARTICIPANTS

A secondary analysis of data collected by the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) and Treatment Options of Type 2 Diabetes in Adolescents and Youth (TODAY) consortia was performed. Teen-LABS enrolled 242 adolescents (≤19 years of age) from March 1, 2007, through December 31, 2011. TODAY randomized 699 participants (aged 10-17 years) from July 24, 2004, through February 25, 2009. Data analysis was performed from July 6, 2015, to June 24, 2017. Anthropometric, clinical, and laboratory data from adolescents with severe obesity and type 2 diabetes who underwent treatment with metabolic or bariatric surgery in the Teen-LABS study or medical therapy in the TODAY study were compared.

INTERVENTIONS

Teen-LABS participants underwent a primary bariatric surgical procedure; TODAY participants were randomized to receive metformin therapy alone or in combination with rosiglitazone or an intensive lifestyle intervention; insulin therapy was given in cases of progression of disease.

MAIN OUTCOMES AND MEASURES

Glycemic control, body mass index, prevalence of elevated blood pressure, dyslipidemia, abnormal kidney function, and clinical adverse events were measured.

RESULTS

Data from 30 participants from Teen-LABS (mean [SD] age at baseline, 16.9 [1.3] years; 21 [70%] female; 18 [66%] white) and 63 from TODAY (mean [SD] age at baseline, 15.3 [1.3] years; 28 [44%] female; 45 [71%] white) were analyzed. During 2 years, mean hemoglobin A1c concentration decreased from 6.8% (95% CI, 6.4%-7.3%) to 5.5% (95% CI, 4.7% -6.3%) in Teen-LABS and increased from 6.4% (95% CI, 6.1%-6.7%) to 7.8% (95% CI, 7.2%-8.3%) in TODAY. Compared with baseline, the body mass index decreased by 29% (95% CI, 24%-34%) in Teen-LABS and increased by 3.7% (95% CI, 0.8%-6.7%) in TODAY. Twenty-three percent of Teen-LABS participants required a subsequent operation during the 2-year follow-up.

CONCLUSIONS AND RELEVANCE

Compared with medical therapy, surgical treatment of severely obese adolescents with type 2 diabetes was associated with better glycemic control, reduced weight, and improvement of other comorbidities. These data support the need for a well-designed, prospective controlled study to define the role of surgery for adolescents with type 2 diabetes, including health and surgical outcomes.

Impact of gestational weight gain and prepregnancy body mass index on the prevalence of large-for-gestational age infants in two cohorts of women with type 1 insulin-dependent diabetes: a cross-sectional population study

OBJECTIVES

Despite improvements in treatment modalities, large-for-gestational age (LGA) prevalence has remained between 30% and 40% among infants of mothers with type 1 insulin-dependent diabetes mellitus (TIDM). Our objective was to estimate LGA prevalence and examine the association between gestational weight gain (GWG) and prepregnancy body mass index (BMI) with LGA among mothers with TIDM.

DESIGN

Cross-sectional study.

SETTING

Regional data in Cincinnati, Ohio, from the Diabetes in Pregnancy Program Project (PPG), a prospective cohort for the period 1978-1993; national data from Consortium on Safe Labor (CSL), a multicentre cross-sectional study for the period 2002-2008.

PARTICIPANTS

The study included 333 pregnancies in the PPG and 358 pregnancies in the CSL. Pregnancies delivered prior to 23 weeks' gestation were excluded. Women with TIDM in the PPG were identified according to physician confirmation of ketoacidosis, and/or c-peptide levels, and by International Classification of Diseases, ninth version codes within the CSL. LGA was identified as birth weight >90th percentile according to gestational age, race and sex.

MAIN OUTCOME MEASURES

LGA at birth.

RESULTS

Mean±SD maternal age at delivery was 26.4±5.1 years for PPG women and 27.5±6.0 years for CSL women, p=0.008. LGA prevalence did not significantly differ between cohorts (PPG: 40.2% vs CSL: 36.6%, p=0.32). More women began pregnancy as overweight in the later cohort (PPG (16.8%) vs CSL (27.1%), p<0.001). GWG exceeding Institute of Medicine (IOM) guidelines was higher in the later CSL (56.2%) vs PPG (42.3%) cohort, p<0.001. Normal-weight women with GWG within IOM guidelines had a lower LGA prevalence in CSL (PPG: 30.6% vs CSL: 13.7%), p=0.001.

CONCLUSIONS

Normal-weight women with GWG within IOM guidelines experienced a lower LGA prevalence, supporting the importance of adherence to IOM guidelines for GWG to reduce LGA. High BMI and GWG may be hindering a reduction in LGA prevalence.