The linearized disposition index augments understanding of treatment effects in diabetes.

The disposition index, calculated by multiplying measures of insulin secretion and insulin sensitivity, is widely applied as a sensitivity-adjusted measure of insulin secretion. We have recently shown that linearizing the underlying relationship uniquely permits identification of terms relating to maximal insulin secretion capacity and the secretion-coupling relationship, with both terms separately contributing to differences in the secretion-sensitivity relationship across gradations of glycemia. Here, we demonstrate the application of this linearized equation to the evaluation of treatment-induced changes in the insulin secretion-sensitivity relationship. We applied a combination of repeated-measures multivariate linear regression (evaluating treatment-induced changes in the joint relationship of insulin sensitivity and secretion) plus mixed-model repeated measures (evaluating treatment effects on maximal secretion capacity and on the secretion-sensitivity coupling slope) and compared against a usual application of the disposition index calculated from the same measurements. This novel approach allows a more informative description of treatment-induced changes compared with the usual disposition index, including isolating the source of change within the mutually adjusted relationship and identifying treatment-induced changes in the secretion-sensitivity coupling slope and in maximal insulin secretion. Application of this linearized approach provides an expanded understanding of treatment-induced changes in the insulin sensitivity-secretion relationship.NEW & NOTEWORTHY The linearized insulin secretion-sensitivity relationship allows separate evaluation of the secretion-sensitivity slope and of maximal insulin secretion. Here, we demonstrate the application of this methodology to the evaluation of clinical trial data, showing that it provides an expanded understanding of treatment-induced changes compared with the disposition index.

Withdrawal of medications leads to worsening of OGTT parameters in youth with impaired glucose tolerance or recently-diagnosed type 2 diabetes.

BACKGROUND: The RISE Pediatric Medication Study compared strategies for preserving ß-cell function, including a 9-month follow-up after treatment withdrawal to test treatment effect durability. OBJECTIVE: Evaluate OGTT measures of glucose and ß-cell response through 12 months of intervention and 9 months of medication washout. PARTICIPANTS: Youth (n = 91) aged 10 to 19 years with BMI ≥85th percentile and impaired glucose tolerance (IGT) or recently diagnosed type 2 diabetes (T2D). METHODS: A multicenter randomized clinical trial comparing insulin glargine for 3 months followed by metformin for 9 months (G→Met) or metformin alone (Met) for 12 months. We report within-group changes from baseline to end of medication intervention (M12), baseline to 9 months post-medication withdrawal (M21), and end of medication (M12) to M21. OGTT C-peptide index [CPI] paired with 1/fasting insulin evaluated ß-cell response. RESULTS: At M12, both treatments were associated with stable fasting glucose (G→Met baseline 6.0 ± 0.1 vs M12 5.9 ± 0.2 mmol/L, P = .62; Met baseline 6.1 ± 0.2 vs M12 6.0 ± 0.2 mmol/L, P = .73) and 2-hour glucose (G→Met baseline 10.2 ± 0.4 vs M12 9.3 ± 0.5 mmol/L, P = .03; Met baseline 10.2 ± 0.4 vs M12 10.6 ± 0.6 mmol/L, P = .88). Following medication withdrawal, fasting glucose worsened (G→Met M21 8.6 ± 1.8, P = .004; Met M21 7.8 ± 0.7 mmol/L, P = .003), as did 2-hour glucose (G→Met M21 13.2 ± 1.4, P = .002; Met M21 13.1 ± 1.2 mmol/L, P = .006), associated with declines in ß-cell response. CONCLUSIONS: G→Met and Met were associated with stable glucose measures during 12 months of treatment in youth with IGT or recently diagnosed T2D. Glucose and ß-cell response worsened post-medication withdrawal, suggesting treatment must be long-term or alternative treatments pursued.

ß-cells in youth with impaired glucose tolerance or early type 2 diabetes secrete more insulin and are more responsive than in adults.

OBJECTIVE: Glycemic control deteriorates more rapidly in youth vs adults. We compared model-derived measures of ß-cell function between youth and adults with either impaired glucose tolerance (IGT) or type 2 diabetes to determine if a ß-cell defect differentiates these age groups. METHODS: This is a cross-sectional analysis of baseline data from the Restoring Insulin Secretion (RISE) Study. Youth (54 Y-IGT, 33 Y-D) and adults (250 A-IGT, 104 A-D) underwent 3-hour oral glucose tolerance tests for modeling of insulin secretion rates (ISRs), glucose sensitivity, and rate sensitivity. Insulin sensitivity was quantified as the glucose infusion rate/insulin (M/I) from a hyperglycemic clamp. RESULTS: Youth had lower insulin sensitivity despite similar body mass index. Analyses were adjusted for insulin sensitivity. Youth had higher basal ISRs (Y-IGT 200 ± 161 vs A-IGT 152 ± 74, P < .001; Y-D 245 ± 2.5 vs A-D 168 ± 115 pmol/min/m2 , P = .007) and total ISRs (Y-IGT 124 ± 86 vs A-IGT 98 ± 39, P < .001; Y-D 116 ± 110 vs A-D 97 ± 62 nmol/m2 , P = .002). Within IGT, glucose sensitivity (Y-IGT 140 ± 153 vs A-IGT 112 ± 70 pmol/min/m2 /mM, P = .004) and rate sensitivity (median[interquartile range]:Y-IGT 2271[1611, 3222] vs A-IGT 1164[685, 1565] pmol/m2 /mM, P < .001) were higher in youth, but not different by age group within diabetes. CONCLUSIONS: Model-derived measures of ß-cell function provide additional insight into the pathophysiology of type 2 diabetes in youth with higher ISRs and ß-cell secretion more responsive to glucose in youth relative to adults even after adjusting for differences in insulin sensitivity. It is unknown whether these findings in youth reflect ß-cells that are healthier or whether this is a defect that contributes to more rapid loss of function.

Integrating Diabetes Prevention Education Among Teenagers Involved in Summer Employment: Encouraging Environments for Health in Adolescence (ENHANCE).

Type 2 diabetes (T2D) in youth is a growing healthcare and public health concern. It is costly, and youth suffer from disabling and deadly comorbid conditions at a faster pace than adult onset. However, T2D is preventable. The population of obese youth at greatest risk for T2D is of minority race/ethnicity and socioeconomically disadvantaged background, which creates barriers to health promoting lifestyles. Despite being the first line of prevention efforts for T2D, efficacious behavioral lifestyle interventions are still lacking at the community level. During the summers of 2016 and 2017, a study integrated obesity and diabetes prevention health education into TeenWorks summer employment program at Indy Urban Acres in Indianapolis, Indiana. Results were analyzed using paired sample t-tests. Participants (N = 168) had a mean age of 15.8 ± 0.7 years, 61% female, 13% Hispanic, 80% Black. By the end of the intervention, physical activity (p = 0.000) and prevention knowledge (p = 0.000) were significantly higher. Dietary intake (p = 0.204), self-efficacy (p = 0.58), food insecurity (p = 0.058) and depression screening scores (p = 0.809) were not significantly different. In light of the continuing childhood obesity epidemic and increasing prevalence of prediabetes and T2D in youth, there is a pressing need to understand and reduce barriers to obesity and diabetes prevention in high-risk populations. This study demonstrated the feasibility of integrating obesity and T2D prevention health education into a teen summer employment program.

The association of sleep disturbances with glycemia and obesity in youth at risk for or with recently diagnosed type 2 diabetes.

OBJECTIVE: Poor sleep may increase obesity and type 2 diabetes (T2D) risk in youth. We explored whether subjective sleep duration, sleep quality, or risk for obstructive sleep apnea (OSA) are associated with glycemia, body mass index (BMI), or blood pressure (BP) in overweight/obese youth. METHODS: Two-hundred and fourteen overweight/obese youth of 10 to 19 years of age at risk for or recently diagnosed with T2D who were screened for the Restoring Insulin Secretion (RISE) Study had a 2-hour oral glucose tolerance test (OGTT) and completed a Cleveland Adolescent Sleepiness questionnaire and a Sleep Disturbances Scale questionnaire. Independent associations between sleep variables and measures of glycemia, BMI, and BP were evaluated with regression models. RESULTS: The multiethnic cohort was 67% female, 14.1 ± 2.1 years, and BMI 35.9 ± 6.5 kg/m2 . Habitual sleep duration <8 hours was reported in 74%. Daytime sleepiness was reported in 51%, poor sleep quality in 26%, and 30% had high obstructive sleep apnea (OSA) risk. Daytime sleepiness was associated with higher HbA1c (0.2%, P = .02) and 2-hour glucose (13.6 mg/dL, P < .05). Sleep duration, sleep quality, and OSA risk were not associated with the evaluated outcomes. Poor sleep quality and OSA risk were associated with higher BMI (2.9 kg/m2 , P = .004 and 2.83 kg/m2 , P < .003, respectively). CONCLUSIONS: In overweight/obese youth with or at risk for T2D, daytime sleepiness was associated with higher HbA1c. In addition, poor sleep quality and OSA risk were associated with higher BMI. These findings support intervention studies aimed at improving sleep quality in obese youth.

Feasibility of Implementing Community Partnerships to Provide Diabetes Prevention Services to Youth.

Type 2 diabetes (T2D) in youth has increased as a result of the obesity epidemic. Diabetes prevention programming is needed for youth, at risk for T2D, and their families. However, there is a lack of diabetes prevention services for this population. There is evidence for the benefit of lifestyle modification for decreasing diabetes risk, however there are barriers for youth to access these services in a traditional clinical setting. Our Youth Diabetes Prevention Clinic (YDPC) created partnerships within the community to increase access to diabetes prevention services for at risk youth. YDPC personnel approached community organizations who had the expertise and capacity to partner in needed areas. These partnerships allowed for the development and facilitation of a community-based diabetes prevention group. Youth and their families participated in a 12 week diabetes prevention group. We measured attendance and participant satisfaction with the program. Families attended an average of 5.1 sessions from January to October 2016. Participant satisfaction was collected five times. Physical activity was rated as "awesome" or "good" by 88% of the respondents. The nutrition activities were rated as "awesome" or "good" by 97% of respondents. Physicians and families express a desire for diabetes prevention services, however barriers make it difficult for families to fully participate. Creating partnerships within the community allows for increased access to diabetes prevention services for high-risk, underserved families.

Blood Sugar, Your Pancreas, and Unicorns: The Development of Health Education Materials for Youth With Prediabetes.

Background. The obesity epidemic has led to an increase in prediabetes in youth, causing a serious public health concern. Education on diabetes risk and initiation of lifestyle change are the primary treatment modalities. There are few existing age-appropriate health education tools to address diabetes prevention for high-risk youth. Aim. To develop an age-appropriate health education tool(s) to help youth better understand type 2 diabetes risk factors and the reversibility of risk. Method. Health education tool development took place in five phases: exploration, design, analysis, refinement, and process evaluation. Results. The project resulted in (1) booklet designed to increase knowledge of risk, (2) meme generator that mirrors the booklet graphics and allows youth to create their own meme based on their pancreas' current mood, (3) environmental posters for clinic, and (4) brief self-assessment that acts as a conversation starter for the health educators. Conclusion. Patients reported high likability and satisfaction with the health education tools, with the majority of patients giving the materials an "A" rating. The process evaluation indicated a high level of fidelity and related measures regarding how the health education tools were intended to be used and how they were actually used in the clinic setting.

Methods for Measuring Risk for Type 2 Diabetes in Youth: the Oral Glucose Tolerance Test (OGTT).

PURPOSE OF REVIEW: The oral glucose tolerance test (OGTT) is used both in clinical practice and research to assess glucose tolerance. In addition, the OGTT is utilized for surrogate measures of insulin sensitivity and the insulin response to enteral glucose and has been widely applied in the evaluation of ß-cell dysfunction in obesity, prediabetes, and type 2 diabetes. Here we review the use of the OGTT and the OGTT-derived indices for measurement of risk markers for type 2 diabetes in youth. RECENT FINDINGS: Advantages of using the OGTT for measures of diabetes risk include its accessibility and the incorporation of physiological contributions of the gut-pancreas axis in the measures of insulin response to glucose. Mathematical modeling expands the potential gains from the OGTT in physiology and clinical research. Disadvantages include individual differences in the rate of glucose absorption that modify insulin responses, imperfect control of the glycemic stimulus, and poor intraindividual reproducibility. Available research suggests the OGTT provides valuable information about the development of impaired glycemic control and ß-cell function in obese youth along the spectrum of glucose tolerance.

Review of methods for measuring ß-cell function: Design considerations from the Restoring Insulin Secretion (RISE) Consortium.

The Restoring Insulin Secretion (RISE) study was initiated to evaluate interventions to slow or reverse the progression of ß-cell failure in type 2 diabetes (T2D). To design the RISE study, we undertook an evaluation of methods for measurement of ß-cell function and changes in ß-cell function in response to interventions. In the present paper, we review approaches for measurement of ß-cell function, focusing on methodologic and feasibility considerations. Methodologic considerations included: (1) the utility of each technique for evaluating key aspects of ß-cell function (first- and second-phase insulin secretion, maximum insulin secretion, glucose sensitivity, incretin effects) and (2) tactics for incorporating a measurement of insulin sensitivity in order to adjust insulin secretion measures for insulin sensitivity appropriately. Of particular concern were the capacity to measure ß-cell function accurately in those with poor function, as is seen in established T2D, and the capacity of each method for demonstrating treatment-induced changes in ß-cell function. Feasibility considerations included: staff burden, including time and required methodological expertise; participant burden, including time and number of study visits; and ease of standardizing methods across a multicentre consortium. After this evaluation, we selected a 2-day measurement procedure, combining a 3-hour 75-g oral glucose tolerance test and a 2-stage hyperglycaemic clamp procedure, augmented with arginine.

The ENCOURAGE healthy families study: A comparative effectiveness trial to reduce risk for type 2 diabetes in mothers and children.

INTRODUCTION: Trials in adults have demonstrated that interventions targeting lifestyle are effective in preventing or delaying type 2 diabetes (T2D). To address this need in youth, we developed ENCOURAGE Healthy Families (ENCOURAGE), based on the US Diabetes Prevention Program (DPP). STUDY DESIGN: Here, we present results of the ENCOURAGE randomized, comparative effectiveness trial in which we evaluated ENCOURAGE delivered to (1) mothers only, and (2) mothers with added content delivered to their children. PARTICIPANTS: The study was performed in Indianapolis, IN, at an academic medical center and the YMCA; December 2012 to April 2016. Women with a history of gestational diabetes mellitus (GDM) or prediabetes with children aged 8 to 15 years enrolled (n = 128). OUTCOME MEASURES: Outcomes were collected at baseline, postintervention (3 months), 6 and 12 months. The primary outcome was weight change at 3 months in adults; secondary outcomes included glycosylated hemoglobin (HbA1c), lipids, and blood pressure. RESULTS: In neither program did mothers' weight change. HbA1c decreased at 3 months in both groups (mothers only=-0.09%, P = .019; mothers and children=-0.11%, P = .003). Participating children had a reduction in body mass index (BMI) percentile at 3 (-1.77, P = .014), 6 (-3.0, P = .002), and 12 months (-2.91, P = .004). HbA1c decreased in children in both groups (mothers only = -0.12% at 3 months [P < .0001], -0.13% at 6 months [P < .001], and -0.07% at 12 months [P = .001]; mothers and children = -0.08% at 3 months (P < .0001), -0.07% at 6 months (P = .0004), and -0.04% at 12 months (P = .03). CONCLUSION: ENCOURAGE was beneficial for reducing BMI percentile in participating children.

Advancing diabetes management in adolescents: Comparative effectiveness of mobile self-monitoring blood glucose technology and family-centered goal setting.

BACKGROUND: As adolescents gain autonomy, it remains important for parents to be involved with diabetes management to avoid deterioration in glycemic control. Technologies for self-monitoring of blood glucose (SMBG) allow for remote monitoring in real-time by parents. This research compared 3 strategies for improving SMBG and diabetes self-care in the short-term. These strategies were: (1) health information technology (HIT)-enhanced blood glucose meter that shared blood glucose data among patients, their parent, and care providers, and allowed for text messaging; (2) family-centered goal setting; and (3) a combination of (1) and (2). METHODS: One hundred twenty-eight participants enrolled; 97 adolescent-parent pairs attended clinic at 3-month intervals during the 6-month intervention. Differences between treatment groups were evaluated using analysis of variance (ANOVAs) for continuous variables and χ2 tests for frequencies. Within patient changes were evaluated using paired t tests. RESULTS: Participants in the HIT-enhanced SMBG group had no change in mean glycosylated hemoglobin (HbA1c). Participants assigned to family-centered goal setting had a non-significant decrease in HbA1c of -0.3% (P = .26) from baseline to 6 months. Participants in the combined approach had a significant decrease in HbA1c of -0.6% (P = .02) from baseline to 3 months, but the decrease of -0.4% at 6 months was non-significant (P = .51). The change in HbA1c from baseline to 3 months was greater for the combined approach than for the HIT-enhanced SMBG (P = .05) or family-centered goal setting (P = .01). CONCLUSIONS: Our data suggest that utilizing the family-centered goal setting strategy when implementing HIT-enhanced diabetes technology deserves further study.

Morning blood pressure is associated with sleep quality in obese adolescents.

OBJECTIVE: To examine relationships among blood pressure (BP), adiposity, and sleep quality with the use of overnight polysomnography in obese adolescents. STUDY DESIGN: Overnight polysomnogram and morning BP measurements were performed in obese (body mass index [BMI] >95th percentile) nondiabetic adolescents (eligible age range 12-18 years, n = 49). Subjects were stratified into 2 groups, one with normal BP, and one with elevated BP, and demographic and clinical characteristics were compared between the groups. Multiple linear regression analysis was used to assess the effects of sleep quality on BP. RESULTS: Participants (n = 27) had a normal morning BP, and 22 (44.9%) had elevated morning BP. There were no differences in age (P = .53), sex (P = .44), race (P = .58), or BMI (P = .56) between the 2 BP groups. The group with elevated BP spent shorter percentages of time in rapid eye movement (REM; P = .006) and slow-wave sleep (SWS; P = .024). Multiple linear regression analysis showed that a lower percentage of both REM and SWS was associated with increased morning BP after we adjusted for pubertal stage, sex, race, and BMI. CONCLUSION: Lack of deeper stages of sleep, REM sleep, and SWS is associated with greater morning BP in obese adolescents, independent of BMI. Poor sleep quality should be considered in the work-up of obese youth with hypertension. Intervention studies are needed to evaluate whether improving the quality of sleep will decrease BP elevation.

Profound defects in ß-cell function in screen-detected type 2 diabetes are not improved with glucose-lowering treatment in the Early Diabetes Intervention Program (EDIP).

BACKGROUND: Few studies have measured the ability of interventions to affect declining ß-cell function in screen-detected type 2 diabetes. The Early Diabetes Intervention Programme (ClinicalTrials.gov NCT01470937) was a randomized study based on the hypothesis that improving postprandial glucose excursions with acarbose would slow the progression of fasting hyperglycaemia in screen-detected type 2 diabetes. In the Early Diabetes Intervention Programme, the effect of acarbose plus lifestyle advice on progression of fasting hyperglycaemia over a 5-year period was not greater than that of placebo. However, there was an early glucose-lowering effect of the trial. The objective of the current secondary analysis was to describe ß-cell function changes in response to glucose lowering. METHODS: Participants were overweight adult subjects with screen-detected type 2 diabetes. ß-cell function was measured using hyperglycaemic clamps and oral glucose tolerance testing. The primary outcome was the change in ß-cell function from baseline to year 1, the time point where the maximal glucose-lowering effect was seen. RESULTS: At baseline, participants exhibited markedly impaired first-phase insulin response. Despite significant reductions in weight, fasting plasma glucose (PG) and 2-h PG, there was no clinically significant improvement in the first-phase insulin response. Late-phase insulin responses declined despite beneficial glycaemic effects of interventions. CONCLUSIONS: Insulin secretion is already severely impaired in early, screen-detected type 2 diabetes. Effective glucose-lowering intervention with acarbose was not sufficient to improve insulin secretion or halt the decline of ß-cell function.

Insulin Dynamics and Pathophysiology in Youth-Onset Type 2 Diabetes.

Youth-onset type 2 diabetes (T2D) is increasing around the globe. The increased disease burden of youth-onset T2D portends substantial consequences for the health outcomes of young people and for health care systems. The pathophysiology of this condition is characterized by insulin resistance and initial insulin hypersecretion +/- an inherent insulin secretory defect, with progressive loss of stimulated insulin secretion leading to pancreatic ß-cell failure. Research studies focusing on youth-onset T2D have illuminated key differences for youth- versus adult-onset T2D, with youth having more profound insulin resistance and quicker progression to loss of sufficient insulin secretion to maintain euglycemia. Therapies targeted to improve both insulin resistance and, importantly, maintain sufficient insulin secretory function over the lifespan in youth-onset T2D are needed.

Predictors of glycemic worsening in the next year in adults with screen-detected type 2 diabetes.

Background and Aims: Identifying simple markers of risk for worsening glucose can allow care providers to target therapeutic interventions according to risk of worsening glycemic control. We aimed to determine which routine clinical measures herald near-term glycemic worsening in early type 2 diabetes(T2D). Methods: The Early Diabetes Intervention Program (EDIP) was a clinical trial in individuals with screendetected T2D [HbA1C 6.3+0.63%(45+5mmol/mol)]. During the trial some participants experienced worsening fasting blood glucose (FBG). We investigated the time course of FBG, HbA1c, weight, and other clinical factors to determine which might herald glycemic worsening over the next year. Results: Progressors (62/219, 28.5%) had higher FBG than non-progressors at baseline [118 vs 130mg/dL (6.6 vs 7.2 mmol/L), p=<0.001]. FBG was stable except in the year of progression, when progressors exhibited a large 1-year rise [mean change 14.2mg/dL(0.79 mmol/L)]. Current FBG and antecedent year change in FBG were associated with progression(p<0.01), although the magnitude of change was too small to be of clinical utility (0.19 mg/dL; 0.01 mmol/L). Current or antecedent year change in HbA1c, weight, TG or HDL were not associated with progression. In the year of glycemic worsening, rising glucose was strongly associated with a concurrent increase in weight (p<0.001). Conclusions: Elevated FBG but not HbA1c identified individuals at risk for imminent glycemic worsening; the subsequent large rise in glucose was associated with a short-term increase in weight. Glucose and weight surveillance provide actionable information for those caring for patients with early diabetes.

Dulaglutide and Glomerular Hyperfiltration, Proteinuria, and Albuminuria in Youth With Type 2 Diabetes: Post Hoc Analysis of the AWARD-PEDS Study.

OBJECTIVE: To examine changes in glomerular hyperfiltration and other measures of kidney function in youth with type 2 diabetes treated with dulaglutide or placebo. RESEARCH DESIGN AND METHODS: Post hoc analysis was performed on kidney laboratory data from 154 youths (age 10-18 years) with type 2 diabetes enrolled in a completed placebo-controlled glycemic control trial of dulaglutide. RESULTS: Mean estimated glomerular filtration rate (eGFR) decreased from baseline to 26 weeks in participants treated with dulaglutide versus placebo (-5.8 vs. -0.1 mL/min/1.73 m2; P = 0.016). Decreases in eGFR were observed primarily in participants with baseline glomerular hyperfiltration. At 26 weeks, the prevalence of both glomerular hyperfiltration and proteinuria increased with placebo but decreased with dulaglutide (P = 0.014 and 0.004 vs. placebo, respectively). CONCLUSIONS: Dulaglutide was associated with attenuated glomerular hyperfiltration and proteinuria in youth with type 2 diabetes. The impact of these changes on the risk of diabetic kidney disease is unclear.