Presentation of youth with type 2 diabetes in the Pediatric Diabetes Consortium

OBJECTIVE

Type 2 diabetes (T2D) in youth is recognized as a pediatric disease, but few reports describe the characteristics during diagnosis. We describe the clinical presentation of 503 youth with T2D.

METHODS

The Pediatric Diabetes Consortium (PDC) T2D Clinic Registry enrolled T2D participants from eight pediatric diabetes centers in the USA. Clinical and laboratory characteristics at the time of diagnosis were analyzed.

RESULTS

In total 67% presented with symptoms of diabetes and confirming laboratory data, but 33% were identified by testing at risk children, 11% presented with diabetic ketoacidosis (DKA), and 2% with hyperglycemic hyperosmolar state (HHS). The mean age was 13.1 ± 2.3 yr (range, 4.6-19.8 yr) with 38 (8%) less than 10 yr of age at diagnosis. The majority was female (65%), Hispanic (54%) and had a family history of T2D (92%). The median body mass index (BMI) z-score was 2.3 (interquartile range 2.0-2.6). Fewer than half (46%) lived with both parents, only 30% had parents with education beyond high school, and 43% lived in a household with an income of <$25 000 per year. In the initial month after diagnosis, almost all (92%) were treated with insulin (30%), metformin (31%), or a combination of insulin and metformin (32%); 7% were treated with lifestyle modification alone.

CONCLUSIONS

The demographics of T2D in youth indicate significant social vulnerability which may affect outcomes. Metformin and insulin were the initial treatment in most youth. Importantly, T2D may occur at younger ages than previously thought and should be considered in all high-risk children presenting with diabetes.

C-peptide levels in pediatric type 2 diabetes in the Pediatric Diabetes Consortium T2D Clinic Registry

OBJECTIVE

To describe C-peptide levels in a large cohort of children with type 2 diabetes T2D and examine associations with demographic and clinical factors.

METHODS

The Pediatric Diabetes Consortium (PDC) T2D Registry has collected clinical and biologic data from youth with T2D cared for at eight US Pediatric Diabetes Centers. In this study, we assessed C-peptide levels in 331 youth with T2D (mean age, 16.1 ± 2.5 yr; median T2D duration, 2.4 yr).

RESULTS

Median (interquartile range) for 90 fasted C-peptide measurements was 3.5 ng/mL (2.3-4.8 ng/mL) [1.2 nmol/L (0.8-1.6 nmol/L)] and for 241 random non-fasted C-peptide measurements were 4.2 ng/mL (2.6-7.0 ng/mL) [1.4 nmol/L (0.9-2.3 nmol/L)]. C-peptide levels were lower with insulin therapy (p < 0.001), lower body mass index (p < 0.001), hemoglobin A1c (HbA1c) ≥9% (p < 0.001), and T2D duration ≥ 6 yr (p = 0.04). Among those with duration ≥6 yr being treated with insulin and with a HbA1c level ≥9.0% (75 mmol/L), 75% of the fasted and 80% of the non-fasted C-peptide values were above 0.2 nmol/L.

CONCLUSIONS

In youth with T2D, a decline in C-peptide is associated with deterioration of metabolic control and the need for insulin treatment. C-peptide levels decrease over time. However, even insulin-treated patients with 6 or more years of T2D and elevated HbA1c levels retain substantial endogenous insulin secretion.

Changes in beta cell function during the proximate post-diagnosis period in persons with type 1 diabetes

OBJECTIVE

Prior studies examining beta-cell preservation in type 1 diabetes have predominantly assessed stimulated C-peptide concentrations approximately 10 wk after diagnosis. We examined whether earlier assessments might aid in prediction of beta cell function over time.

METHODS

Using data from a multi-center randomized trial assessing the effect of intensive diabetes management initiated within 1 wk of diagnosis, we assessed which clinical factors predicted 90-min mixed-meal tolerance test (MMTT) stimulated C-peptide values obtained 2 and 6 wk after diagnosis. We also studied associations of these factors with C-peptide values at 1- and 2-year post-diagnosis. Data from intervention and control groups were pooled.

RESULTS

Among 67 study participants (mean age 13.3 ± 5.7 yr, range 7.8-45.7 yr) in multivariable analyses, C-peptide increased from baseline to 2 wks and then 6 wk. C-peptide levels at these times were significantly correlated with 1- and 2-yr C-peptide concentrations (all p < 0.001), with the strongest observed associations between 6-wk C-peptide and the 1- and 2-yr values (r = 0.66 and r = 0.61, respectively). In multivariable analyses, greater baseline and 6-wk C-peptide, and older age independently predicted greater 1- and 2-yr C-peptide concentrations.

CONCLUSIONS

C-peptide assessments close to diagnosis were predictive of subsequent C-peptide production. Our data demonstrate a clear increase in C-peptide over the initial 6 wk after diabetes diagnosis followed by a plateau. Our data do not suggest that MMTT assessments performed closer to diagnosis than 6 wk would improve prediction of subsequent residual beta cell function.

Glucagon Nasal Powder: A Promising Alternative to Intramuscular Glucagon in Youth With Type 1 Diabetes

OBJECTIVE

Treatment of severe hypoglycemia outside of the hospital setting is limited to intramuscular glucagon requiring reconstitution prior to injection. The current study examined the safety and dose-response relationships of a needle-free intranasal glucagon preparation in youth aged 4 to <17 years.

RESEARCH DESIGN AND METHODS

A total of 48 youth with type 1 diabetes completed the study at seven clinical centers. Participants in the two youngest cohorts (4 to <8 and 8 to <12 years old) were randomly assigned to receive either 2 or 3 mg intranasal glucagon in two separate sessions or to receive a single, weight-based dose of intramuscular glucagon. Participants aged 12 to <17 years received 1 mg intramuscular glucagon in one session and 3 mg intranasal glucagon in the other session. Glucagon was given after glucose was lowered to <80 mg/dL (mean nadir ranged between 67 and 75 mg/dL).

RESULTS

All 24 intramuscular and 58 of the 59 intranasal doses produced a ≥25 mg/dL rise in glucose from nadir within 20 min of dosing. Times to peak plasma glucose and glucagon levels were similar under both intramuscular and intranasal conditions. Transient nausea occurred in 67% of intramuscular sessions versus 42% of intranasal sessions (P = 0.05); the efficacy and safety of the 2- and 3-mg intranasal doses were similar in the youngest cohorts.

CONCLUSIONS

Results of this phase 1, pharmacokinetic, and pharmacodynamic study support the potential efficacy of a needle-free glucagon nasal powder delivery system for treatment of hypoglycemia in youth with type 1 diabetes. Given the similar frequency and transient nature of adverse effects of the 2- and 3-mg intranasal doses in the two youngest cohorts, a single 3-mg intranasal dose appears to be appropriate for use across the entire 4- to <17-year age range.

Longitudinal Evaluation of Cognitive Functioning in Young Children with Type 1 Diabetes over 18 Months

OBJECTIVES

Decrements in cognitive function may already be evident in young children with type 1 diabetes (T1D). Here we report prospectively acquired cognitive results over 18 months in a large cohort of young children with and without T1D.

METHODS

A total of 144 children with T1D (mean HbA1c: 7.9%) and 70 age-matched healthy controls (mean age both groups 8.5 years; median diabetes duration 3.9 years; mean age of onset 4.1 years) underwent neuropsychological testing at baseline and after 18-months of follow-up. We hypothesized that group differences observed at baseline would be more pronounced after 18 months, particularly in those T1D patients with greatest exposure to glycemic extremes.

RESULTS

Cognitive domain scores did not differ between groups at the 18 month testing session and did not change differently between groups over the follow-up period. However, within the T1D group, a history of diabetic ketoacidosis (DKA) was correlated with lower Verbal IQ and greater hyperglycemia exposure (HbA1c area under the curve) was inversely correlated to executive functions test performance. In addition, those with a history of both types of exposure performed most poorly on measures of executive function.

CONCLUSIONS

The subtle cognitive differences between T1D children and nondiabetic controls observed at baseline were not observed 18 months later. Within the T1D group, as at baseline, relationships between cognition (Verbal IQ and executive functions) and glycemic variables (chronic hyperglycemia and DKA history) were evident. Continued longitudinal study of this T1D cohort and their carefully matched healthy comparison group is planned.

Intranasal Glucagon for Treatment of Insulin-Induced Hypoglycemia in Adults With Type 1 Diabetes: A Randomized Crossover Noninferiority Study

OBJECTIVE

Treatment of severe hypoglycemia with loss of consciousness or seizure outside of the hospital setting is presently limited to intramuscular glucagon requiring reconstitution immediately prior to injection, a process prone to error or omission. A needle-free intranasal glucagon preparation was compared with intramuscular glucagon for treatment of insulin-induced hypoglycemia.

RESEARCH DESIGN AND METHODS

At eight clinical centers, a randomized crossover noninferiority trial was conducted involving 75 adults with type 1 diabetes (mean age, 33 ± 12 years; median diabetes duration, 18 years) to compare intranasal (3 mg) versus intramuscular (1 mg) glucagon for treatment of hypoglycemia induced by intravenous insulin. Success was defined as an increase in plasma glucose to ≥70 mg/dL or ≥20 mg/dL from the glucose nadir within 30 min after receiving glucagon.

RESULTS

Mean plasma glucose at time of glucagon administration was 48 ± 8 and 49 ± 8 mg/dL at the intranasal and intramuscular visits, respectively. Success criteria were met at all but one intranasal visit and at all intramuscular visits (98.7% vs. 100%; difference 1.3%, upper end of 1-sided 97.5% CI 4.0%). Mean time to success was 16 min for intranasal and 13 min for intramuscular (P < 0.001). Head/facial discomfort was reported during 25% of intranasal and 9% of intramuscular dosing visits; nausea (with or without vomiting) occurred with 35% and 38% of visits, respectively.

CONCLUSIONS

Intranasal glucagon was highly effective in treating insulin-induced hypoglycemia in adults with type 1 diabetes. Although the trial was conducted in a controlled setting, the results are applicable to real-world management of severe hypoglycemia, which occurs owing to excessive therapeutic insulin relative to the impaired or absent endogenous glucagon response.

Depressive Symptoms in Youth With Type 1 or Type 2 Diabetes: Results of the Pediatric Diabetes Consortium Screening Assessment of Depression in Diabetes Study

OBJECTIVE

To evaluate the frequency of depressive symptoms and the diagnosis and management of depression in youth with type 1 diabetes (T1D) and type 2 diabetes (T2D) enrolled in the Pediatric Diabetes Consortium T1D and T2D registries.

RESEARCH DESIGN AND METHODS

The Children's Depression Inventory (CDI) 2 Self-Report (Short) version was completed by 261 T1D and 339 T2D youth aged 10-17 years.

RESULTS

Symptoms of depression were identified in 13% of T1D and 22% of T2D (P = 0.007) participants; of these, only 4% of T1D and 9% of T2D youth were treated by a therapist within the prior 12 months. Depressive symptoms were associated with lower family income (P = 0.006) and obesity (P = 0.002) in T1D but not T2D youth.

CONCLUSIONS

Depressive symptoms are more frequent than diagnosed depression in youth with T1D or T2D. These results underscore the need for regular depression screening and appropriate referral for youth with diabetes.

CGM-measured glucose values have a strong correlation with C-peptide, HbA1c and IDAAC, but do poorly in predicting C-peptide levels in the two years following onset of diabetes

AIMS/HYPOTHESIS

The aim of this work was to assess the association between continuous glucose monitoring (CGM) data, HbA1c, insulin-dose-adjusted HbA1c (IDAA1c) and C-peptide responses during the first 2 years following diagnosis of type 1 diabetes.

METHODS

A secondary analysis was conducted of data collected from a randomised trial assessing the effect of intensive management initiated within 1 week of diagnosis of type 1 diabetes, in which mixed-meal tolerance tests were performed at baseline and at eight additional time points through 24 months. CGM data were collected at each visit.

RESULTS

Among 67 study participants (mean age [± SD] 13.3 ± 5.7 years), HbA1c was inversely correlated with C-peptide at each time point (p < 0.001), as were changes in each measure between time points (p < 0.001). However, C-peptide at one visit did not predict the change in HbA1c at the next visit and vice versa. Higher C-peptide levels correlated with increased proportion of CGM glucose values between 3.9 and 7.8 mmol/l and lower CV (p = 0.001 and p = 0.02, respectively) but not with CGM glucose levels <3.9 mmol/l. Virtually all participants with IDAA1c < 9 retained substantial insulin secretion but when evaluated together with CGM, time in the range of 3.9-7.8 mmol/l and CV did not provide additional value in predicting C-peptide levels.

CONCLUSIONS/INTERPRETATION

In the first 2 years after diagnosis of type 1 diabetes, higher C-peptide levels are associated with increased sensor glucose levels in the target range and with lower glucose variability but not hypoglycaemia. CGM metrics do not provide added value over the IDAA1c in predicting C-peptide levels.

Evolution of abnormal plasma glucagon responses to mixed-meal feedings in youth with type 1 diabetes during the first 2 years after diagnosis

OBJECTIVE

To examine the evolution of the dysregulated glucagon responses to mixed-meal tolerance tests (MMTTs) in youth with recent-onset type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

MMTTs were performed in 25 youth (9-18 years of age) with 1.5-12 months disease duration (year 1); 22 subjects were restudied 1 year later (year 2). Twenty nondiabetic (ND) control children were also studied.

RESULTS

In T1D children, MMTT-stimulated increases in glucagon were significantly greater than that in ND children (median increments: year 1, 21 pg/mL [16-30]; year 2, 25 pg/mL [16-30]; ND, 9 pg/mL [5-16]; P = 0.001 and P < 0.001, respectively).

CONCLUSIONS

In comparison with ND control children, exaggerated plasma glucagon responses to mixed-meal feedings are observed in youth with T1D within the first 2 years of diagnosis. Further studies to determine whether suppression of these abnormal responses may help to improve glycemic control are warranted.

Pediatric diabetes consortium T1D New Onset (NeOn) study: clinical outcomes during the first year following diagnosis

OBJECTIVE

There have been few prospective, multicenter studies investigating the natural history of type 1 diabetes (T1D) from the time of diagnosis. The objective of this report from the Pediatric Diabetes Consortium (PDC) T1D New Onset (NeOn) study was to assess the natural history and clinical outcomes in children during the first year after diagnosis of T1D.

RESEARCH DESIGN AND METHODS

Clinical measures from the first year following diagnosis were analyzed for 857 participants (mean age 9.1 yr, 51% female, 66% non-Hispanic White) not participating in an intervention study who had a HbA1c result at 12 months.

RESULTS

Mean HbA1c ± SD was 102 ± 25 mmol/mol (11.4 ± 2.3%) at diagnosis, 55 ± 12 mmol/mol (7.2 ± 1.1%) at 3 months, 56 ± 15 mmol/mol (7.3 ± 1.3%) at 6 months and 62 ± 16 mmol/mol (7.8 ± 1.5%) at 12 months from diagnosis. A severe hypoglycemic (SH) event occurred in 31 (4%) participants (44 events, 5.2 events per 100 person-years). Diabetic ketoacidosis (DKA) not including diagnosis occurred in 10 (1%) participants (13 events, 1.5 events per 100 person-years).

CONCLUSIONS

After onset of T1D, mean HbA1c reaches its nadir at 3-6 months with a gradual increase through 12 months. SH and DKA are uncommon but still occur during the first year with T1D. Data from large cohorts, such as the PDC T1D NeOn study, provide important insights into the course of T1D during the first year following diagnosis, which will help to inform the development of models to target future interventions.

Pediatric Diabetes Consortium Type 1 Diabetes New Onset (NeOn) Study: factors associated with HbA1c levels one year after diagnosis

OBJECTIVE

To identify determinants of hemoglobin A1c (HbA1c) levels 1 yr after the diagnosis of type 1 diabetes (T1D) in participants in the Pediatric Diabetes Consortium (PDC) T1D New Onset (NeOn) Study.

RESEARCH DESIGN AND METHODS

Diabetes-specific as well as socioeconomic factors during the first year following diagnosis were analyzed in 857 participants (mean age 9.1 yrs, 51% female, 66% non-Hispanic White) not participating in an intervention study who had an HbA1c value at 12 months.

RESULT

Mean ± SD HbA1c at 1 yr was 62 ± 16 mmol/mol (7.8% ± 1.5). In univariate and multivariate analyses, clinical center, non-Hispanic White race, private health insurance, living with both parents, higher frequency of self-monitoring of blood glucose (SMBG), and lower insulin requirements were associated with lower HbA1c concentrations at 1 yr (p < 0.01). No association was found with gender, age, Tanner stage, body mass index (BMI), diabetic ketoacidosis (DKA) at onset, number of positive autoantibodies or HbA1c at onset, or number of visits to diabetes physician during the first year.

CONCLUSIONS

White race, higher socioeconomic status, two-parent household, more frequent SMBG, and low insulin requirements are associated with lower HbA1c concentration 1 yr after the onset of T1D in children.

Blunted glucagon but not epinephrine responses to hypoglycemia occurs in youth with less than 1 yr duration of type 1 diabetes mellitus

CONTEXT

Glycemic control is limited by the barrier of hypoglycemia. Recurrent hypoglycemia impairs counterregulatory (CR) hormone responses to subsequent hypoglycemia.

OBJECTIVE

To determine the glucagon and epinephrine responses to insulin-induced hypoglycemia in adolescents with recent-onset type 1 diabetes mellitus (T1DM).

METHODS

We assessed the CR responses to hypoglycemia by performing a hyperinsulinemic (2.0 mU/kg/min), euglycemic (BG 90 mg/dL; 5.0 mmol/L)-hypoglycemic (BG 55 mg/dL; 3.0 mmol/L) clamp in 25 recent-onset (<1 yr duration) patients 9-18 yr old (mean ± SD: 13.4 ± 2.7) with T1DM and 16 non-diabetic controls 19-25 yr old (mean ± SD 23.3 ± 1.8). Twenty of the T1DM subjects were retested 1-yr (53 ± 3 wk) later.

RESULTS

At the initial and 1-yr studies, peak glucagon (pGON) and incremental glucagon (ΔGON) during hypoglycemia were lower in the T1DM subjects [median pGON = 47 pg/mL (quartiles: 34, 72), ΔGON = 16 (4, 27) initially and pGON = 50 pg/mL (42, 70), ΔGON = 12 (9, 19) at 1-yr] than in controls [pGON = 93 pg/mL (60, 111); ΔGON = 38 pg/mL (19, 66), p = 0.01 and p = 0.004 for ΔGON at initial and 1-yr study, respectively]. In contrast, peak epinephrine (pEPI) and incremental epinephrine (ΔEPI) levels were similar in the T1DM (pEPI = 356 pg/mL (174, 797) and ΔEPI = 322 pg/mL (143, 781) initially and pEPI = 469 pg/mL (305, 595) and ΔEPI = 440 pg/mL (285, 574) at 1 yr) and in controls (pEPI = 383 pg/mL (329, 493) and ΔEPI = 336 pg/mL (298, 471) p = 0.97 and 0.21 for ΔEPI at initial and 1-yr study, respectively).

CONCLUSIONS

Even within the first year of T1DM, glucagon responses to hypoglycemia are blunted but epinephrine responses are not, suggesting that the mechanisms involved in the loss of these hormonal responses, which are key components in pathophysiology of hypoglycemia-associated autonomic failure, are different.

High success rates of sedation-free brain MRI scanning in young children using simple subject preparation protocols with and without a commercial mock scanner--the Diabetes Research in Children Network (DirecNet) experience

BACKGROUND

The ability to lie still in an MRI scanner is essential for obtaining usable image data. To reduce motion, young children are often sedated, adding significant cost and risk.

OBJECTIVE

We assessed the feasibility of using a simple and affordable behavioral desensitization program to yield high-quality brain MRI scans in sedation-free children.

MATERIALS AND METHODS

222 children (4-9.9 years), 147 with type 1 diabetes and 75 age-matched non-diabetic controls, participated in a multi-site study focused on effects of type 1 diabetes on the developing brain. T1-weighted and diffusion-weighted imaging (DWI) MRI scans were performed. All children underwent behavioral training and practice MRI sessions using either a commercial MRI simulator or an inexpensive mock scanner consisting of a toy tunnel, vibrating mat, and video player to simulate the sounds and feel of the MRI scanner.

RESULTS

205 children (92.3%), mean age 7 ± 1.7 years had high-quality T1-W scans and 174 (78.4%) had high-quality diffusion-weighted scans after the first scan session. With a second scan session, success rates were 100% and 92.5% for T1-and diffusion-weighted scans, respectively. Success rates did not differ between children with type 1 diabetes and children without diabetes, or between centers using a commercial MRI scan simulator and those using the inexpensive mock scanner.

CONCLUSION

Behavioral training can lead to a high success rate for obtaining high-quality T1-and diffusion-weighted brain images from a young population without sedation.

Alterations in white matter structure in young children with type 1 diabetes

OBJECTIVE

To investigate whether type 1 diabetes affects white matter (WM) structure in a large sample of young children.

RESEARCH DESIGN AND METHODS

Children (ages 4 to <10 years) with type 1 diabetes (n = 127) and age-matched nondiabetic control subjects (n = 67) had diffusion weighted magnetic resonance imaging scans in this multisite neuroimaging study. Participants with type 1 diabetes were assessed for HbA1c history and lifetime adverse events, and glucose levels were monitored using a continuous glucose monitor (CGM) device and standardized measures of cognition.

RESULTS

Between-group analysis showed that children with type 1 diabetes had significantly reduced axial diffusivity (AD) in widespread brain regions compared with control subjects. Within the type 1 diabetes group, earlier onset of diabetes was associated with increased radial diffusivity (RD) and longer duration was associated with reduced AD, reduced RD, and increased fractional anisotropy (FA). In addition, HbA1c values were significantly negatively associated with FA values and were positively associated with RD values in widespread brain regions. Significant associations of AD, RD, and FA were found for CGM measures of hyperglycemia and glucose variability but not for hypoglycemia. Finally, we observed a significant association between WM structure and cognitive ability in children with type 1 diabetes but not in control subjects.

CONCLUSIONS

These results suggest vulnerability of the developing brain in young children to effects of type 1 diabetes associated with chronic hyperglycemia and glucose variability.

Neuroanatomical correlates of dysglycemia in young children with type 1 diabetes

Studies of brain structure in type 1 diabetes (T1D) describe widespread neuroanatomical differences related to exposure to glycemic dysregulation in adults and adolescents. In this study, we investigate the neuroanatomical correlates of dysglycemia in very young children with early-onset T1D. Structural magnetic resonance images of the brain were acquired in 142 children with T1D and 68 age-matched control subjects (mean age 7.0 ± 1.7 years) on six identical scanners. Whole-brain volumetric analyses were conducted using voxel-based morphometry to detect regional differences between groups and to investigate correlations between regional brain volumes and measures of glycemic exposure (including data from continuous glucose monitoring). Relative to control subjects, the T1D group displayed decreased gray matter volume (GMV) in bilateral occipital and cerebellar regions (P < 0.001) and increased GMV in the left inferior prefrontal, insula, and temporal pole regions (P = 0.002). Within the T1D group, hyperglycemic exposure was associated with decreased GMV in medial frontal and temporal-occipital regions and increased GMV in lateral prefrontal regions. Cognitive correlations of intelligence quotient to GMV were found in cerebellar-occipital regions and medial prefrontal cortex for control subjects, as expected, but not for the T1D group. Thus, early-onset T1D affects regions of the brain that are associated with typical cognitive development.

Effectiveness of early intensive therapy on β-cell preservation in type 1 diabetes

OBJECTIVE

To assess effectiveness of inpatient hybrid closed-loop control (HCLC) followed by outpatient sensor-augmented pump (SAP) therapy initiated within 7 days of diagnosis of type 1 diabetes on the preservation of β-cell function at 1 year.

RESEARCH DESIGN AND METHODS

Sixty-eight individuals (mean age 13.3 ± 5.7 years; 35% female, 92% Caucasian) were randomized to HCLC followed by SAP therapy (intensive group; N = 48) or to the usual-care group treated with multiple daily injections or insulin pump therapy (N = 20). Primary outcome was C-peptide concentrations during mixed-meal tolerance tests at 12 months.

RESULTS

Intensive-group participants initiated HCLC a median of 6 days after diagnosis for a median duration of 71.3 h, during which median participant mean glucose concentration was 140 mg/dL (interquartile range 134-153 mg/dL). During outpatient SAP, continuous glucose monitor (CGM) use decreased over time, and at 12 months, only 33% of intensive participants averaged sensor use ≥6 days/week. In the usual-care group, insulin pump and CGM use were initiated prior to 12 months by 15 and 5 participants, respectively. Mean HbA1c levels were similar in both groups throughout the study. At 12 months, the geometric mean (95% CI) of C-peptide area under the curve was 0.43 (0.34-0.52) pmol/mL in the intensive group and 0.52 (0.32-0.75) pmol/mL in the usual-care group (P = 0.49). Thirty-seven (79%) intensive and 16 (80%) usual-care participants had a peak C-peptide concentration ≥0.2 pmol/mL (P = 0.30).

CONCLUSIONS

In new-onset type 1 diabetes, HCLC followed by SAP therapy did not provide benefit in preserving β-cell function compared with current standards of care.

Race, socioeconomic status, and treatment center are associated with insulin pump therapy in youth in the first year following diagnosis of type 1 diabetes

BACKGROUND

Increasing numbers of children and adolescents with type 1 diabetes (T1D) have been placed on insulin pump therapy. Nevertheless, data are limited regarding patterns of pump use during the first year of treatment and the clinical and socioeconomic factors associated with early use of pump therapy. Therefore, we sought to determine factors associated with pump therapy within the first year of diagnosis in youth enrolled in the Pediatric Diabetes Consortium (PDC) T1D New-Onset (NeOn) Study.

SUBJECTS AND METHODS

The NeOn Study includes youth <19 years old at T1D diagnosis who have been followed from the time of diagnosis at seven U.S. pediatric diabetes centers. Cox regression was used to determine factors associated with transition from injection to pump therapy during the first year of T1D in 1,012 participants.

RESULTS

Twenty-seven percent (n=254) of participants began pump therapy within the first year of diagnosis, ranging from 18% to 59% among the seven centers. After adjusting for center effect, factors associated with pump use in multivariate analysis included private health insurance (37% vs. 7%; P<0.001), having annual household income over $100,000 (50% vs. 15%; P<0.001), and non-Hispanic white race (36% vs. 11%; P<0.001). The hemoglobin A1c level did not appear to influence the decision to initiate pump use.

CONCLUSIONS

Participants of non-Hispanic white race and higher socioeconomic status were more likely to be placed on pumps during the first year. Further investigations are needed to gain a better understanding of barriers to use of pumps in youth with T1D, especially in disadvantaged and minority families.

Lack of association between residual insulin production and glucagon response to hypoglycemia in youth with short duration of type 1 diabetes

OBJECTIVE

To examine the loss of glucagon response to hypoglycemia and its relationship with residual β-cell function early in the course of type 1 diabetes (T1D) in youth.

RESEARCH DESIGN AND METHODS

Twenty-one youth with T1D duration <1 year (ages 8-18 years, T1D duration 6-52 weeks) underwent mixed-meal tolerance tests (MMTTs) to assess residual β-cell function and hypoglycemic clamps to assess glucagon responses to hypoglycemia. Glucagon responses to hypoglycemia in T1D subjects were compared with those in 12 nondiabetic young adults (ages 19-25 years).

RESULTS

Peak MMTT-stimulated C-peptide levels (range 0.12-1.43) were ≥ 0.2 nmol/L in all but one T1D subject. As expected, the median of glucagon responses to hypoglycemia in the T1D subjects (18 pg/mL [interquartile range 7-32]) was significantly reduced compared with the responses in nondiabetic control subjects (38 pg/mL [19-66], P = 0.02). However, there was no correlation between the incremental increase in plasma glucagon during the hypoglycemic clamp and the incremental increase and peak plasma C-peptide level during the MMTT. Similarly, the seven T1D subjects who failed to achieve an increase in glucagon ≥ 12 pg/mL (i.e., 3 SD above baseline values) had C-peptide response ≥ 0.2 nmol/L (0.54-1.12), and the one T1D subject with peak stimulated <0.2 nmol/L had a 14 pg/mL increase in plasma glucagon in response to hypoglycemia.

CONCLUSIONS

Impaired plasma glucagon responses to hypoglycemia are evident in youth with T1D during the first year of the disease. Moreover, defective and absent glucagon responses to hypoglycemia were observed in patients who retained clinically important residual endogenous β-cell function.

The effects of inpatient hybrid closed-loop therapy initiated within 1 week of type 1 diabetes diagnosis

BACKGROUND

This article describes our experience with inpatient hybrid closed-loop control (HCLC) initiated shortly after the diagnosis of type 1 diabetes in a randomized trial designed to assess the effectiveness of inpatient HCLC followed by outpatient sensor-augmented pump (SAP) therapy on the preservation of β-cell function.

SUBJECTS AND METHODS

Forty-eight individuals with newly diagnosed type 1 diabetes and positive pancreatic autoantibodies (7.8-37.7 years old) received inpatient HCLC therapy for up to 93 h, initiated within 7 days of diagnosis.

RESULTS

On initiation of HCLC, mean glucose concentration was 240±100 mg/dL. During the first day of HCLC, median of the participant's mean glucose concentrations fell rapidly to 146 mg/dL, a level of control that was sustained on Days 2 and 3 (138 mg/dL and 139 mg/dL, respectively). By Day 3, the median percentage of glucose values >250 and <60 mg/dL was <1%. During the first 2 weeks of SAP treatment at home, the median participant mean glucose level was 126 mg/dL (interquartile range, 117, 137 mg/dL), and the median percentage of values between 71 and 180 mg/dL was 85% (interquartile range, 80%, 90%).

CONCLUSIONS

Inpatient HCLC followed by outpatient SAP therapy can provide a safe and effective means to rapidly reverse glucose toxicity and establish near-normal glycemic control in patients with newly diagnosed type 1 diabetes.

Persistence of individual variations in glycated hemoglobin: analysis of data from the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Randomized Trial

OBJECTIVE

To determine the individual persistence of the relationship between mean sensor glucose (MG) concentrations and hemoglobin A(1c) (A1C) from the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring (CGM) Randomized Trial.

RESEARCH DESIGN AND METHODS

MG was calculated using CGM data for 3 months before A1C measurements at 3, 6, 9, and 12 months for the CGM group and at 9 and 12 months for the control group. An MG-to-A1C ratio was included in analysis for subjects who averaged ≥4 days/week of CGM use.

RESULTS

Spearman correlations of the MG-to-A1C ratio between consecutive visits 3 months apart ranged from 0.70 to 0.79. The correlations for children and youth were slightly smaller than those for adults. No meaningful differences were observed by device type or change in A1C.

CONCLUSIONS

Individual variations in the rate of hemoglobin glycation are persistent and contribute to the inaccuracy in estimating MGs calculated from A1C levels.

Optimal sampling intervals to assess long-term glycemic control using continuous glucose monitoring

AIMS AND HYPOTHESIS

The optimal duration and frequency of short-term continuous glucose monitoring (CGM) to reflect long-term glycemia have not been determined. The Juvenile Diabetes Research Foundation CGM randomized trials provided a large dataset of longitudinal CGM data for this type of analysis.

METHODS

The analysis included 185 subjects who had 334 3-month intervals of CGM data meeting specific criteria. For various glucose indices, correlations (r²) were computed for the entire 3-month interval versus selected sampling periods ranging from 3 to 15 days. Other computed agreement measures included median relative absolute difference, values within ± 10% and ± 20% of full value, and median absolute difference.

RESULTS

As would be expected, the more days of glucose data that were sampled, the higher the correlation with the full 3 months of data. For 3 days of sampling, the r² value ranged from 0.32 to 0.47, evaluating mean glucose, percentage of values 71-180 mg/dL, percentage of values > 180 mg/dL, percentage of values ≤ 70 mg/dL, and coefficient of variation; in contrast, for 15 days of sampling, the r² values ranged from 0.66 to 0.75. The results were similar when the analysis intervals were stratified by age group (8-14, 15-24, and ≥ 25 years), by baseline hemoglobin A1c level (< 7.0% and ≥ 7.0%), and by CGM device type.

CONCLUSIONS AND INTERPRETATION

Our data suggest that a 12-15-day period of monitoring every 3 months may be needed to optimally assess overall glucose control. Shorter periods of sampling can be useful, but the correlation with 3-month measures of glycemic control is lower.

Hemoglobin A1c and mean glucose in patients with type 1 diabetes: analysis of data from the Juvenile Diabetes Research Foundation continuous glucose monitoring randomized trial

OBJECTIVE

To determine the relationship between mean sensor glucose concentrations and hemoglobin A(1c) (HbA(1c)) values measured in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications laboratory at the University of Minnesota in a cohort of subjects with type 1 diabetes from the Juvenile Diabetes Research Foundation continuous glucose monitoring randomized trial.

RESEARCH DESIGN AND METHODS

Near-continuous glucose sensor data (≥ 4 days/week) were collected for 3 months before a central laboratory-measured HbA(1c) was performed for 252 subjects aged 8-74 years, the majority of whom had stable HbA(1c) values (77% within ± 0.4% of the patient mean).

RESULTS

The slope (95% CI) for mean sensor glucose concentration (area under the curve) versus a centrally measured HbA(1c) was 24.4 mg/dL (22.0-26.7) for each 1% change in HbA(1c), with an intercept of -16.2 mg/dL (-32.9 to 0.6). Although the slope did not vary with age or sex, there was substantial individual variability, with mean sensor glucose concentrations ranging from 128 to 187 mg/dL for an HbA(1c) of 6.9-7.1%. The root mean square of the errors between the actual mean sensor glucose concentration versus the value calculated using the regression equation was 14.3 mg/dL, whereas the median absolute difference was 10.1 mg/dL.

CONCLUSIONS

There is substantial individual variability between the measured versus calculated mean glucose concentrations. Consequently, estimated average glucose concentrations calculated from measured HbA(1c) values should be used with caution.

Quality-of-life measures in children and adults with type 1 diabetes: Juvenile Diabetes Research Foundation Continuous Glucose Monitoring randomized trial

OBJECTIVE

To evaluate the impact of continuous glucose monitoring (CGM) on quality of life (QOL) among individuals with type 1 diabetes.

RESEARCH DESIGN AND METHODS

In a multicenter trial, 451 children and adults with type 1 diabetes were randomly assigned to CGM treatment or the control group. Generic and diabetes-specific QOL questionnaires were completed at baseline and 26 weeks by all participants and parents of participants <18 years old, and the CGM satisfaction scale was completed by the CGM group (participants and parents) at 26 weeks.

RESULTS

After 26 weeks, QOL scores remained largely unchanged for both the treatment and the control group, although there was a slight difference favoring the adult CGM group on several subscales (P < 0.05). There was substantial satisfaction with CGM technology after 26 weeks among participants and parents.

CONCLUSIONS

Baseline QOL was high, and the measures showed little change with CGM use, although a high level of CGM satisfaction was reported.

Continuous glucose monitoring in youth with type 1 diabetes: 12-month follow-up of the Juvenile Diabetes Research Foundation continuous glucose monitoring randomized trial

BACKGROUND

The use of continuous glucose monitoring (CGM) in the pediatric population is not well characterized. We have evaluated the use of CGM over a 12-month interval in youth with type 1 diabetes (TID) and have provided a description of CGM use.

METHODS

Eighty subjects 8-17 years old with T1D and baseline hemoglobin A1c (HbA1c) >or=7.0% used CGM as part of a 6-month randomized trial and subsequent 6-month extension study. Outcomes included frequency of CGM use, HbA1c levels, rate of severe hypoglycemia, and a CGM satisfaction scale.

RESULTS

Seventy-six (95%) of 80 subjects were using CGM after 6 months (median use = 5.5 days/week) compared with 67 (84%) after 12 months (median use = 4.0 days/week). The 17 subjects using CGM >or=6 days/week in month 12 had substantially greater improvement from baseline in HbA1c than did the 63 subjects using CGM <6 days/week in month 12 (mean change - 0.8 +/- 0.6% vs. +0.1 +/- 0.7%, P < 0.001). They also reported greater satisfaction with use of CGM (P = 0.001). The incidence of severe hypoglycemic events was low during the 12 months of the study irrespective of the amount of CGM use.

CONCLUSIONS

In youth with T1D, frequency of use decreases over time. Individuals who use CGM on a near-daily basis can have substantial improvement in glycemic control.