Patient reported outcomes (PROs) and user experiences of young children with type 1 diabetes using t:slim X2 insulin pump with control-IQ technology

OBJECTIVE

Examine patient-reported outcomes (PROs) after the use of t:slim X2 insulin pump with Control-IQ technology (CIQ) in young children with type 1 diabetes.

METHODS

Children with type 1 diabetes, ages 2 to < 6 years (n = 102), were randomly assigned 2:1 to either CIQ or standard care (SC) with pump or multiple daily injections (MDI) plus continuous glucose monitoring (CGM) for 13 weeks. Both groups were offered to use CIQ for an additional 13 weeks after the randomized control trial's (RCT) completion. Guardians completed PRO questionnaires at baseline, 13-, and 26-weeks examining hypoglycemia concerns, quality of life, parenting stress, and sleep. At 26 weeks, 28 families participated in user-experience interviews. Repeated measures analyses compared PRO scores between systems used.

RESULT

Comparing CIQ vs SC, responses on all 5 PRO surveys favored the CIQ group, showing that CIQ was superior to SC at 26 weeks (p values < 0.05). User-experience interviews indicated significant benefits in optimized glycemic control overall and nighttime control (28 of 28 families endorsed). All but 2/28 families noted substantial reduction in management burden resulting in less mental burden and all but 4 stated that they wanted their children to continue using CIQ.

CONCLUSIONS

Families utilizing CIQ experienced glycemic benefits coupled with substantial benefits in PROs, documented in surveys and interviews. Families utilizing CIQ had reduced hypoglycemia concerns and parenting stress, and improved quality of life and sleep. These findings demonstrate the benefit of CIQ in young children with type 1 diabetes that goes beyond documented glycemic benefit.

Multicenter, Randomized Trial of a Bionic Pancreas in Type 1 Diabetes

BACKGROUND

Currently available semiautomated insulin-delivery systems require individualized insulin regimens for the initialization of therapy and meal doses based on carbohydrate counting for routine operation. In contrast, the bionic pancreas is initialized only on the basis of body weight, makes all dose decisions and delivers insulin autonomously, and uses meal announcements without carbohydrate counting.

METHODS

In this 13-week, multicenter, randomized trial, we randomly assigned in a 2:1 ratio persons at least 6 years of age with type 1 diabetes either to receive bionic pancreas treatment with insulin aspart or insulin lispro or to receive standard care (defined as any insulin-delivery method with unblinded, real-time continuous glucose monitoring). The primary outcome was the glycated hemoglobin level at 13 weeks. The key secondary outcome was the percentage of time that the glucose level as assessed by continuous glucose monitoring was below 54 mg per deciliter; the prespecified noninferiority limit for this outcome was 1 percentage point. Safety was also assessed.

RESULTS

A total of 219 participants 6 to 79 years of age were assigned to the bionic-pancreas group, and 107 to the standard-care group. The glycated hemoglobin level decreased from 7.9% to 7.3% in the bionic-pancreas group and did not change (was at 7.7% at both time points) in the standard-care group (mean adjusted difference at 13 weeks, -0.5 percentage points; 95% confidence interval [CI], -0.6 to -0.3; P<0.001). The percentage of time that the glucose level as assessed by continuous glucose monitoring was below 54 mg per deciliter did not differ significantly between the two groups (13-week adjusted difference, 0.0 percentage points; 95% CI, -0.1 to 0.04; P<0.001 for noninferiority). The rate of severe hypoglycemia was 17.7 events per 100 participant-years in the bionic-pancreas group and 10.8 events per 100 participant-years in the standard-care group (P = 0.39). No episodes of diabetic ketoacidosis occurred in either group.

CONCLUSIONS

In this 13-week, randomized trial involving adults and children with type 1 diabetes, use of a bionic pancreas was associated with a greater reduction than standard care in the glycated hemoglobin level. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; ClinicalTrials.gov number, NCT04200313.).

Real-World Use of a New Hybrid Closed Loop Improves Glycemic Control in Youth with Type 1 Diabetes

Objective: To describe real-world outcomes for youth using the Tandem t:slim X2 insulin pump with Control-IQ technology ("Control-IQ") for 6 months at a large pediatric clinic. Methods: Youth with type 1 diabetes, who started Control-IQ for routine care, were prospectively followed. Data on system use and glycemic control were collected before Control-IQ start, and at 1, 3, and 6 months after start. Mixed models assessed change across time; interactions with baseline hemoglobin A1c (HbA1c) and age were tested. Results: In 191 youth (median age 14, 47% female, and median HbA1c 7.6%), percent time with glucose levels 70-180 mg/dL (time-in-range [TIR]) improved from 57% at baseline to 66% at 6 months (P < 0.001). The proportion of participants reaching TIR target (>70%) doubled from 23.5% at baseline to 47.8% at 3 months, sustaining at 46.7% at 6 months (P < 0.001). Glucose management indicator (approximation of HbA1c) improved from 7.5% at baseline to 7.1% at 3 months and 7.2% at 6 months (P < 0.001). Those with higher baseline HbA1c experienced the most substantial improvements in glycemic control. Percent time using the Control-IQ feature was 86.4% at 6 months, and <4% of cohort discontinued use. Conclusion: The Control-IQ system clinically and significantly improved glycemic control in a large sample of youth. System use was high at 6 months, with only a small proportion discontinuing use, indicating potential for sustaining results long term.

Accuracy of a breath ketone analyzer to detect ketosis in adults and children with type 1 diabetes

OBJECTIVE

To assess the accuracy of a breath ketone analyzer to detect ketosis in adults and children with type 1 diabetes.

RESEARCH DESIGN AND METHODS

This is a proof-of-concept, prospective study comparing breath ketone analyzer and blood ketone meter to detect ketosis.

RESULTS

A total of 500 measurements from 19 adults and children with type 1 diabetes were analyzed. There was a significant association between the breath ketone analyzer and blood ketone meter results in non-fasting adults (p = 0.0066), but not in children (p = 0.4579). In adults, a cut-off of 3.9 PPM on the breath ketone analyzer maximized the Youden Index with an AUC of 0.73. This cut-off for the breath ketone analyzer had 94.7% sensitivity and 54.2% specificity to detect ketosis (≥0.6 mmol/L in blood ketone meter).

CONCLUSIONS

The breath ketone analyzer may be considered as a non-invasive screening tool to rule out ketosis in adults with type 1 diabetes.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Sleep in Type 1 Diabetes: Implications for Glycemic Control and Diabetes Management

PURPOSE OF REVIEW

To highlight recent findings from studies of sleep in type 1 diabetes (T1D), with a focus on the role of sleep in self-management, the cognitive and psychosocial outcomes related to sleep disturbances, and factors associated with sleep disturbances specific to T1D.

RECENT FINDINGS

People with T1D experience higher rates of sleep disturbances than people without diabetes, and these disturbances have negative implications for glycemic control and diabetes management, as well as psychosocial and cognitive outcomes. Inconsistent sleep timing (bedtime and wake time) has emerged as a potential target for interventions, as variability in sleep timing has been linked with poorer glycemic control and adherence to treatment. Sleep-promoting interventions and new diabetes technology have the potential to improve sleep in people with T1D. Sleep is increasingly considered a critical factor in diabetes management, but more multi-method and longitudinal research is needed. We emphasize the importance of sufficient and consistent sleep for people with T1D, and the need for providers to routinely assess sleep among patients with T1D.

Preventing post-exercise nocturnal hypoglycemia in children with type 1 diabetes

OBJECTIVE

To determine the effects of reducing overnight basal insulin or a bedtime dose of terbutaline on nocturnal blood glucose (BG) nadir and hypoglycemia after exercise in children with type 1 diabetes mellitus.

STUDY DESIGN

Sixteen youth (mean age 13.3 years) on insulin pumps were studied overnight on 3 occasions after a 60-minute exercise session with BG measurements every 30 minutes. Admissions were randomized to bedtime treatment with oral terbutaline 2.5 mg, 20% basal rate insulin reduction for 6 hours, or no treatment.

RESULTS

Mean overnight nadir BG was 188 mg/dL after terbutaline and 172 mg/dL with basal rate reduction compared with 127 mg/dL on the control night (P = .002 and .042, respectively). Terbutaline eliminated nocturnal hypoglycemia but resulted in significantly more hyperglycemia (≥250 mg/dL) when compared with the control visit (P < .0001). The basal rate reduction resulted in fewer BG readings <80 and <70 mg/dL but more readings ≥250 mg/dL when compared with the control visit.

CONCLUSIONS

A basal insulin rate reduction was safe and effective in raising post-exercise nocturnal BG nadir and in reducing hypoglycemia in children with type 1 diabetes mellitus. Although effective at preventing hypoglycemia, a 2.5-mg dose of terbutaline was associated with hyperglycemia.

Prevention of nocturnal hypoglycemia using predictive alarm algorithms and insulin pump suspension

OBJECTIVE

The aim of this study was to develop a partial closed-loop system to safely prevent nocturnal hypoglycemia by suspending insulin delivery when hypoglycemia is predicted in type 1 diabetes.

RESEARCH DESIGN AND METHODS

Forty subjects with type 1 diabetes (age range 12-39 years) were studied overnight in the hospital. For the first 14 subjects, hypoglycemia (<60 mg/dl) was induced by gradually increasing the basal insulin infusion rate (without the use of pump shutoff algorithms). During the subsequent 26 patient studies, pump shutoff occurred when either three of five (n = 10) or two of five (n = 16) algorithms predicted hypoglycemia based on the glucose levels measured with the FreeStyle Navigator (Abbott Diabetes Care).

RESULTS

The standardized protocol induced hypoglycemia on 13 (93%) of the 14 nights. With use of a voting scheme that required three algorithms to trigger insulin pump suspension, nocturnal hypoglycemia was prevented during 6 (60%) of 10 nights. When the voting scheme was changed to require only two algorithms to predict hypoglycemia to trigger pump suspension, hypoglycemia was prevented during 12 (75%) of 16 nights. In the latter study, there were 25 predictions of hypoglycemia because some subjects had multiple hypoglycemic events during a night, and hypoglycemia was prevented for 84% of these events.

CONCLUSIONS

Using algorithms to shut off the insulin pump when hypoglycemia is predicted, it is possible to prevent hypoglycemia on 75% of nights (84% of events) when it would otherwise be predicted to occur.

Timing of meal insulin boluses to achieve optimal postprandial glycemic control in patients with type 1 diabetes

OBJECTIVE

This study determined the optimal timing of insulin bolus administration in relation to meal consumption in adolescents and adults with type 1 diabetes.

STUDY DESIGN AND METHODS

Twenty-three subjects participated in this crossover study consisting of three treatment arms: delivering an insulin glulisine bolus by insulin pump 20 min prior to a meal ("PRE"), immediately before the meal ("START"), and 20 min after meal initiation ("POST"). Blood glucose levels were measured every 30 min for a total of 240 min post-meal initiation. Mean blood glucose levels at 1 and 2 h after meal initiation, blood glucose area under the curve (AUC), and maximum blood glucose levels were analyzed.

RESULTS

At both 60 and 120 min after meal initiation, the PRE arm showed significantly lower glycemic excursions than the START arm (P = 0.0029 and 0.0294, respectively) and the POST arm (P = 0.001 and 0.0408, respectively). Glycemic AUC was significantly less in the PRE arm versus both the START and POST arms (159.5 +/- 58.9 mg/dL vs. 187.0 +/- 43.1 mg/dL [P = 0.0297] and 184.5 +/- 33.2 mg/dL [P = 0.0463], respectively). Peak blood glucose levels were significantly lower in the PRE arm compared to the START arm (P = 0.0039) and the POST arm (P = 0.0027).

CONCLUSIONS

A bolus of rapid-acting insulin 20 min prior to a meal results in significantly better postprandial glucose control than when the meal insulin bolus is given just prior to the meal or 20 min after meal initiation.

Continuous glucose monitoring in youth with type 1 diabetes

Continuous glucose monitoring (CGM) is becoming increasingly popular and represents the third era of diabetes management. Currently available CGM devices have been studied in youth with type 1 diabetes and show similar accuracy across all age groups. Tolerability of these devices relates to alarm settings, sensor skin irritation, and durability of the device. Youth will be most successful on a CGM regimen if they have a personal investment in wearing the CGM device and have a stable support system for their diabetes care. Data indicate that glycemic control improves the most in youth who wear CGM devices >or=5 days per week, allowing for the ability to make more insulin dose changes. CGM has proven useful in alerting youth to hypoglycemia and may be a valuable tool with exercise. Further studies are needed to assess the utility of CGM for prevention of severe hypoglycemic events and increasing time spent in euglycemia. Fear of hypoglycemia may be ameliorated with CGM use; however, the potential for increased stress in families with continuous feedback must also be considered. In the future, CGM use in youth may couple with insulin pump technology to create a "closed-loop" system in which the CGM device will direct insulin administration without user input.

Use of a subcutaneous injection port to improve glycemic control in children with type 1 diabetes

OBJECTIVE

To determine if use of an injection port, the Insuflon, would help to improve glycemic control in youth with type 1 diabetes (TID) who were in suboptimal glycemic control (hemoglobin A1c, HbA1c >8.0%).

STUDY DESIGN

A three-arm randomized protocol was used to study the effects of the Insuflon (a subcutaneous injection port) vs. an alarmable blood glucose meter vs. a control group on glycemic control in 66 youth with T1D. All participants used insulin glargine as their basal insulin and the NovoPen Junior with insulin aspart as their rapid-acting insulin. Participants were randomized into control, alarm, or Insuflon groups. HbA1c levels were the primary outcome with values at baseline, 3, and 6 months.

RESULTS

Initial parameters were similar in the three groups. HbA1c values were significantly lower for youth who used the Insuflon than for the control group at 3 and 6 months (p = 0.025). The HbA1c values (in %) for youth using the Insuflon decreased significantly from 9.4 at screening to 8.7 at 3 months (p < 0.001) and 8.5 at 6 months (p < 0.001). There were no significant reductions (p > or = 0.05) in the HbA1c values within the other two groups.

CONCLUSION

The Insuflon injection port helps some youth with T1D to improve glycemic control.

Preventing hypoglycemia using predictive alarm algorithms and insulin pump suspension

BACKGROUND

Nocturnal hypoglycemia is a significant problem. From 50% to 75% of hypoglycemia seizures occur at night. Despite the development of real-time glucose sensors (real-time continuous glucose monitor [CGM]) with hypoglycemic alarms, many patients sleep through these alarms. The goal of this pilot study was to assess the feasibility using a real-time CGM to discontinue insulin pump therapy when hypoglycemia was predicted.

METHODS

Twenty-two subjects with type 1 diabetes had two daytime admissions to a clinical research center. On the first admission their basal insulin was increased until their blood glucose level was <60 mg/dL. On the second admission hypoglycemic prediction algorithms were tested to determine if hypoglycemia was prevented by a 90-min pump shutoff and to determine if the pump shutoff resulted in rebound hyperglycemia.

RESULTS

Using a statistical prediction algorithm with an 80 mg/dL threshold and a 30-min projection horizon, hypoglycemia was prevented 60% of the time. Using a linear prediction algorithm with an 80 mg/dL threshold and a 45-min prediction horizon, hypoglycemia was prevented 80% of the time. There was no rebound hyperglycemia following pump suspension.

CONCLUSIONS

Further development of algorithms is needed to prevent all episodes of hypoglycemia from occurring.

Use of CoZmonitor in youth with type 1 diabetes

BACKGROUND

The purpose of this study was to evaluate the effectiveness of directly integrating self-monitoring blood glucose (BG) information with insulin pump therapy on overall glycemic control.

METHODS

In this randomized trial, 34 youth with type 1 diabetes using insulin pump therapy were trained on the use of the Deltec Cozmo Insulin Pump. Seventeen were randomized to use the CoZmonitor Blood Glucose Module, a device that attaches to the back of the pump using FreeStyle technology to perform BG tests which read directly on the pump screen. The remaining 17 (control group) used a FreeStyle Flash meter, a stand-alone BG meter, for their BG testing. At baseline, 3 and 6 months, the subjects filled out a questionnaire, had a hemoglobin A1c (HbA1c) test, and had pumps and meters downloaded.

RESULTS

After 3 months of study, there were no changes in mean HbA1c (+/- SD) values for the experimental (8.7 +/- 1.1 to 8.6 +/- 1.1) or the control groups (9.1 +/- 1.4 to 9.2 +/- 1.5). There were also no significant differences in HbA1c values after 6 months. The average number of BG tests per day did not change significantly in either group during the study. After 3 and 6 months, the experimental group rated satisfaction with the use of the CoZmonitor at 4.4 and 3.8 (respectively) on a five-point Likert scale, with 5 being the most satisfied.

CONCLUSIONS

Although significant changes in HbA1c values or the number of BG tests were not found, use of the BG module had a positive level of satisfaction.

Improved glycemic control after long-term insulin pump use in pediatric patients with type 1 diabetes

BACKGROUND

There are currently few data available on the long-term use of continuous subcutaneous insulin infusion (CSII) (insulin pump) therapy in children.

METHODS

Charts from 291 youth with type 1 diabetes (T1D) who were treated with CSII therapy for at least 1 year were reviewed. Data analysis included hemoglobin A(1c)(HbA(1c)) values, body mass index (BMI) values, and the occurrence of severe hypoglycemia (SH) or diabetic ketoacidosis (DKA) events.

RESULTS

For the 291 patients, the mean age (+/-SD) for beginning CSII therapy was 13.3 +/- 3.7 years. The mean duration of CSII was 3.7 +/- 1.9 years (range 1-9 years). The baseline HbA(1c) value was 8.7 +/- 1.0%, compared to 8.2 +/- 0.9% after 1 year (P < 0.0001). The most recent value for all patients was 8.3 +/- 1.3% (P < 0.0001 compared to the baseline values for the same subjects). There was no advantage in glycemic control in the teen years as a result of initiating CSII in the pre-teen years compared to the teen years. SH events decreased from 9.06 events per 100 patient-years before CSII therapy to 7.96 events per 100 patient-years while on CSII therapy. The incidence of DKA increased from 1.39 events pre-CSII to 3.98 events per 100 patient-years while on CSII therapy. BMI z-scores showed a nonsignificant increase.

CONCLUSIONS

The long-term use of CSII in pediatric patients is beneficial in lowering mean HbA(1c) levels and the number of SH events. However, there was an increase in the number of DKA episodes.