Analysis of insulin pump settings in children and adolescents with type 1 diabetes mellitus

Advanced decision support system for individuals with diabetes on multiple daily injections therapy using reinforcement learning and nearest-neighbors: In-silico and clinical results

Many individuals with diabetes on multiple daily insulin injections therapy use carbohydrate ratios (CRs) and correction factors (CFs) to determine mealtime and correction insulin boluses. The CRs and CFs vary over time due to physiological changes in individuals' response to insulin. Errors in insulin dosing can lead to life-threatening abnormal glucose levels, increasing the risk of retinopathy, neuropathy, and nephropathy. Here, we present a novel learning algorithm that uses Q-learning to track optimal CRs and uses nearest-neighbors based Q-learning to track optimal CFs. The learning algorithm was compared with the run-to-run algorithm A and the run-to-run algorithm B, both proposed in the literature, over an 8-week period using a validated simulator with a realistic scenario created with suboptimal CRs and CFs values, carbohydrate counting errors, and random meals sizes at random ingestion times. From Week 1 to Week 8, the learning algorithm increased the percentage of time spent in target glucose range (4.0 to 10.0 mmol/L) from 51 % to 64 % compared to 61 % and 58 % with the run-to-run algorithm A and the run-to-run algorithm B, respectively. The learning algorithm decreased the percentage of time spent below 4.0 mmol/L from 9 % to 1.9 % compared to 3.4 % and 2.3 % with the run-to-run algorithm A and the run-to-run algorithm B, respectively. The algorithm was also assessed by comparing its recommendations with (i) the endocrinologist's recommendations on two type 1 diabetes individuals over a 16-week period and (ii) real-world individuals' therapy settings changes of 23 individuals (19 type 2 and 4 type 1) over an 8-week period using the commercial Bigfoot Unity Diabetes Management System. The full agreements (i) were 89 % and 76 % for CRs and CFs for the type 1 diabetes individuals and (ii) was 62 % for mealtime doses for the individuals on the commercial Bigfoot system. Therefore, the proposed algorithm has the potential to improve glucose control in individuals with type 1 and type 2 diabetes.

Safety and Glycemic Outcomes During the MiniMedTM Advanced Hybrid Closed-Loop System Pivotal Trial in Children and Adolescents with Type 1 Diabetes

Background: During MiniMed™ advanced hybrid closed-loop (AHCL) use by adolescents and adults in the pivotal trial, glycated hemoglobin (A1C) was significantly reduced, time spent in range (TIR) was significantly increased, and there were no episodes of severe hypoglycemia or diabetic ketoacidosis (DKA). The present study investigated the same primary safety and effectiveness endpoints during AHCL use by a younger cohort with type 1 diabetes (T1D). Methods: An intention-to-treat population (N = 160, aged 7-17 years) with T1D was enrolled in a single-arm study at 13 investigational centers. There was a run-in period (∼25 days) using HCL or sensor-augmented pump with/without predictive low-glucose management, followed by a 3-month study period with AHCL activated at two glucose targets (GTs; 100 and 120 mg/dL) for ∼45 days each. The mean ± standard deviation values of A1C, TIR, mean sensor glucose (SG), coefficient of variation (CV) of SG, time at SG ranges, and insulin delivered between run-in and study were analyzed (Wilcoxon signed-rank test or t-test). Results: Compared with baseline, AHCL use was associated with reduced A1C from 7.9 ± 0.9% (N = 160) to 7.4 ± 0.7% (N = 136) (P < 0.001) and overall TIR increased from the run-in 59.4 ± 11.8% to 70.3 ± 6.5% by end of study (P < 0.001), without change in CV, time spent below range (TBR) <70 mg/dL, or TBR <54 mg/dL. Relative to longer active insulin time (AIT) settings (N = 52), an AIT of 2 h (N = 19) with the 100 mg/dL GT increased mean TIR to 73.4%, reduced TBR <70 mg/dL from 3.5% to 2.2%, and reduced time spent above range (TAR) >180 mg/dL from 28.7% to 24.4%. During AHCL use, there was no severe hypoglycemia or DKA. Conclusions: In children and adolescents with T1D, MiniMed AHCL system use was safe, A1C was lower, and TIR was increased. The lowest GT and shortest AIT were associated with the highest TIR and lowest TBR and TAR, all of which met consensus-recommended glycemic targets. ClinicalTrials.gov ID: NCT03959423.

Status and related factors of anxiety of primary caregivers of children with type 1 diabetes: a prospective study

Primary caregivers of children with type 1 diabetes mellitus (T1DM) are prone to negative emotions. This study explored the anxiety status of the caregivers and analyzed the related factors. In this prospective study, 245 primary caregivers of T1DM children who were reexamined in the outpatient clinic of Children's Hospital affiliated to Zhengzhou University between April 2020 and Sep 2022 were surveyed with a questionnaire and the Hamilton Anxiety Rating Scale (HAMA). The detection rate of anxiety symptoms in T1DM primary caregivers was 21.2%, with a total score of HAMA score of 11.74 ± 2.50. There were significant differences between the anxiety and non-anxiety groups in treatment method, HbA1C to standard (≤7.0%), severe hypoglycemia in the last 1 year and the number of adolescent cases (χ2 = 15.798, p = 0.000; χ2 = 4.197, p = 0.040; χ2 = 5.291, p = 0.021; χ2 = 14.279, p = 0.000). Multivariable logistic regression analysis showed that insulin pump treatment, HbA1C to standard (≤7.0%) and adolescence were associated with anxiety in primary caregivers (OR = 4.040, 95%CI 1.969-8.289, p = 0.000; OR = 0.472, 95%CI 0.237-0.955, p = 0.037; OR = 2.952, 95%CI 1.495-5.831, p = 0.002). Pediatric endocrine care should pay more attention to the anxiety of the caregivers of adolescent T1DM children treated with insulin pumps while helping the children manage their disease.

Use of continuous subcutaneous insulin infusion in children and adolescents with type 1 diabetes mellitus: a systematic mapping review

BACKGROUND

Among the treatments for type 1 diabetes mellitus (T1DM), Continuous Subcutaneous Insulin Infusion (CSII) is a device that infuses insulin through the subcutaneous tissue in an uninterrupted manner and that comes closest to the physiological secretion of insulin. The use of CSII can provide the family with greater security and children and adolescents have more autonomy in relation to the treatment of T1DM. There is a lack of reviews that systematically gather the mounting evidence about the use of CSII in children and adolescents with T1DM. Therefore, the aim of this review was to group and describe primary and secondary studies on the use of CSII in children and adolescents with T1DM.

METHODS

A systematic mapping review was performed based on searches in the following databases: PubMed, Embase, CINAHL, Lilacs and PsycINFO, using a combination of descriptors and keywords. The screening of the studies was carried out with the aid of the Rayyan software and reading in full was conducted independently by two reviewers. The data extraction of the studies was performed using an extraction tool adapted and validated by researchers specialized in diabetes. The data were analyzed according to the content analysis technique. The map from geocoding of the studies was produced using the ArcGis 10.5 software.

RESULTS

A total of 113 studies were included in the review, including primary studies, literature reviews and gray literature publications. The content analysis of the results of the studies allowed for the identification of four categories: 1) metabolic control; 2) support networks; 3) benefits of using CSII; and 4) challenges of using CSII, each category having its respective subcategories. The review also made it possible to conduct a rigorous mapping of the literature on the use of CSII considering the location of development and the design of the studies.

CONCLUSIONS

The use of CSII should be indicated by health professionals able to prepare children, adolescents, and their families for the treatment of T1DM, and, despite being a technological device, it may not be suitable for the entire pediatric population.

Diurnal Variation of Real-Life Insulin Sensitivity Factor Among Children and Adolescents With Type 1 Diabetes Using Ultra-Long-Acting Basal Insulin Analogs

BACKGROUND

Estimation of insulin sensitivity factor (ISF) is essential for correction insulin doses calculation. This study aimed to assess real-life ISF among children and adolescents with type 1 diabetes using ultra-long-acting basal insulin analogs and to detect factors associated with ISF among those patients.

METHODS

This prospective observational study was conducted at Sohag University Hospital, Egypt, and included 93 participants aged 6-18 years, diagnosed with T1DM for at least 1 year and using insulin glargine 300 Units/mL or insulin degludec 100 Units/mL as basal insulin. The ISF, insulin-to-carbohydrate ratio (ICR) and insulin doses were initially assessed then adjusted as required. The participants were regularly contacted throughout the follow-up period. Glycemic control parameters were assessed after 3 months.

RESULTS

The ISF showed diurnal variation with higher correction dose requirements for the morning than for the rest of the day (p < 0.001). This pattern of diurnal variation was found in participants with different pubertal stages and in participants using either type of ultra-long acting basal insulin analogs. There was no significant difference between the ISF calculated according to the 1800 rule [1800/Total daily insulin dose (TDD)] and the morning ISF (p = 0.25). The 1800 rule-calculated ISF was significantly lower than the actual ISF for the afternoon (p < 0.001) and the evening (p < 0.001). ISF at different times of the day were significantly correlated with age, body mass index, pubertal stage, diabetes duration, TDD, and ICR. Multiple regression analysis revealed that ICR was the most significant factor associated with ISF. Linear regression analysis revealed that the ISF (in mg/dL) for any time of the day could be estimated as 5.14 × ICR for the same time of the day (coefficient = 5.14, 95% confidence interval: 5.10-5.19, R ² = 0.95, p < 0.001).

CONCLUSION

Diurnal variation of ISF that had to be considered for proper calculation of correction doses. This diurnal variation was found in children and adolescents with different pubertal stages. The 1800 rule was appropriate for the morning correction doses but not in the afternoon or the evening. The TDD and the ICR could be used for ISF estimation.

State of the science: A scoping review and gap analysis of adolescent insulin pump self-management

PURPOSE

Adolescent diabetes outcomes remain poor despite increased use of diabetes technologies such as insulin pump therapy. Meaningful research examining adolescent insulin pump self-management has been done, however, a summary of these self-management findings has not been published. The aim of this literature review is to map, evaluate, and summarize existing adolescent insulin pump self-management research.

METHOD

A scoping review of three databases was conducted to comprehensively report and synthesize relevant literature published before September 2019.

RESULTS

Of the 1295 titles identified, 18 articles met the inclusion criteria and were included in this scoping review. Key insulin pump self-management behaviors were featured in the literature, most notably self-monitoring of blood glucose (SMBG) and bolus frequency. Several factors were found to influence pump self-management including psychological factors, parental support and self-management transition, insulin pump education and knowledge acquisition, and environmental factors. We uncovered five gaps in the literature including: an unclear delineation of adolescent age; limited minority representation; variability in the definitions and reporting of self-management behaviors; the role of data sharing and remote monitoring was not addressed; and there remains limited inquiry into diabetes burden and distress associated with insulin pump self-management.

PRACTICE IMPLICATIONS

There exists a consensus that well-established behaviors, such as bolus and SMBG frequency, influence glycemic outcomes for adolescent insulin pump users, however, full insulin pump utilization and self-management is poorly understood. Diabetes clinicians should work to support adolescent insulin pump self-management practices by reinforcing bedrock behaviors while fostering supportive factors found to influence pump self-management.

A Digital Health Intervention (SweetGoals) for Young Adults With Type 1 Diabetes: Protocol for a Factorial Randomized Trial

BACKGROUND

Many young adults with type 1 diabetes (T1D) struggle with the complex daily demands of adherence to their medical regimen and fail to achieve target range glycemic control. Few interventions, however, have been developed specifically for this age group.

OBJECTIVE

In this randomized trial, we will provide a mobile app (SweetGoals) to all participants as a "core" intervention. The app prompts participants to upload data from their diabetes devices weekly to a device-agnostic uploader (Glooko), automatically retrieves uploaded data, assesses daily and weekly self-management goals, and generates feedback messages about goal attainment. Further, the trial will test two unique intervention components: (1) incentives to promote consistent daily adherence to goals, and (2) web health coaching to teach effective problem solving focused on personalized barriers to self-management. We will use a novel digital direct-to-patient recruitment method and intervention delivery model that transcends the clinic.

METHODS

A 2x2 factorial randomized trial will be conducted with 300 young adults ages 19-25 with type 1 diabetes and (Hb)A_1c ≥ 8.0%. All participants will receive the SweetGoals app that tracks and provides feedback about two adherence targets: (a) daily glucose monitoring; and (b) mealtime behaviors. Participants will be randomized to the factorial combination of incentives and health coaching. The intervention will last 6 months. The primary outcome will be reduction in A_1c. Secondary outcomes include self-regulation mechanisms in longitudinal mediation models and engagement metrics as a predictor of outcomes. Participants will complete 6- and 12-month follow-up assessments. We hypothesize greater sustained A_1c improvements in participants who receive coaching and who receive incentives compared to those who do not receive those components.

RESULTS

Data collection is expected to be complete by February 2025. Analyses of primary and secondary outcomes are expected by December 2025.

CONCLUSIONS

Successful completion of these aims will support dissemination and effectiveness studies of this intervention that seeks to improve glycemic control in this high-risk and understudied population of young adults with T1D.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04646473; https://clinicaltrials.gov/ct2/show/NCT04646473.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/27109.

Self-management among pre-teen and adolescent diabetes device users

OBJECTIVE

Despite increased diabetes device use, few adolescents with type 1 diabetes (T1D) meet glycemic targets. We examine associations between utilization of insulin pumps and continuous glucose monitoring (CGM) and glycemic control.

RESEARCH DESIGN AND METHODS

This prospective cohort study included 80 youths (10-18 years of age) with T1D. Multiple linear regression and linear mixed models (LMM) were used to estimate the effects of device self-management on HbA1c and daily time in range (70-180 mg/dL), respectively.

RESULTS

Every blood glucose (BG) input/day was associated with a 0.2% decrease in HbA1c (95% CI: -0.297, -0.013), each bolus/day was associated with a 0.2% decrease (-0.327, -0.057), and use of CGM was associated with a 0.5% decrease (-1.00, -0.075). Among CGM users (n = 45) every 10% increase in CGM use was associated with a 0.3% decrease in HbA1c (-0.390, -0.180). In LMM accounting for within subject and between subject variability, there was a negative association between BG input/day frequency (coefficient = -1.880, [-2.640, -1.117]) and time in range. Residual random effects for CGM users were large showing time in range varied between youth with a SD of 15.0% (3 hours and 36 minutes) (SE 2.029, [11.484, 19.530]). Time in range varied significantly from day-to-day with SD of 18.6% (4 hours and 40 minutes) (SE0.455, [17.690, 19.473]).

CONCLUSIONS

Device self-management behaviors among youth are significantly associated with both HbA1c and time in range. Our findings showing an association between reduced time in range and increased self-management behaviors is novel and deserves further investigation.

Online Glucose Prediction Using Computationally Efficient Sparse Kernel Filtering Algorithms in Type-1 Diabetes

Streaming data from continuous glucose monitoring (CGM) systems enable the recursive identification of models to improve estimation accuracy for effective predictive glycemic control in patients with type-1 diabetes. A drawback of conventional recursive identification techniques is the increase in computational requirements, which is a concern for online and real-time applications such as the artificial pancreas systems implemented on handheld devices and smartphones where computational resources and memory are limited. To improve predictions in such computationally constrained hardware settings, efficient adaptive kernel filtering algorithms are developed in this paper to characterize the nonlinear glycemic variability by employing a sparsification criterion based on the information theory to reduce the computation time and complexity of the kernel filters without adversely deteriorating the predictive performance. Furthermore, the adaptive kernel filtering algorithms are designed to be insensitive to abnormal CGM measurements, thus compensating for measurement noise and disturbances. As such, the sparsification-based real-time model update framework can adapt the prediction models to accurately characterize the time-varying and nonlinear dynamics of glycemic measurements. The proposed recursive kernel filtering algorithms leveraging sparsity for improved computational efficiency are applied to both in-silico and clinical subjects, and the results demonstrate the effectiveness of the proposed methods.

Prospective evaluation of insulin-to-carbohydrate ratio in children and adolescents with type 1 diabetes using multiple daily injection therapy

AIM

Assessment of insulin-to-carbohydrate ratio (ICR) in children and adolescents with type 1 diabetes mellitus (T1DM) using multiple daily injection (MDI) therapy.

METHODS

This prospective observational study was conducted over a 2-year period at Sohag University Hospital, Egypt. Children and adolescents aged 4 to 17 years, diagnosed with T1DM for at least 1 year, with fasting serum C-peptide levels <0.24 ng/dL and whose parents accepted to shift their management to flexible MDI using carbohydrate counting, were included. Participants were initially hospitalized for estimation of ICR and insulin doses, then followed-up monthly for further adjustments. Insulin doses, ICR, and glycemic control parameters were assessed after 3 months.

RESULTS

The study included 201 participants, 110 (54.7%) of them were males. The median age was 9.5 years (interquartile range: 7-12.5 years). Bolus insulin requirements estimated by the 500 rule were significantly lower than the actual doses used by the study participants for all meals (P < .001). Bolus insulin requirement for morning meal was significantly higher compared to other meals (P < .001). Linear regression analyses between ICR for different meals and the reciprocal of total daily dose (TDD) in 96 participants with optimum glycemic control revealed that ICR could be calculated as 301 to 309/TDD for morning meal (R² = 0.97, P < .001), 317 to 331/TDD for afternoon meal (R² = 0.96, P < .001), and 362 to 376/TDD for evening meal (R² = 0.98, P < .001).

CONCLUSIONS

Bolus insulin requirements showed diurnal variation. Using 301 to 309/TDD, 317 to 331/TDD, and 362 to 376/TDD formulas would be more appropriate than the 500 rule for initial estimation of ICR for morning, afternoon, and evening meals, respectively.

Review of a commercially available hybrid closed-loop insulin-delivery system in the treatment of Type 1 diabetes

Type 1 diabetes is an important medical condition causing significant burden and morbidity to those persons affected by it. Improvements in insulin products, insulin delivery and glucose monitoring technology have all contributed to reductions in long-term complications and hypoglycemia. This article reviews the Medtronic 670G device and summarizes the data supporting how this product reduces the burden and increases the safety of insulin dosing in Type 1 diabetes.

Insulin pump use and discontinuation in children and teens: a population-based cohort study in Ontario, Canada

OBJECTIVE

To describe insulin pump use by youth since introduction of universal funding in Ontario, Canada and to explore the relationship between pump use and pediatric diabetes center characteristics and the relationship between discontinuation and center and patient characteristics.

RESEARCH DESIGN AND METHODS

Observational, population-based cohort study of youth with type 1 diabetes (<19 yr) who received pump funding from 2006 to 2013 (n = 3700). We linked 2012 survey data from 33 pediatric diabetes centers to health administrative databases. We tested the relationship between center-level pump uptake and center characteristics (center type, physician model, and availability of 24-h support) using an adjusted negative binomial model; we studied center- and patient-level factors (socioeconomic status and baseline glycemic control) associated with discontinuation using a Cox proportional hazards model with generalized estimating equations.

RESULTS

Pump users were more likely to be in the highest income quintile than non-pump users (29.6 vs. 19.1%, p < 0.0001). In 2012, mean percent pump use was 38.0% with variability across centers. There was no association between uptake and center characteristics. Discontinuation was low (0.42/100 person-yr) and was associated with being followed at a small community center [hazard ratio (HR): 2.24 (1.05-4.76)] and being more deprived [HR: 2.36 (1.14-1.48)]. Older age was associated with a lower rate of discontinuation [HR: 0.31 (0.14-0.66)].

CONCLUSIONS

Rates of pump use have increased since 2006 and discontinuation is rare. Large variation in uptake across centers was not explained by the factors we examined but may reflect variation in patient populations or practice patterns, and should be further explored.

Continuous Subcutaneous Insulin Infusion in Children: A Pilot Study Validating a Protocol to Avoid Hypoglycemia at Initiation

BACKGROUND

The occurrence of hypoglycemia and hyperglycemia during the first days after transition to continuous subcutaneous insulin infusion (CSII) in patients with type 1 diabetes has not been systematically studied in children. The aim of this prospective study was to demonstrate that the protocol applied in our diabetes clinic is safe at CSII initiation in children.

METHODS

We assessed 22 pediatric patients with type 1 diabetes, using continuous glucose monitoring (CGM) before and after CSII initiation (±3 days).

RESULTS

After CSII initiation, there was no difference in the rates of hypoglycemic events expressed as relative rates (RRs) per person-reading (RR = 0.85, p = 0.52, 95% CI 0.52-1.39), as well as in the number of prolonged hypoglycemic events (>1 h) per day (RR = 1.12, p = 0.56, 95% CI 0.75-1.68). We observed only a trend toward prolonged episodes of hyperglycemia after pump initiation (RR = 1.52, p = 0.06, 95% CI 0.97-2.35).

CONCLUSION

Our study is the first to assess, through CGM and in a prospective way, the impact of a CSII initiation protocol on glycemic values. Our protocol provides a safe model to avoid hypoglycemia at CSII initiation in children.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov, identifier NCT01840358.

Optimum bolus wizard settings in insulin pumps in children with Type 1 diabetes

AIM

To evaluate current insulin pump settings in an optimally regulated paediatric population using bolus wizard.

METHODS

We used a retrospective study design to analyse data from 124 children on insulin pump therapy who had optimum HbA1c levels [< 59 mmol/mol (< 7.5%)] and no history of severe hypoglycaemic events. Bolus wizard settings were used to calculate the insulin to carbohydrate factors and insulin sensitivity factors. Multiple regression analysis was used to analyse the variables associated with the calculation factors.

RESULTS

Insulin to carbohydrate factor varied from 276 in the youngest group to 424 in the oldest group, and increased according to age. Insulin sensitivity factor was highest in the group aged 6 to < 12 years, with a value of 125. Age, amount of carbohydrates, number of boluses per day and insulin per kg were all significantly associated with both calculation factors. Furthermore, duration of insulin pump treatment was significantly associated with insulin sensitivity factor and percentage bolus/basal was significantly associated with insulin to carbohydrate factor. Gender, diabetes duration and BMI were not associated with any of the calculation factors.

CONCLUSION

Optimum insulin pump settings at pump initiation depend on both insulin requirements and use of the pump. Settings need to be individualized because the standardized calculation factors are not constant for children. There is a need to develop specific age- and insulin dose-dependent calculation factors.