Age-specific characteristics of the basal insulin-rate for pediatric patients on CSII

Expert Recommendations for Using Time-in-Range and Other Continuous Glucose Monitoring Metrics to Achieve Patient-Centered Glycemic Control in People With Diabetes

New metrics for assessing glycemic control beyond HbA1c have recently emerged due to the increasing use of continuous glucose monitoring (CGM) in diabetes clinical practice. Among them, time in range (TIR) has appeared as a simple and intuitive metric that correlates inversely with HbA1c and has also been newly linked to the risk of long-term diabetes complications. The International Consensus on Time in Range established a series of target glucose ranges (TIR, time below range and time above range) and recommendations for time spent within these ranges for different diabetes populations. These parameters should be evaluated together with the ambulatory glucose profile (AGP). Using standardized visual reporting may help people with diabetes and healthcare professionals in the evaluation of glucose control in frequent clinical situations. The objective of the present review is to provide practical insights to quick interpretation of patient-centered metrics based on flash glucose monitoring data, as well as showing some visual examples of common clinical situations and giving practical recommendations for their management.

Patients with Type 1 Diabetes Treated with Insulin Pumps Need Widely Heterogeneous Basal Rate Profiles Ranging from Negligible to Pronounced Diurnal Variability

BACKGROUND

Pump-treated patients with type 1 diabetes have widely differing basal insulin infusion profiles. We analyzed consequences of such heterogeneity for glycemic control under fasting conditions.

METHODS

Data from 339 adult patients with type 1 diabetes on insulin pump therapy undergoing a 24-hour fast (basal rate test) were retrospectively analyzed. Hourly programmed basal insulin infusion rates and plasma glucose concentrations as well as their proportions within, below, or above arbitrarily defined target ranges were assessed for specific periods of the day (eg, 1-7 hours, "dawn" period, 16-19 hours, "dusk" period, reference period 20-1 hours/10-14 hours), by tertiles of a predefined "dawn" index (mean basal insulin infusion rate during the "dawn" divided by the reference periods).

RESULTS

The "dawn" index varied interindividually from 0.7 to 4.4. Basal insulin infusion profiles exhibited substantial differences (P = .011), especially overnight. Despite higher insulin infusion rates at 4 and 6.45 hours, patients with the most pronounced "dawn" phenomenon exhibited higher plasma glucose concentrations at those time points (P < .012). Patients with a marked "dawn" phenomenon exhibited a lower probability for low (<4.4 mmol/L) and a higher probability of high values (>7.2 mmol/L) during the dawn period (all P values <.01).

CONCLUSIONS

We observe substantial interindividual heterogeneity in the "dawn" phenomenon. However, widely different empirically derived basal insulin infusion profiles appear appropriate for individual patients, as indicated by similar plasma glucose concentrations, mainly in the target range, during a 24-hour fasting period.

Initial Basal and Bolus Rates and Basal Rate Variability During Pump Treatment in Children and Adolescents

OBJECTIVE

Pump-treated children with type 1 diabetes (T1DM) have widely differing basal insulin (BI) infusion profiles for specific periods of the day. The pattern of BI requirements depends on the timing and magnitude of cortisol and growth hormone secretion within each age group. In adolescents and young adults, a decreased insulin sensitivity is seen, particularly in the early morning (dawn phenomenon) and to a lesser extent, in the late afternoon (dusk phenomenon). Different approaches exist for the inititation of basal rates. However, there is a lack of evidence-based recommendation, especially in young children. Usually the basal rates are set equally throughout day and night or the day is divided into tertiles. The aim of this study was to analyze the change of the initial, equally distributed, BI rates over the first year of standard insulin pump therapy.

METHODS

A total of 154 patients with T1DM, aged between 0 and <21 years at diagnosis, from a single center were documented. Patients were divided into five age groups according to age at pump initiation: group 1, <5 years (n=36); group 2, 5-8 years (n=20); group 3, 8-15 years (n=74); group 4, 15-18 years, (n=19); and group 5, >18 years, (n=5). Distribution of hourly basal rates at the initiation of the pump and at the end of first year were evaluated.

RESULTS

Median (range) age and diabetes duration was 14.46 (1.91-26.15) and 7.89 (1.16-17.15) years, respectively. Forty-four percent were male, 56% were female. Mean total insulin dose/kg in the whole cohort at the initiation and after one year of pump therapy was 0.86±0.23 U/kg and 0.78±0.19 U/kg, respectively and differed significantly between each age group (p<0.001; p<0.001). Mean daily basal rate/kg showed significant differences between the five groups (p<0.001). Circadian distribution of BI differed markedly among the five age groups.

CONCLUSION

At the initiation of insulin pump therapy, circadian profiles by age group should be taken into account in pediatric patients to optimize basal rate faster and more easily.

Basal insulin requirement in patients with type 1 diabetes depends on the age and body mass index

AIMS/INTRODUCTION

To investigate the basal insulin requirement in patients with type 1 diabetes who are on multiple daily injections (MDI) and to assess the patient characteristics that affect the percent of total daily basal insulin dose to the total daily insulin dose (%TBD/TDD).

MATERIALS AND METHODS

The subjects of this study were 67 inpatients with type 1 diabetes who were served diabetic meals of 25-30 kcal/kg standard body weight during several weeks of hospitalization. The basal insulin requirement was adjusted to keep the blood glucose level from bedtime to before breakfast within a 30 mg/dL difference. The bolus insulin dose before the meal was adjusted to keep the blood glucose level below 140 and 200 mg/dL before and 2 h after each meal, respectively. The total daily insulin dose (TDD), the percent of total daily basal insulin dose (TBD) to TDD (%TBD/TDD), and clinical characteristics were collected.

RESULTS

The median (Q1, Q3) of TDD was 33.0 (26.0, 49.0) units, and the %TBD/TDD was 24.1 ± 9.8%. The %TBD/TDD was positively correlated with the body mass index (BMI) and negatively correlated with the age at the onset and at the examination according to a univariate analysis. However, the %TBD/TDD was dependent on the BMI (β = 0.340, P = 0.004) and the age at examination (β = -0.288, P = 0.012) according to the multiple regression analysis.

CONCLUSIONS

The average %TBD/TDD in patients with type 1 diabetes on MDI was approximately 24% under inpatient conditions. The basal insulin requirement was dependent on the BMI and the age at examination.

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.

Clinical Approach to Flash Glucose Monitoring: An Expert Recommendation

The flash glucose monitoring (FGM) system FreeStyle Libre® is a device that measures interstitial glucose in a very simple way and indicates direction and speed of glucose change. This allows persons with diabetes to prevent hypoglycemic and hyperglycemic events. Scientific evidence indicates that the system can improve glycemic control and quality of life. To obtain the maximum benefit, it is necessary to properly handle glucose values and trends. Due to the generalization of the system use, the purpose of the document is to provide recommendations for the optimal use of the device, not only in the management of glucose values and trends but also in the prevention of hypoglycemia, actuation in exercise, special situations, and retrospective analysis of the glucose data, among others.

Distinct Patterns of Daily Glucose Variability by Pubertal Status in Youth With Type 1 Diabetes

OBJECTIVE

To evaluate glycemia and metrics of glucose variability in youth with type 1 diabetes, and to assess patterns of 24-h glucose variability according to pubertal status.

RESEARCH DESIGN AND METHODS

Metrics of glycemia, glucose variability, and glucose patterns were assessed by using 4 weeks of continuous glucose monitoring (CGM) data from 107 youth aged 8-17 years with type 1 diabetes for ≥1 year. Glucose values per hour were expressed as percentages relative to the mean glucose over 24 h for a 4-week period. Glucose data were compared on the basis of pubertal status-prepubertal (Tanner stage [T] 1), pubertal (T2-4), and postpubertal (T5)-and A1C categories (<7.5% [<58 mmol/mol], ≥7.5% [≥58 mmol/mol]).

RESULTS

Youth (50% female, 95% white) had a mean ± SD age of 13.1 ± 2.6 years, diabetes duration of 6.3 ± 3.5 years, and A1C of 7.8 ± 0.8% (62 ± 9 mmol/mol); 88% were pump treated. Prepubertal youth had a higher mean glucose SD (86 ± 12 mg/dL [4.8 ± 0.7 mmol/L]; P = 0.01) and coefficient of variation (CV) (43 ± 5%; P = 0.06) than did pubertal (SD 79 ± 13 mg/dL [4.4 ± 0.7 mmol/L]; CV 41 ± 5%) and postpubertal (SD 77 ± 14 mg/dL [4.3 ± 0.8 mmol/L]; CV 40 ± 5%) youth. Over 24 h, prepubertal youth had the largest excursions from mean glucose and the highest CV across most hours compared with pubertal and postpubertal youth. Across all youth, CV was strongly correlated with the percentage of time with glucose <70 mg/dL (<3.9 mmol/L) (r = 0.79; P < 0.0001).

CONCLUSIONS

Prepubertal youth had greater glucose variability independent of A1C than did pubertal and postpubertal youth. A1C alone does not capture the full range of glycemic parameters, highlighting the added insight of CGM in managing youth with type 1 diabetes.

Proportion of Basal to Total Insulin Dose Is Associated with Metabolic Control, Body Mass Index, and Treatment Modality in Children with Type 1 Diabetes-A Cross-Sectional Study with Data from the International SWEET Registry

OBJECTIVES

To investigate in a large population the proportion of daily basal insulin dose (BD) to daily total insulin dose (TD) (BD/TD) and its association with glycated hemoglobin A1c (HbA1c), body mass index (BMI)- SDS, and treatment modality in children with type 1 diabetes.

STUDY DESIGN

Cross-sectional study in subjects with type 1 diabetes, age ≤18 years, and ≥2 years of diabetes duration, registered in the international multicenter Better control in Pediatric and Adolescent diabeteS: Working to crEate CEnTers of Reference registry in March 2018. Variables included region, sex, age, diabetes duration, treatment modality (multiple daily injections [MDI] or continuous subcutaneous insulin infusion [CSII]), self-monitoring blood glucose, HbA1c, BD/TD, and BMI-SDS. BMI was converted to BMI-SDS using World Health Organization charts as reference. Hierarchic linear regression models were applied with adjustment for age, sex, and diabetes duration.

RESULTS

A total of 19 687 children with type 1 diabetes (49% female, 49% CSII users) with median age 14.8 (11.5; 17.2) years and diabetes duration 6.0 (3.9; 9.0) years were included. HbA1c was 63 (55; 74) mmol/mol (7.9 [7.2; 8.9]%), and BMI-SDS 0.55 (-0.13; 1.21). Unadjusted, a lower BD/TD was associated with lower HbA1c, male sex, younger age, shorter diabetes duration, lower BMI-SDS, higher numbers of self-monitoring blood glucose and CSII (all P < .01). After adjustment for confounders, lower BD/TD was associated with lower HbA1c (P < .01) and lower BMI-SDS (P < .01) in children on CSII, but not on MDI.

CONCLUSIONS

Lower BD/TD is positively associated with lower HbA1c and lower BMI-SDS in children with type 1 diabetes on CSII. It remains to be investigated in a prospective study whether reducing BD/TD insulin will improve metabolic control and normalize body weight in children with type 1 diabetes.

Model-Based Tool for Personalized Adjustment of Basal Insulin Supply in Patients With Intensified Conventional Insulin Therapy

BACKGROUND

The decisive factor in successful intensive insulin therapy is the ability to deliver need-based-adjusted nutrition-independent insulin dosages at the closest possible approximation to the physiological insulin level. Because this basal insulin requirement is strongly influenced by the patient's lifestyle, its subtlety is of great importance. This challenge is very different between patients with type 1 diabetes and those with insulin-dependent type 2 diabetes. Furthermore, it is more difficult to finetune a basal insulin dosage with intensified conventional insulin therapy (ICT), due to delayed insulin delivery, compared to insulin pump therapy, which provides continuous delivery of small doses of exclusively short-acting insulin. In all cases, the goal is to achieve an optimal basal delivery rate.

METHOD

We hypothesized that this goal could be achieved with a modeling tool that determined the optimal basal insulin supply based on the patient's anamnestic data and monitored glucose values. This type of modeling tool has been used in health insurance programs in Germany to improve insulin control in patients that receive ICT.

RESULTS

Our retrospective data analysis showed that this modeling tool provided a significant improvement in metabolic control, significant reductions in HbA1c and Q scores, and improved time-in-range values, with reduced daily insulin levels.

CONCLUSION

The model-based basal rate test could provide additional data of the actual effect of the basal insulin adjustment in intensified insulin treated diabetes to the physician or treatment team.

Determination of Pubertal Status in Youths With Type 1 Diabetes Using Height Velocity and Trajectories

CONTEXT

Assessment of pubertal change is important for the management of chronic pediatric diseases, such as type 1 diabetes. Physical and/or laboratory assessments of pubertal status are often unavailable, impractical, or costly.

OBJECTIVE

To develop and validate a practical and objective method to assess pubertal status using longitudinal linear growth in youths with type 1 diabetes.

DESIGN, PARTICIPANTS, AND OUTCOME MEASUREMENTS

Participants (n = 123) were part of a 2-year study assessing continuous glucose monitoring in youths with type 1 diabetes at a tertiary diabetes center. Pubertal status at visits was assigned by a tiered approach using clinical Tanner staging or indicators of pubertal maturation from the electronic medical record when available. For other visits, independent evaluations of height velocities and growth chart trajectories provided data for pubertal status assignments. Sensitivity analysis confirmed the validity of the pubertal status assignments.

RESULTS

The sample (50% female, 95% white) had a mean ± SD age of 12.7 ± 2.7 years, diabetes duration of 6.0 ± 3.6 years, and hemoglobin A1c of 7.9 ± 0.8%. Of 985 study visits, 50% received a pubertal status assignment based on clinical Tanner staging, 29% on additional medical record review, and 22% on an evaluation of height velocity and growth chart trajectory. For the sensitivity analysis, pubertal status assignments based on height velocity and growth chart trajectory matched clinical Tanner staging in 87% of visits.

CONCLUSIONS

Our practical and objective method to assess pubertal status based on height velocity and growth chart trajectory highlights growth as a reliable and objective bioassay for pubertal onset, status, and progression.

The influence of patient variables on insulin total daily dose in paediatric inpatients with new onset type 1 diabetes mellitus

PURPOSE

Insulin dose requirements at new diagnosis of type 1 diabetes mellitus (T1DM) vary widely. Current guidelines recommend an initial total daily dose (TDD) ranging from 0.5 to 1.0 IU/kg/day. It often takes several days of frequent dose adjustments before an optimal insulin dose is achieved. The aim of this study was to identify the influence of patient variables on the dose-requirement of insulin in newly diagnosed children with T1DM.

METHODS

A retrospective chart review of children (≤ 18 years old) admitted to hospital between 2010 and 2016 due to new onset T1DM was undertaken. Demographic, clinical, insulin dosing, and laboratory data were recorded. The influence of patient characteristics on insulin TDD was analysed statistically by performing univariate and multivariate linear regression analyses.

RESULTS

Complete clinical records for 70 patients were available for analysis. The median insulin TDD on first day of admission was 21 (4.5 to 75 units) and that on the day before discharge was 27 (5.5 to 124 units). In the multivariate regression analysis, body size (total body weight and fat-free mass), glycated haemoglobin (HbA1C), and blood ketone concentration were found to be significant predictors of optimal insulin TDD (p < 0.05).

CONCLUSION

In addition to body size, HbA1c and ketone concentrations are useful in calculating initial TDD in newly diagnosed children with T1DM. This could potentially decrease the number of days needed to reach a stable dose and result in improved early glycaemic control.

Continuous Subcutaneous Insulin Infusion Characteristics in Type 1 Diabetes Children and Adolescents in Qatar

AIM

To describe continuous subcutaneous insulin infusion (CSII) characteristics in type 1 diabetes mellitus (T1DM) children and adolescents using a standardized protocol in routine clinical settings in Qatar.

METHODS

A total of 138 T1DM patients (62 males; 76 females; mean age 9.8 ± 3.4 years) with a mean diabetes duration of 2.4 ± 1.9 years initiated CSII (MiniMed^® Veo^®™ and MiniMed^® 640 G insulin pumps; Medtronic, Northridge, CA, USA) in 2016 and 2017. CSII characteristics and glycated hemoglobin (HbA1c) were evaluated 1 year after treatment initiation.

RESULTS

At 1 year after treatment initiation, the insulin dose had significantly increased (from 0.59 ± 0.23 to 0.74 ± 0.26 U/kg body weight per 24; P < 0.05), and the HbA1c level had significantly decreased (from 9.7 ± 1.3 to 8.1 ± 0.6%; P < 0.05). More than 92% of patients used the Bolus Wizard feature of the insulin pump at the following settings: insulin-to-carbohydrate ratio 19.2 ± 9.3 g; insulin sensitivity factor 131 ± 68 mg/dl; target range 91 ± 9.3-135 ± 14.2 mg/dl; active insulin time 3.8 ± 0.8 h.

CONCLUSION

Our results show that CSII may significantly improve glucose control in T1D children and adolescents who use a standardized protocol. A reduction of HbA1c by - 1.6% was achieved at 1 year after CSII initiation. These results need to be confirmed in a study with a longer duration.

Pharmacotherapy of type1 diabetes in children and adolescents: more than insulin?

For paediatric patients with type 1 diabetes, intensified insulin therapy with either multiple daily injection or insulin pump therapy is currently the only method of treatment. To optimize this therapy, insulin analogues are fixed parts of all therapy regimens. New ultra-rapid insulins seem to be beneficial not only in adults but also in this age group. New developments in long-acting analogues have demonstrated safety and will be regular in paediatrics, we hope, soon. Furthermore, the psychosocial approach for consideration of real-life aspects becomes more the focus of therapeutic regimens and is implemented into international guidelines. Technical improvements, such as continuous glucose monitoring, particularly in combination with pump therapy, support the great success of rapid-acting analogues by reducing hypoglycaemias. Non-insulin agents such as SGLT2-inhibitors show beneficial aspects in people with type 1 diabetes. For outpatient care with these currently off-label-used drugs, special training for measurement of ketones should be imperative.

Basal Insulin Dose in Adults with Type 1 Diabetes Mellitus on Insulin Pumps in Real-Life Clinical Practice: A Single-Center Experience

INTRODUCTION

Basal insulin (BI) infusion in pump therapy of type 1 diabetes (T1DM) mimics physiological secretion during the night and between meals. The recommended percentage of the total BI to daily insulin dose (termed the %BI) ranges between 30 and 50%. We analyzed whether this recommendation was followed in adults with T1DM from a university center, and whether BI doses were linked with glycemic control.

MATERIALS AND METHODS

We included 260 consecutive patients with T1DM (159 women and 101 men) treated with continuous subcutaneous insulin infusion at the Department of Metabolic Diseases, Krakow, Poland. Data were downloaded from patients' pumps and collected from medical records. We analyzed the settings of BI and the association of %BI with HbA1c level. Linear regression was performed.

RESULTS

The mean age of T1DM individuals was 26.6 ± 8.2 years, BMI was 23.1 ± 3.0 kg/m², T1DM duration was 13.3 ± 6.4 years, and HbA1c level was 7.4%. There were 69.6% (n=181) of T1DM patients with %BI in the recommended range. The T1DM duration and HbA1c level of patients with a %BI <30% (n=23) was 9.5 years and 6.4%, respectively; for a %BI of 30-50%, it was 13.2 years and 7.4%; and for a %BI >50% (n=56), it was 15.8 years and 7.8% (p < 0.001 for both three-group comparisons). Multiple regression identified %BI among independent predictors of the HbA1c level.

CONCLUSION

In this real-life analysis, the recommendations concerning %BI dosing were not followed by almost one-third of adult T1DM patients. Low %BI was associated with better glycemic control; however, this requires further confirmation.

Type 1 Diabetes and Long-Term Continuous Subcutaneous Insulin Infusion Therapy: A 10-Year Experience from Macedonia

BACKGROUND

Subcutaneous insulin infusion (CSII) therapy is a challenge for both patients and healthcare providers. The long-term CSII use is scarce. The aim of this study is to describe the impact of CSII therapy for 10 years of use at our center.

METHODS

This single-center retrospective study includes 162 type 1 diabetes patients using CSII for >3 years during October 2004 until October 2014. Data were collected through the electronic medical record system, cross-sectional analysis (telephone, e-mail, or social media), and CSII reports generated by Carelink Therapy Management Software (Medtronic, Northridge, CA).

RESULTS

Patients were analyzed in three age groups: 12-18, 19-24, and >25 years. All patients were treated with CSII for >3 years. Total daily dose of insulin was >0.9 U/(kg·day) in age group 12-18 years old, which was significantly higher than other two age groups (P < 0.05). Basal ratio was lower in younger age (<40%) and showed trend of increasing with age and longer diabetes duration (up to 44%). Younger patients used bolus wizard on regular basis (>75%), which was significantly higher than other age groups (P < 0.05). More than 50% of patients achieved glycated hemoglobin (HbA1c) <7.0% and >70% of patients achieved HbA1c <7.5%. HbA1c level significantly changed from baseline in all groups (P < 0.05).

CONCLUSION

Our study shows improved glucose control in long-term CSII users. A reduction of HbA1c levels by -1.1% was maintained during the study period.

Basal rate tests (24-hour fasts) performed in type-1 diabetic subjects with either absolute fasting or snacks containing negligible carbohydrate amounts result in similar glucose profiles: A randomized controlled prospective trial

AIMS

Basal rate tests (24-hour fasting periods) may be necessary to optimize basal insulin replacement in type 1 diabetes. It was the aim of this study to prospectively compare the allowance of negligible carbohydrate snacks vs absolute fasting.

METHODS

A total of 20 patients with type 1 diabetes (age, 48 ± 15 years (9 women, 11 men); BMI, 28.5 ± 4.5 kg/m² ; HbA1c, 8.8% ± 2.0% (73.0 ± 21.9 mmol/mol); insulin dose, 0.69 ± 0.31 IU/kg body weight and per day) participated in 2 basal rate tests lasting 24 hours in random order with unchanged basal insulin replacement. On 1 occasion, negligible carbohydrate snacks (salads and vegetables, up to 5.1 g carbohydrate and 276.3 kJ per portion) were allowed; during the second test subjects were obliged to fast absolutely. Plasma glucose profiles were determined using an exact laboratory method. Hypoglycaemic episodes (plasma glucose < 70 mg/dL) were compared.

RESULTS

Plasma glucose concentrations during fasting periods, with and without negligible carbohydrate snacks, did not differ significantly ( P = .65) and differences were negligible (95% confidence intervals always included a difference of 0 mmol/L). Also, there was no difference in the number of hypoglycaemic plasma glucose values (P = .40) or in compensatory carbohydrate intake. Basal rate testing with negligible carbohydrate snacks was better tolerated (questionnaire, P = .046) and the desire to discontinue the fasting period was significantly reduced (P = .023).

CONCLUSIONS

Allowing negligible carbohydrate snacks results in unchanged plasma glucose profiles during basal rate testing and is better tolerated by patients with type 1 diabetes.

Lower dose basal insulin infusion has positive effect on glycaemic control for children with type I diabetes on continuous subcutaneous insulin infusion therapy

OBJECTIVE

The aim of our study was to explore a possible relationship between proportion of basal insulin dose (%BD/T) and glycaemic control in children with type I diabetes on continuous subcutaneous insulin infusion (CSII) therapy.

METHODS

All patients under the age of 18 with type I diabetes mellitus, treated in a general hospital in Utrecht, The Netherlands, who were on CSII therapy between 2000 and 2011 were selected for inclusion. All data as recorded during outpatient visits were retrospectively collected from patients' charts. Analyses were performed using R Statistical Software.

RESULTS

Data of 847 outpatient visits of 78 patients [31 males (39.7%) and 47 females (60.3%)] were analyzed. Mean age at diagnosis was 7.1 ± 3.7 yr, mean age at start of pump therapy 10.1 ± 3.8 yr. Mean HbA1c before pump start was 8.3 ± 1.0%, median BMI standard deviation score for age and gender was 0.64 (-1.89-3.79). Median follow-up time per patient was 29 months with an average of 10 visits (range: 3-25). Multivariate analysis revealed that a change of 10% in %BD/T resulted in a decrease or increase of HbA1c of 0.22% [95% confidence interval (CI): 0.15-0.29). No significant effect was observed from SDS BMI, sex, or duration of diabetes.

CONCLUSION

Low dose basal insulin infusion as a percentage of total insulin dose has a positive effect on metabolic outcome as expressed in HbA1c-levels. A change of 10% in %BD/T results in a decrease or increase of HbA1c of 0.22%. This supports the tendency to aim at the lowest basal insulin requirements in pump setting strategy.

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.

Continuous Subcutaneous Insulin Infusion in Neonates and Infants Below 1 Year: Analysis of Initial Bolus and Basal Rate Based on the Experiences from the German Working Group for Pediatric Pump Treatment

BACKGROUND

Diabetes mellitus is rare in young infants and neonates. Continuous subcutaneous insulin infusion (CSII) is used most frequently for insulin treatment in this age group. However, the individual doctor's experience is scarce because of the low prevalence of diabetes in this age. For this study patients treated with CSII with an age below 1 year were selected from the German/Austrian DPV (Diabetes-Patienten-Verlaufsdokumentation) database, and basal rate and bolus calculation were described.

MATERIALS AND METHODS

For all patients less than 1 year of age, basal rate and mealtime boluses were compared among infants with type 1 diabetes mellitus (T1DM), infants with neonatal diabetes mellitus (NDM), and infants with antibody status unknown diabetes mellitus (AUDM).

RESULTS

Fifty-eight patients with T1DM, 67 neonates with NDM, and 43 infants with early diabetes development after 6 months and negative β-cell antibodies (AUDM) could be analyzed. T1DM patients at onset required a median total insulin amount of 0.83 IU/kg of body weight, whereas NDM patients required 0.74 IU/kg of body weight (P = 0.63). Basal insulin requirement however, was different between the two groups (0.56 IU/kg of body weight in NDM vs. 0.43 IU/kg in T1DM) (P = 0.036). The percentage basal profile of NDM and T1DM patients was quite similar to children at the age of 1-5 years. The proportion of prandial insulin at onset was significantly different (32% in NDM vs. 53% in T1DM) (P < 0.00001). AUDM patients showed almost similar data to T1DM patients. The pattern of mealtime bolus insulin was not different among the groups.

CONCLUSIONS

The presented data can be used as an initial guide value to start CSII treatment in neonates and infants. To be on the safe side we recommend the lower quartile for the dosage as the starting value in nonketotic patients.

Polymorphic basal rates of continuous subcutaneous insulin infusion among Taiwanese children with type 1 diabetes

Introduction. The basal dose of insulin, proportion of total daily insulin, and circadian variation during continuous subcutaneous insulin infusion (CSII) therapy among children with type 1 diabetes mellitus (T1D) have not been fully elucidated. Materials and Methods. A total of 45 childhood patients with T1D receiving CSII therapy at Pediatrics Department of Chang Gung Memorial Hospital between 2004 and 2012 were analyzed. Patients were classified according to Tanner stage. Results. HbA1c was significantly reduced in all Tanner groups within three months of CSII therapy (from 67 mmol/mol (8.3%) to 54 mmol/mol (7.1%), P < 0.05). The actual basal proportion of total daily insulin use was 34–40%. The circadian distribution of basal insulin differed markedly between the five Tanner groups. Basal insulin requirement was highest between 3:00 and 7:00 h in Tanner stages 1-2. In stages 3-4, a lower nocturnal basal insulin that increased gradually until daytime was noted. Adolescents (stage 5) displayed a high insulin peak between 6:00 and 11:00 h, and a smaller peak between 19:00 and 23:00 h. Conclusions. A smaller proportion of basal insulin to total daily insulin use, as well as varied circadian patterns of insulin use, characterized these children with T1D.

Basal and bolus insulin requirements in children, adolescents, and young adults with type 1 diabetes mellitus on continuous subcutaneous insulin infusion (CSII): effects of age and puberty

OBJECTIVE

Guidelines for insulin dosing, including the insulin to carbohydrate ratio (I/C), insulin sensitivity factor (ISF), and basal/bolus ratio guidelines, have been well established for adults with type 1 diabetes mellitus (T1DM). However, clinical experience suggests that these guidelines are not appropriate for children. The purpose of this study was to determine the continuous subcutaneous insulin infusion (CSII) settings in children with T1DM at different ages and stages of puberty.

METHODS

A total of 154 patients data between the ages of 3 and 21 years with well-controlled T1DM according to American Diabetes Association guidelines were reviewed. Only patients on CSII who were not in the honeymoon period were included.

RESULTS

Patients were divided into 8 groups according to age, gender, and/or pubertal stage. Insulin requirements increased with puberty in both sexes (0.69, 0.97, and 0.90 U/kg/day in children <7 years of age, midpubertal girls, and late-pubertal boys, respectively). Basal insulin requirement was lowest in the youngest group (34%; P<.01). The youngest group had the lowest I/C prediction factor (PF) (mean, 315.7 ± 79.4; P<.01 with all groups), and the ISF-PF was higher than that of the oldest group (mean, 2,588.3 ± 1,101.8; P<.01).

CONCLUSION

CSII dose calculations vary with age and pubertal status in children with T1DM. These differences must be considered when calculating CSII dosing, especially for younger children.

Changes in Insulin Requirements From the Onset of Continuous Subcutaneous Insulin Infusion (CSII) Until Optimization of Glycemic Control

The aim was to evaluate changes in insulin requirements from onset of continuous subcutaneous insulin infusion (CSII) until glucose optimization in type 1 diabetes and to determine patient characteristics to be considered when CSII is implemented. We retrospectively analyzed 74 type 1 diabetic patients over a follow-up of 5 months after starting CSII. Patients without a decrease in HbA1c levels at the end of follow-up were excluded. We compared total daily doses (TDD), basal/bolus distribution, basal diurnal/nocturnal proportion, number of basal segments, and HbA1c levels in relation to sex, age, body mass index (BMI), diabetes duration, and indication for CSII. At follow-up, HbA1c decreased by 0.75%, TDD decreased by 18%, basal rate was 60% of TDD, and diurnal basal rate was 60% of total basal rate. Insulin requirements were higher in males and in obese patients. Female patients and patients with longer diabetes duration showed a higher percentage of basal insulin. The number of basal segments was 4.9 ± 2.9. Basal requirements were higher in the second half of the nocturnal period. The dawn phenomenon was more relevant in men. Improvements in glycemic control were more marked in younger patients, in patients with higher HbA1c, in patients using more basal segments, and in patients initiating CSII for glucose control before pregnancy. Sex, diabetes duration, and BMI should be considered when initiating CSII. Our findings may help clinicians in clinical decision making regarding CSII therapy.

Basal insulin requirement of youth with type 1 diabetes differs according to age

We investigated the percentage of total basal insulin dose to total daily insulin dose (%TBD) among Japanese youth of different ages with type 1 diabetes. The study enrolled 69 patients with type 1 diabetes who were treated with multiple daily injections of insulin. The participants were divided into the following age groups: group A, 0 to <10 years (n = 18); group B, 10 to <20 years (n = 31) and group C, 20 to <25 years (n = 20). We found no difference in the sex ratio, body mass index, and glycated hemoglobin and 2-h postprandial C-peptide levels among the three groups. Participants assigned to group B had a significantly higher percentage of total daily insulin dose than those in group A and group C (49.7 ± 10.4% vs 38.5 ± 13.7% and 38.3 ± 8.2%, P = 0.0005). In conclusion, the basal insulin requirements of Japanese youth with type 1 diabetes might have an age effect that is associated with puberty.

Predicting the optimal basal insulin infusion pattern in children and adolescents on insulin pumps

OBJECTIVE

We aimed at developing and cross-validating a mathematical prediction model for an optimal basal insulin infusion pattern for children with type 1 diabetes on continuous subcutaneous insulin infusion therapy (CSII).

RESEARCH DESIGN AND METHODS

We used the German/Austrian DPV-Wiss database for quality control and scientific surveys in pediatric diabetology and retrieved all CSII patients <20 years of age (November 2009). A total of 1,248 individuals from our previous study were excluded (dataset 1), resulting in 6,063 CSII patients (dataset 2) (mean age 10.6 ± 4.3 years). Only the most recent basal insulin infusion rates (BRs) were considered. BR patterns were identified and corresponding patients sorted by unsupervised clustering. Logistic regression analysis was applied to calculate the probabilities for each BR pattern. Equations were based on both independent datasets separately, and probabilities for BR patterns were cross-validated using typical test patients.

RESULTS

Of the 6,063 children, 5,903 clustered in one of four major circadian BR patterns, confirming our previous study. The oldest age-group (mean age 12.8 years) was represented by 2,490 patients (42.18%) with a biphasic dawn-dusk pattern (BC). A broad single insulin maximum at 9-10 p.m. (F) was unveiled by 853 patients (14.45%) (mean age 6.3 years). Logistic regression analysis revealed that age, to a lesser extent duration of diabetes, and partly sex predicted BR patterns. Cross-validation revealed almost identical probabilities for BR patterns BC and F in the two datasets but some variation in the remaining two BR patterns.

CONCLUSIONS

Reconfirmation of four key BR patterns in two very large independent cohorts supports that these patterns are realistic approximations of the circadian distribution of insulin needs in children with type 1 diabetes. Prediction of an optimal pattern a priori can improve initiation and clinical follow-up of CSII in children and adolescents. In addition, these BR patterns represent valuable information for insulin-infusion algorithms in closed-loop CSII.

Insulin doses before and one year after pump start: children have a reversed dawn phenomenon

OBJECTIVE

We aimed to investigate the basal rate and bolus doses in children and adolescents at the start of insulin pump therapy and after 1 year of use.

PATIENTS AND METHODS

Case records from 29 children and adolescents were examined. All pumps were started with rapid-acting insulin (Humalog). Patients were aged 13.1 ± 3.9 years, with a diabetes duration of 5.4 ± 4.1 years at pump start. Sixteen pumps were started for high hemoglobin A1c (HbA1c; >8.8%, 73 mmol/mol) and 13 for other reasons.

RESULTS

Basal rates declined in both groups by 20% at 3 days after pump start. The bolus doses were reduced by 25-30% when the indication was high HbA1c and by 15% in the others. After 1 year, there was a significant difference in the basal rate between age groups. The 3-9-year-old age group had higher basal rates during the late evening (10:00 PM-12:00 AM), while the 15-21-year-old age group had higher basal rates in the early morning (3:00 AM-7:00 AM).

CONCLUSIONS

Insulin doses are reduced considerably when starting with a pump in pediatric practice. Younger children needed higher basal rates late in the evening (reversed dawn phenomenon), while older teenagers seem to need an increase in the morning, which may correspond to a true dawn phenomenon.

Basal rates and circadian profiles in continuous subcutaneous insulin infusion (CSII) differ for preschool children, prepubertal children, adolescents and young adults

OBJECTIVE

Initiation of continuous subcutaneous insulin therapy (CSII) requires an appropriate basal rate profile. Different approaches exist; however, there is a lack of evidence-based recommendations, especially in young children.

STUDY DESIGN

In this large multicenter survey, 5941 CSII patients from the German/Austrian prospective documentation system (DPV) were analyzed. Patients were divided into four age groups: <6 yr (n = 837), 6 to <12 yr (n = 1739), 12 to <18 yr (n = 2985) and 18 to <25 yr (n = 380). Basal insulin requirement and diurnal distribution were evaluated based on the most recent documentation for each patient.

RESULTS

Basal insulin requirement differed significantly between the four age groups (<6: 0.25 ± 0.12; 6 to <12: 0.33 ± 0.12; 12 to <18: 0.43 ± 0.15; 18 to <25: 0.35 ± 0.13 U/kg; p < 0.001). Circadian insulin profiles were markedly different between the younger and older age groups. In addition to age, longer diabetes duration, female gender, higher HbA1c and lower body mass index standard deviation score (BMI-SDS) were related to higher basal insulin requirement per kilogram of body weight.

CONCLUSIONS

Age of the patient is the primary factor that influences both total daily requirement and circadian distribution of basal insulin in CSII. Experience from a large database may therefore facilitate the initiation of pump therapy in pediatric patients.

Insulin delivery by injection in children and adolescents with diabetes

Type 1 diabetes is treated with insulin, which has traditionally been delivered by vial and syringe. However, for many patients, dosing inaccuracy, pain, anxiety, inconvenience, and social acceptability present barriers to this method of administration (1-5). This has contributed to the increased popularity of alternative insulin delivery systems, including pen delivery devices (4, 6). Evidence suggests that discreet devices, such as insulin pens, facilitate adherence to intensive insulin therapy regimens, help improve lifestyle flexibility, and reduce injection pain compared with the conventional syringe-based regimens, as shown in studies in adults and adolescents (7). In addition, compared with the vial and syringe method of insulin administration, pens may provide more accurate dosing - which is particularly important in children - thereby improving short-term blood glucose control and potentially improving long-term outcomes (5, 8). Children, in particular, may benefit from insulin pens that are simple to use as adherence issues may be more evident in this patient group (9). Pens for insulin delivery in children with type 1 diabetes have been used for a long time in Europe, and have recently gained in popularity in many other places around the world (4, 10). Furthermore, the conventional vial and syringe method of insulin delivery is beginning to be considered as obsolete (11). Moreover, there is a continued drive to improve insulin pen technology, to refine and enhance the functionality and usability of these pens. However, despite recent advances in pen design and function, the selection of pens available especially for children is limited.

Treatment of type 1 diabetes in children and adolescents using modern insulin pumps

In the last decades, we are experiencing an increasing use of insulin pumps for the treatment of type 1 diabetes in children and adolescents. The most frequent reasons for switching from insulin injection schemes to pump therapy are frequent and/or severe hypoglycaemia, dawn phenomenon, poor glycaemic control, wish for more flexibility in daily life, and needle phobia. In toddlers and preschoolers, pumps are frequently introduced from the onset of type 1 diabetes. Pumps offer the possibility of adjusting basal insulin rates individually on an age-depended manner as well as of optimizing meal-related insulin requirements according to the meal composition by using three different kinds of boluses. Structured and intensive education of patients and their families on basics and specific requirements of insulin pump therapy is essential in order to get them familiar with the devices and their features. There is increasing evidence both from multicentre cross-sectional studies as well as from meta-analyses of randomized clinical trials in paediatric populations showing that patients with pump therapy can achieve a more favourable metabolic control accompanied with less hypoglycaemic events than those with multiple daily injections.

Insulin dose adjustment when changing from multiple daily injections to continuous subcutaneous insulin infusion in the pediatric age group

The aim of this study is to determine the proper initial dose adjustment when switching from multiple daily injections to continuous subcutaneous insulin infusion for type-1 diabetic pediatric patients. Our hypothesis is that the insulin adjustment varies depending on the pubertal status and the previous long-acting insulin used. Charts of 60 patients were reviewed. Data regarding insulin dose, type of insulin administrated, HbA1c, BMI, severe hypoglycemia and DKA events were collected during the previous year and after 6 weeks of pump therapy. In the prepubertal patients the reduction was 19% (26% if the previous insulin used was detemir). Pubertal patients experienced a decrease of 26%, and the detemir group 33%. The ratio long acting-basal/short acting-bolus insulin changed from 1.26 ± 0.84 to 0.93 ± 0.46 (P < 0.05). The total daily insulin dose needs to be decreased. Basal insulin constitutes 40-45% in prepubertal and 45-50% in pubertal patients. The reduction is different depending on the previous long-acting insulin used; being greater if the insulin is detemir.

Novopen Echo® for the delivery of insulin: a comparison of usability, functionality and preference among pediatric subjects, their parents, and health care professionals

BACKGROUND

Despite advances in insulin pen design and functionality, the selection of pens available for children with diabetes is limited. This study assessed the usability, functionality and attitudes towards NovoPen Echo®, a new durable insulin pen designed for pediatric patients that combines a simple memory function with half-increment dosing, versus NovoPen® Junior and HumaPen® Luxura™ HD in pediatric subjects, their parents, and health care professionals (HCPs).

METHODS

Pens were evaluated in random order during 1:1 interviews in the three target groups (pediatric subjects, parents, and HCPs) in Germany, France, and Canada. Study participants were asked to prepare each pen, perform injections into foam cushions, and provide feedback via a standardized questionnaire.

RESULTS

In total, 205 participants were included in the study. On a scale of 1-6 (1=most favorable; 6=least favorable regarding overall appearance, shape, colors, thickness and length), NovoPen Echo received the most favorable rating for design and overall appearance (mean±standard deviation=1.71±0.79) compared with NovoPen Junior (2.02±0.93) and HumaPen Luxura HD (2.36±1.01). Furthermore, 89% of pediatric subjects and 94% of parents rated the memory function of NovoPen Echo as very easy/easy to use. When asked to rate the pens overall, 80% of participants preferred NovoPen Echo to the other pens (p<0.0001).

CONCLUSIONS

The results demonstrate a high overall level of satisfaction with NovoPen Echo among pediatric subjects, parents, and HCPs. The novel design aspects of NovoPen Echo, namely the simple memory function, half-increment units and, ease of use and design, may contribute towards promoting treatment adherence, which is essential in the pediatric setting.

Factors affecting improved glycaemic control in youth using insulin pumps

AIMS

The purpose of this study was to evaluate factors associated with insulin pump therapy resulting in lower HbA(1c) levels in young people with Type 1 diabetes mellitus.

METHODS

Insulin pumps were downloaded from 150 youth (81 male), ages 5-20 years. Consecutive insulin pump downloads, 3 months apart, were available for 85 (43 male) of the 150 youth and changes in pump use were correlated with changes (≥0.5%, ≥ 6 mmol/mol) in HbA(1c) levels.

RESULTS

  Using cross-sectional data, lower HbA(1c) values correlated with use of more frequent daily insulin boluses (r=-0.46, P<0.0001) and more frequent blood glucose checks/day (r=-0.35, P<0.0001). Young people with HbA(1c) levels <7.5% (58 mmol/mol) vs. values of 7.5-9.0% (58-75 mmol/mol) or ≥ 9.0% (75 mmol/mol) tested blood glucose more frequently/day (P<0.0001), bolused more frequently/day (P<0.0001), reported more grams of carbohydrates eaten/day (P<0.05) and had a higher per cent bolus insulin/day (P<0.05) compared with the ≥9.0% of youth. Using longitudinal data, 48 of 85 patients had a change in HbA(1c) level of ≥0.5% (6 mmol/mol) between downloads (24 improved). Increased bolus insulin (OR=1.15, P=0.03) and time of temporary basal rate use (OR=1.017, P=0.01) predicted ≥0.5% (6 mmol/mol) decrease in HbA(1c) in logistic regression.

CONCLUSIONS

This study emphasizes the importance of blood glucose testing, of bolus insulin administration and of an increase in the time of temporary basal rate use in relation to improving glycaemic control.

Update on mathematical modeling research to support the development of automated insulin delivery systems

One year after its initial meeting, the Glycemia Modeling Working Group reconvened during the 2009 Diabetes Technology Meeting in San Francisco, CA. The discussion, involving 39 scientists, again focused on the need for individual investigators to have access to the clinical data required to develop and refine models of glucose metabolism, the need to understand the differences among the distinct models and control algorithms, and the significance of day-to-day subject variability. The key conclusion was that model-based comparisons of different control algorithms, or the models themselves, are limited by the inability to access individual model-patient parameters. It was widely agreed that these parameters, as opposed to the average parameters that are typically reported, are necessary to perform such comparisons. However, the prevailing view was that, if investigators were to make the parameters available, it would limit their ability (and that of their institution) to benefit from the invested work in developing their models. A general agreement was reached regarding the importance of each model having an insulin pharmacokinetic/pharmacodynamic profile that is not different from profiles reported in the literature (88% of the respondents agreed that the model should have similar curves or be analyzed separately) and the importance of capturing intraday variance in insulin sensitivity (91% of the respondents indicated that this could result in changes in fasting glucose of >or=15%, with 52% of the respondents believing that the variability could effect changes of >or=30%). Seventy-six percent of the participants indicated that high-fat meals were thought to effect changes in other model parameters in addition to gastric emptying. There was also widespread consensus as to how a closed-loop controller should respond to day-to-day changes in model parameters (with 76% of the participants indicating that fasting glucose should be within 15% of target, with 30% of the participants believing that it should be at target). The group was evenly divided as to whether the glucose sensor per se continues to be the major obstacle in achieving closed-loop control. Finally, virtually all participants agreed that a future two-day workshop should be organized to compare, contrast, and understand the differences among the different models and control algorithms.

Changes in basal insulin infusion rates with subcutaneous insulin infusion: time until a change in metabolic effect is induced in patients with type 1 diabetes

OBJECTIVE Evaluation of the time required until a change in the basal insulin infusion rate with an insulin pump induces subsequent changes in the metabolic effect. RESEARCH DESIGN AND METHODS In this euglycemic glucose clamp study, 10 male subjects with type 1 diabetes received three different subcutaneous insulin infusion rates (0.5, 1.0, and 2.0 units/h; for 4 h each) of insulin lispro (IL) with insulin pumps. RESULTS An increase in insulinemia occurred within 15-30 min after changing the infusion rate. While the serum IL levels reached a steady state at the end of the infusion period, the glucose infusion rates did not always reach steady-state levels with the higher infusion rates. However, an increase in the glucose consumption occurred within 30-60 min after switching the infusion rate. CONCLUSIONS Several hours are required until a new steady state in the metabolic effect is achieved after a significant change in basal insulin infusion.

Insulin pump therapy: guidelines for successful outcomes

PURPOSE

Current forms of insulin delivery used in the treatment of diabetes mellitus (diabetes) include syringes, pens, and insulin pumps. Technical advantages of insulin pump therapy, or continuous subcutaneous insulin delivery (CSII), include precise and flexible insulin dosing. In the context of intensive diabetes management, insulin pumps can facilitate improved long-term glycemic control and reduce the risk for diabetes complications, with improved lifestyle flexibility for patients and their families. Comprehensive patient education, carbohydrate counting, and frequent self-monitoring of blood glucose or continuous glucose monitoring are necessary components of successful insulin pump therapy. Technological advances have increased the appeal of pump therapy to patients and clinicians. Physically, current insulin pumps are discreet, ergonomic, and water resistant. Meanwhile, software improvements have yielded smart pumps with features that support pump users in their daily diabetes management. Robust data analysis software packages allow patients and clinicians unprecedented insight into the quality of diabetes control. Furthermore, widespread insurance reimbursement for CSII has expanded access to therapy.

CONCLUSIONS

As the number of pump users and potential users expands, diabetes educators face new challenges and opportunities to improve patients' lives with diabetes. This activity describes the rationale for insulin pump therapy, its potential advantages and disadvantages, and strategies regarding patient selection and education.

Insulin requirement in preschoolers treated with insulin pumps at the onset of type 1 diabetes mellitus

THE AIM

The aim of this study is to analyze changes in the basal insulin requirement in preschoolers treated with insulin pump at the onset of T1DM, using system to calculate meal time insulin.

METHODS

58 children (31 girls) under 6 years (mean age 3.3 +/- 1.5 years) initiated on insulin pump therapy within 2 months after recognition of T1DM and treated at least for 1 year were analyzed during a follow-up period of 165 patient-years. Data was collected every 6 months: HbA1c, BMI SDS, diabetic ketoacidosis, severe hypoglycaemia, total daily insulin dose (TDD) and basal insulin.

RESULTS

Basal insulin rose from 10% in the third month and did not exceed 30% of TDD after 12 months (p<0.0001). In the third month, 46% of children were without basal insulin; this group included significantly older children (3.7 +/- 1.4 vs. 2.8 +/- 1.4 years; p = 0.01), which had lower TDD (0.33 +/- 0.18 vs. 0.54 +/- 0.23 u/kg/d; p = 0.0007) than children with basal insulin. HbA1c persisted < or =7.3%.

CONCLUSION

In preschool children initiated on CSII therapy at the time of T1DM diagnosis the first year of treatment is critical for altering the basal insulin dose. Preschoolers with TDD lower than 0.5 U/kg/d may not require basal insulin. Moreover, basal insulin did not exceed 30% of TDD in the first years after T1DM onset.

Mathematical modeling research to support the development of automated insulin-delivery systems

The world leaders in glycemia modeling convened during the Eighth Annual Diabetes Technology Meeting in Bethesda, Maryland, on 14 November 2008, to discuss the current practices in mathematical modeling and make recommendations for its use in developing automated insulin-delivery systems. This report summarizes the collective views of the 25 participating experts in addressing the following four topics: current practices in modeling efforts for closed-loop control; framework for exchange of information and collaboration among research centers; major barriers for the development of accurate models; and key tasks for developing algorithms to build closed-loop control systems. Among the participants, the following main conclusions and recommendations were widely supported: 1. Physiologic variance represents the single largest technical challenge to creating accurate simulation models. 2. A Web site describing different models and the data supporting them should be made publically available, with funding agencies and journals requiring investigators to provide open access to both models and data. 3. Existing simulation models should be compared and contrasted, using the same evaluation and validation criteria, to better assess the state of the art, understand any inherent limitations in the models, and identify gaps in data and/or model capability.

Age-dependent basal insulin patterns in children with type 1 diabetes treated with continuous subcutaneous insulin infusion

AIMS

Identifying age-dependent basal rates in type 1 diabetic children treated with continuous subcutaneous insulin infusion (CSII).

METHODS

CSII-treated children with type 1 diabetes exhibiting insulin requirement > 0.5 U/kg and glycated haemoglobin (HbA1c) < 8%. The study population was composed of 198 Caucasian children (111 girls) with mean age of 9.8 +/- 3.8 years, mean duration of diabetes of 4.3 +/- 3.1 years and mean HbA1c value of 6.7 +/- 0.7%. Data were evaluated for four age groups (0-6; 6-9; 9-12, 12-18 years). Basal rates records were downloaded from pump memory. HbA1c, weight, height were measured at scheduled visits.

RESULTS

Significant differences in the average hourly basal rate between groups were observed: I gr. 0.14 versus II gr. 0.24 versus III gr. 0.39 versus IV gr. 0.72 units/h; p < 0.0001. The average hourly basal rate correlated with age, body weight, BMI, diabetes duration and total insulin daily dose. Insulin peaks were observed for: I gr. - before midnight, II gr. - before midnight and in the early morning, gr. III and IV - in the early morning.

CONCLUSION

Basal insulin infusion rate profiles in well-controlled paediatric patients on CSII reflect the age-dependent amount of basal insulin (20-40%) and affect circadian distribution of insulin needs.