Sensor-augmented pump therapy from the diagnosis of childhood type 1 diabetes: results of the Paediatric Onset Study (ONSET) after 12 months of treatment

Current concepts in blood glucose monitoring

Blood glucose monitoring has evolved over the last century. The concept of adequate glycemic control and minimum glycemic variability requires an ideal, accurate and reliable glucose monitoring system. The search for an ideal blood glucose monitoring system still continues. This review explains the various blood glucose monitoring systems with special focus on the monitoring systems like self- monitored blood glucose (SMBG) and continuous glucose monitoring system (CGMS). It also focuses on the newer concepts of blood glucose monitoring and their incorporation in routine clinical management of diabetes mellitus.

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

OBJECTIVE

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

RESEARCH DESIGN AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Technology to optimize pediatric diabetes management and outcomes

Technology for diabetes management is rapidly developing and changing. With each new development, there are numerous factors to consider, including medical benefits, impact on quality of life, ease of use, and barriers to use. It is also important to consider the interaction between developmental stage and technology. This review considers a number of newer diabetes-related technologies and explores issues related to their use in the pediatric diabetes population (including young adults), with a focus on psychosocial factors. Areas include trend technology in blood glucose monitoring, continuous glucose monitoring, sensor-augmented insulin pumps and low glucose suspend functions, internet applications including videoconferencing, mobile applications (apps), text messaging, and online gaming.

Continuous glucose monitoring: current use and future directions

Continuous glucose monitoring (CGM) is an emerging technology that provides a continuous measure of interstitial glucose levels. In addition to providing a more complete pattern of glucose excursions, CGMs utilize real-time alarms for thresholds and predictions of hypo- and hyperglycemia, as well as rate of change alarms for rapid glycemic excursions. CGM users have been able to improve glycemic control without increasing their risk of hypoglycemia. Sensor accuracy, reliability, and wearability are important challenges to CGM success and are critical to the development of an artificial pancreas (or closed-loop system).

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

BACKGROUND

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

SUBJECTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Hyperglycaemia and β-cell antibodies: is it always pre-type 1 diabetes?

We describe 10-year-old girl with mild incidental hyperglycaemia, impaired glucose tolerance and GADA positivity. Family history for mild hyperglycaemia and GADA fluctuation alerted us to a possible MODY diagnosis which was confirmed by detection of GCK mutation c.626C>T; p.T209M. Weak or transient β-cell autoimmunity should not preclude genetic testing for MODY when the clinical features are suggestive.

The role of continuous glucose monitoring in the care of children with type 1 diabetes

Continuous glucose monitoring (CGM), while a relatively new technology, has the potential to transform care for children with type 1 diabetes. Some, but not all studies, have shown that CGM can significantly improve hemoglobin A1c levels and reduce time spent in the hypoglycemic range in children, particularly when used as part of sensor-augmented pump (SAP) therapy. Despite the publication of recent clinical practice guidelines suggesting CGM be offered to all children 8 years of age or older who are likely to benefit, and studies showing that younger children can also benefit, this technology is not yet commonly used by children with type 1 diabetes. Effects of CGM are enhanced when used on a near-daily basis (a use-dependent effect) and with insulin pump therapy. Therefore, coordinated strategies are needed to help children and their families initiate and continue to use this resource for diabetes care. This review introduces CGM to pediatric endocrinologists who are not yet familiar with the finer details of this technology, summarizes current data showing the benefits and limitations of CGM use in children, reviews specific case examples demonstrating when CGM can be helpful, and shows the value of both retrospective and real-time CGM. It is hoped that this information leads to discussion of this technology in pediatric endocrinology clinics as an important next step in improving the care of children with type 1 diabetes.

Continuous glucose monitoring: evidence and consensus statement for clinical use

Continuous glucose monitoring (CGM) is an essential tool for modern diabetes therapy. Randomized controlled studies have provided evidence that hemoglobin A1c (HbA1c) results can be improved in patients with type 1 diabetes with elevated baseline HbA1c when using CGM frequently enough and that the frequency and duration of hypoglycemic events can be reduced in patients with satisfactory baseline HbA1c. The CGM group within the Working Group Diabetes Technology (AGDT) of the German Diabetes Association (DDG) has defined evidence-based indications for the practical use of CGM in this consensus statement related to hypoglycemia (frequent, severe, or nocturnal) or hypoglycemia unawareness, insufficient metabolic control despite use of all possible therapeutic options and patient compliance, pregnancy associated with inadequate blood glucose results, and the need for more than 10 blood glucose measurements per day. Contraindications and defined preconditions for the successful use of CGM should be considered.

Continuous glucose monitoring in type 1 diabetes

Continuous glucose monitors (CGM), devices that can measure interstitial glucose in "real time," have become widely available particularly for use in patients with diabetes, and their accuracy and ease of use have greatly improved over the last decade. A number of large and well-controlled clinical trials have firmly established their usefulness in improving metabolic control (as measured by HbA1C) and decreasing time spent in hypoglycemia in adults; however, data have been less robust proving benefit in children and adolescents. Benefits are clearly linked to near-continuous wear. Insulin dosing algorithms based on CGM glucose trends have proven useful in dissecting the large volume of data generated daily by these devices, although these are imperfect tools, particularly in children. The technology is likely to be most useful when integrated with insulin pump delivery systems (sensor augmented). In this review, we concentrate on the analysis of published results of the largest trials in adults and children, including the very young, with diabetes.

Systematic review and meta-analysis of the effectiveness of continuous glucose monitoring (CGM) on glucose control in diabetes

Diabetes mellitus is a chronic disease that necessitates continuing treatment and patient self-care education. Monitoring of blood glucose to near normal level without hypoglycemia becomes a challenge in the management of diabetes. Although self monitoring of blood glucose (SMBG) can provide daily monitoring of blood glucose level and help to adjust therapy, it cannot detect hypoglycemic unawareness and nocturnal hypoglycemia which occurred mostly in T1DM pediatrics. Continuous glucose monitoring (CGM) offers continuous glucose data every 5 minutes to adjust insulin therapy especially for T1DM patients and to monitor lifestyle intervention especially for T2DM patients by care providers or even patients themselves. The main objective of this study was to assess the effects of continuous glucose monitoring (CGM) on glycemic control in Type 1 diabetic pediatrics and Type 2 diabetic adults by collecting randomized controlled trials from MEDLINE (pubmed), SCOPUS, CINAHL, Web of Science and The Cochrane Library up to May 2013 and historical search through the reference lists of relevant articles. There are two types of CGM device: real-time CGM and retrospective CGM and both types of the device were included in the analysis. In T1DM pediatrics, CGM use was no more effective than SMBG in reducing HbA1c [mean difference - 0.13% (95% CI -0.38% to 0.11%,]. This effect was independent of HbA1c level at baseline. Subgroup analysis indicated that retrospective CGM was not superior to SMBG [mean difference -0.05% (95% CI -0.46% to 0.35%)]. In contrast, real-time CGM revealed better effect in lowering HbA1c level compared with SMBG [mean difference -0.18% (95% CI -0.35% to -0.02%, p = 0.02)]. In T2DM adults, significant reduction in HbA1c level was detected with CGM compared with SMBG [mean difference - 0.31% (95% CI -0.6% to -0.02%, p = 0.04)]. This systematic review and meta-analysis suggested that real-time CGM can be more effective than SMBG in T1DM pediatrics, though retrospective CGM was not. CGM provided better glycemic control in T2DM adults compared with SMBG.

[CGM-continuous glucose monitoring - statement of the Austrian Diabetes Association]

This position statement represents the recommendations of the Austrian Diabetes Association regarding the clinical diagnostic and therapeutic application, safety and benefits of continuous subcutaneous glucose monitoring systems in patients with diabetes mellitus, based on current evidence.

Sensor augmented pump therapy from onset of type 1 diabetes: late follow-up results of the Pediatric Onset Study

AIM

To evaluate the metabolic control and β-cell function 1 yr after the end of the European multicentre randomized Pediatric Onset Study.

METHODS

Of 154 study patients, 131 were re-examined 24 months after type 1 diabetes onset (49.6% boys, age at onset 8.9 ± 4.3 yrs). Of which, 62 patients belonged to the primary group of the main study applying a sensor-augmented pump system during the first yr and 69 patients to the control group performing conventional insulin pump therapy with self-monitoring blood glucose. HbA1c, fasting blood glucose, and C-peptide were centrally measured (Clinical Trail Registration Number: ISRCTN05450731).

RESULTS

At 24 months, i.e., 1 yr after the end of the interventional study, 52.4% of the patients used the sensor-augmented pump system, 46.0% conventional pump, and 1.6% multiple daily injections. HbA1c was 7.6 ± 1.3% in the primary and 7.7 ± 1.2% in the control group (p = 0.493). Frequent sensor use during the first yr was associated with statistically insignificant lowering of the HbA1c at 24 months (p = 0.236) as compared with irregular or no sensor use (7.4 ± 1.0% vs. 7.7 ± 1.3%). Although fasting C-peptide was not clearly different between the primary and control group (0.13 ± 0.17 vs. 0.09 ± 0.10 nmol/L, p = 0.121), patients with frequent sensor use had significantly less C-peptide loss within 24 months (C-peptide reduction 0.02 ± 0.18 vs. 0.07 ± 0.11 nmol/L, p = 0.046). There was no difference between the groups regarding daily insulin requirements.

CONCLUSION

Sensor-augmented pump therapy from onset of diabetes may lead to better long-term glycemic control and help to preserve endogenous β-cell function, if patients comply with frequent use of continuous glucose monitoring.

Continuous glucose monitoring in children and adolescents

Continuing glucose monitoring (CGM) is a relatively new and rapidly developing technology that shows promise for the future management of type 1 diabetes. When used with near-daily frequency, it has a significant effect on improvement of glucose metabolism as measured by HbA1C and reduction of hypoglycemia. It appears to be safe and actually reduces both DKA and severe hypoglycemia. Early studies indicate that it should be cost effective.

Is continuous glucose monitoring (CGM) for everyone? To whom should CGM be prescribed and how?

Are all type 1 diabetes (T1DM) patients potential candidates for continuous glucose monitoring (CGM)? Clearly, some patients improve their metabolic control with this tool, such as adults with poor metabolic control, especially those treated with continuous subcutaneous insulin infusion (CSII), and compliant patients with HbA(1c) levels <7%. There are also less good candidates for CGM, such as patients aged 8-18 years because they are reluctant to wear the sensors or those with new-onset T1DM. Other patient groups have not yet been evaluated, such as patients aged <8 years, women during pregnancy, and those with HbA(1c) >10% and/or severe hypoglycaemia. Beyond the indications, the mode of use of CGM is crucial. An appropriate patient selection, in order to choose those able to run the tool and motivated to use it, is necessary. How to prescribe the sensors is also an important question. Two approaches have been compared: patient-led and physician-driven prescription. Both modes of using CGM provide similar long-term metabolic improvement. However, physician-driven prescription is probably more cost-effective. The last key question is the education of patients by an experienced team. It can help them to translate the large amount of data from the monitor into effective self-management for optimalizing the CGM experience. However, elaboration of a validated algorithm is necessary to take full advantage of this device.

Personal continuous glucose monitoring (CGM) in diabetes management: review of the literature and implementation for practical use

AIM

Despite recent advances in diabetes therapy including the new long- and rapid-insulin analogs, insulin intensification strategies such as basal/bolus or pump therapy and sophisticated methods for insulin titration derived from the principles of functional insulin therapy, many patients fail to reach or maintain target glycosylated hemoglobin (HbA1c) values, putting them at increased risk for vascular complications. Continuous glucose monitoring (CGM) systems represent an important advance in diabetes technology that can facilitate optimal glucose control in type 1 diabetes.

METHOD

This review focuses on the efficacy and safety of CGM systems in diabetes management. The different CGM devices available are also described, as the way to use them and the educational approach to the patient in a step-by-step progression toward optimal glycemic control.

RESULTS

In type 1 diabetes, CGM systems are associated with 0.5-1% reduction in HbA1c without increased risk of hypoglycemia. CGM efficacy correlates with compliance to sensor wear, whatever the patient's age range.

CONCLUSION

Efficacy of CGM systems is now proven but indications, terms of use and educational issues of this new technology still need to be specified.

Beneficial effect of real-time continuous glucose monitoring system on glycemic control in type 1 diabetic patients: systematic review and meta-analysis of randomized trials

OBJECTIVE

Real-time continuous glucose monitoring (RT-CGM) provides detailed information on glucose patterns and trends, thus allowing the patients to manage their diabetes more effectively.

DESIGN

The aim of this study was to explore the potential beneficial effects of the use of RT-CGM on diabetes management compared with self blood glucose measurement (SBGM) in patients with type 1 diabetes mellitus (T1DM), by means of a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

MEDLINE, EMBASE, and the Cochrane Library were searched through by two independent investigators for RCTs concerning the use of RT-CGM in patients with T1DM. Only studies with a similar insulin regimen in the experimental and control groups were included in the analysis.

RESULTS

Seven RCTs (n=948) met the inclusion criteria. Combined data from all studies showed better HbA1c reduction in subjects using RT-CGM compared with those using SBGM (mean difference (MD) -0.25; 95% confidence interval (95% CI): from -0.34 to -0.17; P<0.001). Patients treated with insulin pump and RT-CGM had a lower HbA1c level compared with subjects managed with insulin pump and SBGM (four RCTs, n=497; MD -0.26; 95% CI: from -0.43 to -0.10; P=0.002). The benefits of applying RT-CGM were not associated with an increasing rate of major hypoglycemic episodes. The use of RT-CGM for over 60-70% of time was associated with a significant lowering of HbA1c.

CONCLUSIONS

RT-CGM is more beneficial than SBGM in reducing HbA1c in patients with type 1 diabetes. Further studies are needed to evaluate the efficacy of this system in the pediatric population, especially in very young children.

Accuracy of the Enlite 6-day glucose sensor with guardian and Veo calibration algorithms

OBJECTIVE

This study investigates the accuracy of a newly developed, next-generation subcutaneous glucose sensor, evaluated for 6-day use.

RESEARCH DESIGN AND METHODS

Seventy-nine subjects (53 men, 26 women) with type 1 diabetes and 18 subjects (14 men, four women) with type 2 diabetes completed a three-center, prospective, sensor accuracy study. The mean age for the group was 42.2±15.0 years (mean±SD), ranging from 18 to 71 years, with a mean glycosylated hemoglobin level of 7.6±1.5%, ranging from 5.5% to 14%. Subjects wore Enlite™ sensors (Medtronic Diabetes, Northridge, CA) in the abdominal and buttocks region for two separate 7-day periods and calibrated with a home-use blood glucose meter. Subjects participated in an in-clinic testing day where frequent sampled plasma glucose samples were acquired every 15 min for 10 h. Sensor data was retrospectively processed with Guardian(®) REAL-Time (Medtronic) and Paradigm(®) Veo™ (Medtronic) calibration routines, and accuracy metrics were calculated for each algorithm and sensor location. Physiological time lag for each measurement site was calculated.

RESULTS

Based on 6,404 plasma-sensor glucose paired points, the Enlite sensor with Veo calibration algorithm produced a mean absolute relative difference of 13.86% with 97.3% of points within the A+B zones of the Clarke error grid. Threshold-only alarms detected 90.1% of hypoglycemia and 90% of hyperglycemia. Mean time lag measured at the abdominal region was 7.94±6.48 min compared with 11.70±6.71 min (P<0.0001) at the buttocks area.

CONCLUSIONS

The Enlite sensor accurately measures glucose when compared with gold standard laboratory measurements over its 6-day use. Sensors placed in the buttocks region exhibited greater time lags than sensors placed in the abdomen.

Management of diabetes mellitus: is the pump mightier than the pen?

Continuous subcutaneous insulin infusion (CSII, or insulin pump therapy) reduces HbA1c levels and hypoglycaemia in patients with type 1 diabetes mellitus (T1DM) compared with multiple daily insulin injections (MDI). The greatest reduction in HbA(1c) levels with CSII occurs in patients with the worst glycaemic control; therefore, the most appropriate and cost-effective use of CSII in adults with T1DM is in those who have continued, elevated HbA(1c) levels or disabling hypoglycaemic episodes with MDI (including the use of long-acting insulin analogues and structured patient education). The disadvantages of CSII include higher costs than MDI and the risk of ketosis in the event of pump failure. In children with T1DM, CSII may be used when MDI is considered impractical or inappropriate. Pumps are not generally recommended for patients with type 2 diabetes mellitus but may improve control in some subgroups. A new generation of smaller insulin infusion pumps with an integrated cannula, called patch pumps, could improve uptake of CSII in general. The important clinical question is not whether CSII is more efficacious than MDI in general adult T1DM, but whether CSII further improves glycaemic control when this control continues to be poor with MDI, and evidence exists that in most cases it does.

Continuous glucose monitoring in children, adolescents, and adults with type 1 diabetes mellitus: analysis from the prospective DPV diabetes documentation and quality management system from Germany and Austria

OBJECTIVE

To determine frequency, duration, and relationship of continuous glucose monitoring (CGM) to glycemic control and rate of hypoglycemia in children and adults in Germany and Austria.

RESEARCH DESIGN AND METHODS

From 59,920 patients documented in the DPV (Diabetessoftware zur prospektiven Verlaufsdokumentation) database, 144,385 sensor days of 2874 patients using CGM between January 2008 and September 2010 were analyzed.

RESULTS

Overall, 4.8% of patients used CGM. In pediatric patients, study period (p = 0.0309), age (p = 0.0140), insulin dose (p < 0.0001), and use of insulin analogs (p < 0.0001) significantly influenced hemoglobin A1c (HbA1c), but duration of diabetes, sex, and CGM use did not. In contrast, adults with longer CGM use (>30 d) had significantly lower HbA1c (p < 0.0016). Severe hypoglycemia was not reduced in patients using CGM for <30 d.

CONCLUSIONS

CGM is still rarely used in Germany and Austria. CGM use is associated with a significant reduction of HbA1c in adults but not in children. Hypoglycemic events were not reduced, irrespective of age.

Continuous glucose monitoring systems for type 1 diabetes mellitus

BACKGROUND

Self-monitoring of blood glucose is essential to optimise glycaemic control in type 1 diabetes mellitus. Continuous glucose monitoring (CGM) systems measure interstitial fluid glucose levels to provide semi-continuous information about glucose levels, which identifies fluctuations that would not have been identified with conventional self-monitoring. Two types of CGM systems can be defined: retrospective systems and real-time systems. Real-time systems continuously provide the actual glucose concentration on a display. Currently, the use of CGM is not common practice and its reimbursement status is a point of debate in many countries.

OBJECTIVES

To assess the effects of CGM systems compared to conventional self-monitoring of blood glucose (SMBG) in patients with diabetes mellitus type 1.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE and CINAHL for the identification of studies. Last search date was June 8, 2011.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing retrospective or real-time CGM with conventional self-monitoring of blood glucose levels or with another type of CGM system in patients with type 1 diabetes mellitus. Primary outcomes were glycaemic control, e.g. level of glycosylated haemoglobin A1c (HbA1c) and health-related quality of life. Secondary outcomes were adverse events and complications, CGM derived glycaemic control, death and costs.

DATA COLLECTION AND ANALYSIS

Two authors independently selected the studies, assessed the risk of bias and performed data-extraction. Although there was clinical and methodological heterogeneity between studies an exploratory meta-analysis was performed on those outcomes the authors felt could be pooled without losing clinical merit.

MAIN RESULTS

The search identified 1366 references. Twenty-two RCTs meeting the inclusion criteria of this review were identified. The results of the meta-analyses (across all age groups) indicate benefit of CGM for patients starting on CGM sensor augmented insulin pump therapy compared to patients using multiple daily injections of insulin (MDI) and standard monitoring blood glucose (SMBG). After six months there was a significant larger decline in HbA1c level for real-time CGM users starting insulin pump therapy compared to patients using MDI and SMBG (mean difference (MD) in change in HbA1c level -0.7%, 95% confidence interval (CI) -0.8% to -0.5%, 2 RCTs, 562 patients, I(2)=84%). The risk of hypoglycaemia was increased for CGM users, but CIs were wide and included unity (4/43 versus 1/35; RR 3.26, 95% CI 0.38 to 27.82 and 21/247 versus 17/248; RR 1.24, 95% CI 0.67 to 2.29). One study reported the occurrence of ketoacidosis from baseline to six months; there was however only one event. Both RCTs were in patients with poorly controlled diabetes.For patients starting with CGM only, the average decline in HbA1c level six months after baseline was also statistically significantly larger for CGM users compared to SMBG users, but much smaller than for patients starting using an insulin pump and CGM at the same time (MD change in HbA1c level -0.2%, 95% CI -0.4% to -0.1%, 6 RCTs, 963 patients, I(2)=55%). On average, there was no significant difference in risk of severe hypoglycaemia or ketoacidosis between CGM and SMBG users. The confidence interval however, was wide and included a decreased as well as an increased risk for CGM users compared to the control group (severe hypoglycaemia: 36/411 versus 33/407; RR 1.02, 95% CI 0.65 to 1.62, 4 RCTs, I(2)=0% and ketoacidosis: 8/411 versus 8/407; RR 0.94, 95% CI 0.36 to 2.40, 4 RCTs, I(2)=0%).Health-related quality of life was reported in five of the 22 studies. In none of these studies a significant difference between CGM and SMBG was found. Diabetes complications, death and costs were not measured.There were no studies in pregnant women with diabetes type 1 and in patients with hypoglycaemia unawareness.

AUTHORS' CONCLUSIONS

There is limited evidence for the effectiveness of real-time continuous glucose monitoring (CGM) use in children, adults and patients with poorly controlled diabetes. The largest improvements in glycaemic control were seen for sensor-augmented insulin pump therapy in patients with poorly controlled diabetes who had not used an insulin pump before. The risk of severe hypoglycaemia or ketoacidosis was not significantly increased for CGM users, but as these events occurred infrequent these results have to be interpreted cautiously.There are indications that higher compliance of wearing the CGM device improves glycosylated haemoglobin A1c level (HbA1c) to a larger extent. 

Recent advances in the prevention of hypoglycemia in type 1 diabetes

Iatrogenic hypoglycemia is one of the chief barriers to optimal glycemic control in people with type 1 diabetes (T1D). As a common contributor to morbidity and mortality in T1D, severe hypoglycemia (SH) is also a major fear for people with T1D and their families. Consequently, fear of hypoglycemia and hypoglycemia-avoidant behaviors are predominant limiting factors in achieving euglycemia in people with T1D. Nocturnal SH and hypoglycemia unawareness are prevalent obstacles in the detection of hypoglycemia which further impair the prevention and treatment of SH. Various strategies and technologies have already been developed to help detect and prevent hypoglycemia, including improved patient education, frequent self-monitoring of blood glucose levels, the use of rapid-acting and basal insulin analogs, continuous subcutaneous insulin infusion therapy, exercise-related insulin modifications, and continuous glucose monitors. The efficacy of these methods is well established, but further advances are still needed. The purpose of this review is to describe these currently available methods and to emphasize recent progress related to the prevention of hypoglycemia in T1D.

Comparison between sensor-augmented insulin therapy with continuous subcutaneous insulin infusion or multiple daily injections in everyday life: 3-day analysis of glucose patterns and sensor accuracy in children

BACKGROUND

Sensor-augmented continuous subcutaneous insulin infusion (CSII) therapy is superior to CSII therapy alone, but little is known on the effectiveness of sensor-augmented multiple daily injections (MDI) therapy.

METHODS

We compared during everyday life mean glucose control and several variability indexes recorded for 3 days by a real-time glucose sensor (Medtronic, Northridge, CA) in two groups of children treated with either CSII or MDI. Fifty-five consecutive subjects were examined: 17 receiving CSII and 38 receiving MDI basal-bolus therapy (age range, 7-22 years). All subjects wore the sensor for 4 days, and 3 days were used for statistical analysis. Mean glucose and SD, coefficient of variation (CV), mean amplitude of glucose excursion (MAGE), mean of daily differences (MODD), continuous overall net glycemic action (CONGA) at 2 and 4 h, blood glucose (BG) rate, area under the curve (AUC) above 180 mg/dL and below 70 mg/dL, Low BG Index (LBGI), and High BG Index (HBGI) were calculated.

RESULTS

Patients receiving CSII administered more daily boluses than patients receiving MDI (5.2±1.5 vs. 3.2±0.3, respectively; P=0.001). Mean glucose was lower in the CSII group. AUC above 180 mg/dL and HBGI were higher in the MDI group. CV, CONGA at 2 h, CONGA at 2 h during the day, and HBGI were worse in the MDI group, whereas MODD, LBGI, BG rate, and MAGE were similar. A positive correlation (r=0.95; P<0.05) was found between the paired sensor-meter values. For the glucose values <70 mg/dL, sensitivity was 40%, and specificity was 99%.

CONCLUSIONS

In our pediatric patients during everyday life sensor-augmented CSII therapy seemed more effective than sensor-augmented MDI therapy, in terms both of glucose mean values and of intraday variability. Mild hypoglycemic episodes and indexes of low BG values were similar in the two groups, although the latter results may be inaccurate because of low sensor sensitivity at low glucose value.

Management of diabetes mellitus in infants

Diabetes mellitus diagnosed during the first 2 years of life differs from the disease in older children regarding its causes, clinical characteristics, treatment options and needs in terms of education and psychosocial support. Over the past decade, new genetic causes of neonatal diabetes mellitus have been elucidated, including monogenic β-cell defects and chromosome 6q24 abnormalities. In patients with KCNJ11 or ABCC8 mutations and diabetes mellitus, oral sulfonylurea offers an easy and effective treatment option. Type 1 diabetes mellitus in infants is characterized by a more rapid disease onset, poorer residual β-cell function and lower rate of partial remission than in older children. Insulin therapy in infants with type 1 diabetes mellitus or other monogenic causes of diabetes mellitus is a challenge, and novel data highlight the value of continuous subcutaneous insulin infusion in this very young patient population. Infants are entirely dependent on caregivers for insulin therapy, nutrition and glucose monitoring, which emphasizes the need for appropriate education and psychosocial support of parents. To achieve optimal long-term metabolic control with low rates of acute and chronic complications, continuous and structured diabetes care should be provided by a multidisciplinary health-care team.

New-generation diabetes management: glucose sensor-augmented insulin pump therapy

Diabetes is one of the most common chronic disorders with an increasing incidence worldwide. Technologic advances in the field of diabetes have provided new tools for clinicians to manage this challenging disease. For example, the development of continuous subcutaneous insulin infusion systems have allowed for refinement in the delivery of insulin, while continuous glucose monitors provide patients and clinicians with a better understanding of the minute to minute glucose variability, leading to the titration of insulin delivery based on this variability when applicable. Merging of these devices has resulted in sensor-augmented insulin pump therapy, which became a major building block upon which the artificial pancreas (closed-loop systems) can be developed. This article summarizes the evolution of sensor-augmented insulin pump therapy until present day and its future applications in new-generation diabetes management.

Closed-loop glucose control: psychological and behavioral considerations

Since 2000, the diabetes community has witnessed tremendous technological advances that have revolutionized diabetes management. Currently, closed-loop glucose control (CLC) systems, which link continuous subcutaneous insulin infusion and continuous glucose monitoring, are the newest, cutting edge technology aimed at reducing glycemic variability and improving daily management of diabetes. Although advances in knowledge and technology in the treatment of diabetes have improved exponentially, adherence to diabetes regimens remains complex and often difficult to predict. Human factors, such as patient perceptions and behavioral self-regulation, are central to adherence to prescribed regimens, as well as to adoption and utilization of diabetes technology, and they will continue to be crucial as diabetes management evolves. Thus, the aims of this article are three-fold: (1) to review psychological and behavioral factors that have influenced adoption and utilization of past technologies, (2) to examine three theoretical frameworks that may help in conceptualizing relevant patient factors in diabetes management, and (3) to propose patient-selection factors that will likely affect future CLC systems.

Prevention of hypoglycemia by using low glucose suspend function in sensor-augmented pump therapy

BACKGROUND

Severe hypoglycemic episodes are a barrier for achieving optimal glycemic control. Sensor-augmented pump (SAP) therapy with insulin in combination with a novel mechanism of automatic insulin shutoff (low glucose suspend [LGS]) can be used to prevent and reduce hypoglycemia. In a prospective study, we investigated the effect of the LGS algorithm on the frequency of hypoglycemia in children and adolescents with type 1 diabetes under real-life conditions.

METHODS

Twenty-one patients with type 1 diabetes (10.8±3.8 years old, duration of diabetes 5.9±3.0 years, pump therapy for 3.7±1.7 years, glycated hemoglobin level 7.8±1.1%) from three pediatric centers used the Paradigm(®) Veo(™) system (Medtronic Minimed, Northridge, CA) during two subseqent time periods: SAP without LGS for 2 weeks and then SAP with LGS enabled for 6 weeks. The primary objective was to assess the frequency of hypoglycemic episodes when using the LGS feature with an insulin delivery shutoff of a maximum of 2 h at a sensor glucose level below 70 mg/dL (3.9 mmol/L).

RESULTS

In total, 1,298 LGS alerts occurred (853 shorter than 5 min). Forty-two percent of LGS activations (>5 min) lasted less than 30 min, whereas 24% had a duration of 2 h. The number of hypoglycemic excursions (average/day) was reduced during SAP+LGS (<70 mg/L, 1.27±0.75 vs. 0.95±0.49, P=0.010; ≤40 mg/dL, 0.28±0.18 vs. 0.13±0.14, P=0.005) as was the time spent in hypoglycemia (average minutes/day, 101±68 vs. 58±33, P=0.002) without significant difference in the mean glucose level (145±23 vs. 148±19 mg/dL). No episodes of severe hyperglycemia or diabetic ketoacidosis were observed following LGS activation.

CONCLUSIONS

The present investigation provides evidence that SAP with LGS reduces the frequency of hypoglycemia without compromising safety.

Insulin pump therapy started at the time of diagnosis: effects on glycemic control and pancreatic β-cell function in type 1 diabetes

BACKGROUND

In the interest of preserving residual insulin secretory capacity present at the time of diagnosis with type 1 diabetes (T1D), we compared the efficacy of starting insulin pump therapy at diagnosis with standard multiple daily insulin injections (MDIs).

METHODS

We conducted a prospective, randomized, pilot trial comparing MDI therapy with continuous subcutaneous insulin therapy (pump therapy) in 24 patients, 8-18 years old, with newly diagnosed T1D. Subjects were evaluated at enrollment and 1, 3, 6, 9, and 12 months after initial diagnosis of T1D. Preservation of insulin secretion, measured by mixed-meal-stimulated C-peptide secretion, was compared after 6 and 12 months of treatment. Between-group differences in glycosylated hemoglobin (HbA1c), continuous glucose sensor data, insulin utilization, anthropometric measures, and patient satisfaction with therapy were also compared at multiple time points.

RESULTS

Initiation of pump therapy within 1 month of diagnosis resulted in consistently higher mixed-meal tolerance test-stimulated C-peptide values at all time points, although these differences were not statistically significant. Nonetheless, improved glycemic control was observed in insulin pump-treated subjects (more time spent with normoglycemia, better mean HbA1c), and pump-treated subjects reported comparatively greater satisfaction with route of treatment administration.

CONCLUSIONS

Initiation of insulin pump therapy at diagnosis improved glycemic control, was well tolerated, and contributed to improved patient satisfaction with treatment. This study also suggests that earlier use of pump therapy might help to preserve residual β-cell function, although a larger clinical trial would be required to confirm this.

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.