In a multicenter, randomized, crossover trial involving children 1 to 7 years of age with type 1 diabetes, a closed-loop system was compared with sensor-augmented pump therapy in random order. The ...closed-loop system improved glycemic control in very young children with type 1 diabetes, without increasing the time spent in a hypoglycemic state.
Measurement of glycated hemoglobin (HbA
) has been the traditional method for assessing glycemic control. However, it does not reflect intra- and interday glycemic excursions that may lead to acute ...events (such as hypoglycemia) or postprandial hyperglycemia, which have been linked to both microvascular and macrovascular complications. Continuous glucose monitoring (CGM), either from real-time use (rtCGM) or intermittently viewed (iCGM), addresses many of the limitations inherent in HbA
testing and self-monitoring of blood glucose. Although both provide the means to move beyond the HbA
measurement as the sole marker of glycemic control, standardized metrics for analyzing CGM data are lacking. Moreover, clear criteria for matching people with diabetes to the most appropriate glucose monitoring methodologies, as well as standardized advice about how best to use the new information they provide, have yet to be established. In February 2017, the Advanced Technologies & Treatments for Diabetes (ATTD) Congress convened an international panel of physicians, researchers, and individuals with diabetes who are expert in CGM technologies to address these issues. This article summarizes the ATTD consensus recommendations and represents the current understanding of how CGM results can affect outcomes.
Parameters of physiological models of glucose-insulin regulation in type 1 diabetes have previously been estimated using data collected over short periods of time and lack the quantification of ...day-to-day variability. We developed a new hierarchical model to relate subcutaneous insulin delivery and carbohydrate intake to continuous glucose monitoring over 12 weeks while describing day-to-day variability. Sensor glucose data sampled every 10-min, insulin aspart delivery and meal intake were analyzed from eight adults with type 1 diabetes (male/female 5/3, age 39.9 ± 9.5 years, BMI 25.4 ± 4.4kg/m 2 , HbA1c 8.4 ± 0.6% ) who underwent a 12-week home study of closed-loop insulin delivery. A compartment model comprised of five linear differential equations; model parameters were estimated using the Markov chain Monte Carlo approach within a hierarchical Bayesian model framework. Physiologically, plausible a posteriori distributions of model parameters including insulin sensitivity, time-to-peak insulin action, time-to-peak gut absorption, and carbohydrate bioavailability, and good model fit were observed. Day-to-day variability of model parameters was estimated in the range of 38-79% for insulin sensitivity and 27-48% for time-to-peak of insulin action. In conclusion, a linear Bayesian hierarchical approach is feasible to describe a 12-week glucose-insulin relationship using conventional clinical data. The model may facilitate in silico testing to aid the development of closed-loop insulin delivery systems.
The artificial pancreas Boughton, Charlotte K; Hovorka, Roman
Current opinion in organ transplantation,
08/2020, Letnik:
25, Številka:
4
Journal Article
Advances in diabetes technologies have enabled the development of artificial pancreas (closed-loop) systems for people with diabetes. We review the key studies which have led to the adoption of the ...artificial pancreas in clinical practice and consider ongoing challenges and areas for future enhancements.
Studies have demonstrated safety and efficacy of closed-loop insulin delivery systems in free-living settings over periods of up to 6 months for children and adults with type 1 diabetes. Since 2017, four hybrid closed-loop systems have been approved by regulatory bodies worldwide, but these systems are not entirely automated, requiring user interaction to deliver mealtime insulin boluses. Improving usability of these devices in the real-world setting is an important challenge.
The artificial pancreas has become the gold standard for the treatment of type 1 diabetes. First-generation systems are increasingly being adopted in clinical practice, however further work is required, developing advanced systems and faster acting insulin analogues to allow complete automation and further reduce the burden of type 1 diabetes.
Rapid progress over the past decade has been made with the development of the 'Artificial Pancreas', also known as the closed-loop system, which emulates the feedback glucose-responsive functionality ...of the pancreatic beta cell. The recent FDA approval of the first hybrid closed-loop system makes the Artificial Pancreas a realistic therapeutic option for people with type 1 diabetes. In anticipation of its advent into clinical care, we provide a primer and appraisal of this novel therapeutic approach in type 1 diabetes for healthcare professionals and non-specialists in the field.
Randomised clinical studies in outpatient and home settings have shown improved glycaemic outcomes, reduced risk of hypoglycaemia and positive user attitudes. User input and interaction with existing closed-loop systems, however, are still required. Therefore, management of user expectations, as well as training and support by healthcare providers are key to ensure optimal uptake, satisfaction and acceptance of the technology. An overview of closed-loop technology and its clinical implications are discussed, complemented by our extensive hands-on experience with closed-loop system use during free daily living.
The introduction of the artificial pancreas into clinical practice represents a milestone towards the goal of improving the care of people with type 1 diabetes. There remains a need to understand the impact of user interaction with the technology, and its implication on current diabetes management and care.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
BACKGROUND: Accuracy and frequency of glucose measurement is essential to achieve safe and efficacious glucose control in the intensive care unit. Emerging continuous glucose monitors provide ...frequent measurements, trending information, and alarms. The objective of this study was to establish the level of accuracy of continuous glucose monitoring (CGM) associated with safe and efficacious glucose control in the intensive care unit. METHODS: We evaluated 3 established glucose control protocols Yale, University of Washington, and Normoglycemia in Intensive Care Evaluation and Surviving Using Glucose Algorithm Regulation (NICE-SUGAR) by use of computer simulations. Insulin delivery was informed by intermittent blood glucose (BG) measurements or CGM levels with an increasing level of measurement error. Measures of glucose control included mean glucose, glucose variability, proportion of time glucose was in target range, and hypoglycemia episodes. RESULTS: Apart from the Washington protocol, CGM with mean absolute relative deviation (MARD) less than or equal to I5% resulted in similar mean glucose as with the use of intermittent BG measurements. Glucose variability was also similar between CGM and BG-informed protocols. Frequency and duration of hypoglycemia were not worse by use of CGM with MARD less than or equal to 10%. Measures of glucose control varied more between protocols than at different levels of the CGM error. CONCLUSIONS: The efficacy of CGM-informed and BG-informed commonly used glucose protocols is similar, but the risk of hypoglycemia may be reduced by use of CGM with MARD less than or equal to 10%. Protocol choice has greater influence on glucose control measures than the glucose measurement method.
Aims:
Closed-loop insulin delivery has the potential to improve day-to-day glucose control in type 1 diabetes pregnancy. However, the psychosocial impact of day-and-night usage of automated ...closed-loop systems during pregnancy is unknown. Our aim was to explore women’s experiences and relationships between technology experience and levels of trust in closed-loop therapy.
Methods:
We recruited 16 pregnant women with type 1 diabetes to a randomized crossover trial of sensor-augmented pump therapy compared to automated closed-loop therapy. We conducted semistructured qualitative interviews at baseline and follow-up. Findings from follow-up interviews are reported here.
Results:
Women described benefits and burdens of closed-loop systems during pregnancy. Feelings of improved glucose control, excitement and peace of mind were counterbalanced by concerns about technical glitches, CGM inaccuracy, and the burden of maintenance requirements. Women expressed varied but mostly high levels of trust in closed-loop therapy.
Conclusions:
Women displayed complex psychosocial responses to day-and-night closed-loop therapy in pregnancy. Clinicians should consider closed-loop therapy not just in terms of its potential impact on biomedical outcomes but also in terms of its impact on users’ lives.
In two randomized trials conducted under home conditions, investigators compared closed-loop insulin delivery with sensor-augmented pump therapy in adults and in children and adolescents for 12 ...weeks. The closed-loop approach improved glucose control and reduced hypoglycemia.
Intensive insulin therapy is the standard of care for type 1 diabetes but is limited by the risk of hypoglycemia,
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which leads to failure in achieving treatment goals for most patients in all age groups.
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Among patients with type 1 diabetes, hypoglycemia is common, has a major effect on patients’ quality of life and psychological well-being,
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and may cause seizures, which is of particular concern during the overnight hours in children and adolescents.
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New approaches (e.g., continuous glucose monitoring) can improve glycemic control when the patient wears the sensors on a regular basis.
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If insulin delivery is linked . . .
OBJECTIVE:--To assess whether prandial insulin, in addition to basal insulin, has an effect on the rate of glucose appearance from a meal in people with type 1 diabetes. RESEARCH DESIGN AND ...METHODS--The rate of glucose appearance from a mixed meal (Rameal) was investigated in six adult (aged 24 ± 2 years), lean (BMI 23.6 ± 1.5 kg/m²) subjects with well-controlled type 1 diabetes (duration 7.9 ± 6.9 years, A1C 7.6 ± 0.9%) with/without prandial insulin. Actrapid was infused to maintain euglycemia before meals were consumed. Subjects consumed two identical meals on separate occasions, and Rameal was measured using a dual isotope method. 6,6-²H₂glucose was incorporated into the meal (0.081 g/kg body wt), and a primed constant/variable rate infusion of 1,2,3,4,5,6,6-²H₂glucose was administered. In the tests with prandial insulin, an additional bolus dose of Actrapid was given 20 min before the meal at 0.1 units/kg body wt. RESULTS:--Insulin concentration with prandial insulin was significantly higher than during basal insulin studies (119 ± 16 vs. 66 ± 15 pmol/l, P = 0.03 by paired t test). Despite differences in insulin concentration, there were no differences in total glucose appearance (3,398 ± 197 vs. 3,307 ± 343 μmol/kg) or time taken for 25% (33.1 ± 3.3 vs. 31.7 ± 3.5 min), 50% (54.6 ± 3.5 vs. 54.1 ± 4.7 min), and 75% (82.9 ± 7.1 vs. 82.8 ± 5.8 min) of total glucose appearance. The fraction of the glucose dose appearing in the circulation was the same for basal (73 ± 8%) and prandial (75 ± 4%) study days. CONCLUSIONS:--These results suggest that meal glucose appearance is independent of prandial insulin concentration in people with type 1 diabetes.
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