Preventing Hypoglycemia During Exercise With Proactive Snacking on Closed Loop

Type 1 Diabetes Clinical Trial

Official title:

Preventing Hypoglycemia During Exercise With Proactive Snacking on Closed Loop

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02135068
• Other study ID #: 1403013588
• Secondary ID: T32DK063703
• Status: Completed
• Phase: Early Phase 1
• Start date: January 2015
• Est. completion date: December 2016

Study information

• Verified date: April 2020
• Source: Yale University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study is designed to look at how snacking during exercise may help prevent low blood sugars while subjects are on the "closed loop artificial pancreas." This system uses a continuous glucose sensor, an insulin pump, and a computer program that automatically determines how much insulin to give based on the sensor glucose level.

Description:

This study will be a randomized cross-over study as subjects will be studied under both study conditions - Closed Loop (CL) alone vs. CL + proactive snacking protocol). Differences in the nadir blood glucose levels during exercise between the two study conditions will be the primary outcome measure.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 15
• Est. completion date: December 2016
• Est. primary completion date: June 2016
• Accepts healthy volunteers: No
• Gender: All
• Age group: 13 Years to 44 Years

Eligibility

Inclusion Criteria:

1. Age 13-45 years

2. Clinical diagnosis of T1D (formal antibody and/or genetic testing will not be required)

3. Duration of T1D = 1 year

4. HbA1c = 9 %

5. Treated with continuous subcutaneous insulin infusion (pump) for at least 3 months

6. Body weight > 40 kg (to accommodate phlebotomy)

7. Able to tolerate a 75-minute exercise period of moderate intensity

8. Be willing to wear 2 subcutaneous glucose sensors (placed under the skin like a pump site) simultaneously during the inpatient portions of this study.

9. Be in good general health without other acute or chronic illness that in the judgment of the investigator could interfere with the study or jeopardize subject safety

10. Normal hematocrit

11. Able to give consent (for children <18 years, permission from parents and subject assent will be required)

12. Female subjects of reproductive potential must be abstinent or consistently using appropriate family planning methods.

Exclusion Criteria:

1. Insulin resistant (defined as requiring > 1.5 units/kg/day at time of study enrollment)

2. Presence of any medical or psychiatric disorder that may interfere with subject safety or study conduct

3. Use of any medications (besides insulin) known to effect blood glucose levels, including oral or other systemic glucocorticoid therapy. Inhaled, intranasal, or rectal corticosteroid use is allowed along as not given within 2 weeks of the closed loop admissions. Use of topical glucocorticoids is allowable as long as affected skin area does not overlap with study device sites.

4. Subjects using herbal supplements will be excluded, due to the unknown effects of these supplements on glucose control

5. History of hypoglycemic seizure within last 3 months

6. Female subjects who are pregnant, lactating, or unwilling to be tested for pregnancy

Related Conditions & MeSH terms

• Diabetes Mellitus, Type 1
• Hypoglycemia
• Type 1 Diabetes

Intervention

Device:
• Medtronic MiniMed Closed Loop (CL) System
The Medtronic MiniMed Closed Loop (CL) System is an investigational system that uses some commercially available products. An investigational Enlite 2 glucose sensor measures the sensor glucose. The glucose sensor signal is sent to the insulin pump. From the insulin pump the sensor glucose is sent through the translator, which then relays the signal on to a controller. An Android Mobile Device (off the shelf) has the control algorithm installed. This device is known as the controller. The controller serves as the control center for the Android system, receiving data from the sensor and pump components, feeding the data to its control algorithm, issuing delivery commands to the pump to apply the algorithm's recommend therapy, and providing a means to monitor the system.

Other:
• Snacking
Up to 45 g of oral glucose via Gatorade

Locations

Country	Name	City	State
United States	Yale University School of Medicine	New Haven	Connecticut

Sponsors (2)

Lead Sponsor	Collaborator
Yale University	National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Nadir blood glucose levels during exercise	Difference in the nadir blood glucose levels during exercise between the two study conditions: Closed Loop alone vs. Closed Loop+ snacking.	75 minutes
Secondary	Episodes of hypoglycemia (blood glucose <60mg/dL) during exercise	Percentage of subjects that required treatment for hypoglycemia during the exercise period between the two study conditions	75 minutes
Secondary	Mean reduction in blood glucose during exercise	Mean Reduction in blood glucose from baseline blood glucose during exercise	75 minutes
Secondary	Mean time blood glucose in target during exercise	Comparison of the mean time blood glucose levels were between 70-180mg/dL during exercise between the two study conditions	75 minutes
Secondary	Mean time blood glucose levels are in target during the overnight period	Comparison of the mean time blood glucose levels are in target (70-180mg/dL) during the overnight period after mid-afternoon exercise.	17 hours
Secondary	Mean glucose values	Comparison of the mean daytime and nighttime glucose values	12 hours
Secondary	Mean 24- hour glucose levels	Comparison of the mean 24- hour glucose levels	24 hours
Secondary	insulin delivery during CL therapy	Differences between insulin delivery during CL therapy during the two study conditions (pro-active snacking vs. no snacking) will be assessed.	24 hours
Secondary	Incremental meal-related glucose Area Under the Curve	Assessment of incremental meal related glucose area under the curve will be conducted.	24 hours
Secondary	Nadir glucose levels following the meals	Nadir glucose levels following meals will be compared between the two study conditions	24 hours
Secondary	Area under the curve meal-related plasma insulin level excursion following meals	Area under the curve meal-related insulin excursion following meals.	24 hours
Secondary	Nadir glucose levels overnight	Difference between nadir glucose levels between the two study conditions will be assessed.	12 hours
Secondary	Mean absolute relative difference (MARD) for each sensor	Calculation and comparison of the mean absolute relative difference for each sensor will be performed and comparisons between accuracy of the sensors will be done.	24 hours
Secondary	Mean daytime and nighttime glucose values	Comparison of the mean daytime and nighttime glucose levels	24 hours