NCT02866435

Identifying the Brain Substrates of Hypoglycemia Unawareness in Type 1 Diabetes

• Status: Completed
• Phase: EARLY_Phase 1
• Study type: Interventional
• Enrollment: 27 (actual)
• Sponsor: University of Minnesota · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Accepted

Summary

The purpose of this study is to investigate how the brain responds to low blood glucose in non-diabetic individuals. The ultimate goal is to understand the brain substrates of hypoglycemia unawareness, a condition that can occur in patients with type1 diabetes undergoing insulin treatment.In the present study, the investigators focus on differences between two groups of non-diabetic subjects: one group who experienced two episodes of hypoglycemia the day prior to the study (and supposedly developed some level of unawareness to hypoglycemia), and one group who did not. In this study, a 3 tesla MRI scanner is used to acquire brain images. The imaging system is identical to the ones used in hospitals.

Detailed description

Hypoglycemia, also called low blood glucose or low blood sugar, occurs when blood glucose drops below normal levels. When blood glucose starts to drop, the body reacts to this drop, trying to restore the blood glucose level. Symptoms of hypoglycemia are usually easily recognized. Hypoglycemia can be treated quickly and easily by eating or drinking a small amount of glucose-rich food. However some people with long history of diabetes can have an impaired response to hypoglycemia and therefore don't recognize the symptoms of hypoglycemia, condition called hypoglycemia unawareness. If not treated hypoglycemia can get worse and cause confusion, clumsiness, fainting etc. Currently, it is not fully understood which brain areas are involved in sensing the drop of glucose levels. Absence of such knowledge is a critical barrier to the design and monitoring of effective intervention strategies to avoid and/or reverse hypoglycemia unawareness. The purpose of this study is to investigate how the brain responds to low blood glucose in non-diabetic individuals. Specific focus is given to differences between two groups of non-diabetic subjects: one group who experienced two episodes of hypoglycemia the day prior to the study (and therefore supposedly developed some level of unawareness to hypoglycemia), and one group who did not.

Conditions

• Hypoglycemia

Interventions

Type	Name	Description
DRUG	Insulin	In each clamp, a small intravenous catheter is placed in participant's arm for infusion of insulin together with potassium phosphate and glucose. Insulin is a hormone that body makes naturally and it causes blood sugar to decrease. Insulin (and glucose) will be infused in calculated doses to maintain blood sugar level in the target range of 95 mg/dl or 50 mg/dl depending on the clamp.
DRUG	Glucose	Glucose is administered together with insulin and potassium phosphate during each clamp via the intravenous catheter. Glucose is a sugar and it is used to carefully regulate blood sugar level.
DRUG	Potassium phosphate	Potassium phosphate is administered together with glucose and insulin during each clamp via the intravenous catheter. Potassium is a salt-like substance that is present in the blood.

Timeline

• Start date: 2016-11-01
• Primary completion: 2019-09-30
• Completion: 2019-12-30
• First posted: 2016-08-15
• Last updated: 2021-02-01

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study