Identifying the Brain Substrates of Hypoglycemia Unawareness in Type 1 Diabetes

Hypoglycemia Clinical Trial

Official title:

Identifying the Brain Substrates of Hypoglycemia Unawareness in Type 1 Diabetes

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02866435
• Other study ID #: 1608M92941
• Status: Completed
• Phase: Early Phase 1
• Start date: November 2016
• Est. completion date: December 30, 2019

Study information

• Verified date: January 2021
• Source: University of Minnesota
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 27
• Est. completion date: December 30, 2019
• Est. primary completion date: September 30, 2019
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

Inclusion Criteria:

Participants will be included in the study, if they

• are non-diabetic

• are evaluated as not contraindicated (based on exclusion criteria)

• are age (within 5 years), gender, and body mass index (within 4 kg/m2) matched to patients with type 1 diabetes who have participated to a similar study which involved only the second part (day 2) of the current protocol.

Exclusion Criteria:

Participants will be excluded from the study, if they

• have any type of bio-implant activated by mechanical, electronic, or magnetic means (e.g. cochlear implants, pacemakers, neurostimulators, bio stimulators, electronic infusion pumps)

• have any type of ferromagnetic bio-implant that could potentially be displaced or damaged, such as aneurysm clips, metallic skull plates, etc

• have any retained metal in their body, either from a medical procedure or an injury

• have history of stroke, seizures, neurosurgical procedures, or arrhythmias

• are pregnant

• are currently using medication that can alter glucose metabolism or brain perfusion

• weight more than 300lbs (limit for MRI scanner)

• have concomitant medical problems that may prevent them from successfully completing the protocol

• lack capacity to consent

Related Conditions & MeSH terms

• Hypoglycemia

Intervention

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.
• 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.
• 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.

Locations

Country	Name	City	State
United States	University of Minnesota	Minneapolis	Minnesota

Sponsors (1)

Lead Sponsor	Collaborator
University of Minnesota

Country where clinical trial is conducted

United States, 

References & Publications (4)

Bolo NR, Musen G, Simonson DC, Nickerson LD, Flores VL, Siracusa T, Hager B, Lyoo IK, Renshaw PF, Jacobson AM. Functional Connectivity of Insula, Basal Ganglia, and Prefrontal Executive Control Networks during Hypoglycemia in Type 1 Diabetes. J Neurosci. 2015 Aug 5;35(31):11012-23. doi: 10.1523/JNEUROSCI.0319-15.2015. — View Citation

Mangia S, Tesfaye N, De Martino F, Kumar AF, Kollasch P, Moheet AA, Eberly LE, Seaquist ER. Hypoglycemia-induced increases in thalamic cerebral blood flow are blunted in subjects with type 1 diabetes and hypoglycemia unawareness. J Cereb Blood Flow Metab. 2012 Nov;32(11):2084-90. doi: 10.1038/jcbfm.2012.117. Epub 2012 Aug 15. — View Citation

Rooijackers HM, Wiegers EC, Tack CJ, van der Graaf M, de Galan BE. Brain glucose metabolism during hypoglycemia in type 1 diabetes: insights from functional and metabolic neuroimaging studies. Cell Mol Life Sci. 2016 Feb;73(4):705-22. doi: 10.1007/s00018-015-2079-8. Epub 2015 Oct 31. Review. — View Citation

Wiegers EC, Becker KM, Rooijackers HM, von Samson-Himmelstjerna FC, Tack CJ, Heerschap A, de Galan BE, van der Graaf M. Cerebral blood flow response to hypoglycemia is altered in patients with type 1 diabetes and impaired awareness of hypoglycemia. J Cereb Blood Flow Metab. 2017 Jun;37(6):1994-2001. doi: 10.1177/0271678X16658914. Epub 2016 Jan 1. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change from baseline (i.e., normal glucose levels) functional connectivity, measured as a dimensionless correlation coefficient of MRI signals among brain areas, at hypoglycemia	Functional connectivity will be measured with MRI at 3 Tesla	Baseline and immediately as hypoglycemia starts
Primary	Change from baseline (i.e., normal glucose levels) cerebral blood flow, measured in ml/min/100g, at hypoglycemia	Cerebral blood flow will be measured with MRI at 3 Tesla	Baseline and immediately as hypoglycemia starts

External Links

•   Description Profile of Principal Investigator