Microvascular Insulin Resistance and Mixed Meal Challenge

• Sponsor: Menzies Institute for Medical Research (Other)
• Overall Status: Active, not recruiting
• CT.gov ID: NCT02708875
• Collaborator: Deakin University (Other)
• Enrollment: 45
• Locations: 2
• Arms: 2
• Anticipated Duration (Months): 88
• Patients Per Site: 22.5
• Patients Per Site Per Month: 0.3

Study Details

Study Description

Brief Summary

Insulin resistance (or pre-diabetes) is diagnosed using the oral glucose tolerance test. However, high blood glucose levels during this test may adversely impact on microvascular function. Investigators will determine whether a liquid mixed meal challenge (from carbohydrate, protein and fat) is a more appropriate test for assessing microvascular-derived insulin resistance.

Condition or Disease	Intervention/Treatment	Phase
Insulin Resistance	Other: Mixed Meal Challenge; Other: Glucose Challenge	N/A

Detailed Description

After consuming a meal, 80% of glucose is disposed in skeletal muscle. Our research group has demonstrated that microvascular blood flow in skeletal muscle plays an integral role in this process. Physiological doses of insulin stimulate microvascular blood flow, and that this increase is associated with enhanced glucose uptake by muscle. This microvascular action of insulin is lost during insulin resistance and type 2 diabetes.

The oral glucose tolerance test (GTT) is the gold standard for assessing insulin resistance and pre-diabetes and is used world-wide. However high blood glucose levels following a glucose load may adversely impact on microvascular function. The aim of this project is to determine whether a mixed meal challenge (liquid drink consisting of carbohydrate, fat and protein) is a better test for assessing microvascular-derived insulin resistance.

Study Design

• Study Type: Interventional
• Anticipated Enrollment: 45 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Masking: None (Open Label)
• Primary Purpose: Screening
• Official Title: Microvascular Insulin Resistance and Mixed Meal Challenge
• Actual Study Start Date: Aug 1, 2014
• Anticipated Primary Completion Date: Dec 1, 2021
• Anticipated Study Completion Date: Dec 1, 2021

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Mixed Meal Challenge Participants will consume a liquid mixed meal (~300 calories - fat, carbohydrate, and protein) for monitoring changes in glucose metabolism, plasma insulin and microvascular responses in skeletal muscle over 2 hours.	Other: Mixed Meal Challenge; Liquid mixed meal (300 calories - fat, carbohydrate, and protein).
Active Comparator: Glucose Challenge Participants will consume a glucose challenge (50g glucose) for monitoring changes in glucose metabolism, plasma insulin and microvascular responses in skeletal muscle over 2 hours.	Other: Glucose Challenge; Glucose drink (50g glucose)

Outcome Measures

Primary Outcome Measures

1. Change from baseline in muscle microvascular blood flow [1 hr]

   Microvascular responses will be measured by contrast enhanced ultrasound before and 1hr after each challenge.

Secondary Outcome Measures

1. Changes in blood glucose levels [2 hr]

   Blood glucose levels will be measured at 0, 15, 30, 60, 90 and 120 min following each challenge.

2. Changes in plasma insulin levels [2hr]

   Plasma insulin levels will be measured at 0, 15, 30, 60, 90 and 120 min following each challenge.

3. Changes in the respiratory exchange ratio (RER) [1 hr]

   Changes in RER will be measured by metabolic cart during each challenge.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 70 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

• Aged 18-70 years.

• Normal to overweight (BMI 19-35 kg/m2).

• Normotensive (Seated brachial blood pressure <160/100 mmHg).

• Considered healthy (HbA1c <6.5 %) or have clinically diagnosed type 2 diabetes.

• Either have a parent with T2D, or no family history of type 2 diabetes for two generations.

• Have given signed informed consent to participate in the study

Exclusion Criteria:

• Age <18 yrs or >70 yrs

• Morbidly obese with a BMI ≥36 kg/m2

• History of myocardial infarction or stroke

• History of malignancy within past 5 years (except for non-melanoma skin cancers)

• Current smoker

• History of severe liver disease

• History of drug or alcohol abuse

• Elective major surgery during the course of the study

• Pregnancy/lactation

• Participation or intention to participate in another clinical research study during the study period.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Menzies Institute for Medical Research	Hobart	Tasmania	Australia	7000
2	Deakin University	Burwood	Victoria	Australia	3125

Sponsors and Collaborators

• Menzies Institute for Medical Research
• Deakin University

Investigators

• Principal Investigator: Michelle A Keske, PhD, Menzies Institute for Medical Research

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Michelle Keske, Senior Research Fellow, Menzies Institute for Medical Research
• ClinicalTrials.gov Identifier: NCT02708875
• Other Study ID Numbers: H14086
• First Posted: Mar 15, 2016
• Last Update Posted: Apr 6, 2021
• Last Verified: Apr 1, 2021

• Individual Participant Data (IPD) Sharing Statement: No
• Plan to Share IPD: No
• Keywords provided by Michelle Keske, Senior Research Fellow, Menzies Institute for Medical Research: Microvascular; Insulin resistance; Mixed Meal; Glucose tolerance
• Additional relevant MeSH terms: Insulin Resistance

Study Results

No Results Posted as of Apr 6, 2021