Effect of Different Plasma Insulin Levels on the Accuracy of Continuous Subcutaneous Glucose Monitoring

Summary

Achieving near-normoglycaemia has been established as the main objective for most patients with diabetes. However, it is well known that intensification of treatment is associated with an increase in the frequency of hypoglycemia, especially in the context of insulin therapy. The burden of hypoglycemia in terms of psychological implications, morbidity and even mortality, explains why it has been defined as the main limiting factor to achievement of good metabolic control.

Continuous subcutaneous glucose monitoring (CGM) devices have been claimed to be useful in hypoglycemia detection/prevention, allowing theoretically for safer intensification of therapy in diabetic patients. However, accuracy of CGM devices, especially in the hypoglycemic range, raises some concerns. In fact, commercially available CGM devices estimate plasma glucose from measurements in the interstitial fluid and not in plasma. However, the relationship between plasma and interstitial glucose is not fully understood, especially under dynamic conditions, and this may explain the poor CGM performance during rapid changes in blood glucose and hypoglycemia.

In this project, the relationship between plasma and interstitial glucose will be evaluated under conditions of normal glucose concentrations and hypoglycemia. Experiments will be performed to assess the role, if any, of different plasma insulin concentrations on the accuracy of CGM.

All the information obtained may be relevant to the improvement of the ability of CGM devices to detect hypoglycemia and hypoglycemic risk.

Conditions

• Type 1 Diabetes
• Continuous Glucose Monitoring
• Hypoglycemia

Interventions

OTHER

High insulin eu-hypoglycemic clamp

Primed intravenous insulin infusion at a rate of 1mU/kg/min is given during the whole study duration. Glucose is infused at a variable rate to maintain plasma glucose concentrations 'clamped' at pre-specified levels. Plasma glucose levels will be the same in both study arms.

OTHER

Low insulin eu-hypoglycemic clamp

Primed intravenous insulin infusion at a rate of 0.3mU/kg/min is given during the whole study duration. Glucose is infused at a variable rate to maintain plasma glucose concentrations 'clamped' at pre-specified levels. Plasma glucose levels will be the same in both study arms.

Sponsors & Collaborators

• Universitat Politècnica de València

  collaborator OTHER

• Fundación para la Investigación del Hospital Clínico de Valencia

  lead OTHER

Principal Investigators

• Francisco Javier Ampudia-Blasco, MD, PhD · Hospital Clínico Universitario de Valencia - Fundación INCLIVA

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

DOUBLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

60 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2011-10-31

Primary Completion

2012-09-30

Completion

2012-10-31

Countries

• Spain

Study Locations