Accuracy of Dexcom G6® and FreeStyle Libre® Sensors in Standardized Hypoxemia Conditions

June 16, 2026 updated by: Poitiers University Hospital

The major aim is to evaluate accuracy of 2 Continuous Glucose Monitoring Systems (CGMS) : Dexcom G6® and FreeStyle Libre® in standardized hypoxemia conditions (artificial normobaric hypoxia).

Our purpose is to demonstrate the good performance and calibration of these CGM sensors in hypoxemia conditions.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

30

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • France
      • Poitiers, France, 86000
        • CHU

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria: all population

  • No history of respiratory diseases (childhood asthma, respiratory allergies, exercise-induced asthma or dyspnea)
  • Willing to participate and able to sign an informed consent form (ICF)
  • Being affiliated with the French Social Security

Inclusion Criteria:Patients with diabetes

  • type 1 diabetes mellitus or type 2 diabetes mellitus (ADA definition)
  • Age : 18 to 75 years
  • stable diabetes treatment for more than 3 months
  • no diabetic retinopathy
  • no diabetic neuropathy
  • no cardiovascular diseases
  • no contra-indication for coronary computed tomography angiography or myocardial perfusion scintigraphy.

Inclusion Criteria: Healthy volunteers

  • Age : 18 ; 40 years
  • No diabetes
  • No persistant drug use > 3 months except contraception
  • Body mass index : [18,5 - 29,9] kg/m2

Non-inclusion criteria : all population

  • Active smokers
  • Pregnant or breastfeeding women, women of childbearing age without effective contraception
  • Known allergies to the patch.
  • Skin lesions at the sensor site that may interfere with sensor placement or accuracy
  • Major cardiovascular complications within the past 3 months
  • Decompensated congestive heart failure
  • Chronic respiratory failure
  • Chronic renal failure
  • Resting ambient air O2 saturation ≤95%.
  • Treatment with systemic corticosteroids
  • Severe hypertension (≥180 mmHg systolic pressure or ≥ 100 mmHg diastolic pressure)
  • Any concomitant disease or condition that the investigator believes may compromise patient safety or affect the conduct of the study
  • Anemia (Hb<12g/dl)
  • History of severe mountain sickness
  • Concurrent participation in another clinical research study,
  • Persons benefiting from enhanced protection

Non-inclusion criteria: Patients with diabetes

  • Absolute contraindications to physical activity (HAS definitin) :
  • Pulmonary arterial hypertension (> 60 mm Hg)
  • Presence of intra-cardiac thrombus
  • Acute pericardial effusion
  • Severe obstructive cardiomyopathy
  • Symptomatic aortic stenosis
  • Recent thrombophlebitis with or without pulmonary embolism

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: group 1 : FreeStyle Libre 2 on right arm and Dexcom G6 on left arm
In this group, participants will be continuously monitored for their interstitial glucose level with 2 CGM devices : FreeStyle Libre 2 will be applied on right arm and Dexcom G6 will be applied on left arm.
Procedure: acute hypoxia
Participants will be exposed to a 3-hour acute hypoxia
Active Comparator: group 2 : 2 FreeStyle Libre 2 on left arm and Dexcom G6 on right arm
In this group, participants will be continuously monitored for their interstitial glucose level with 2 CGM devices : Dexcom G6 will be applied on right arm and FreeStyle Libre 2 will be applied on left arm.
Procedure: acute hypoxia
Participants will be exposed to a 3-hour acute hypoxia

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mean Absolute Relative Difference (MARD)
Time Frame: Day 1
The primary endpoint for measuring the accuracy of CGMs (individually) compared to venous blood glucose was the mean absolute relative difference, expressed as a percentage. As the percentages obtained did not follow a normal distribution, they are expressed in the table as median and IQR.
Day 1

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Safety of acute hypoxia
Time Frame: Day 1
Arterial blood oxygen saturation (Sp02)
Day 1
Tolerability of acute hypoxia
Time Frame: Day 1
Lake Louise Questionnaire
Day 1

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Poitiers University Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 16, 2022

Primary Completion (Actual)

January 28, 2025

Study Completion (Actual)

January 28, 2025

Study Registration Dates

First Submitted

October 29, 2021

First Submitted That Met QC Criteria

November 30, 2021

First Posted (Actual)

December 3, 2021

Study Record Updates

Last Update Posted (Actual)

June 17, 2026

Last Update Submitted That Met QC Criteria

June 16, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • FOX

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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