A Trial Comparing Continuous Glucose Monitoring With and Without Routine Blood Glucose Monitoring in Adults With Type 1 Diabetes (REPLACE-BG)

This is an interventional supportive care trial for Type 1 Diabetes focused on measuring Diabetes Mellitus, Continuous Glucose Monitoring Read More

Inclusion Criteria:

To be eligible, all participants must meet the following inclusion criteria:

1. Clinical diagnosis of type 1 diabetes (based on investigator's judgment)
2. Age >=18 years
3. T1D duration >=1
4. HbA1c <=9.0% (a local laboratory or DCA2000 or comparable point of care device will be used to assess eligibility)
5. Use of an insulin pump for insulin delivery for at least 3 months, with no plans to discontinue pump use during the next 8 months
6. Participant is able to manage his/her diabetes with respect to insulin administration and glucose monitoring, as assessed by the investigator during the screening visit
7. Participant understands the study protocol and agrees to comply with it, including willingness to use the study CGM and BGM
8. No expectation that participant will be moving out of the area of the clinical center during the time period of the study, unless the move will be to an area served by another study center

Exclusion Criteria:

Individuals who meet any of the following criteria are not eligible for the study:

1. Severe hypoglycemia in the last 12 months in which the assistance of another individual was needed or seizure/loss of consciousness in the past 3 years

2. Significant hypoglycemia unawareness based on the Clarke Hypoglycemia Unawareness Survey defined as at least one of the following being present:

   • Survey score >2
   • Survey Q1 is answered as 'I no longer have symptoms when my blood sugar is low'
   • Survey Q7 response indicates that symptoms of hypoglycemia are not felt until glucose level is <50 mg/dl
   • Survey Q8 response is never or rarely to the question 'to what extent can you tell by your symptoms that your blood sugar is low'
3. More than one DKA event in the past year
4. History of seizures other than due to hypoglycemia
5. Current use of a threshold suspend pump feature (note: participant is eligible if a pump with this feature was being used but the threshold suspend was not active)
6. Myocardial infarction or stroke in past 6 months
7. Estimated Glomerular Filtration Rate (GFR) <30 obtained within the prior 12 months as part of usual care or kidney transplant
8. Most recent thyroid function test results abnormal, obtained as part of usual care within the prior 2 years
9. The presence of a significant medical or psychiatric disorder or use of a medication that in the judgment of the investigator will affect the wearing of the sensors, the completion of any aspect of the protocol, or increase risk
10. Cognitive difficulties that, in the judgment of the investigator, could impair the individual's ability to follow the protocol or increase risk
11. Initiation of a non-insulin drug for glucose control during the past 3 months, planned initiation during the next 8 months, or discontinuation of a non-insulin drug for glucose control during the past 3 months (note: individuals using a non-insulin medication for glucose control for 3 or more months are eligible provided there is no expectation that the medication will be discontinued during the time period of study participation)
12. Use of a systemic beta blocker drug
13. Regular use of oral corticosteroids
14. Anticipated need to use acetaminophen during the time course of the study
15. Inpatient psychiatric treatment in the past 6 months

16. Currently pregnant or lactating or plan to attempt getting pregnant during the time period of the study

    • Females with child-bearing potential will be queried about the possibility of pregnancy and a urine pregnancy test will be performed if there is uncertainty as to the possibility of pregnancy. They must agree to use appropriate birth control during the time period of the study. Participants will receive education regarding birth control methods which may be considered as highly effective, which are methods that can achieve a failure rate less than 1% per year when used consistently and correctly and include:

    • Combined hormonal contraception associated with inhibition of ovulation (oral, intravaginal, transdermal)
    • Progestogen-only hormonal contraception associated with inhibition of ovulation (oral, injectable, implantable)
    • Intrauterine device (IUD)
    • Intrauterine hormone-releasing system (IUS)
    • Bilateral tubal occlusion
    • Vasectomised partner
    • Sexual abstinence
17. Participation in an intervention study (including psychological studies) in past 6 weeks
18. Known adhesive allergy
19. From the blinded run-in phase (or from pre-study CGM use if criteria met to skip the blinded run-in phase), CGM values <60 mg/dl for more than 10.0% of the time
20. Unsuccessful completion of the run-in phases with respect to CGM or BGM use