The Multi-Sensor Distance Accuracy Study

NCT ID: NCT02241993

Last Updated: 2014-09-16

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 20 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2010-07-31
• Study Completion Date: 2011-01-31

Brief Summary

The purpose of the study is to test the accuracy benefit of having two glucose sensors (over one sensor alone) when they are positioned: 2mm, 10mm, 20mm, or 30mm apart. It is not yet known how close two sensors can be and still work correctly.

Detailed Description

An artificial pancreas system will likely require multiple glucose sensing elements to function safely. It is not yet known how close two glucose sensors can be placed and still work properly. Meaning, if one is reading inaccurately,and the other is positioned adjacent to it, will it read inaccurately also, defeating the purpose of having two sensors. Twenty adult subjects with Type 1 diabetes will wear four Medtronic REAL-Time glucose sensors during two separate 10-hour studies. The inter-sensor distances of each pair to be tested will be: 2, 10, 20, and 30mm apart. The sensors will be inserted the day prior to the study day to allow for signal stabilization and calibration. During the study day, arterialized venous blood will be drawn every 15 minutes to measure blood glucose. The sensor values and interstitial values will be recorded from each sensor receiver at each time point. Subjects will be fed two standardized meals and given pre-meal insulin based on their typical insulin to carbohydrate ratio.

Conditions

Type 1 Diabetes Mellitus

Study Design

• Observational Model Type: CASE_ONLY
• Study Time Perspective: PROSPECTIVE

Study Groups

Type 1 diabetic

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

1. Type 1 diabetes mellitus diagnosed for at least 6 months

2. Current usage of multiple daily injections or subcutaneous insulin pump treatment

3. Age 18-65 years

4. HbA1c of 6.0 - 9.5% at screening visit

5. BMI 21-35

6. Willingness to follow all study procedures, including attending all clinic visits

7. Willingness to sign informed consent and HIPAA documents

Exclusion Criteria

1. Pregnancy or Lactation: for women of childbearing potential there is a requirement for a negative urine pregnancy test.

2. Renal insufficiency (serum creatinine of 2.0 mg/dL or greater). Serum ALT or AST equal to or greater than 3 times the upper limit of normal; hepatic synthetic insufficiency as defined as a serum albumin of less the 3.3 g/dL; or serum bilirubin of over 2.

3. Hematocrit of less than or equal to 34%.

4. Congestive heart failure, NYHA class III or IV.

5. Visual impairment preventing reading of glucose meter values.

6. Active coronary artery disease as manifested by unstable angina, or a myocardial infarction or therapeutic coronary percutaneous procedure (e.g., PTCA, stent placement) or CABG within the past 4 months.

7. Active foot ulceration.

8. Severe peripheral arterial disease characterized by ischemic rest pain or severe claudication.

9. Cerebrovascular accident within the past 6 months.

10. Active alcohol abuse, substance abuse, or severe mental illness (as judged by the principal investigator).

11. Active malignancy, except basal cell or squamous cell skin cancers.

12. Major surgical operation within 30 days prior to screening.

13. Seizure disorder (epilepsy).

14. Any concurrent illness, other than diabetes, that is not controlled by a stable therapeutic regimen.

15. Currently administration of oral or parenteral corticosteroids.

16. Use of an investigational drug within 30 days prior to screening.

17. Bleeding disorder, treatment with warfarin, or platelet count below 50,000.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

The Leona M. and Harry B. Helmsley Charitable Trust

OTHER

Sponsor Role: collaborator

Oregon Health and Science University

OTHER

Sponsor Role: lead

Responsible Party

W Kenneth Ward MD

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

W. Kenneth Ward, MD

Role: PRINCIPAL_INVESTIGATOR

Oregon Health and Science University

Locations

Oregon Health & Science University

Portland, Oregon, United States

Countries

United States

References

Ward WK, Casey HM, Quinn MJ, Federiuk IF, Wood MD. A fully implantable subcutaneous glucose sensor array: enhanced accuracy from multiple sensing units and a median-based algorithm. Diabetes Technol Ther. 2003;5(6):943-52. doi: 10.1089/152091503322640980.

Reference Type: BACKGROUND

PMID: 14709196 (View on PubMed)

Schmidtke DW, Pishko MV, Quinn CP, Heller A. Statistics for critical clinical decision making based on readings of pairs of implanted sensors. Anal Chem. 1996 Sep 1;68(17):2845-9. doi: 10.1021/ac9602027.

Reference Type: BACKGROUND

PMID: 8794921 (View on PubMed)

Castle JR, Engle JM, El Youssef J, Massoud RG, Yuen KC, Kagan R, Ward WK. Novel use of glucagon in a closed-loop system for prevention of hypoglycemia in type 1 diabetes. Diabetes Care. 2010 Jun;33(6):1282-7. doi: 10.2337/dc09-2254. Epub 2010 Mar 23.

Reference Type: RESULT

PMID: 20332355 (View on PubMed)

Other Identifiers

11619

Identifier Type: -

Identifier Source: org_study_id