Comparison of Meal-Time Dosing of Insulin in Cystic Fibrosis Related Diabetes

Sponsor

Jagdeesh Ullal (Other)

Overall Status

Recruiting

CT.gov ID

NCT04533646

Collaborator

Wake Forest University Health Sciences (Other)

Enrollment

Location

Arm

22.5

Anticipated Duration (Months)

0.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The aim of this study is to assess the utility of CGMs to determine the optimal method to dose meal-time insulin. The investigators will examine glucose excursions in patients with CF who will dose meal-time rapid-acting insulin by carbohydrate counting versus fixed-dose rapid-acting insulin. The carbohydrate ratio and fixed doses will be determined by existing doses, total daily insulin doses, body weight, and insulin sensitivity along with predisposition to hypoglycemia. Bolus insulin dosing is an important part of CFRD management due to the high nutritional demands of these patients. If dosed incorrectly, this could lead to marked hyperglycemia and could worsen nutritional status due to urinary glucose losses. In this project, the investigators will perform a within-subjects' comparison of the 2 standard methods of meal-time rapid-acting insulin dosing.

Condition or Disease	Intervention/Treatment	Phase
Cystic Fibrosis-related Diabetes	Drug: Insulin Device: Continuous glucose monitor (CGM)	Phase 4

Detailed Description

Background and Introduction Cystic fibrosis-related diabetes (CFRD) is the most common extra-pulmonary comorbidity in patients with cystic fibrosis (CF). CFRD is also associated with an accelerated decline in pulmonary function, increased pulmonary exacerbations, and increased mortality. Continuous glucose monitoring (CGM) involves the use of a small disposable sensor sited in the subcutaneous interstitial fluid that makes frequent glucose measurements. There is data suggesting that the Medtronic iPro continuous glucose monitors (CGM) can predict hemoglobin a1c levels in patients with CFRD.

Hypothesis:

Postprandial interstitial fluid glucose levels in participants who utilize carbohydrate counting to dose mealtime rapid-acting insulin will have improved control as defined as the area under the curve and time in target compared to participants who used fixed-dose mealtime insulin
Participants who utilize carbohydrate counting will have fewer hypoglycemia events compared to participants who use fixed-dose meal-time insulin

Specific Aims:

To compare within-subject glucose excursions defined as the percentage of time in target glucose level, percentage of glucose in target, and peak postprandial glucose with fixed insulin dosing versus carbohydrate count based insulin dosing.
To compare the frequency and duration of hypoglycemia (defined as the daily, weekly, and average duration of the event) between insulin delivery methods described above.
To test the use of 'rule of 500' for carb counting estimation in patients with CFRD
To compare the effect of two methods of rapid-acting insulin delivery on fasting glycemia

Study Design

Study Type:

Interventional

Anticipated Enrollment :

20 participants

Allocation:

N/A

Intervention Model:

Single Group Assignment

Intervention Model Description:

This study design involves a within-subjects comparison using a sequential cross over that occurs over a 2-week time frame. During the first seven days of wear, the participants will be asked to dose their mealtime rapid-acting insulin by fixed-dose, and the next seven days, participants will be asked to dose their mealtime rapid-acting insulin by carbohydrate counting. After the 14 days, participants will return their continuous glucose monitor (CGM) devices for analysis and interpretation.This study design involves a within-subjects comparison using a sequential cross over that occurs over a 2-week time frame. During the first seven days of wear, the participants will be asked to dose their mealtime rapid-acting insulin by fixed-dose, and the next seven days, participants will be asked to dose their mealtime rapid-acting insulin by carbohydrate counting. After the 14 days, participants will return their continuous glucose monitor (CGM) devices for analysis and interpretation.

Masking:

None (Open Label)

Primary Purpose:

Treatment

Official Title:

Comparison of Meal-Time Dosing of Rapid Acting Insulin Using Carbohydrate Counting vs. Fixed Doses Utilizing Continuous Glucose Monitoring In Patients With Cystic Fibrosis Related Diabetes

Actual Study Start Date :

Mar 17, 2021

Anticipated Primary Completion Date :

Sep 1, 2022

Anticipated Study Completion Date :

Feb 1, 2023

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Fixed Dosing, Followed by Carbohydrate Counting Dosing of premeal insulin with fixed doses	Drug: Insulin Participants will be asked to dose insulin during the first week using fixed doses. During the second week of the study, participants will dose insulin based on carbohydrate counting. Blood sugar control will be compared between the 2 weeks to determine the outcomes of the study. Device: Continuous glucose monitor (CGM) Participants will be required to wear a CGM to measure glucose trends

Arm

Intervention/Treatment

Experimental: Fixed Dosing, Followed by Carbohydrate Counting

Dosing of premeal insulin with fixed doses

Drug: Insulin

Participants will be asked to dose insulin during the first week using fixed doses. During the second week of the study, participants will dose insulin based on carbohydrate counting. Blood sugar control will be compared between the 2 weeks to determine the outcomes of the study.

Device: Continuous glucose monitor (CGM)

Participants will be required to wear a CGM to measure glucose trends

Outcome Measures

Primary Outcome Measures

Time in Target [2 weeks]
Measurement of percentage of time in target of glucose level

Secondary Outcome Measures

Hypoglycemia number [2 weeks]
To determine the number of hypoglycemic events under 70 mg/dl
Hypoglycemia duration [2 weeks]
To determine the duration of hypoglycemic events in minutes

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 80 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Age >18 age of years
Diagnosis of cystic fibrosis related diabetes
Using basal bolus insulin
Cystic Fibrosis with Lung Transplantation

Exclusion Criteria:

Use of continuous glucose monitors
Patient unable to check fingerstick blood sugars

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	University of Pittsburgh Medical Center, Center for Diabetes and Endocrinology	Pittsburgh	Pennsylvania	United States	15213

Sponsors and Collaborators

Jagdeesh Ullal
Wake Forest University Health Sciences

Investigators

Principal Investigator: Jagdeesh Ullal, MD, University of Pittsburgh Medical Center

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

Jagdeesh Ullal, Clinical Associate Professor, University of Pittsburgh

ClinicalTrials.gov Identifier:

NCT04533646

Other Study ID Numbers:

STUDY20060197

First Posted:

Aug 31, 2020

Last Update Posted:

May 5, 2022

Last Verified:

May 1, 2022

Individual Participant Data (IPD) Sharing Statement:

Plan to Share IPD:

Studies a U.S. FDA-regulated Drug Product:

Yes

Studies a U.S. FDA-regulated Device Product:

Product Manufactured in and Exported from the U.S.:

Yes

Additional relevant MeSH terms:

Study Results

No Results Posted as of May 5, 2022