Clinical Trial Details
— Status: Active, not recruiting
Administrative data
| NCT number |
NCT04533646 |
| Other study ID # |
STUDY20060197 |
| Secondary ID |
|
| Status |
Active, not recruiting |
| Phase |
Phase 4
|
| First received |
|
| Last updated |
|
| Start date |
March 17, 2021 |
| Est. completion date |
December 1, 2024 |
Study information
| Verified date |
October 2023 |
| Source |
University of Pittsburgh |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial 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.
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.
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.
Hypothesis:
1. 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
2. Participants who utilize carbohydrate counting will have fewer hypoglycemia events
compared to participants who use fixed-dose meal-time insulin
Specific Aims:
1. 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.
2. 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.
3. To test the use of 'rule of 500' for carb counting estimation in patients with CFRD
4. To compare the effect of two methods of rapid-acting insulin delivery on fasting
glycemia
