Continuous Glucose Monitoring to Measure Effect of Glycemic Index

Not Applicable

Completed

Brief Summary: Background: Post-prandial hyperglycemia is common in people with type 1 diabetes.

Objective: The aim was to determine the impact of low vs high glycemic index (GI) on post-prandial glycemia for breakfast vs lunch and to quantify these effects with continuous glucose monitoring.

Design: Seven adult subjects with type 1 diabetes participated in two experiments, each consisting of two meals each. In one experiment, both meals had a low GI; in the other, high GI. Meals were given 195 minutes apart and were matched for carbohydrate, protein, and fat content. Each subject received his usual pre-prandial insulin dosage, followed by a continuous subcutaneous basal insulin infusion for the remainder of the experiment. Arterialized venous glucose was analyzed every 15 minutes and sensor glucose was recorded every 5 minutes.

Detailed Description: A total of 14 diet studies (each with two meals) were completed in three men and four women. All subjects completed two diet studies in which two meals were served 195 minutes apart. On one study day, two high GI (\> 75) meals were given, and on the other study day, two low GI (\< 30) meals were given. The low GI and high GI meals were matched for amount of carbohydrates, protein, and fat based on a weight-maintaining diet for each subject. The order of the study treatment (high or low GI) was randomized. Subjects were not informed as the GI of any meal.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Any patient who was

pregnancy
cardiovascular, cerebrovascular, kidney, or liver disease
uncontrolled chronic medical conditions
oral or parenteral corticosteroid use
immunosuppressant use
visual or physical impairments that impede the use of a continuous glucose monitoring device
insulin or glucagon allergy
hypoglycemia unawareness
requirement of greater than 200 units of insulin per day
gastroparesis
any prior gastric surgery
an allergy to any food items served.

Primary Outcome Measures

Name	Time	Method
Mean Area Under the Curve for Rise in Breakfast Post-prandial.	Mean area under the curve was calculated at 0, 15min, 30 min, 45 min, 60min, 75 min, 90 min, 105 min, 120min, 135min, 150min, 165min and 180 min after breakfast	Arterialized blood glucose was monitored at 15 minute intervals and sensed glucose was recorded at five minute intervals. Mean area under the curve was calculated over the 3 hour period after breakfast for both the high and low glycemic breakfast meals.

Secondary Outcome Measures

Name	Time	Method

Locations (1): Legacy Health System--Holladay Park Campus
🇺🇸
Portland, Oregon, United States
Legacy Health System--Holladay Park Campus
🇺🇸Portland, Oregon, United States