Continuous Glucose Monitoring to Measure Effect of Glycemic Index

The Effect of Glycemic Index on Post-prandial Glycemia (Breakfast vs. Lunch) in Patients With Type 1 Diabetes: Quantification With Continuous Glucose Monitoring

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.

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.

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 Glycemic Index.

Seven adult subjects with type 1 diabetes participated in two experiments, each consisting of two meals each. In one experiment, both meals had a high Glycemic Index.

A Dexcom Seven® Plus Continuous Glucose Monitoring sensor was inserted subcutaneously into each subject.

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.

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

Inclusion Criteria: clinical diagnosis of type 1 diabetes mellitus patients on insulin pump therapy 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.