None listed
Conditions
Brief summary
Mealtime insulin dosing for type 1 diabetes is a challenging area of practice. Current insulin dosing adjusts the insulin amount dependent on the carbohydrate content of the meal (carbohydrate counting [CC]). Meals high in protein, fat and protein and fat have all been shown to increase postprandial glycaemia. Novel insulin algorithms have been developed to account for the glycaemic effect of fat and protein: Food insulin index (FII) and Pankowska Equation (PE). Our study aimed to compare glycaemic outcomes for CC, FII and PE for a high protein and a high fat meal. Outcomes chosen included postprandial glucose excursions for 300 minutes following the test meal, postprandial blood glucose levels for 300 minutes following the test meal, percentage of time within target range (3.9-10mmol/L) and hypoglycaemic events.
Interventions
3 different insulin dosing algorithms will be compared:
1. Carbohydrate counting, where the participant determines the amount of carbohydrate in the meal and calculates the prandial insulin dose based on an individualised insulin: carbohydrate ratio
2. "Pankowska equation", where the carbohydrate content of the meal is used to determine the rapid insulin bolus dose, but the fat and protein content of the meal is also calculated as a "fat protein unit" which is then delivered as an extended insul
3 different insulin dosing algorithms will be compared: 1. Carbohydrate counting, where the participant determines the amount of carbohydrate in the meal and calculates the prandial insulin dose based on an individualised insulin: carbohydrate ratio 2. "Pankowska equation", where the carbohydrate content of the meal is used to determine the rapid insulin bolus dose, but the fat and protein content of the meal is also calculated as a "fat protein unit" which is then delivered as an extended insulin bolus 3. Food insulin index During a one week run-in period participants will be contacted daily by the research team. The pre and postprandial blood glucose levels will be reviewed and the participants pre-existing insulin: carbohydrate ratio will be adjusted by the participants treating clinician if required. The study is a crossover design with a single visit for each meal type for each insulin bolus. Subjects will be randomised to deliver either the high fat meal or the high protein meal for three consecutive days in week one. Subjects will then deliver the remaining meal for three consecutive days in week two Insulin dose will be calculated according to insulin: carbohydrate ratio for the carbohydrate counting arm. For the Pankowska Equation (PE), fat protein units will be calculated by PE and ICR. Food insulin index doses will be derived from published food insulin demand data and adjusted according to ICR. The clinician will determine the insulin doses. Insulin will be commenced 15 minutes prior to eating the test meal. Insulin will be delivered via insulin pump as a combination bolus with 60:40 split continued over 4 hours. The high fat test meal is chicken nuggets and chips containing 2085kj, 47g carbohydrate, 16g protein, 27g fat. The high protein test meal is spaghetti bolognaise containing 1983kj, 48g carbohydrate, 34g protein, 13g fat. Subjects will keep a food and activity diary throughout the study period.
Sponsors
John Hunter Children's Hospital
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
7 Years to 18 Years
Healthy volunteers
No
Inclusion criteria
Type 1 Diabetes >1 year Insulin pump therapy >6 months Age 7-18 years
Exclusion criteria
Coeliac disease Major medical conditions
Outcome results
None listed