Insulin Requirement for Pure-protein Meal in Children With Type 1 Diabetes on Insulin Pumps.

Insulin Requirement for Pure- Protein Meal in Children With Type 1 Diabetes Treated With Continuous Subcutaneous Insulin Infusion - a Cross-over, Randomized Trial.

This is a randomized, cross-over study. The aim of this study is to compare the post-prandial glycaemic variability after pure protein meal following with an administration of square-wave bolus of meal-insulin or without any meal-insulin bolus on the other day. Prolonged post-prandial glycaemic variability will be identified using the self-monitoring of blood glucose (10-point curve) and CGMS.

The square-wave bolus (for meals rich in fat and/or protein) is evenly delivered over several hours as programmed by the patient. The required insulin dose will be calculated based on patient's insulin-exchange ratio. Pure protein meal will be given 3 hours after a first breakfast. To provide the minimal impact of the previous breakfast, all patients will receive up to 120 kcal of carbohydrates and <100 kcal from protein and fat for the first breakfast (without any extended bolus) Patients receive a standardized pure protein meal at a second breakfast time. Meal insulin will be given as a square bolus or no meal -insulin will be given at all. The 5h post-meal glucose excursions will be recorded by self-blood glucose measurements (SMBG) (every 30 minutes) and continuous glucose monitoring system (CGMS). The intervention is taking part under in-patient clinical conditions.

diabetes type 1, insulin pump, prandial insulin requirement, pure protein meal, high protein meal, square bolus, square-wave bolus, insulin bolus, dietary protein

On the first study day, insulin bolus was not given before a standardized pure protein meal. On the second day, pre-breakfast insulin was given as a square-wave bolus before the same standardized pure protein meal. The fat-protein-insulin ratio on both study days were identical to the patient's ratio when entering trial. Kind of study bolus insulin will be a rapid-acting insulin analog same as previously used by the participant (before entering the trial) - insulin aspart, insulin lispro or insulin glulisine

On the first study day, pre-breakfast insulin was given as a square-wave bolus before a standardized pure protein meal. On the second day, insulin bolus was not given before the same standardized pure protein meal. The fat-protein-insulin ratio on both study days were identical to the patient's ratio when entering trial. Kind of study bolus insulin will be a rapid-acting insulin analog same as previously used by the participant (before entering the trial) - insulin aspart, insulin lispro or insulin glulisine

A kind of study bolus insulin will be insulin aspart if participant used insulin aspart before entering the trial

A kind of study bolus insulin will be insulin lispro if participant used insulin lispro before entering the trial

A kind of study bolus insulin will be insulin lispro if participant used insulin lispro before entering the trial

Inclusion Criteria: duration of type 1 diabetes longer than 12 months insulin pump therapy longer than 3 months written informed consent by patients and parents insulin requirement more than 0,5 units/kg/day Exclusion Criteria: diabetes related complications (e.g. nephropathy) chronic kidney diseases any disease judged by the investigator to affect the trial withdrawal of consent to participate in the study