Application of novel dual wave meal bolus and its impact on glycated hemoglobin A1c level in children with type 1 diabetes.

Background: An insulin pump is an advanced technology offering new options of bolus - normal (N), dual wave (D-W) or square wave (S-W) bolus to deliver mealtime insulin.

Objectives: To assess the impact of D-W/S-W boluses on metabolic control (glycated haemoglobin A1c, HbA1c) and to estimate the paediatric patients compliance with implementation of this system in daily practice.

Methods: The cross-sectional study included 499 records of patients aged 0-18 yr. Data from the insulin pump memory provided information on the number of D-W/S-W boluses during a 2-wk period, the insulin requirement (U/kg/d) and the percentage of basal insulin. The HbA1c value (%) and the patient's weight were determined during medical examinations. Mealtime dose of insulin in D-W/S-W bolus was calculated based on the amount of carbohydrate and fat/protein products.

Results: The number of applied D-W/S-W boluses was 16.6 +/- 0.77/14 d (ranged 0-95), while 18.8% of patients did not program D-W/S-W boluses. The lowest HbA1c value was found in the group using two and/or more D-W/S-W boluses per day (p = 0.001) compared with the group administrating less than one D-W/S-W bolus/d. Patients with HbA1c level <7.5% had a statistically higher relevant number of D-W/S-W boluses, 19.55 (95% CI: 17.44-21.65) vs. 12.42 (95% CI: 10.22-14.61) (p < 0.001), while there was no correlation between the number of boluses and HbA1c in patients in the remission phase (<0.5 IU/kg/d) (r = 0.012, p = 0.930).

Conclusions: Patients using at least one D-W/S-W bolus per day achieved a recommended level of HbA1c. Paediatric patients with type 1 diabetes mellitus were found to be able to apply D-W/S-W boluses in daily self-treatment process based on food counting.