The optimal type of bolus following a 'Mediterranean' meal in children and adolescents with type 1 diabetes using insulin pump therapy

Background and aims: Few is known about the best type of bolus before meals in patients with type 1 diabetes (T1DM) using insulin pump therapy. Last year we observed that the best bolus for a 'pizza' meal (pizza 'margherita') is 30/70 dual wave bolus extended over 6 hours. After this, we start to con-sider that for a 'Mediterranean' meal (more carbohydrate and less proteins and lipids) a dual wave bolus might be better than a simple bolus. The aim of our study is to compare a simple bolus with different kind of dual wave bolus in order to identify the optimal one in case of a Mediterranean meal. Materials and methods: We evaluated 26 children and adolescents, aged 5-23 yrs (mean 15.40±4.84 yrs) with T1DM from 1 to 19 yrs (9.67±4.91 yrs), BMI 22.01±4.41 kg/m2, in therapy with subcutaneous insulin infusion (insu-lin requirement 0.76±0.14U/kg/day). Each patient participated in a study to compare postprandial glucose values following 6 meal bolus regimens for a daily meal (1600-2000 kcal according to children age). Each patient utilized the following 6 aspart regimens on three consecutive days, and glucose values were recorded with SMBG: a) a single-wave bolus (100% of insulin given im-mediately) injected 15 min before the meal; b) a single-wave bolus (100% of insulin given immediately) injected just before the meal; c) 4-h dual-wave bolus (50% of insulin given immediately and 50% given over a 4-h period) injected 15 min prior the meal; d) 4-h dual-wave bolus (50% of insulin give immediately and 50% given over a 4-h period) injected just before the meal; e) 4-h dual wave bolus (70% given immediately and 30% given over a 4-h period) injected 15 min before the meal; and f) 4-h dual wave bolus (70% given immediately and 30% given over a 4-h period) injected just before the meal. Total CHO was kept constant for each meal; insulin dose was calculated according to glycaemic value and CHO, using ISF and INS:CHO ratio. per-sonalized for each patient. Results: The results are shown in the table. Conclusion: 70/30 double wave bolus extended over 4-h period following a Mediterranean meal injected 15 min before provided significantly less post-prandial hyperglycemia during the 4-h period. Single-wave bolus could be used only if given 15 min before meal, even if we observed a rise in glycaemic values in the last two hours of the study.