Basal insulin and total daily insulin dose in children with type 1 diabetes using insulin pumps.

Objective: To assess the contribution of basal insulin to the total daily dose (CBITDD) and to identify the determinant factors in children with type 1 diabetes mellitus.

Study Design: Cross-sectional study in which the basal insulin requirement was established based on a memory read-out of insulin delivery from pumps. Factors such as glycated haemoglobin A1c (HbA1c), fasting C-peptide, standard deviation score of body mass index (sdsBMI) and demographic data were determined during routine hospital visits. Study group included a total of 90 well-controlled diabetic children with the mean HbA1c 6.6 +/- 0.7 (5.2-7.9), age 10.4 +/- 4.4 yr (1.1-17.9 yr), diabetes duration 3.0 +/- 2.6 yr (0.3-10.9 yr) and sdsBMI 0.08 (-2.27 to 1.79), excluding patients with ketoacidosis or infectious diseases.

Results: Correlations between CBITDD and age (r = 0.39 and p < 0.005) and diabetes duration (r = 0.61 and p < 0.0001) and an inverse correlation with C-peptide (r = -0.41 and p = 0.0001) were found. C-peptide-positive patients had a significantly lower percentage of basal insulin compared with C-peptide-negative patients (20.6 +/- 11 vs. 31.6 +/- 11.0%, respectively; p = 0.0004); yet, no significant difference in total insulin daily dose (0.65 +/- 0.3 vs. 0.78 +/- 0.2 U/kg/d, respectively) was observed.

Conclusions: The percentage of basal insulin in diabetic children is below 50% and in well-controlled diabetic children is related to the fasting C-peptide level, age of patient and diabetes duration but not to HbA1c and sdsBMI.