Comparison between preprandial vs. postprandial insulin aspart in patients with type 1 diabetes on insulin pump and real-time continuous glucose monitoring.

Background: The objective was to compare glycemic control between preprandial and postprandial bolus administration (15 min before [PRE] or immediately after the meal [POST]) in patients with type 1 diabetes using insulin pump and real-time continuous glucose monitoring.

Methods: Between September 2015 and February 2016, a single-centre, open randomized, 2-way crossover study of patients on bolus insulin aspart administration was conducted during two 14-day periods and according to 2 administration regimen schedules (PRE/POST or POST/PRE). Inclusion criteria were as follows: patients with type 1 diabetes, ≥18 and ≤ 65 years old, treated with insulin aspart using a Medtronic® insulin pump and trained on functional insulin therapy. Patients were randomly assigned to either regimen schedule. At the beginning of each period, each patient was provided with a standardized high fat meal. Primary outcome was the area under the curve for interstitial glucose above 140 mg/dL per minute (AUC > 140 mg/dL/min) during each period. Secondary outcomes were time spent in hypo/eu/hyperglycemia, glycemic variability indices, and AUC during 4 hours after high fat meal calculated with continuous glucose monitoring data.

Results: Twenty-two patients were included. Mean AUC > 140 mg/dL/min was statistically higher in patients on POST (43.70 mg/dL/min; 95%CI: 34.08 to 53.31) versus PRE insulin aspart regimen (37.24 mg/dL/min 95%CI: 27.63 to 46.85) (P = 0.03). Mean interstitial glycemia and glycemic variability indices were also increased (P < 0.05) on POST regimen. The mean AUC 4 hours after the high fat meal was higher on POST regimen but not statistically different (P = 0.06).

Conclusions: In our study, postprandial administration of insulin aspart appears to mildly increase glycemic excursion and glycemic variability.