To determine the insulin requirement for a high fat, high protein breakfast to optimise postprandial glycaemic excursions in children and young people with type 1 diabetes using insulin pumps.
Twenty-seven participants age 10-23 years, BMI <95th percentile (2-18 years) or BMI <30 kg/m2 (19-25 years) and HbA1c ≤64 mmol/mol (≤8.0%) consumed a high fat, high protein breakfast (carbohydrate:30g, fat:40g, protein:50g) on four days. In this cross-over trial insulin was administered, based on the insulin-to-carbohydrate ratio (ICR) of 100% (control), 120%, 140% and 160%, in an order defined by a randomisation sequence and delivered in a combination bolus, 60% ¼ hr pre-meal and 40% over 3 hr. Postprandial sensor glucose was assessed for 6 hr.
Compared to 100%ICR, 140%ICR and 160%ICR resulted in significantly lower 6 hr areas under the glucose curves: mean (95%CI) (822 mmol/L.min [605,1039] and 567 [350,784] vs 1249 [1042,1457],p≤0.001) and peak glucose excursions (4.0 mmol/L [3.0,4.9] and 2.7 [1.7,3.6] vs 6.0 [5.0,6.9],p<0.001). Rates of hypoglycaemia for 100%-160%ICR were 7.7%, 7.7%, 12% and 19% respectively (p≥0.139). With increasing insulin dose, a step-wise reduction in mean glucose excursion was observed from 1-6 hr (p=0.008).
Incrementally increasing the insulin dose for a high fat, high protein breakfast resulted in a predictable, dose-dependent reduction in postprandial glycaemia: 140%ICR improved postprandial glycaemic excursions without a statistically significant increase in hypoglycaemia. These findings support a safe, practical method for insulin adjustment for high fat, high protein meals that can be readily implemented in practice to improve postprandial glycaemia.