Pure-protein load for children with type 1 diabetes: is any additional insulin needed? A randomized controlled study

Study in adults with T1D showed that delivery of insulin for pure-protein meals may not be obligatory. The aim of this study was to assess the effects of whey isolate protein drink consisting of 50 g/200 kcal from pure protein on postprandial glycemia (PPG) following with square-wave insulin bolus in comparison with no insulin strategy in T1D children on insulin pumps.

This was a randomized, double-blind, cross-over study including 58 children with mean: age 14.62 ± 3.64 years. Participants were randomly assigned into two treatment orders: NB-SQ (no bolus on the first day) and SQ-NB (square-bolus on the first day). The primary outcome was PPG during a 5-h follow-up. The secondary outcome was the frequency of hypoglycemia and glycemic variability parameters.

PPG [mg/dl] since 150 min of the follow-up was significantly lower when square-wave bolus was delivered (group SQ vs NB); at 150, 180, 210, 240, 270, 300 min: 130.6 versus 154.5 (p = 0.009), 153.4 versus 124.9 (p = 0.004), 151.0 versus 118.7 (p = 0.003), 146.4 versus 114.2 (p = 0.002), 141.2 versus 107.7 (p = 0.001), 131.0 versus 105.1 (p = 0.005). We observed statistically significant difference in overall rate of hypoglycemia < 70 mg/dl between groups SQ versus NB: 6.8% versus 2.5% (p = 0.001). The overall rate of hypoglycemia below 54 mg/dl was < 1% (p = 0.452).

A meal containing 50 g of pure protein may be consumed without additional insulin dose. An additional square-wave bolus may be beneficial in reducing PPG. To avoid hypoglycemia, lower insulin dose should be calculated for 100 kcal from protein than for individual insulin-to-carb ratio.