Bedtime snacking deteriorates continuous glucose monitoring metrics in young children with type 1 diabetes: a randomized controlled crossover trial

Abstract Objective To determine if a bedtime snack in young children with type 1 diabetes (T1D) prevents nocturnal hypoglycemia, and the impact on glycemia overnight. Methods In this randomized controlled crossover trial, 10 grams of carbohydrate (milk, yogurt, and kefir) was given 150–180 minutes after dinner over three nights to 5-8-year-old children with T1D using multiple daily injection therapy. Continuous glucose monitoring (CGM) data were collected for 6 hours following the snacks on one control and three snack nights. Time in 70–180 mg/dl range (TIR), time below 70 mg/dL (TBR), and other metrics were analyzed according to international CGM consensus. Trial day was terminated if blood glucose exceeded 300 mg/dL or fell below 70 mg/dL. Results Of 28 children (13 female, mean age 6.6 ± 0.8 years, HbA1c 7.0 ± 0.5%), mean glucose values before the test snacks were 137.8 ± 14.5 mg/dL for milk, 141.9 ± 16.9 mg/dL for yogurt, 136 ± 19.1 mg/dL for kefir, and 140.8 ± 17.0 mg/dL for control without significant difference (p = 0.548). TIR was 34.7% for milk, 38.7%. for yogurt, 45.9% for kefir, and 75.5% for control during the 6-hour post snack period, with TIR on the control day significantly higher than the three snack days (p  0.05). Of 112 trial days, 13 days were terminated due to hyperglycemia (> 300 mg/dL) (8 milk, 4 yogurt, 1 kefir), and 3 trial days due to hypoglycemia (< 70 mg/dL) (1 yogurt, 2 control). Conclusion Bedtime snacking in young children with T1D impairs nocturnal glycemia and reduces TIR, without decreasing the frequency of hypoglycemia.