Objective: The purpose of this study was to determine whether, in a group of children with type 1 diabetes using insulin pump, a prebedtime snack with a relatively high fat content provides greater protection from nocturnal hypoglycemia than a snack containing the same amount of carbohydrate and protein but a lower fat content.
Research design and methods: Ten subjects, aged 6 to <18 yr, in a trial evaluating the Abbott Navigator glucose sensor, agreed to this ancillary study. On 12 or more separate nights, each subject was randomized by a Web site to a carbohydrate-low-fat (30 g CHO, 2.5 g protein, and 1.3 g fat; 138 kcal) snack or a carbohydrate-high-fat (30 g CHO, 2 g protein, and 20 g fat; 320 kcal) snack. Subjects used their usual evening snack algorithm to determine the size (in 15-g carbohydrate increments) and insulin dosage.
Results: Average glucose on 128 valid study nights before snack was similar in both groups. The proportion of nights with hypoglycemia (a sensor or meter glucose value <or=70 mg/dL) was similar in both groups (19% high fat vs. 20% low fat), as was the proportion of nights with hyperglycemia (a glucose >or=200 mg/dL and at least 50 mg/dL above baseline, 35% high fat vs. 30% low fat).
Conclusions: There were no statistical differences between the high- and low-fat snacks on the frequency of hyperglycemia or hypoglycemia. This study highlights the feasibility of web-based research in patients' home environment.