Predictive Low-Glucose Insulin Suspension Reduces Duration of Nocturnal Hypoglycemia in Children Without Increasing Ketosis

Abstract

Objective: Nocturnal hypoglycemia can cause seizures and is a major impediment to tight glycemic control, especially in young children with type 1 diabetes. We conducted an in-home randomized trial to assess the efficacy and safety of a continuous glucose monitor-based overnight predictive low-glucose suspend (PLGS) system.

Research design and methods: In two age-groups of children with type 1 diabetes (11-14 and 4-10 years of age), a 42-night trial for each child was conducted wherein each night was assigned randomly to either having the PLGS system active (intervention night) or inactive (control night). The primary outcome was percent time <70 mg/dL overnight.

Results: Median time at <70 mg/dL was reduced by 54% from 10.1% on control nights to 4.6% on intervention nights (P < 0.001) in 11-14-year-olds (n = 45) and by 50% from 6.2% to 3.1% (P < 0.001) in 4-10-year-olds (n = 36). Mean overnight glucose was lower on control versus intervention nights in both age-groups (144 ± 18 vs. 152 ± 19 mg/dL [P < 0.001] and 153 ± 14 vs. 160 ± 16 mg/dL [P = 0.004], respectively). Mean morning blood glucose was 159 ± 29 vs. 176 ± 28 mg/dL (P < 0.001) in the 11-14-year-olds and 154 ± 25 vs. 158 ± 22 mg/dL (P = 0.11) in the 4-10-year-olds, respectively. No differences were found between intervention and control in either age-group in morning blood ketosis.

Conclusions: In 4-14-year-olds, use of a nocturnal PLGS system can substantially reduce overnight hypoglycemia without an increase in morning ketosis, although overnight mean glucose is slightly higher.

Trial registration: ClinicalTrials.gov NCT01823341.

Figure 1

Percentage of nights with various durations of glucose levels <60 mg/dL for the two treatments groups. A: Among participants 11–14 years of age, the percentages of nights when total cumulative time with sensor glucose <60 mg/dL was >30, 60, 120, and 180 min are shown for the intervention and control arms along with the relative percent reduction. B: The same data as A for participants 4–10 years of age.

Figure 2

Median glucose and percent time when glucose was <70 mg/dL from system activation for the two treatment groups. A: Among participants 11–14 years of age, median sensor glucose (mg/dL) and percent time <70 mg/dL every 10 min by minutes from system activation are shown for the intervention and control arms. B: The same data as A for participants 4–10 years of age.

Figure 3

Median percent time when glucose was <70 mg/dL and >180 mg/dL after system deactivation for the two treatment groups. A: Among participants 11–14 years of age, hourly median percentage of time sensor glucose was <70 mg/dL and >180 mg/dL, starting 2 h before and ending 12 h after system deactivation, are shown for the intervention and control arms. B: The same data as A for participants 4–10 years of age.