Safety of Nighttime 2-Hour Suspension of Basal Insulin in Pump-Treated Type 1 Diabetes Even in the Absence of Low Glucose

Prebed and fasting blood glucose and β-hydroxybutyrate levels. A: Prebed glucose levels (in milligrams per deciliter) on suspend vs. nonsuspend nights were similar, with a wide range of prebed glucose levels. B: Likewise, prebed β-hydroxybutyrate levels were equivalent in the two study conditions. C: As expected, blood glucose levels in the fasting period tended to be higher after nights with basal insulin suspension (P < 0.0001). D: Fasting β-hydroxybutyrate levels tended to be higher in the fasting period after basal insulin suspension. Outliers are noted as closed circles. The dashed line at 0.9 mmol/L is the upper limit of blood β-hydroxybutyrate levels associated with trace urinary ketones.

Change in sensor glucose levels. Change in sensor glucose value (in milligrams per deciliter) is compared on suspend night (solid circles with solid line) vs. nonsuspend nights (open boxes with dashed line). Sensor glucose levels at the start of a suspend period (0 h), the end of the suspend period (2 h), and 4 h after the initiation of a suspend period (4 h) are noted. On nonsuspend nights, sensor glucose levels were assessed at time periods that would coincide with suspend nights (i.e., 11:30 p.m.–1:30 a.m. or 2:00–4:00 a.m.).