Preventing Post-Exercise Nocturnal Hypoglycemia in Children with Type 1 Diabetes

Objective To determine the effects of reducing overnight basal insulin or a bedtime dose of terbutaline on nocturnal blood glucose (BG) nadir and hypoglycemia after exercise in children with type 1 diabetes mellitus. Study design Sixteen youth (mean age 13.3 years) on insulin pumps were studied overnight on 3 occasions after a 60-minute exercise session with BG measurements every 30 minutes. Admissions were randomized to bedtime treatment with oral terbutaline 2.5 mg, 20% basal rate insulin reduction for 6 hours, or no treatment. Results Mean overnight nadir BG was 188 mg/dL after terbutaline and 172 mg/dL with basal rate reduction compared with 127 mg/dL on the control night (P = .002 and .042, respectively). Terbutaline eliminated nocturnal hypoglycemia but resulted in significantly more hyperglycemia (>= 250 mg/dL) when compared with the control visit (P < .0001). The basal rate reduction resulted in fewer BG readings < 80 and < 70 mg/dL but more readings >= 250 mg/dL when compared with the control visit. Conclusions A basal insulin rate reduction was safe and effective in raising post-exercise nocturnal BG nadir and in reducing hypoglycemia in children with type 1 diabetes mellitus. Although effective at preventing hypoglycemia, a 2.5-mg dose of terbutaline was associated with hyperglycemia. (J Pediatr 2010; 157:784-8).