Preventing post-exercise nocturnal hypoglycemia in children with type 1 diabetes

Abstract

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.

Trial registration: ClinicalTrials.gov NCT00974051.

Copyright © 2010 Mosby, Inc. All rights reserved.

Figures

Figure 1

Overnight mean blood glucose level curves for the three study visits p

Figure 2

Nocturnal BG nadir by bedtime BG *p = 0.003 terbutaline vs control **p = 0.016 basal rate reduction vs. control

Figure 3

Drop in BGL from bedtime to nocturnal nadir by visit type *pair-wise tests vs control

Figure 4

Effect of Hypoglycemia During Exercise on Nocturnal BG Nadir, by treatment group * p = 0.02 ** p = 0.02