Novel Use of Glucagon in a Closed-Loop System for Prevention of Hypoglycemia in Type 1 Diabetes

  1. W. Kenneth Ward, M.D.(1)
  1. (1) Oregon Health & Science University, Portland, OR 97239
  2. (2) Legacy Health, Portland, OR 97232

Abstract

Objective – To minimize hypoglycemia in subjects with type 1 diabetes by automated glucagon delivery in a closed-loop insulin delivery system.

Research design and methods – Adult subjects with type 1 diabetes underwent one closed-loop study with insulin plus placebo and one study with insulin plus glucagon given at times of impending hypoglycemia. Seven subjects received glucagon using high gain parameters and six subjects received glucagon in a more prolonged manner using low gain parameters. Blood glucose levels were measured every ten minutes and insulin and glucagon infusions were adjusted every five minutes. All subjects received a portion of their usual pre-meal insulin after meal announcement.

Results – Automated glucagon plus insulin delivery, as compared to placebo plus insulin, significantly reduced time spent in the hypoglycemic range (15 ± 6 vs. 40 ± 10 min per day, p = 0.04). Compared to placebo, high gain glucagon delivery reduced the frequency of hypoglycemic events (1.0 ± 0.6 vs. 2.1 ± 0.6 events per day, p = 0.01) and the need for carbohydrate treatment (1.4 ± 0.8 vs. 4.0 ± 1.4 treatments per day, p = 0.01). Glucagon given with low gain parameters did not significantly reduce hypoglycemic event frequency (NS), but did reduce frequency of carbohydrate treatment (p = 0.05).

Conclusions – During closed-loop treatment in subjects with type 1 diabetes, high gain pulses of glucagon decreased the frequency of hypoglycemia. Larger and longer term studies will be required to assess the effect of ongoing glucagon treatment on overall glycemic control.

Footnotes

    • Received December 10, 2009.
    • Accepted March 8, 2010.

This Article

  1. Diabetes Care
  1. All Versions of this Article:
    1. dc09-2254v1
    2. 33/6/1282 most recent