Clinical evaluation of an automated artificial pancreas using zone-model predictive control and health monitoring system

Diabetes Technol Ther. 2014 Jun;16(6):348-57. doi: 10.1089/dia.2013.0231. Epub 2014 Jan 28.

Abstract

Background: This study was performed to evaluate the safety and efficacy of a fully automated artificial pancreas using zone-model predictive control (zone-MPC) with the health monitoring system (HMS) during unannounced meals and overnight and exercise periods.

Subjects and methods: A fully automated closed-loop artificial pancreas was evaluated in 12 subjects (eight women, four men) with type 1 diabetes (mean±SD age, 49.4±10.4 years; diabetes duration, 32.7±16.0 years; glycosylated hemoglobin, 7.3±1.2%). The zone-MPC controller used an a priori model that was initialized using the subject's total daily insulin. The controller was designed to keep glucose levels between 80 and 140 mg/dL. A hypoglycemia prediction algorithm, a module of the HMS, was used in conjunction with the zone controller to alert the user to consume carbohydrates if the glucose level was predicted to fall below 70 mg/dL in the next 15 min.

Results: The average time spent in the 70-180 mg/dL range, measured by the YSI glucose and lactate analyzer (Yellow Springs Instruments, Yellow Springs, OH), was 80% for the entire session, 92% overnight from 12 a.m. to 7 a.m., and 69% and 61% for the 5-h period after dinner and breakfast, respectively. The time spent < 60 mg/dL for the entire session by YSI was 0%, with no safety events. The HMS sent appropriate warnings to prevent hypoglycemia via short and multimedia message services, at an average of 3.8 treatments per subject.

Conclusions: The combination of the zone-MPC controller and the HMS hypoglycemia prevention algorithm was able to safely regulate glucose in a tight range with no adverse events despite the challenges of unannounced meals and moderate exercise.

Trial registration: ClinicalTrials.gov NCT01472406.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Algorithms
  • Blood Glucose / metabolism*
  • Blood Glucose Self-Monitoring
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Diabetes Mellitus, Type 1 / physiopathology
  • Female
  • Humans
  • Hypoglycemia / prevention & control*
  • Hypoglycemic Agents / administration & dosage*
  • Hypoglycemic Agents / adverse effects
  • Insulin / administration & dosage*
  • Insulin / adverse effects
  • Insulin Infusion Systems
  • Male
  • Meals
  • Middle Aged
  • Monitoring, Physiologic*
  • Pancreas, Artificial*
  • Predictive Value of Tests

Substances

  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin

Associated data

  • ClinicalTrials.gov/NCT01472406