Feasibility study of automated overnight closed-loop glucose control under MD-logic artificial pancreas in patients with type 1 diabetes: the DREAM Project

Diabetes Technol Ther. 2012 Aug;14(8):728-35. doi: 10.1089/dia.2012.0004.


Background: Artificial pancreas systems may offer a potential major impact on the normalization of metabolic control and preventing hypoglycemic events. This study aims to establish near-normal overnight glucose control and reduce the risk of nocturnal hypoglycemia using the MD-Logic Artificial Pancreas (MDLAP), an algorithm that was developed by our research group. This inpatient feasibility study is the first step towards implementing an overnight closed-loop MDLAP system at the patient's home.

Subjects and methods: Seven patients with type 1 diabetes (three adolescents and four adults; mean±SD age, 20.6±4.7 years; duration of diabetes, 9.6±2.6 years; body mass index, 24.3±3.9 kg/m(2); and glycated hemoglobin, 7.8±0.8%) participated in a total of 14 closed-loop overnight sessions. Each participant underwent two closed-loop inpatient sessions starting at dinner alone and at dinner following exercise. The closed-loop inpatient sessions were compared with data derived from nights spent at home with an open-loop system in a similar scenario to the study protocol.

Results: The mean percentage of time spent in the near normal glucose range of 63-140 mg/dL was 83±16%, and the median (interquartile range) was 85% (78-92%) for the overnight closed-loop sessions compared with 34±31% and 27% (6-57%) in the homecare open-loop setting, respectively. During the overnight closed-loop sessions at dinner alone 92±9% of the sensor values ranged within target range, compared with 73±19% for the sessions following exercise (P=0.03). No hypoglycemic (<63 mg/dL) events occurred during the closed-loop sessions.

Conclusion: Closed-loop insulin delivery under MDLAP is a feasible and safe solution to control overnight glycemia.

Trial registration: ClinicalTrials.gov NCT00541515.

MeSH terms

  • Algorithms*
  • Blood Glucose / metabolism*
  • Blood Glucose Self-Monitoring
  • Circadian Rhythm
  • Diabetes Mellitus, Type 1 / blood*
  • Diabetes Mellitus, Type 1 / drug therapy
  • Equipment Design
  • Feasibility Studies
  • Female
  • Glycated Hemoglobin A / metabolism*
  • Humans
  • Hypoglycemic Agents / administration & dosage*
  • Insulin / administration & dosage*
  • Insulin Infusion Systems
  • Male
  • Monitoring, Physiologic
  • Pancreas, Artificial*
  • Young Adult


  • Blood Glucose
  • Glycated Hemoglobin A
  • Hypoglycemic Agents
  • Insulin
  • hemoglobin A1c protein, human

Associated data

  • ClinicalTrials.gov/NCT00541515