Feasibility of a portable bihormonal closed-loop system to control glucose excursions at home under free-living conditions for 48 hours.
BACKGROUND
This study assessed the feasibility of a portable bihormonal closed-loop system at home.


METHODS
Sixteen pump-treated patients with type 1 diabetes received 48 h of closed-loop therapy with a telemonitored insulin- and glucagon-delivering closed-loop system and 48 h of patient-managed open-loop therapy.


RESULTS
Owing to technical problems in five cases, only 11 patients could be analyzed. Whereas median (interquartile range) glucose levels were not significantly different during Day 1 of open-loop control (OL1) from closed-loop control (CL1) (8.27 [0.83] mmol/L vs. 8.84 [1.47] mmol/L; P=0.206), they were significantly lower during Day 2 of closed-loop control (CL2) versus open-loop control (OL2) (7.70 [2.29] mmol/L vs. 8.84 [0.87] mmol/L; P=0.027). Time spent in euglycemia (3.9-10 mmol/L) was comparable with 67.2% (38.5%) in OL1 versus 79.2% (16.9%) in CL1 (P=0.189) and 66.0% (29.8%) in OL2 versus 76.5% (23.9%) in CL2 (P=0.162). Time spent in hypoglycemia (<3.9 mmol/L) was comparable on Day 1 of control (OL1, 0.68% [8.68%]; CL1, 2.08% [7.61%]; P=0.593) but significantly higher during Day 2 of control (OL2, 0.00% [11.07%]; CL2, 2.8% [9.8%]; P=0.0172) (P=0.017).


CONCLUSIONS
Bihormonal closed-loop control is feasible at home, with comparable time in euglycemia to open-loop control and significantly lower median glucose levels on Day 2 of control at the expense of more time in hypoglycemia, albeit still at a very low percentage of time.
1 Department of Internal Medicine, Academic Medical Centre , Amsterdam, The Netherlands .
Arianne C
AC
van Bon
Yoeri M
YM
Luijf
Rob
R
Koebrugge
Robin
R
Koops
Joost B L
JB
Hoekstra
J Hans
JH
DeVries
D059250:Administration, Metronomic; D000328:Adult; D000465:Algorithms; D001786:Blood Glucose / Q000378:metabolism*; D015190:Blood Glucose Self-Monitoring; D002138:Calibration; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy*; D005240:Feasibility Studies; D005260:Female; D005934:Glucagon / Q000097:blood; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D007328:Insulin / Q000008:administration & dosage*; D007332:Insulin Infusion Systems; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory; D017216:Telemedicine
D001786:Blood Glucose; D005934:Glucagon; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; C517652:hemoglobin A1c protein, human