Day and night closed-loop control in adults with type 1 diabetes: A comparison of two closed-loop algorithms driving continuous subcutaneous insulin infusion versus patient self-management

Abstract

Objective-To compare two validated closed-loop (CL) algorithms versus patient selfcontrol with CSII in terms of glycemic control. Research design and methods-This study was a multicenter, randomized, three-way crossover, open-label trial in 48 patients with type 1 diabetesmellitus for at least 6months, treatedwith continuous subcutaneous insulin infusion. Blood glucosewas controlled for 23 h by the algorithmof the Universities of Pavia and Padova with a Safety Supervision Module developed at the Universities of Virginia and California at Santa Barbara (international artificial pancreas [iAP]), by the algorithm of University of Cambridge (CAM), or by patients themselves in open loop (OL) during three hospital admissions including meals and exercise. The main analysis was on an intention-totreat basis. Main outcome measures included time spent in target (glucose levels between 3.9 and 8.0 mmol/L or between 3.9 and 10.0 mmol/L after meals). Results-Time spent in the target range was similar in CL and OL: 62.6% for OL, 59.2% for iAP, and 58.3% for CAM. While mean glucose level was significantly lower in OL (7.19, 8.15, and 8.26 mmol/L, respectively) (overall P = 0.001), percentage of time spent in hypoglycemia (<3.9mmol/L) was almost threefold reduced during CL (6.4%, 2.1%, and 2.0%) (overall P = 0.001) with less time ≤2.8 mmol/L (overall P = 0.038). There were no significant differences in outcomes between algorithms. Conclusions-Both CAM and iAP algorithms provide safe glycemic control. © 2013 by the American Diabetes Association.