Preliminary Evaluation of a New Semi-Closed-Loop Insulin Therapy System Over the Prandial Period in Adult Patients With Type 1 Diabetes: The WP6.0 Diabeloop Study. (November 2014)

• Record Type: Journal Article
• Authors: Quemerais, Marie Aude; Doron, Maeva; Dutrech, Florent; Melki, Vincent; Franc, Sylvia; Antonakios, Michel; Charpentier, Guillaume; Hanaire, Helene; Benhamou, Pierre Yves
• Other Names: Charpentier Guillaume non-byline-author.; Franc Sylvia non-byline-author.; Penfornis Alfred non-byline-author.; Reznik Yves non-byline-author.; Benhamou Pierre Yves non-byline-author.; Raccah Denis non-byline-author.; Renard Eric non-byline-author.; Guerci Bruno non-byline-author.; Jeandidier Nathalie non-byline-author.; Hanaire Helene non-byline-author.; Simon Chantal non-byline-author.; Doron Maeva non-byline-author.; Antonakios Michel non-byline-author.; Guillemaud Regis non-byline-author.
• Is Part Of: Journal of diabetes science and technology. Volume 8:Number 6(2014)
• Page Start: 1177
• Page End: 1184
• Publication Date: 2014-11
• Subjects: type 1 diabetes mellitus -- artificial pancreas -- closed-loop insulin therapy -- prandial bolus -- algorithm; Diabetes -- Periodicals; Medical technology -- Periodicals; Diabetes Mellitus -- Periodicals; 616.462005
• DOI: 10.1177/1932296814545668
• Languages: English
• ISSNs: 1932-2968

Abstract

There is room for improvement in the algorithms used in closed-loop insulin therapy during the prandial period. This pilot study evaluated the efficacy and safety of the Diabeloop algorithm (model predictive control type) during the postprandial period. This 2-center clinical trial compared interstitial glucose levels over two 5-hour periods (with/without the algorithm) following a calibrated lunch. On the control day, the amount of insulin delivered by the pump was determined according to the patient's usual parameters. On the test day, 50% or 75% of the theoretical bolus required was delivered, while the algorithm, informed of carbohydrate intake, proposed changes to insulin delivery every 15 minutes using modeling to forecast glucose levels. The primary endpoint was percentage of time spent at near normoglycemia (70-180 mg/dl). Twelve patients with type 1 diabetes (9 men, age 35.6 ± 12.7 years, HbA1c 7.3 ± 0.8%) were included. The percentage of time spent in the target range was 84.5 ± 20.8 (test day) versus 69.2 ± 33.9% (control day, P = .11). The percentage of time spent in hypoglycemia < 70 mg/dl was 0.2 ± 0.8 (test) versus 4.4 ± 8.2% (control, P = .18). Interstitial glucose at the end of the test (5 hours) was 127.5 ± 40.1 (test) versus 146 ± 53.5 mg/dl (control, P = .25). The insulin doses did not differ, and no differences were observed between the 50% and 75% boluses. In a semi-closed-loop configuration with manual priming boluses (25% or 50% reduction), the Diabeloop v1 algorithm was as successful as the manual method in determining the prandial bolus, without any exposure to excessive hypoglycemic risk.