Efficacy of dual-hormone artificial pancreas to alleviate the carbohydrate-counting burden of type 1 diabetes: A randomized crossover trial

AimCarbohydrate-counting is a complex task for many patients with type 1 diabetes. This study examined whether an artificial pancreas, delivering insulin and glucagon based on glucose sensor readings, could alleviate the burden of carbohydrate-counting without degrading glucose control.MethodsTwelve adults were recruited into a randomized, three-way, crossover trial (ClinicalTrials.gov identifier No. NCT01930097). Participants were admitted on three occasions from 7AM to 9PM and consumed a low-carbohydrate breakfast (women: 30 g; men: 50 g), a medium-carbohydrate dinner (women: 50 g; men: 70 g) and a high-carbohydrate lunch (women: 90 g; men: 120 g). At each visit, glucose levels were randomly regulated by: (1) conventional pump therapy; (2) an artificial pancreas (AP) accompanied by prandial boluses, matching the meal's carbohydrate content based on insulin-to-carbohydrate ratios (AP with carbohydrate-counting); or (3) an AP accompanied by prandial boluses based on qualitative categorization (regular or large) of meal size (AP without carbohydrate-counting).ResultsThe AP without carbohydrate-counting achieved similar incremental AUC values compared with carbohydrate-counting after the low- (P = 0.54) and medium- (P = 0.38) carbohydrate meals, but yielded higher post-meal excursions after the high-carbohydrate meal (P = 0.004). The AP with and without carbohydrate-counting yielded similar mean glucose levels (8.2 ± 2.1 mmol/L vs. 8.4 ± 1.7 mmol/L; P = 0.52), and both strategies resulted in lower mean glucose compared with conventional pump therapy (9.6 ± 2.0 mmol/L; P = 0.02 and P = 0.03, respectively).ConclusionThe AP with qualitative categorization of meal size could alleviate the burden of carbohydrate-counting without compromising glucose control, although more categories of meal sizes are probably needed to effectively control higher-carbohydrate meals.