Using closed-loop system maintained better overnight glucose control.
A study was performed in multiple countries to assess at-home use of a single hormone artificial pancreas. The investigation was a crossover, randomized study conducted in France, Italy, and the Netherlands. Researchers assessed the use of the artificial pancreas during evening and overnight periods, and found that overnight hypoglycemia was significantly reduced.
Researcher Jort Kropff, MD, of the Academic Medical Center at the University of Amsterdam, and colleagues examined data from 32 adults with T1DM using insulin pump therapy (average age of 47 years; 18 men; average BMI of 25.1 kg/m2; average HbA1c of 8.2%; average duration of diabetes 29 years). Researchers collected data between April and December of 2014. There were three patients using continuous glucose monitoring (CGM) prior to the study. Exclusion criteria were patients with severe hypoglycemia or ketoacidosis in the past year.
In these two, 8-week study periods, participants were assigned an artificial pancreas system (Dexcom G4 Platinum CGM and Accu-Chek Spirit Combo insulin pump connected to a modified smartphone with a model predictive control algorithm) that was used from dinner until wake time. In addition, a sensor-augmented pump therapy during the day was utilized, or sensor-augmented pump therapy alone. The subjects were assigned to these two categories randomly, and all subjects used both therapies without restriction on their daily activities.
Investigators found that subjects using the artificial pancreas spent more time in the target range compared to those who used sensor-augmented pump therapy alone (66.7% vs 58.1%; paired difference, 8.6%). This was concluded through reductions of mean time spent in both hyperglycemia and hypoglycemia. Furthermore, subjects using the artificial pancreas displayed greater reduction in HbA1c compared to those using sensor-augmented pump alone (-0.3% vs. -0.2%; paired difference -0.2%). No serious adverse events were found during the study, where mild to moderate events were considered insignificant.
Authors claim this study is the first in which glucose control was investigated over a prolonged period and not just overnight. In addition, the study included a difficult post-dinner period. Researchers believe this study provides evidence that artificial pancreas use is safe and effective for the in-home setting. Nonetheless, future studies need to incorporate longer-term analysis as well as identify improvements in HbA1c over 3 months or more.
- Incidents of overnight hypoglycemia is significantly reduced for adults using the closed-loop control system artificial pancreas compared to sensor-augmented pump.
- T1DM patients using the artificial pancreas closed-loop system spend more time in the target range during the evening.
- There was no significant difference in the mean glucose concentration during the evening between the closed-loop and sensor-augmented pump.
- Future studies need to be performed to analyze longer-term outcomes.
Kropff, Jort, et al. “2 month evening and night closed-loop glucose control in patients with type 1 diabetes under free-living conditions: a randomized crossover trial.” The Lancet Diabetes & Endocrinology (2015). JAMA. 2015; 313: 45–53