Closed-loop insulin therapy improves glycemic control in young diabetics
Closed-loop insulin therapy improves glycemic control in children under age seven who have type 1 diabetes.
“Children with high HbA1c or frequent episodes of hypoglycemia, despite all attempts at optimizing open-loop control, are most likely to benefit from the approach,” Dr. Garry M. Steil from Boston Children’s Hospital, Boston, Massachusetts, told Reuters Health in an email.
In light of improvements seen with adults and older children treated with closed-loop therapy, Dr. Steil and colleagues performed a randomized crossover inpatient study comparing closed-loop therapy with standard open-loop insulin pump therapy in 11 children aged 2 to 6 years with type 1 diabetes.
Ten children were included in the final analysis published in the October 1 online Diabetes Care.
During closed-loop therapy, there was a tendency toward a higher mean time for nocturnal plasma glucose to be within the target range (5.3 hours) compared with open-loop therapy (3.2 hours), but the difference was not statistically significant (p=0.12).
Closed-loop therapy did, however, significantly reduce the amount of time spent over 300 mg/dL and the total area under the curve of glucose above 200 mg/dL. Five patients required additional overnight correction doses of insulin during open-loop therapy because of hyperglycemia.
The two treatments did not differ in the number of episodes of hypoglycemia or in the time spent below the target range or frankly hypoglycemic.
There were no differences between treatments in peak postprandial glucose concentrations, but prelunch blood glucose was significantly better with closed-loop therapy than with open-loop therapy (189 vs 273 mg/dL; p =0.009).
“Children, particularly young children, are most likely to benefit from an artificial pancreas as their insulin requirements are highly variable and the effect of hypoglycemia on neurological development is unknown,” Dr. Steil said.
“Closed-loop systems that are designed for adults may not be appropriate for younger children,” he pointed out.
“The biggest impediment to achieving an artificial pancreas is fear of hypoglycemia; i.e., the fear that the system may deliver too much insulin,” Dr. Steil added. “However, this same fear exists for open loop therapy, particularly pump therapy at night in children. The difference is that parents, and to some extent physicians, have become acclimatized to the level of fear and stress associated with open-loop nighttime control, whereas the risks associated with an automated system are largely unknown. What may be counterintuitive is that a fully automated system may be safer than the existing standard of care, or a hybrid partially closed-loop system. Controlled clinical studies are needed to address these questions.”
Dr. Nelly Mauras from Nemours Children’s Clinic and Mayo College of Medicine, Jacksonville, Florida, who has done research in this area, told Reuters Health by email, “This is a study entirely in an in-patient clinical research center setting with a physician making most of the insulin delivery adjustments decisions, so it was not fully automated. The next step is to begin these studies in a closely-monitored outpatient setting and sorting out the variability of the insulin doses under ‘free living’ conditions.”
That said, Dr. Mauras added, “Overall, studies like this offer hope that we are truly making strides towards an artificial pancreas even in the youngest patients with type 1 diabetes. This is exciting technological progress.”
SOURCE: http://bit.ly/UJ9dNo
Diabetes Care 2012
