Study: Hybrid Closed-Loop Insulin Therapy Improves Glycemic Control in Type 1 Diabetes

New research has found that a hybrid closed-loop insulin therapy improved glycemic control in adolescents and young adults with type 1 diabetes, according to an article published in Diabetes Technology & Therapeutics (DTT).¹

Despite improvements in care for type 1 diabetes, the study authors noted that the majority of youth with the disease still fail to meet glycemic control targets. Closed-loop insulin delivery may help improve glycemic control, although outcomes data are scarce in pediatric and young adult populations. Short-term studies in monitored clinical settings and at diabetes camps have found that closed-loop systems can increase time in range (TIR) and reduce both hyperglycemia and hypoglycemia.¹

Furthermore, the authors said a retrospective study of a clinically available closed-loop control (CLC) system suggested that successful use was associated with increased TIR and reduced HbA1c in youth, although many participants discontinued use of the hybrid closed-loop system within the first 6 months. According to the study authors, they cited difficulty with calibrations, alarms, expense, and the workload required to ensure correct function as reasons for discontinuation.¹

In the study, called the International Diabetes Closed-Loop (iDCL) trial, participants with a mean age of 17 years were randomly assigned to a CLC insulin delivery system or a sensor augmented pump (SAP) with a continuous glucose monitoring system over a 6-month period. Both groups attended follow-up visits at 2, 6, 13, and 26 weeks and were contacted by telephone at 1, 4, 9, 17, and 21 weeks. Data-driven optimization of pump settings could be made at the 2-, 13-, and 26-week visits.¹

According to the findings, the TIR for glycemic control increased by 13% for the CLC group compared to a decrease of 1% in the SAP group. The investigators said this resulted in a group difference of plus 3.1 hours per day. This change also reflected a reduction in time spent at greater than 180 mg/dL, and the authors said the use of CLC was especially effective at increasing time in range overnight.¹

“Notably, we found that this sample of adolescents and young adults successfully used the CGM more than 90% of the time during the 6-month trial and the closed-loop system was active 89% of the time,” said John Lum, MS, of the Jaeb Center for Health Research, in a press release.²

According to the study authors, reportable adverse events (AEs) included serious AEs, AEs occurring in association with a trial device or procedure, severe hypoglycemia, diabetic ketoacidosis, and hyperglycemia with ketonemia for which a health care provider was contacted.¹

“Multiple Automated Insulin Delivery systems using different algorithms have been developed in the past decade for patients with type 1 diabetes. Almost all of the systems have shown significant reductions in nocturnal hypoglycemia,” said Satish Garg, MD, editor-in-chief of Diabetes Technology & Therapeutics, in a press release. “The iDCL multicenter trial done in young adults and adolescents with [type 1 diabetes] reported in this issue of DTT further advances the use of hybrid closed-loop system by increasing the time-in-range, especially during the night.”²

REFERENCES

• Isganaitis E, Raghinaru D, Ambler-Osborn L, et al. Closed-Loop Insulin Therapy Improves Glycemia Control in Adolescents and Young Adults: Outcomes from the International Diabetes Closed-Loop Trial. Diabetes Technology & Therapeutics; January 21, 202 https://www.liebertpub.com/doi/10.1089/dia.2020.0572. Accessed January 29, 202
• Hybrid Closed-Loop Insulin Therapy Improves Glycemic Control [news release]. Mary Ann Liebert Publishers; January 26, 2021. https://home.liebertpub.com/news/hybrid-closed-loop-insulin-therapy-improves-glycemic-control/3810. Accessed January 29, 2021.