Tight glycemic control reduces vascular complications but fails to preserve beta cell function in pediatric type 1 diabetes: JAMA

The study found that in both groups, stimulated C-peptide levels initially increased between baseline and 13 weeks after diagnosis and declined over the next nine months. "The 52-week C-peptide levels and the pattern were consistent with the natural history of C-peptide levels in the first year following the diagnosis," the researchers explained.

Following the immediate diagnosis of type 1 diabetes, near normalization of blood sugar levels has been suggested to preserve pancreatic beta cell function by glucotoxicity reduction. Previous studies have been hindered by an inability to achieve tight glycemic goals. To address this knowledge, Jennifer McVean from the University of Minnesota, Minneapolis, and colleagues aimed to find out the effectiveness of intensive diabetes management to attain near normalization of glucose levels on preserving pancreatic beta cell function in youth having newly diagnosed type 1 diabetes in a randomized, double-blind, clinical trial conducted at six centres in the US.

The study included youths with newly diagnosed type 1 diabetes aged 7 to 17 years randomized from 2020 to 2021 and completed their follow-up on September 15, 2022. Sixty-one were randomly assigned to intensive diabetes management, including the use of an automated insulin delivery system, or 52 to standard care, including the use of a continuous glucose monitor, as part of a factorial design in which people weighing 30 kg or more were also assigned to receive either oral verapamil or placebo.

A mixed-meal tolerance test–stimulated C-peptide area under the curve (a measure of pancreatic cell function) was determined 52 weeks from diagnosis (primary outcome).

The study revealed the following findings:

• Among 113 participants (mean age, 11.8 years; 43% were females; mean time from diagnosis to randomization, 24 days), 96% completed the trial.
• In the intensive management group, there was a decrease in the mean C-peptide area under the curve from 0.57 pmol/mL at baseline to 0.45 pmol/mL at 52 weeks, and in the standard care group, it decreased from 0.60 to 0.50 pmol/mL (treatment group difference, −0.01).
• In the intensive management group, the mean time in the target range of 70 to 180 mg/dL, measured with continuous glucose monitoring, was 78% at 52 weeks versus 64% in the standard care group (adjusted difference, 16%).
• One severe hypoglycemia event and one diabetic ketoacidosis event occurred in each group.

"Intensive diabetes management in youth with newly diagnosed type 1 diabetes achieved excellent glucose control but did not impact the decline in pancreatic C-peptide secretion at 52 weeks," the team concluded.

Reference:

McVean J, Forlenza GP, Beck RW, et al. Effect of Tight Glycemic Control on Pancreatic Beta Cell Function in Newly Diagnosed Pediatric Type 1 Diabetes: A Randomized Clinical Trial. JAMA. Published online February 24, 2023. doi:10.1001/jama.2023.2063