Time in range, other CGM metrics linked to diabetic retinopathy risk in type 1 diabetes

Continuous glucose monitoring means using a device to automatically estimate your blood glucose level, also called blood sugar, throughout the day and night. According to findings published in Diabetes Technology & Therapeutics, providers can use continuous glucose monitoring metrics as well as HbA1c, a measure of average blood sugar, to assess diabetic retinopathy risk for adults with type 1 diabetes. Specifically, the researchers found that each 5 percentage point decrease in time in range increased the odds for diabetic retinopathy by 24%. (Time in range is the amount of time you spend in the target blood glucose range—between 70 and 180 mg/dL for most people.) Higher time above range was also linked to an increase in diabetic retinopathy risk.

Viral N. Shah, MD, who led the study, said a prospective study with prespecified outcomes and a larger sample size, similar to the design of the Diabetes Control and Complications Trial (DCCT), would be best to further analyze associations between CGM metrics and diabetes complications.  “The main question is around the funding of a new DCCT-like study, it would cost a lot to do DCCT again,” Shah said. “Therefore, we designed this mini DCCT-like study. I hope to see our findings being replicated by others.”

Source: Michael Monostra, Healio Endocrine Today, January 9, 2023; see source article