Study: CGM use lowers A1C in adults with Type 2 diabetes

NEW ORLEANS – Adults with Type 2 diabetes who are on of continuous glucose monitoring (CGM) but who are not on insulin saw substantially reduced hyperglycemia, resulting in a large reduction in A1C compared with a routine care control group, according to new researchers presented at the 2026 Scientific Sessions of the American Diabetes Association (ADA) in New Orleans. 

The study found that CGM was associated with a substantial reduction in hyperglycemia, resulting in a 0.9% greater A1C reduction after six months in the CGM group compared with the Routine Care control group. Time in the glucose target range of 70 to 180 mg/dL was a five hours per day greater with CGM than with routine care. Participants in the CGM group expressed greater satisfaction with glucose monitoring and reduced distress related to diabetes compared with the routine care group.

"Since many of the patients with type 2 diabetes who use oral or non-insulin injectable therapies are seen in primary care settings, continuous glucose monitoring provides an opportunity to close a visible care gap," said Thomas W. Martens, MD, co-author of the study. "As the first major randomized controlled trial evaluating CGM in individuals with type 2 diabetes not using insulin, these findings can help reshape diabetes management and expand treatment options for patients, improve glucose levels and A1C management for clinicians, and ultimately reduce diabetes-related complications."

The CONNECT randomized controlled trial was a multicenter study conducted across 22 primary care practices in the U.S. and included 283 adults with Type 2 diabetes not on insulin (mean age 60; 32% racial or ethnic minority participants; A1C 7.1% to 14.9%). The trial evaluated the impact of CGM on blood glucose management and A1C levels over 26 weeks. At baseline, mean A1C was 8.8%, with 31% of participants having an A1C ≥9%. In addition, 37% of participants were using an SGLT2 inhibitor, an oral medication that helps remove excess glucose through the urine, while 40% were using an incretin-based medication, such as a GLP-1-based medication. Participants were randomly assigned to either use a CGM device (Dexcom G7) or receive routine care with standard blood glucose meter testing.