CGM's A1C impact in CONNECT trial rivals effective non-insulin treatments: Thomas Martens, M.D. | ADA 2026

Continuous glucose monitoring (CGM) produced A1C reductions on par with some of the most potent non-insulin diabetes medications in the CONNECT randomized controlled trial, Thomas Martens, M.D., of HealthPartners told Managed Healthcare Executive after presenting the data at the 2026 American Diabetes Association Scientific Sessions.

Martens said CONNECT fills a gap in the evidence. CGM is well studied in people who use insulin, but the large group managing type 2 diabetes without insulin had not been rigorously evaluated. The trial randomized almost 300 participants nearly evenly to CGM or routine care, defined as finger-stick monitoring used as patients found helpful, and followed both arms for 26 weeks. The primary outcome was change in A1C.

Both groups improved, but the CGM arm did better. Participants using CGM lowered A1C from a baseline of 8.8% to about 7.2%, a 1.6% reduction. The routine care group fell from 8.7% to roughly 8%, about a 0.7% reduction. The 0.9% between-group difference drove much of the interest in the results.

To frame the magnitude, Martens pointed to the UK Prospective Diabetes Study, where a 0.9% A1C reduction was tied to roughly a 25% drop in microvascular complications, including diabetic kidney disease, retinopathy and neuropathy.

He also compared CGM directly to drug therapy: an SGLT2 inhibitor might lower A1C about 0.7%, while GLP-1 therapy can deliver roughly 1.5% to 2%. CGM's reduction sits among the more potent non-insulin agents, he said, suggesting clinicians and payers can think of it as comparable to adding a medication for a large, understudied population.