Continuous Glucose Monitoring for Adults With Type 2 Diabetes Not Using Insulin: Insights From the CONNECT Trial

Continuous glucose monitoring (CGM) significantly improves glycemic control in adults with type 2 diabetes who do not use insulin, according to findings from the CONNECT trial presented at the American Diabetes Association Scientific Sessions. The 26-week study demonstrated that participants using CGM achieved greater reductions in HbA1c and spent more time in their target glucose range compared to those receiving standard care.

How CGM Affects HbA1c Levels

The CONNECT trial, a randomized controlled study conducted at 22 primary care practices across the U.S., followed 283 adults with type 2 diabetes who were not on insulin therapy. According to Thomas W. Martens, MD, medical director at the International Diabetes Center, participants using a Dexcom G7 device saw their HbA1c levels drop from 8.8% to 7.2% over 26 weeks. In contrast, the standard care group experienced a smaller decrease, moving from 8.7% to 8%.

The researchers reported a 0.9 percentage point difference between the two groups, a result that reached statistical significance (P < .001). Notably, 82% of those using CGM achieved an HbA1c improvement of at least 0.5%, compared to 56% of participants in the routine care group. These benefits were observed consistently across various baseline HbA1c levels, with the most significant improvements occurring in individuals who started the trial with the highest baseline levels.

Impact on Time in Range

Beyond HbA1c, CGM users experienced measurable improvements in their time spent within the target glucose range of 70 mg/dL to 180 mg/dL. Dr. Martens reported that CGM users spent 21% more time in this target range, which equates to approximately five additional hours per day. These improvements were rapid, appearing within the first week of use and remaining consistent throughout the 26-week study period.

Clinical Considerations for Non-Insulin Therapies

Many participants in the study were managing their diabetes with non-insulin therapies, including metformin, GLP-1 receptor agonists, and SGLT2 inhibitors. Data from the trial showed that the benefits of CGM were sustained regardless of the specific glucose-lowering medication used. Dr. Martens noted that the combination of GLP-1 receptor agonist therapy and CGM produced the most significant treatment differential, suggesting that real-time glucose feedback may enhance the effectiveness of these medications.

Safety and Future Applications

The study reported no serious adverse events in either the CGM or standard care groups. Given these results, researchers suggest that CGM should be considered as a standard option for a broader population of adults with type 2 diabetes, extending beyond those who rely on insulin. By providing real-time feedback, CGM systems encourage lifestyle modifications and help patients better understand how their nutrition and daily habits affect their glucose levels.

Key Takeaways

• Improved Glycemic Control: CGM use led to a 1.6 percentage point reduction in HbA1c over 26 weeks compared to 0.7 percentage points with standard care.
• Increased Time in Range: Participants using CGM spent 21% more time in the target glucose range, with benefits appearing within the first week.
• Broad Applicability: The study indicates that CGM is effective for patients on various non-insulin therapies, including metformin, GLP-1 agonists, and SGLT2 inhibitors.
• Safety Profile: No serious adverse events were documented during the 26-week trial period.

As diabetes management continues to evolve, the integration of CGM technology offers a promising path for those not currently using insulin to achieve more stable blood glucose levels and better long-term health outcomes.