Continuous glucose monitoring in type 2 diabetes benefits people not on insulin, CONNECT trial shows
Presenter: Thomas W. Martens, MD, International Diabetes Center, Minneapolis, MN
CGM for Adults with Type 2 Diabetes Not on Insulin Therapy: The CONNECT Randomized Controlled Trial. Presented June 6, 2026.
Continuous glucose monitoring (CGM) led to significantly lower hemoglobin A1c in adults with type 2 diabetes who are not treated with insulin, according to results of the first randomized trial to provide high-grade evidence supporting CGM in this large, mostly primary-care population.
Over 26 weeks, patients on CGM had an average hemoglobin A1c reduction of 1.6 percentage points, 0.9 points more than with routine care, and spent about 5 more hours per day in the target glucose range, according to the CONNECT trial results, presented at the American Diabetes Association 2026 Scientific Sessions.
A clinically meaningful hemoglobin A1c reduction of at least 0.5 percentage points was reached by 82% of participants using CGM, and the benefit extended across every subgroup, including patients already taking a glucagon-like peptide 1 (GLP-1) receptor agonist or a sodium-glucose cotransporter 2 (SGLT-2) inhibitor, according to the authors.
The results are the first and only level-A evidence of a strong CGM benefit in type 2 diabetes managed without insulin, according to senior author Roy W. Beck, MD, PhD, of the Jaeb Center for Health Research.
“Level-A evidence, the highest level of evidence graded by the ADA, has historically driven meaningful changes in standards of care,” Dr. Beck said in a statement.
Strong evidence already supports CGM for people who use insulin, in both type 1 and type 2 diabetes, the authors noted. Small trials had suggested a benefit in patients who manage type 2 diabetes without insulin, but a fully powered randomized trial was needed to provide higher-level evidence, which is why the investigators undertook CONNECT in primary care.
“Since many of the patients with type 2 diabetes who use oral or noninsulin injectable therapies are seen in primary care settings, continuous glucose monitoring provides an opportunity to close a visible care gap,” said co-author Thomas W. Martens, MD, of the International Diabetes Center.
CONNECT screened 440 adults at 22 primary care practices in the United States and randomly assigned 283 who had type 2 diabetes not treated with insulin and a hemoglobin A1c of 7.5% or higher to use a CGM (Dexcom G7; Dexcom, Inc, San Diego, CA) or to receive routine care with self-monitoring of blood glucose for 26 weeks. All participants received diabetes education on diet and exercise, were given a blood glucose meter, and continued their prestudy glucose-lowering medications. The primary outcome was the change in hemoglobin A1c from baseline to 26 weeks.
A total of 265 participants completed the trial. At baseline, their mean age was 60 years, 32% were of a minority race or ethnicity, and their mean hemoglobin A1c level was 8.8%, with 31% at 9% or higher. Background therapy was heterogeneous, with 40% of participants taking an incretin-based agent (a GLP-1 receptor agonist or a GLP-1/glucose-dependent insulinotropic polypeptide [GIP] receptor agonist) and 37% taking an SGLT-2 inhibitor.
At 26 weeks, hemoglobin A1c had fallen by an average of 1.6 percentage points in the CGM group, a reduction 0.9 percentage points greater than with routine care. Among participants who entered with a hemoglobin A1c above 10%, it dropped by an average of 3.1 percentage points with CGM, 2.1 points more than routine care. By 26 weeks, 68% of CGM users had reached a hemoglobin A1c below 7.5% and 46% had reached below 7.0%.
Time in the 70-to-180 mg/dL target glucose range averaged 62% with CGM compared with 41% with routine care at 26 weeks, translating into a difference of about 5 hours per day. The improvement emerged within the first 1 to 4 weeks and was sustained through 26 weeks, according to the authors.
The benefit was additive across medication regimens. Even patients not taking any glucose-lowering drugs saw their hemoglobin A1c fall by 2.4 percentage points with CGM, and adding CGM produced a 1.4 percentage point reduction in patients taking a GLP-1 receptor agonist and a 1.8 percentage point reduction in those taking an SGLT-2 inhibitor, each greater than in the corresponding routine-care group.
Participants using CGM also reported greater satisfaction and less diabetes-related distress than those receiving routine care, along with a median device wear time of 97% over the 26 weeks.
The CONNECT trial is comparable in scale to earlier randomized trials such as DIAMOND and MOBILE that helped establish CGM as standard of care for people who use insulin, according to Dexcom, which sponsored the study.
The findings arrive as the ADA updated its standards of care to recommend CGM for adults with type 2 diabetes on any treatment regimen in which it helps in managing the condition.
A 6-month extension phase of CONNECT is underway and is expected to show whether the benefits are sustained through 12 months, according to the authors.
Disclosures
CONNECT was sponsored by Dexcom, and the trial evaluated the Dexcom G7 CGM. Both Drs. Beck and Martens reported disclosures (consulting and/or research support). Full personal financial disclosures for the authors were listed in the online.
References
Oser T, Beck RW, Martens T, et al. CGM for adults with type 2 diabetes not on insulin therapy: the CONNECT randomized controlled trial. Abstract 1170-OR. Diabetes 2026; 75(suppl 1). Presented at the ADA 2026 Scientific Sessions, June 6, 2026.
American Diabetes Association. 82% of adults with type 2 diabetes not on insulin improve blood glucose levels with continuous glucose monitoring. Press release. June 6, 2026.
DexCom, Inc. Dexcom reaffirms CGM benefits for all people with diabetes and continues momentum toward earlier stage intervention and preventative care at ADA 2026. Press release. June 4, 2026.
American Diabetes Association. Summary of revisions: standards of care in diabetes, 2026 (recommendation 9.25). Diabetes Care 2026; 49(suppl 1):S6–S22. doi:10.2337/dc25-SREV