Primary care CGM starts tied to lower A1c, fewer hospital visits

Clinical takeaway: Primary care clinicians can initiate CGM for patients with insulin-treated diabetes rather than waiting on endocrinology, a shift that may widen access where specialist care is scarce.

Diabetes drives a heavy load of avoidable hospital and emergency visits, with much of that burden landing in safety nets already stretched thin. A new cohort study suggests one tool clinicians are already familiar with can help to move that trend in a positive direction. Continuous glucose monitoring (CGM), the data suggest, may be effectively initiated in the primary care setting rather than waiting for an endocrinology referral.

Most diabetes care happens in primary care, not endocrinology, and the specialist shortage is widening. But CGM, recommended by the American Diabetes Association for anyone on insulin, is still prescribed mostly in specialty settings. Uptake also lags in underserved populations, including Black and Hispanic patients.

The glycemic benefit was sizable and durable. Initiators saw their A1c drop about 0.5 percentage points more than non-initiators at one year, a gap that held through two years. These were patients who started with poor control, near 9.5% on average, and the largest gains showed up in those with the highest baseline A1c. Overall, CGM initiation was tied to 13% fewer hospitalizations and 18% fewer ED visits over three years.

The pattern held across the groups where CGMs have been hardest to get. Hispanic and non-Hispanic Black patients, who made up most of the cohort, saw A1c and acute-care benefits in line with the overall results. So did patients managed entirely within primary care, with no endocrinology visits, whose gains matched those seen overall.

Uptake itself remained modest, however. Only 28% of eligible patients were prescribed CGM over three years, though that is up from 17% previously. The authors estimate that a 13% drop in hospitalizations, against a national average of roughly $14,000 per stay, could yield substantial population-level savings, though the study itself did not measure cost.

The study drew on EHR data from 8,502 insulin-treated, CGM-naive adults across 18 primary care clinics in Montefiore's Bronx safety-net network, followed from 2022 to 2025. Nearly half were Hispanic and a third non-Hispanic Black, and most were covered by Medicare or Medicaid. Researchers compared the 28% who were prescribed CGM by a primary care clinician against those who were not, adjusting for demographics, medications, and clinical history, and modeling repeat hospitalizations and ED visits rather than just first events.

What comes next is turning a prescribing signal into reliable practice. Because the study counted prescriptions rather than confirmed device use, the open question is how many patients actually get the sensor, keep wearing it, and act on the data, and what primary care needs to make that happen. The authors point to clinician training, patient education, and system-level support as the levers, and to prospective studies to test whether the gains hold when CGM is deployed deliberately rather than observed after the fact.

"These findings support expanding CGM implementation in primary care settings as a scalable strategy to improve diabetes outcomes and reduce acute care utilization, particularly in underserved populations," the authors conclude.

Source: Milosavljevic J, et al. (2026 Jul 6) JAMA Netw Open. Primary care-initiated continuous glucose monitoring in adults with insulin-treated diabetes