A Simpler Way to Track Beta Cell Function in Early Type 1 Diabetes

People with islet autoimmunity—antibodies against the cells that make insulin—are at high risk for Type 1 diabetes, but many don't need insulin treatment right away. Tracking how well their remaining beta cells work is important for understanding disease progression and timing interventions.

Currently, the best way to measure beta cell function is the oral glucose tolerance test (OGTT), where patients drink glucose solution and doctors take multiple blood samples over three hours. This test is accurate but invasive and inconvenient, especially for young people who may need repeated monitoring.

Researchers wondered whether the data already collected by continuous glucose monitors—devices many people wear to track glucose in real time—could be used to estimate beta cell function without all the blood draws.

They enrolled 24 participants (median age about 17 years) with islet autoimmunity who weren't yet on insulin. Eighteen participants completed the full study. While wearing a blinded CGM, each person had a standard 3-hour OGTT with blood samples. The researchers then compared how well the CGM-based estimate of beta cell function matched the traditional blood-test-based measurement.

The results were promising: the CGM method and the traditional OGTT showed very strong agreement (correlation of 0.90), suggesting the CGM approach could be a reliable alternative.

A year later, researchers brought participants back for repeat CGM monitoring. They wanted to know whether early beta cell changes could predict later glucose control problems.

They found that people whose baseline CGM-based beta cell estimate was lower had more time with high glucose levels one year later. This suggests that the CGM measurement captured real information about how quickly beta cell function was declining—information that was predictive of future glucose patterns.

This is important because it means doctors could potentially spot problems earlier and more simply, using data patients are already generating with their devices.

This study was small and involved mostly young participants. Larger studies will be needed to confirm these findings across different age groups and to understand how this approach could fit into clinical monitoring for people with early-stage Type 1 diabetes.

If further research supports these results, CGM-based beta cell monitoring could become a practical tool for tracking disease progression without the burden of frequent oral glucose tolerance tests.

Source: Diabetologia. Evidence type: PubMed indexed literature. Type1Cure is an information and intelligence hub, not a medical advice service. This article summarizes published research and does not provide diagnosis, treatment, or personal medical guidance. Always talk to your own care team before changing anything about your Type 1 diabetes management.