Beyond the Sensor: The Potential Impact of Continuous Glucose Monitoring Alerts on Glycaemic Control

Why CGM alert settings matter Continuous glucose monitoring (CGM) is now standard care for people with type 1 diabetes (T1D) and many individuals with insulin-treated type 2 diabetes (T2D), supported by evidence that it improves glycaemic management. Real-time CGM systems offer multiple customizable alerts, including high-glucose, low-glucose, urgent-low and rate-of-change alarms. However, there is comparatively little evidence to guide clinicians on how these should be configured. This is particularly relevant in primary care, where CGM prescribing is increasing but familiarity with device-specific alert settings may vary. In this 2026 JAMA Network Open research letter, Zheng and colleagues investigated whether the use and thresholds of CGM alerts were associated with clinically important glucose metrics. Their findings suggest that alert configuration is not simply a usability preference: different settings may be associated with distinct—and sometimes competing—effects on hyperglycaemia and hypoglycaemia.