Intermittently Scanned and Real-Time Continuous Glucose Monitoring for People With Diabetes

Key Messages

• Continuous glucose monitoring is a method of glucose testing in which a sensor is inserted into the skin and continuously monitors interstitial glucose concentrations. Real-time continuous glucose monitoring (rtCGM) systems automatically measure glucose and display a recent glucose value. Intermittently scanned continuous glucose monitoring (isCGM) systems require the person using the system to scan the sensor to display glucose information.
• The evidence of the comparative effectiveness of isCGM versus rtCGM for improving time in range, time above range, A1C, and quality of life in people with type 1 diabetes is uncertain. Evidence from some studies suggested there was a significant benefit favouring rtCGM versus isCGM for these outcomes, whereas other studies found no significant differences between treatment groups.
• Evidence suggested that people with type 1 diabetes using rtCGM spent significantly less time below range/time in hypoglycemia than those using isCGM.
• The evidence of the comparative safety of isCGM versus rtCGM in people with type 1 diabetes is limited and uncertain. Evidence from 1 study suggested that severe hypoglycemic events were more frequent in those using isCGM. In other studies, there were no severe hypoglycemic events in either treatment group.
• No studies were identified that evaluated the comparative effectiveness of isCGM versus rtCGM in people living with type 2 diabetes or gestational diabetes.