Continuous Glucose Monitoring, or CGM, is the process of measuring the amount of sugar (glucose) in your body every few minutes through a sensor that is placed under your skin. The continuous readings allow the system to use the data to predict the direction your glucose level is heading and will display that information as an arrow. With the actual value of your glucose, plus the arrow, you can make more informed decisions on your diabetes management.
How does CGM differ from testing with a blood glucose meter?
CGM systems available today measure glucose in the interstitial fluid – the fluid between your cells just under the skin. Since it is measuring glucose in a different part of your body, it will not be the same concentration as in your blood, but very similar. A blood glucose meter requires that you take a small sample of blood from your fingertip and place it on a test strip that’s inserted inside a meter. The meter provides a glucose value based on the amount of glucose in the blood sample at that moment. CGM measures the amount of glucose in interstitial fluid below your skin. To provide glucose values every few minutes, a sensor needs to be inserted just below your skin. The glucose level taken from your blood can be different from the glucose level in the fluid below your skin. With traditional CGM sensors, you must insert a new sensor through the skin every 7-14 days. With the new CGM implanted sensor, a new sensor is fully inserted under the skin for up to 90 days.
Is CGM better than testing with a meter?
One significant benefit of CGM is that it provides a “moving” picture of how your glucose levels change over time without continuous samples from fingersticks1. This makes it easier for you to see how diet, exercise and other health factors affect your glucose levels. It also provides alerts and alarms to let you know if your glucose levels are changing rapidly or approaching unsafe levels. Published research studies demonstrate a reduction in A1C without increased episodes of low blood glucose values with consistent use of CGM2.