A continuous glucose monitoring system can help a person with diabetes (PWD) and the health care provider identify the causes of varying glucose levels that fingersticks alone are unable to accomplish. A fingerstick alone is unable to capture all of the factors that can interfere with blood glucose levels. The monitoring system serves as a tool to help reach a solution for healthier ranges of glucose levels.
What is a continuous glucose monitor?
A continuous monitor is a small device that can be worn to constantly capture glucose levels without having to perform a fingerstick. CGM systems can read glucose levels every one to five minutes.
Benefits of a continuous monitor
Wearing a monitor can help decrease hypoglycemia episodes. It can alert the PWD of rising or decreasing glucose levels and show the effects of food, activity, stress, illness, and medications, as well as help the provider in making medication adjustments and help solve an unmatched A1c with non-corresponding glucose levels.
Different types of monitors
There are two major differences in monitors, one is the professional that is owned by a licensed healthcare provider and the other is a personal monitor that is owned by the patient.
Professional and personal monitors
There are three professional continuous glucose monitors:
FreeStyle Libre Pro
These are owned by a healthcare provider for a patient to wear for monitoring glucose patterns for a 3-14-day time frame. While the patient is wearing these, they may or may not be aware of the results depending on the monitor used; this is considered blinded and unblinded. To receive the most benefit the patient is asked to keep food and blood sugar records and to continue with their normal routine. In some of the CGM systems an alarm can be set. To interpret the data with the patient an appointment is made for a return visit. It is possible to have a virtual visit, depending on the device and insurance coverage.
A personal continuous glucose monitor is chosen by the patient from among four brands:
DexCom G6 can be integrated with Tandem T:slim X2 insulin pump.
Medtronic Guardian Connect and the Guardian 3 that can be integrated with the insulin pump
Eversense implantable CGM.
The monitors can be worn for 7 to 14-days except for the Eversense which can be worn for up to a 3-month timeframe. Personal CGM’s can be used long term. The personal monitors may or may not have an alarm depending on the brand. Insulin dosing is approved for some CGM systems that are read in real-time. Also, some have data sharing capability with a mobile app for a friend or family member.
How do CGM systems work?
CGM systems have three main components for most brands:
Once attached, the sensor is almost unnoticed by the user. The data from the sensor is read from the receiver which in some cases can be a smart phone that is using the brand’s app. Once the sensor is in place and calibrated, it can begin to monitor glucose levels. When viewing, the user can see if the glucose is stable or if the level is trending up or down slowly or quickly; therefore, the user has time to respond to prevent a hypo or hyperglycemic event. They can also learn what may have lead to possible fluctuations to help make diabetes self-management decisions.
Where is a CGM worn?
Depending on the brand, the CGM sensor can be worn on the abdomen or the back of the arm. Some brands have an auto-injector for easy insertion.
Checking with your insurance company is recommended for professional and personal monitors. Commercial insurance companies and Medicare cover for the service by the professional and for the personal device depending on the individual plan. Type 1 and 2 are covered depending on guidelines for number of finger sticks and multiple daily injections. In some cases, if a personal CGM isn’t covered, the service for professional monitor usage, may be.