Continuous glucose monitors (CGMs)are monitoring devices people with diabetes use.
They are both used as a replacement for blood glucose testing to provide real-time data for people withdiabetes.
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What Are Continuous Glucose Monitors?
Getty Images /BSIP/ Contributor
CGMs are wearable devices that are applied to the skin and provide continuous real-time access to blood sugar readings.
CGM data can also help providers personalize treatment plans for their patients.
They are typically recommended for use in those who requireinsulinto manage their diabetes.
Types of CGM
CGM types are classified based on how they store and display blood sugar information.
CGM Components
CGMs consist of a sensor, a transmitter, and a receiver.
Sensors measure the glucose levels of fluid surrounding your bodys cells.
The glucose levels of this fluid closely mimic glucose levels in the blood.
Sensors are for temporary use and must be replaced as directed.
The sensor connects with the transmitter, which wirelessly transmits the data to a receiver or compatible smart unit.
This means that, for the most part, there’s no need for frequent finger sticking.
However, some CGM models require a finger stick with a glucose meter to help ensure data accuracy.
CGMs are durable and can be worn throughout the day.
They do not need to be removed while exercising, showering, or sleeping.
Examples of available CGMs include Dexcom and FreeStyle Libre, two commonly used CGM systems.
What Is Dexcom?
Dexcom’s CGM systems include sensors for placement on the back of the arm or lower abdomen.
They also include the option of placing sensors on the upper buttocks when used in children.
The sensors may be used for up to 10 days and do not require calibration.
Both systems have smartphone capabilities and applications for data monitoring and sharing.
Available Dexcom CGM products include:
Dexcom CGM products require a prescription.
What Is FreeStyle Libre?
Abbott’s FreeStyle Libre CGM systems include sensors intended for placement on the back of the upper arm.
It can be used for up to 15 days, setting it apart from the other Libre sensors.
Like Dexcom’s, each system has smartphone capabilities and data monitoring and sharing applications.
However, there are some key differences between Dexcom and FreeStyle Libre.
Glucose readings update automatically.
The Libre 2 Plus connects to the Tandem t:slim X2 insulin pump and corresponding mobile app.
Both Dexcom and FreeStyle Libre can be safely used in children as young as 2 years.
Which Is More Accurate?
Both Dexcom and Libre can provide reliable and precise continuous glucose monitoring.
Factors such as proper sensor use and calibration, proper insertion technique, and sensor location can influence accuracy.
A recent clinical trial evaluated the accuracy of one of each of the Dexcom and FreeStyle Libre CGM systems.
The study investigators compared their CGM readings with blood sugar readings.
Research your options and discuss them with your diabetes care provider.
CGM data should be monitored under the supervision of a healthcare provider.
Does Insurance Cover CGMs?
Some plans may cover certain CGM brands or models, while others may not.
Review your insurance policy and familiarize yourself with what your insurance covers.
Obtaining CGM readings can also be less painful than using a traditional blood glucose monitor.
Both adults and children can use Dexcom and Freestyle Libre with a valid prescription.
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