Freestyle Libre Sensor vs. Dexcom: CGM Function, Cost, and Accuracy

Checking your blood sugar, or glucose, on a daily basis is an important element of controlling type 1 and 2 diabetes for many people.

Until recently, this was done at home with finger pricks and test strips using self-monitoring blood glucose (SMBG) devices.
New technology, such as continuous glucose monitors (CGMs), makes it easier to track your blood sugar levels without the need for frequent finger pricks. These devices are being used by an increasing number of individuals, particularly children. Each monitor has a wearable sensor that adheres to your skin; the location of the sensor and how long you can wear it vary by device. It operates by collecting samples and creating sugar readings with a painless microneedle.
CGMs do not require blood samples, unlike traditional metres. Instead, they measure the quantity of glucose in the interstitial fluid, which is the fluid right beneath the skin. But which CGM choices are the best and how do they compare?
The Dexcom G6 and Abbott FreeStyle Libre are the two most popular CGMs in the UK. In this article, we'll go through what CGMs are, how they work, and the distinctions between Dexcom and FreeStyle Libre, two of the most well-known brands.

How Does Freestyle Libre Compare with Dexcom G6?

Abbott Diabetes originally introduced the FreeStyle Libre in the United States in 2017, and the FreeStyle Libre 2 has been marketed since mid-2020. It has been approved by the FDA for use in children as young as four years old, as well as adults with type 1 or type 2 diabetes.
 
On the other hand, since its beginnings in 2005, Dexcom G6 has been producing CGM technology, and with each upgrade, its sensors are meant to become more accurate, reliable, and convenient. Since 2018, the current Dexcom G6 model, which is suitable for people aged 2 and up, has been released. Dexcom G6 has maintained its position as the most popular full-featured CGM available, from its first model to the most recent mobile-connected gadget.

Freestyle Libre: Features & Working

The FreeStyle Libre 2 differs from the Dexcom G6 in that, while it is commonly referred to as a CGM, it is not meant to transmit real-time data. It is actually a "Flash Glucose Monitor," that requires manual swiping over the sensor to obtain glucose readings.

• Cost

The Abbott Freestyle Libre 2 is an affordable device that roughly costs around $2,300/year pre-insurance. That is why one of the main selling factors for FreeStyle Libre since its launch has been its price.

• 14-Day Sensor

To obtain the best possible results, the FreeStyle Libre 2 features a fully-disposable sensor with a sticky glue on the back side that keeps it adhered to your skin. Like the Dexcom G6 sensor, it is completely waterproof.
It's good for 14 days before you need a new sensor (4 days longer than Dexcom G6). Abbott's tech assistance, like Dexcom G6, can help you replace a sensor that isn't lasting as long as it should be.

• Warmup Time

Before it starts generating glucose data, FreeStyle Libre 2 requires a one-hour warmup period. That's an hour less than the Dexcom G6 competitor.

• No Fingersticks Required

Like the Dexcom G6, the FreeStyle Libre 2 is also an FDA-approved gadget with a fingerstick free sensor and great accuracy.

• Libre 2 Mobile App

Unlike the previous generation, the FreeStyle Libre 2 did not come with a smartphone app. However, the FDA approved the Libre 2 mobile app later on. It allows you to take and view glucose levels immediately on the connected smartphone.

• Data Analysis

The data can be evaluated on the reader or via the company's FreeStyle LibreLink software on a smartphone. However, the amazing thing about this software is that it allows up to 20 users to share data remotely, which is twice as many as the Dexcom G6.

• Interoperability

The FreeStyle Libre 2 is not currently compatible with any other diabetes devices, however it is being tested with others, such as Bigfoot Biomedical's upcoming connected insulin pen system.

• Accuracy

The current FreeStyle Libre gadget gets a total MARD score of 9.3 percent. According to clinical statistics, this indicates it isn't quite as accurate as the competitive Dexcom G6.

Dexcom G6: Features & Working

Made up of two simple parts, the Dexcom G6 is worn as a single unit on the body. The system's brain is this small grey plastic oval. Once implanted on your skin, it snaps into the sensor's clear plastic bracket.
Each transmitter has a three-month battery life and should be discarded once that time has passed. The G6 transmitter provides glucose measurements via Bluetooth (with a range of around 20 feet) every 5 minutes to a smartphone app or a separate handheld touchscreen receiver, where the user can view the data.

• Cost

The entire cost of any CGM system is determined on the user's requirements as well as the type of insurance coverage he or she has. Pre-insurance Dexcom G6 costs around $3,800 per year.

• 10-Day Sensor

Each sensor is packaged in a white and orange plastic auto-inserter. The sensor's tiny cannula is inserted into your skin with a simple push of a button, and the unit is adhered to your body with a built-in medical adhesive.
Water-resistant, the sensor can be worn in the shower or while swimming. The FDA has cleared it for use on the abdomen and upper buttocks. The sensor is designed to live for 10 days before shutting off, however sensors do occasionally fail early. In this scenario, the company will send a replacement to the customer.

• Warmup Time

The G6 sensor takes up to 2 hours to warm up and generate glucose data.

• Fingerstick Free Sensor

Despite the fact that the G6 is factory-calibrated and doesn't require any fingersticks to confirm a glucose level, some PWDs prefer to use a typical fingerstick metre to double-check their results. The G6 does allow users to "calibrate" the system by logging a fingerstick result if they so desire. This can occasionally assist in keeping the CGM on track.

• G6 Mobile App

Most G6 users no longer need a receiver and instead use the company's mobile app to control and display the CGM, which works with most iOS and Android phones. Depending on whether you're "In Range," "Low," or "High," the app's home screen displays a circle with your current real-time glucose level and the corresponding gray/red/yellow colour code.
Moreover, the circle displays an arrow that points in the direction thar you are trending. Below the circle is a graph with a dotted line that shows three hours' worth of glucose levels data.
The G6 also offers remote monitoring enabling you to see more than the last three hours' worth of CGM data. To see up to 24 hours of data, turn your phone horizontally and scroll backwards.

• Data Analysis

The Dexcom G6 mobile app allows users to view glucose trends over the previous 1, 3, 6, and 12 hours. The Dexcom CLARITY platform, on the other hand, can be used to review more complete data. You can access it online or on your phone by selecting the little green symbol in the top right corner of the horizontal view from the G6 mobile app. Users can also provide their healthcare providers access to their data.
What’s more, the Dexcom G6 app has a built-in capability that allows up to 10 authorised followers to analyse data and trends remotely and monitor a user's glucose readings in real time.

• Interoperability

The connection of Dexcom G6's CGM with insulin pumps like the Tandem t:slim to produce a "closed loop" system that can automatically change insulin doses based on glucose readings is currently exclusive to Dexcom G6. The Dexcom G6 will also be compatible with the new OmniPod 5 tubeless patch pump.

• Accuracy

The mean absolute relative difference is the standard measurement of CGM performance (MARD). The lower the number, the more accurate the measurement. According to clinical data, the Dexcom G6 has a MARD of 9% and maintains accuracy over the course of a sensor's wear.
According to the clinical research results, this is marginally more accurate than the FreeStyle Libre 2. Individual user experiences may vary, however many people with diabetes who have used both the Dexcom G6 and the FreeStyle Libre 2 report similar accuracy.

The Bottom Line

Both the Dexcom G6 and the FreeStyle Libre 2 have considerable benefits for glucose management, but each has its own set of advantages and disadvantages that may affect user decision. The Dexcom G6 is by far the most accurate and ergonomic full-featured CGM on the market, but the FreeStyle Libre is a more "low-key tool" with fewer and fully customizable alerts and alarms.
The Dexcom G6's mobile app and data-sharing capabilities provide you more alternatives, and the "Urgent" alarms are especially helpful for folks who have frequent hypoglycemia, especially overnight. While the FreeStyle Libre will soon be linked into automated systems with insulin pumps, the Dexcom G6 now has the advantage in terms of interoperability. For many people, insurance coverage is still the most important consideration in deciding which CGM to use, and the FreeStyle Libre presently leads because of its lower price.
To put it another way, insurance destroys people's hearts. There's often no rhyme or reason (when it comes to coverage decisions), and this affects which CGM someone can use, regardless of their preferences. As a result, if everyone had access to a CGM, it would revolutionise the diabetic world.