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Revolutionizing Diabetes Care with Advanced CGM Devices

Advanced continuous glucose monitoring (CGM) devices offer real-time glucose readings, eliminating frequent finger stick testing to monitor blood sugar levels.

Continuous glucose monitoring (CGM) devices have transformed diabetes management by enabling continuous and accurate real-time tracking of blood glucose levels. These minimally invasive wearables eliminate the need for frequent fingerstick testing and play a vital role in effective chronic condition management for individuals with diabetes, prediabetes, or gestational diabetes. 

By continuously monitoring glucose levels throughout the day and night, CGMs provide real-time data and trends to help people make informed treatment decisions. 

In the United States, several brands of CGMs are available, each with varying levels of reliability and accuracy. The choice of the most suitable brand often depends on factors such as personal preference, ease of use, cost, and insurance coverage. 

Personal CGM Devices 

Personal CGM devices are wearable devices used by individuals with diabetes to monitor their blood glucose levels continuously. They consist of a sensor inserted under the skin. This transmitter sends data wirelessly to a receiver or smartphone app and provides real-time glucose readings, trend analyses, and customizable alarms. They help users make informed decisions about their diabetes management and improve glycemic control. 

Personal FDA-approved CGM devices include Abbott’s FreeStyle Libre 2 and 3, Dexcom’s G6 and G7, Medtronic Diabetes’ Guardian Connect, and Senseonics’ Eversense E3. 

Abbott FreeStyle Libre 2 

The FreeStyle Libre 2 is a CGM system developed by Abbott that measures glucose levels in interstitial fluid (ISF), providing real-time data to the user. The sensor communicates wirelessly with a reader or compatible smartphone and features customizable high- and low-glucose alerts, helping users manage their diabetes more effectively. 

  • FDA Approval Date: June 12, 2020 
  • Glucose Reading Frequency: measures every min; records every 15 min 
  • Sensor Placement: back of the upper arm 
  • Sensor Size: 1.38 × 0.2 in. 
  • Approved Ages: 2 and older 
  • Cost: retails around $154 for two 14-day sensors 
  • Sensor Duration: 14 days 
  • Waterproof (up to 3.2 ft): 30 min
  • Data Sharing: up to 20 people
  • Transmitter Range: 20 ft 
  • Calibration: not required
  • Warm-up Time: 1 h
  • Overall MARD: 9.2% for adults; 9.7% for children 
  • Device Compatibility: certain Apple iOS and Android devices 

Abbott FreeStyle Libre 3 

Libre 3’s smaller size and matte finish offer enhanced comfort and minimized visibility. Unlike previous models, it holds data for longer periods, reducing the need for frequent scans. This innovation provides users instant access to glucose readings, offering more timely updates for improved diabetes management. 

  • FDA Approval Date: May 26, 2022 
  • Glucose Reading Frequency: every min 
  • Sensor Placement: back of the upper arm
  • Sensor Size: 0.1 × 0.8 in. 
  • Approved Ages: 4 and older 
  • Cost: retails around $154 for two 14-day sensors 
  • Sensor Duration: 14 days 
  • Waterproof (up to 3.2 ft): 30 min 
  • Data Sharing: up to 20 people 
  • Transmitter Range: 33 ft 
  • Calibration: not required
  • Warm-up Time: 1 h
  • Overall MARD: 7.9% 
  • Device Compatibility: specified Apple iOS and Android devices 

Dexcom G6  

The Dexcom G6 is a CGM system that measures glucose levels in ISF. The sensor communicates wirelessly with a receiver or compatible smartphone, providing real-time glucose readings. It also features customizable high- and low-glucose alerts, trend arrows indicating the direction and rate of glucose change, and the ability to remotely share data with caregivers or healthcare providers. Unlike other CGM systems, Decom's sensors require an overpatch. 

  • FDA Approval Date: March 27, 2018 
  • Glucose Reading Frequency: every 5 min 
  • Sensor Placement: abdomen (ages 2 and older) or upper buttocks (ages 2–17 years)
  • Sensor Size: 1.8 × 1.2 × 0.6 in.  
  • Approved Ages: 2 years and older 
  • Cost: retails around $450 for three 10-day sensors 
  • Sensor Duration: 10 days  
  • Waterproof (up to 8 ft): 24 h
  • Data Sharing: up to 10 people 
  • Transmitter Range: 20 ft 
  • Calibration: not required but advised
  • Warm-up Time: 2 h
  • Overall MARD: 9.0%  
  • Device Compatibility: specified Android and iOS devices, Dexcom receiver, Tubeless Omnipod 5 Automated Insulin Delivery System, Tandem t:slim X2 insulin pump, iLet Bionic Pancreas, Lily Tempo, and various third-party healthcare apps 

Dexcom G7 

Dexcom G7 offers several improvements over previous models, including a smaller, more discreet design, a longer wear duration of up to 14 days, and a simplified sensor insertion process. 

  • FDA Approval Date: December 7, 2022 
  • Glucose Reading Frequency: every 5 min 
  • Sensor Placement: back of the upper arm, abdomen (except during pregnancy), or upper buttocks (ages 2–6 only)
  • Sensor Size: 1.07 × 0.94 × 0.18 in. 
  • Approved Ages: 2 years and older 
  • Cost: retails for $150 per 10-day sensor 
  • Sensor Duration: 10 days + 12 h grace period 
  • Waterproof (up to 8 ft): 24 h
  • Data Sharing: up to 10 people 
  • Transmitter Range: 20 ft 
  • Calibration: not required
  • Warm-up Time: 30 min
  • Overall MARD: 8.2% for adults; 8.1% for children 
  • Device Compatibility: the latest Apple iOS and Android devices; Beta Bionics iLet, Tandem t:slim X2 insulin pump, Lily Tempo 

Medtronic Guardian Connect 

Medtronic Diabetes developed the Guardian Connect CGM system that includes a small sensor, Guardian Sensor 3, that is inserted under the skin to measure glucose levels in ISF. The sensor communicates wirelessly with a compatible smartphone, allowing users to view their glucose readings in real time through a dedicated mobile app. 

Guardian Connect gives users insights into their glucose trends, including rate of change and predictive alerts for high- and low-glucose levels. It also offers customizable alerts to notify users of potential high and low events.  

  • FDA Approval Date: March 8, 2018 
  • Glucose Reading Frequency: every 5 min
  • Sensor Placement: abdomen (2 and older), buttocks (2–13), or back of the upper arm (14 and older)
  • Sensor Size: 1.41 × 1.13 × 0.38 in. 
  • Approved Ages: 14 and older for Guardian 3; 7 and older for Guardian 4 
  • Cost: retails around $300 per month 
  • Sensor Duration: 7 days 
  • Waterproof (up to 8 ft): 30 min
  • Data Sharing: up to 5 people via the Carelink app
  • Transmitter Range: 20 ft  
  • Calibration: necessary up to 4 times a day 
  • Warm-up Time: 2 h 
  • Overall MARD: 8.7% 
  • Device Compatibility: specified Android and iOS devices, Medtronic receiver, CareLink software, InPen 

Senseonics Eversense E3 

The Eversense E3 CGM system, developed by Senseonics, consists of a small sensor implanted under the skin by a healthcare professional. The sensor continuously measures glucose levels in the ISF, providing real-time data to the user. 

One of the distinguishing features of the Eversense E3 CGM is its long-term wearability, as the sensor can remain implanted for up to six months before needing replacement. The system also includes a wearable transmitter that communicates wirelessly with the sensor to relay glucose data to a compatible mobile app on the user's smartphone. Unlike other systems, this transmitter can be removed for short periods without wasting the sensor. 

The Eversense E3 CGM also offers customizable alerts for high- and low-glucose levels, trend information to help users understand their glucose patterns, and the ability to share data with healthcare providers for remote monitoring and management. 

  • FDA Approval Date: March 29, 2023 
  • Glucose Reading Frequency: every 5 min
  • Sensor Placement: back of the upper arm
  • Sensor Size: 0.1 × 0.7 in. 
  • Approved Ages: 18 and older 
  • Cost: retails for $2,900–3,500 per year 
  • Sensor Duration: up to 6 months 
  • Waterproof (up to 3 ft): 30 min 
  • Data Sharing: up to 5 people via the Eversense NOW app 
  • Transmitter Range: 25 ft 
  • Calibration: utilizes a calibration algorithm to track sensor glucose sensitivity and notifies users when calibration is necessary; users cannot manually adjust the calibration frequency 
  • Warm-up Time: 24 h
  • Overall MARD: 8.5% 
  • Device Compatibility: Apple iOS (12.X–17.X), Android (8.0–14.X), and Apple Watch (5.X.X–10.X.X) 

Professional CGM Devices 

Professional CGM devices are medical tools healthcare professionals use to monitor patients' glucose levels over an extended period. Unlike personal CGM devices worn and operated by individuals, professional CGM devices are typically placed and managed by medical professionals in clinical settings.

These devices are often used for short-term monitoring to gather comprehensive glucose data for diagnostic purposes, treatment optimization, and tracking glucose patterns.

Professional FDA-approved CGM devices include Abbott FreeStyle Libre Pro and Dexcom G6 Pro. 

Abbott FreeStyle Libre Pro 

The FreeStyle Libre Pro is a CGM sensor reader that stays in the clinic, where healthcare professionals can use it to view glucose data. One reader can scan multiple patients, minimizing waiting time and scheduling issues. 

  • FDA Approval Date: September 28, 2016 
  • Glucose Reading Frequency: every 15 min 
  • Sensor Placement: back of the upper arm 
  • Sensor Size: 1.38 × 0.2 in. 
  • Approved Ages: 18 and older 
  • Cost: system kit containing one reader and four 14-day sensors retails for $299
  • Sensor Duration: 14 days 
  • Transmitter Range: 20 ft 
  • Calibration: not required 
  • Waterproof (up to 3 ft): 30 min; not recommended for use above 10,000 ft 
  • Warm-up Time: 1 h
  • Overall MARD: 14.8% 
  • Device Compatibility: certain Apple iOS and Android devices 

Dexcom G6 Pro 

The Dexcom G6 Pro is an upgraded diabetes management tool used by medical practices, offering real-time patient data access and retrospective data review for healthcare providers. 

  • FDA Approval Date: October 7, 2019 
  • Glucose Reading Frequency: every 5 min 
  • Sensor Placement: abdomen (2 years and older) or the upper buttocks (2–17 years) 
  • Sensor Size: 1.2 × 1.8 in. 
  • Approved Ages: 2 and older 
  • Cost: starter kit retails for $299 for four Dexcom G6 Pro CGM System units, one Dexcom G6 Pro reader package
  • Sensor Duration: 10 days 
  • Transmitter Range: 20 ft 
  • Calibration: not required 
  • Waterproof (up to 8 ft): 24 h
  • Warm-up Time: 2 hours 
  • Overall MARD: 11.0% 
  • Device Compatibility: multiple Apple iOS and Android devices 

CGM devices have significantly improved diabetes management, offering individuals continuous and accurate real-time tracking of blood glucose levels. With various available options, users can choose the device that best suits their needs, ensuring effective condition management. As technology advances, these devices hold promise in enhancing the quality of life for those with diabetes. 

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