Continuous Glucose Monitoring (CGM)

CGM has proven to be the best outpatient glycemic management system for reducing A1C. People with type 1 diabetes have experienced an average A1C reduction of 1.3%1


What is a Continuous Glucose Monitor (CGM)?

A CGM measures glucose levels every 1-5 minutes and gives information on glucose trends with arrows. This information gives a bigger picture of where the blood sugar is going and helps inform diabetes decisions. Access to the CGM data has been shown to improve health outcomes and has led to the change in goals for people with diabetes to be time in range rather than HbA1c.1 CGM use is recommended by the American Diabetes Association for anyone with type 1 diabetes and those with other diabetes types using Multiple Daily Injections (MDI).1

It's important to note that CGMs are reading interstitial fluid (the fluid under the skin) versus blood glucose. The levels are closely related but not the same. Usually, the sensor glucose levels are about 5-10 minutes behind the blood glucose values.2 This means they do not typically read the same number, but it does not necessarily mean the sensor is not accurate. It varies more when glucose levels are rapidly changing and if there are any interactions in the body (see chart for interactions with specific CGMs).

A CGM System consists of three basic parts:

  1. Sensor—A small sensor, typically a wire, is inserted just beneath the skin. The process is similar to infusion sets for insulin pumps. A sensor is typically approved to be worn for up to 7-14 days.
  2. Transmitter—A small wearable that is attached to the top of the sensor and sends glucose data wirelessly to your compatible smart device or receiver. Some are disposable, whereas others are reusable and need to be removed after use and replaced with the next sensor. Most newer sensors have transmitters that are already attached to the sensor and are disposable.
  3. Receiver—A compatible smart device, insulin pump, or receiver will have a display screen to see your current glucose number and review past and present glucose trends.

Benefits of a CGM

  • HbA1c Reduction:  CGM has proven to be one of the best outpatient glycemic management systems for reducing HbA1C.1
  • Reduced Hypoglycemia: Many studies have shown that CGM decreases time spent in hypoglycemia.
  • Alerts and Alarms: CGM Systems are equipped with alerts and alarms that notify you of approaching highs and lows, helping you increase your time in range.
  • Real-time glucose information:  Your CGM provides real-time information about your glucose level, speed, and direction (high or low) so you can have more insight into proactively managing your diabetes.
  • Remote Access to Data: Many systems allow you to share glucose data with family, friends, and even your healthcare team. This allows you to have a better safety net and gives your medical team a greater ability to help you achieve your diabetes management goals.

CGM Options in the U.S. 2024

CGM Options in 2024

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