1. What is Continuous Glucose Monitoring (CGM)?

Continuous glucose monitoring (CGM) systems use a glucose sensor (contained in a small needle) to measure the level of glucose in the fluid under the skin. The sensor is attached to the skin with a sticky patch, and it wirelessly transmits results to a small recording device (about the size of a cellphone). You can attach the recording device to your clothing, carry in a purse or bag, or place it near you (eg, on a bedside table). The monitor updates and displays your blood sugar level every few minutes.

You must remove the sensor and replace it on a different part of your body approximately once per week. Because of reliability issues and the need to calibrate the devices, CGM does not eliminate the need for at least occasional fingersticks.

2. Who might need CGM Test ?

Patient selection is a key factor for the successful use of CGM. CGMs are most often used by people with type 1 diabetes who give themselves multiple daily insulin injections or use an insulin pump. Devices that combine an insulin pump with a CGM system are also available .Many experts think that CGM may be most useful in people who have frequent episodes of low blood sugar, episodes of low blood sugar during the night ("nocturnal hypoglycemia"), and/or difficulty recognizing when they have low blood sugar.

Intermittent use of CGM may also be appropriate for selected people with type 2 diabetes treated with multiple daily insulin injections, particularly those with frequent episodes of low blood sugar or difficulty recognizing when they have low blood sugar.

3. What are advantages of CGM Test?

 There is evidence that people with type 1 diabetes who use a CGM system consistently and reliably (rather than the finger prick method) have modestly better-controlled blood sugar.

The CGM displays your blood sugar level every few minutes, allowing you to see if the level is increasing, decreasing, or stable. The receiver can also be set to trigger an alarm if your blood sugar level is above or below a preset level, which can be especially helpful for people who cannot feel when they have low blood glucose (also known as "hypoglycemia unawareness").

You can download blood sugar results from the CGM to your computer or smart phone, allowing you to see blood sugar trends over time. Your doctor can help you figure out how to use this information to determine if you need to adjust your insulin dose.

4. Are there any drawbacks of CGM Test?

Although the accuracy of CGM is improving, CGM does not eliminate the need for at least occasional finger pricks to calibrate the monitor and to verify that the sensor readings are accurate.

In addition, the costs associated with CGMs are much greater than those of traditional glucose monitors. Not all continuous glucose meters and supplies are covered by commercial health insurance companies.