The top features of continuous glucose monitors explained

Variations include: 

• Sensor wear time 
• Approved insertion sites e.g. arms or abdomen 
• Transmitters that are separate and need to be re-used or recharged or included as part of the sensor system 
• Level of water resistance 

Currently, the NDSS subsidy is only available for people living with Type 1 diabetes.  

Speak with your diabetes educator to find out which system might best suit you and your needs and to register you for the NDSS subsidy if you are eligible. 

Here are three key pieces of information that a CGM can provide. 

Where are you now? 

On the home screen of your CGM smart phone App or receiver you will see a glucose reading and colour. This tells you what your glucose level is now. Remember there is a slight delay compared to blood glucose (finger prick) as the sensor uses interstitial fluid to measure glucose levels.  

The colours use a type of traffic light system which is designed so you can quickly see if you are above, below or within your personalised target range. Target ranges can be adjusted in the app settings.  

This number will be updated every 1 to 5 minutes depending on the brand.  

Where are you going? 

Trend arrows show you the direction your glucose is heading and how quickly it is changing. This can be especially helpful in predicting and preventing hypoglycaemia (low glucose levels) if you are at risk.  

Each brand of CGM available in Australia uses slightly different trend arrows but the below table provides a general example.  
 

	Glucose is rising rapidly  (more than 0.1 mmol/L per minute)    Meaning could be 5mmol/L higher in 30 minutes
	Glucose is rising  (between 0.06 and 0.1 mmol/L per minute)
	Glucose is changing slowly  (less than 0.06 mmol/L per minute)
	Glucose is falling  (between 0.06 and 0.1 mmol/L  per minute)
	Glucose is falling rapidly  (more than 0.1 mmol/L per minute)     Meaning could be 5mmol/L lower in 30 minutes

The following is an example of how trend arrows could inform your treatment decisions. 

It is recommended that check your glucose level before you drive to to reduce your risk of having a hypo (less than 4mmol/L) while driving. It is recommended to have a glucose level of at least 5 mmol/L before and while driving. A finger prick test would only show your current blood glucose level, for example 5mmol/L.

In this case you would not make any treatment decision and go ahead and drive. However, if you were using a CGM and saw that your current reading was 5 mmol/L with a downward trend arrow, this indicates that your level could drop to 3 mmol/L or lower within 20 minutes!

In this situation, you could follow your hypoglycaemia treatment plan to prevent a low blood glucose level occurring before getting in the car.  

Speak to your healthcare team for individualised advise on making treatment decisions using trend arrows.  

Where have you been?  

You will also be able to see a graph on the home screen of your CGM reader. This shows your glucose data from the past several hours.  

The shaded grey ribbon in the below example is your customisable target range, so you can see how much time you have spent in target during this time.  

This information can help you to see glucose patterns. For example, if you notice that the majority of the time your glucose levels are above target, this could prompt you to see your diabetes health professional for review.  

If you are not currently eligible for the NDSS subsidy, you may choose to pay full price and use a CGM on occasion, for example before you see your diabetes health professional to assist with a comprehensive review.   

Understanding and effectively using Continuous Glucose Monitors (CGMs) can greatly enhance diabetes management. By providing real-time glucose readings, trend arrows, and valuable insights into glucose patterns, CGMs empower individuals to make informed decisions about their health.