Continuous glucose monitoring may either be retrospective for diagnostic purposes or it may be used in real-time.

Diagnostic continuous glucose monitoring systems are blinded to the individual who is wearing it. It is used by the healthcare professional to:

• Detect asymptomatic or nocturnal hypoglycaemia, and
• Aid in titration of medications, insulin doses or nutritional adjustments.

Real-time continuous glucose monitoring also contains alarms which can alert the user if the glucose level is rising or going below a pre-set threshold. This will allow the user to make changes to prevent or correct a high or low glucose level.

Most real-time continuous glucose monitoring requires once to twice daily blood glucose calibrations (involving fingerprick glucose tests) and each sensor lasts for up to 6 days.

"Real-time continuous glucose monitoring has been shown to improve overall glucose control in terms of improvements in HbA1c and reduction of the frequency of hypoglycaemia, particularly in those with type 1 diabetes," says Dr Daphne Su-Lyn Gardner, Consultant from the Department of Endocrinology, Singapore General Hospital (SGH), a member of the SingHealth group.

However, real-time continuous glucose monitoring needs to be used regularly for this improvement to be effected.

In addition, real-time continuous glucose monitoring may be combined with insulin pump therapy to allow for automated insulin suspension in response to, or prior to, a pre-set low glucose level. It may also be used in the future to control the high glucose levels by automatically controlling delivery of basal insulin.

Ref: O17