HbA1c Explained

What is HbA1c?

HbA1c is known as glycated haemoglobin and is made when the glucose cells in your body stick to red blood cells. When your body cannot control the amount of glucose, more of it will stick to the red blood cells and can cause a build-up. Having a high HbA1c number will mean that you have too much glucose in the blood.

HbA1c is the average blood glucose level from the last 2-3months, as that is how long it takes for the red blood cells in the body to renew. It is a figure written as mmol/mol but can also be given as a percentage (%).

How do you test HbA1c?

Testing is usually carried out by a healthcare professional and involves a blood test. You are able to pay for a test in which you can use a finger prick test to give you a snapshot of where your blood glucose levels are, but these cost and the GP can schedule a test for free.

How often should I be tested?

Your HbA1c levels should be tested every 3-6 months, until the levels have stabilised, and you are on a steady medication. It should move to being tested every 6 months to a year once that HbA1c levels are stable. It is important not to skip these tests.

What should my target be?

Keeping your HbA1c levels as close to normal as possible is important when managing diabetes. Your diabetes team should explain your target to you as it may need to be more personal. There are three main targets that are used for different groups:

• HbA1c level of 48mmol/ml (6.5%) – this target is usually for adults whose type 2 diabetes is managed either by lifestyle or diet, or combined with a single drug which is not associated with hypoglycaemia.
• 53mmol/mol (7.0%) – this target is for adults on a drug associated with hypoglycaemia
• Relaxed HbA1c target – this may be appropriate in adults with type 2 diabetes who are older, frail, with an impaired awareness of hypoglycaemia, or if they drive or operate machinery as part of their job.

Be aware there are some reasons why your HbA1c levels may change:

• Changes in your lifestyle – diet, exercise, smoking etc
• If you are not feeling well
• Taking other medication such as steroids
• Feeling stressed or depressed

Speak to your healthcare professional if you are concerned about your HbA1c levels or haven’t had your test recently.

References:

Diabetes UK (No date) What is HbA1c? Available at: https://www.diabetes.org.uk/guide-to- diabetes/managing-your-diabetes/hba1c (Accessed on 5 April 2023).

NICE (2022) Type 2 diabetes in adults: management. Available at:
https://www.nice.org.uk/guidance/ng28/chapter/Recommendations (Accessed on 5 April 2023).