Correction factors (or insulin sensitivity) are an important tool in helping to manage the blood glucose level. One of the major benefits of regularly checking glucose levels is the ability to ‘correct down’ unexpected high readings at meal times. However if corrections appear to be the norm at particular times of day, it is worth considering what factors are contributing to the persistently high glucose readings and addressing them, rather than relying on corrections.
Constant corrections can make it difficult to pick out underlying patterns and sometimes it can be useful to stop correcting for a spell to help work out what is causing the underlying problem. Correction factors, like insulin: carbohydrate ratios, differ between individuals and can also be different at different times of day. Aiming to correct down to a glucose of 7 mmol/L is typical.
What is my correction factor?
A simple way to estimate your correction is:
Correction factor = 100 / (total daily insulin dose)
So in someone taking roughly 25 units of novorapid and 25 units of levemir (total insulin = 50 units):
Correction factor would be 100 / 50 = 2 This means 1 unit would be expected to drop the blood glucose by 2 mmol/L.
If at lunch time their blood glucose was 13 they would take 3 extra units on top of their calculated dose (those 3 units would be expected to drop the glucose by 6, therefore getting them to their target glucose of 7).
If correction factors start to become associated with subsequent hypos, then they should be increased (e.g. from 1 unit lowering 2 mmo/L to 1 unit lowering 2.5 mmol/L). If they do not seem to be getting the glucose down to target, they may need decreased (e.g. down to 1 unit lowering 1.5 mmol/L glucose).