How does your meter read?
With millimoles ,
And clinical accuracy?
Mary Mary quite contrary
What does you meter mean?
Glucose in blood whole?
Or from the plasma sole
It's average your A1c?
With Apologies to Northerner: imitation is the sincerest form of flattery! (I don’t think it scans as well as your poems)
Any PWD on the internet soon realises that different parts of the world use different measurements for blood glucose readings. In the US, some parts of Europe and the Middle East they use milligrams per decilitre. In the UK , some parts of Europe and many places that are English speaking (Canada, Australia etc) they use millilmole per litre. To be awkward in France they use grams per litre.
It’s easy to change between the two, there are many convertors on the web but all you have to do to convert mmol to mg/dl is to multiply by 18, if you want to convert mg/dl to mmol/l you divide by 18. After a while you become bilingual.
But there is another difference that isn’t so obvious. When we measure our glucose we use whole blood from a capilliary. When a laboratory measures blood they measure the levels in the plasma.
For many years all the blood glucose meters reported the glucose level as in whole blood but this was not the same as a laboratory measurement would be. A laboratory plasma measurement would be about 12% higher than a whole blood one. In recent years some manufacturers have included a calculation (done automatically) that works out what the plasma reading would be and displays that as its reading.
If it were plasma calibrated and it read 72mg/dl, the whole blood meter would read 64.3mg/dl.
So what constitutes a hypo depends upon what meter you are using.
In the US all modern meters give plasma readings but in Europe some give plasma and some whole blood, and it’s not always easy to find out which does what. If you want to find out you may have to search.The place I found mine was not with the meter instructions but in very tiny print in the leaflet that comes with the testing strips.
This chart shows equivalents in mg/dl and mmol for both whole blood and plasma calibrated meters.
Of course even when you know what the meter reads, it’s not necessarily very accurate. They are allowed to be up to 20% out,. There is a convertor on the Lifescan website which demonstrates this clearly.So with that reading (4mmol) you could either be quite hypo and need some glucose quickly , just at a ‘safe’ level or have a very normal blood glucose reading!
And if you find that your HbA1c doesn’t really reflect what your meter has been telling you, perhaps this built in inaccuracy is a possible reason.