Hba1c and my glucose monitor

[Sharron1]

I am due my hba1c blood test in a few weeks and also regularly keep an eye on my eating by finger pricking. I have checked the memory for 3 months worth and it gave me an average of 6.

While I think the blood test looks at other things as well, I did wonder if I could hazard a rough estimate of my hba1c? I think I recall someone saying the actual blood test result is slightly higher than the the monitor.

 

[RBZ5416]

HbA1c Estimator

 

[Sharron1]

Thank you. A pleasing 35 and in a few weeks I will see what the Hba1c result is.

 

[RBZ5416]

But bear in mind that HbA1c is an average of 24/7 over some 90 days & your finger pricks are just snapshots of a moment in time.

 

[everydayupsanddowns]

One of the challenges is that fingerstick monitors and HbA1c measure completely different things.

One measures a spot-check moment in time, and the other reflects changes to red blood cells caused by circulating glucose 24 hours a day for 3-4 months.

So there isn’t a mathematical conversion between average fingerstick levels and HbA1c, partly because it would depend on when you took the fingerstick checks, and how effectively those results reflected your overall glucose levels.

There are various empirical formulae which have been developed from a ‘best fit’ between known pairs of average fingerstick glucose, and matched HbA1c, but they only ever give a vague guess.

If you are interested, one goes like this:

HbA1c (in % units) = (AvgBG+2.52)/1.583

then you’d need to convert to mmol/mol with

HbA1c in mmol/mol = (HbA1c%-2.15) x 10.929

Hope that helps!

 

[Sussexmax]

Thank you. A pleasing 35 and in a few weeks I will see what the Hba1c result is.

Fingers crossed that sort of result will be replicated! Is that what you expect/are hoping for? You’ve been incredibly consistent with your scores!

 

[grovesy]

I am one of those whose blood test is actually high, I also find the same with my Libre predication.

 

[Sharron1]

One of the challenges is that fingerstick monitors and HbA1c measure completely different things.

One measures a spot-check moment in time, and the other reflects changes to red blood cells caused by circulating glucose 24 hours a day for 3-4 months.

So there isn’t a mathematical conversion between average fingerstick levels and HbA1c, partly because it would depend on when you took the fingerstick checks, and how effectively those results reflected your overall glucose levels.

There are various empirical formulae which have been developed from a ‘best fit’ between known pairs of average fingerstick glucose, and matched HbA1c, but they only ever give a vague guess.

If you are interested, one goes like this:

HbA1c (in % units) = (AvgBG+2.52)/1.583

then you’d need to convert to mmol/mol with

HbA1c in mmol/mol = (HbA1c%-2.15) x 10.929

Hope that helps!

I can feel my brain spinning Best for me to wait until actual result of Hba1c. Can't second guess the system. Am more interested in the cholestrol result, after 4 months.

 

[Docb]

Hi @Sharron1 - you must know I like the number games.......

There is a good chance that a 6 mmol/l finger prick average will give you an Hba1c under 40.

That's about the best you can do unless you are a complete nerd, a dab hand at stats and spreadsheets and derive pleasure (some do you know) from using large data sets to chase rainbows.

I predicted my last two HbA1c's to within +/- 1 mmol/mol which must make me a rainbow chasing nerd with a couple of technical skills.

 

[Sharron1]

Fingers crossed that sort of result will be replicated! Is that what you expect/are hoping for? You’ve been incredibly consistent with your scores!

Time will tell...

 

[Sharron1]

Hi @Sharron1 - you must know I like the number games.......

There is a good chance that a 6 mmol/l finger prick average will give you an Hba1c under 40.

That's about the best you can do unless you are a complete nerd, a dab hand at stats and spreadsheets and derive pleasure (some do you know) from using large data sets to chase rainbows.

I predicted my last two HbA1c's to within +/- 1 mmol/mol which must make me a rainbow chasing nerd with a couple of technical skills.

Hmmm. Numbers and number crunching not really my thing. Think I will wait for my HbA1c result.

 

[Docb]

Hmmm. Numbers and number crunching not really my thing. Think I will wait for my HbA1c result.

That's what I call a good idea!

 

[trophywench]

Whatever my meter and Libre has predicted I've been surprised whenever the actual result hasn't been pretty normal for me in the low 50s. The last 2 have been over 60 and No Way Pedro am I happy about that. They're going to retest my 'Full Blood Count' at the end of Feb since clinic Dr said my white cell count was elevated and letter said they'd send me a blood test form, which I now have and that mentions lymphocytes. I've been googling some of which might be a bit scary however some of it did mention a couple of things which rang very true, not least of those - smoking affecting the efficiency of bone marrow reproducing new red blood cells - but that apparently stays affected even if you pack it in successfully anyway. That's caused by inhaling benzene (apparently, which eg petrol fumes also contain and nobody enjoys them whether you smoke or not - so surely everyone on earth including me tries to get away from having to breath them in asap and only puts up with them as a necessary evil when actually filling their tank?)
I have wondered recently - they used to say the standard HbA1c test was unreliable if the person had anaemia - so, could that apply in my case? No idea ! A couple of times they've reported my folates being low in the winter months so have prescribed 5mg folic acid tablets for a month or two, but not this time.
I'll just have to wait & see.

 

[Lucyr]

They're going to retest my 'Full Blood Count' at the end of Feb since clinic Dr said my white cell count was elevated and letter said they'd send me a blood test form, which I now have and that mentions lymphocytes. I've been googling some of which might be a bit scary

I wouldn’t panic about high white blood counts unless you’re given a specific reason to panic. Mine has been high for at least 2 years, and was being tested regularly throughout that time. It’s just been decided now that my normal is an outlier.

 

[trophywench]

What has raised my concern is the fact that the D Clinic doctor referred my lab results to the on-call haematologist, and he said to check it again and request that a blood film be made with that blood and that the blood film be checked by a doctor - presumably that will be a haematologist that would need to look at the slide, though that isn't specified on said blood test form. Unless the chap I saw, who wasn't the actual consultant himself, has a special extra interest in blood diseases or summat entirely different. In the letter the D chap said he'd tried to ring me before he wrote. I saw him at the end of November and letter is dated 9th January. Odd I couldn't find any 'missed calls' recorded on my phone that I hadn't dealt with then .......

I'd already concluded I'll just have to wait and see.