How reliable is the HbA1c .Not very it seems

Susiespearish

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90 day average.jpg
spikes 20's.jpg
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These are my average blood reading as shown.At no point since diagnosis months ago have I been in single figures for more than one reading and yet my HbA1c was showing as 8.4!! This last time it is 14% Hardly very accurate and yes I did get my meter checked .We all put so much faith on this ,especially Type 2's who don't monitor and may go three or even six months between blood tests !

Using our own converter here it's way out http://www.diabetes.co.uk/hba1c-to-blood-sugar-level-converter.html
 

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alaska

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Is there a chance that your HbA1c result may have been 84 mmol/mol -rather than 8.4% ?

If it was 84 mmol/mol, this would be equivalent to an HbA1c of 9.8% and would give roughly average readings of 13.1 mmol/l on your meter.

Given the very high averages you're getting on your meter, I think it's well worth double checking with your health team.

Best wishes
Ed
 
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Susiespearish

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Is there a chance that your HbA1c result may have been 84 mmol/mol -rather than 8.4% ?

If it was 84 mmol/mol, this would be equivalent to an HbA1c of 9.8% and would give roughly average readings of 13.1 mmol/l on your meter.

Given the very high averages you're getting on your meter, I think it's well worth double checking with your health team.

Best wishes
Ed

Nope Alaska it was 8.6 .They always give it in percentage and I asked .I spoke to my GP about the difference as I always take my monitor on appointments .He was as puzzled as me but suggested we check my monitor which we did .He then said "oh well it will catch up eventually " which it has this week but it's taken months ! What if i was totally reliant on that test for an accurate reflection of my BG .It's really quite scary how out it was .
 
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I don't know how often you check and when you check so I can't get a sense of whether your averages above are all from readings taken at times when you are high or not.

What I can say is that there is no correlation between Hba1c and an average of a lot of separate readings. The Hba1c is like a continuous reading that never turns off and averages out the amount of glucose in your blood for some weeks. Instantaneous readings done periodically with a meter and then averaged is bound to give a different result in just about all cases.
 
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AndBreathe

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My only comment would be that however often we might use the finger prick tests, we can't see the whole picture. Only a CGM or potentially the new Abbott Libre will do that. Interestingly, on the Libre thread, where users are giving their feedback, since launch, quite a number are learning of either unexpected highs, and often unexpected very low, lows overnight. One guy even commented about rice spiking him 5 hours after eating it!!

Unfortunately, for now, these appear to be the best tools we have.
 
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Susiespearish

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I don't know how often you check and when you check so I can't get a sense of whether your averages above are all from readings taken at times when you are high or not.

What I can say is that there is no correlation between Hba1c and an average of a lot of separate readings. The Hba1c is like a continuous reading that never turns off and averages out the amount of glucose in your blood for some weeks. Instantaneous readings done periodically with a meter and then averaged is bound to give a different result in just about all cases.

I do understand what your saying but can't understand how that can be right ??I'm more than happy if as you say they averaged at far lower continuously .I test usually between once and twice a day but I could grab my meter at any time of the day and the reading would not be in single figures so I'm puzzled how my bloods were so low .They now reflect my meter readings at 14% but the last two readings didn't .
 

Susiespearish

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My only comment would be that however often we might use the finger prick tests, we can't see the whole picture. Only a CGM or potentially the new Abbott Libre will do that. Interestingly, on the Libre thread, where users are giving their feedback, since launch, quite a number are learning of either unexpected highs, and often unexpected very low, lows overnight. One guy even commented about rice spiking him 5 hours after eating it!!

Unfortunately, for now, these appear to be the best tools we have.

Well Squire Fulwood has gone some way to explaining the discrepancy and let's hope he's right because clearly no one wants to be at those BG's permanently but I can only go by my meter :)
 
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There is another possible fiddle factor here. A long time ago I got involved in testing meters against known control solutions. Only one was accurate in the low ranges and the other three were high. In the high ranges all meters read high and the SD codefree went into orbit. It measured a 16.7 control solution as 24.3 (from memory). These facts are not cheering when your health depends on it.

I know nothing about the meter you are using.
 
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SirAndy

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Those readings are very high.I hope with the right medication you can get them down.
As mentioned the HBa1c gives an average over several months so if you have those readings a few times but at other times they are reasonable your average would be decent. It is a worry though after pricking to see a high number.
My diabetic nurse said the meters are always out by a few numbers so you could actually be lower than what is shown.


Sent from the Diabetes Forum App
 
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Susiespearish

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There is another possible fiddle factor here. A long time ago I got involved in testing meters against known control solutions. Only one was accurate in the low ranges and the other three were high. In the high ranges all meters read high and the SD codefree went into orbit. It measured and 16.7 control solution as 24.3 (from memory). These facts are not cheering when your health depends on it.

I know nothing about the meter you are using.

It's a Spirit CareSens N Squire Fulwood and we checked it against the practice nurses meter and another because that was my first thought that the meter was faulty . If it means my BG isn't as high as it's showing I can live with that but not great for tapering my meds and diet too !! :)
 

Susiespearish

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Those readings are very high.I hope with the right medication you can get them down.
As mentioned the HBa1c gives an average over several months so if you have those readings a few times but at other times they are reasonable your average would be decent. It is a worry though after pricking to see a high number.
My diabetic nurse said the meters are always out by a few numbers so you could actually be lower than what is shown.


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Those are average readings for 7/30 and 90 days SirAndy .I frequently spike in the 20's as shown :-(
 
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It's a Spirit CareSens N Squire Fulwood and we checked it against the practice nurses meter and another because that was my first thought that the meter was faulty . If it means my BG isn't as high as it's showing I can live with that but not great for tapering my meds and diet too !! :)

I still know nothing about your meter but there is one ray of hope. If you are a T2 with a high reading meter then having high blood sugar means fewer problems than the alternative. By this I mean that if you had low blood sugar then such a meter might be telling you that you haven't.
 

SirAndy

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My goodness. They really need to be taking a look at your medication if that's the case. Are you on insulin?

I had an appointment at the hospital last week and was prescribed insulin but told to take it only if I'm clocking readings of 10.0+ consistently
for a period of time.


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Susiespearish

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I still know nothing about your meter but there is one ray of hope. If you are a T2 with a high reading meter then having high blood sugar means fewer problems than the alternative. By this I mean that if you had low blood sugar then such a meter might be telling you that you haven't.

Oh yes !! That would be very dangerous wouldn't it .Will I be able to rely on this meter when i go on insulin at the end of the month though ??
 

Susiespearish

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My goodness. They really need to be taking a look at your medication if that's the case. Are you on insulin?

I had an appointment at the hospital last week and was prescribed insulin but told to take it only if I'm clocking readings of 10.0+ consistently
for a period of time.


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My endocrinologist seems to suspect I have an adrenal tumour after tests .He wanted me to start insulin but I wanted to give a new med a try this month first.I do have other health problems such as hypertensive cardiomyopathy so these may be playing a part .I don't know .I'm just trying to lose more weight to help it all out .
 
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My only view on this is that if the Hba1c wasn't reliable then why would they do it!? There's much more to it than just pricking your finger at certain times as you don't know what your sugars are all the time!
 

SirAndy

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It's quite possible that the existing conditions may be contributing to the high reading.
Make sure your diabetic nurse and GP run all possible tests to determine.
Losing weight should also help I think.


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Oh yes !! That would be very dangerous wouldn't it .Will I be able to rely on this meter when i go on insulin at the end of the month though ??
I would try to get my hands on another one. I don't think you are confident in this one and you need to compare, learn what's going on and find something that you trust.
 
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