I am T2D and recently started to use a Freestyle "Libre" to monitor my BG levels. I was surprised at a recent review with my diabetic nurse to have recorded an HbA1c of 56% when my "Libre" was predicting 44% and I had been following a low-carb diet. So I then started to cross-check the "Libre" with a finger-prick BG monitor. The monitor invariably read between 5 and 12% higher than the "Libre". So today I have done a three-way check: the "Libre" showed 5.9: finger-prick 1, 6.9: and finger-prick 2, 7.8. I love the convenience of the "Libre" but as a "self-funder" am minded to return to the finger-pricker. But before doing so, which device would you recommend that I believe in?
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Which device do I believe
- Thread starter Mike97
- Start Date
Mbaker
Well-Known Member
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- 4,340
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- Type of diabetes
- Treatment type
- Diet only
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- Available fast foods in Supermarkets
I have had a similar issue, except that I have tested with circa 5 or 6 finger prick devices between all waking hours and always have great numbers I.e. fbg between 3.8 and 4.4 (at least 98% of the time) with an occasional 4.6 if I haven't slept due to work. Post prandial always under 6. On 2 units the fbg was the same as my Doctors surgery, which were synchronised so therefore accurate.
The Libre always reads lower and predicts HbA1c's of 22, with the finger prickers around 31 and multiple A1CNow+ tests showing a 30 - 31.
At my local hospital I have a HbA1c of 39 and a private Medichecks test was 39....except on another Medichecks assay (the type recommended for unusual cases) I get a 35.5. It is clear to me that for some other factors come into play.
What is important is base lining with whatever device and watching the variance e.g on an Accu - Chek I had a fbg this morning of 4.1 which I am happy with.
The Libre always reads lower and predicts HbA1c's of 22, with the finger prickers around 31 and multiple A1CNow+ tests showing a 30 - 31.
At my local hospital I have a HbA1c of 39 and a private Medichecks test was 39....except on another Medichecks assay (the type recommended for unusual cases) I get a 35.5. It is clear to me that for some other factors come into play.
What is important is base lining with whatever device and watching the variance e.g on an Accu - Chek I had a fbg this morning of 4.1 which I am happy with.
- Messages
- 4,398
- Location
- Suffolk, UK
- Type of diabetes
- Type 2
- Treatment type
- Tablets (oral)
- Dislikes
- Diet drinks - the artificial sweeteners taste vile.
Having to forswear foods I have loved all my life.
Trying to find low carb meals when eating out.
Firstly, remember that the Libre measures interstitial fluid, not blood.
So the reading is usually 15-20 minutes behind the finger prick test, and to cross check you take a finger prick, wait 20 minutes, read the Libre.
Secondly, in my experience each Libre is different and is not consistent from first application to when it finally quits two weeks later. Some read high, most read slightly low, in my experience only.
Bottom line is that if you want an accurate BG reading you use a finger prick.
If, however, you want to find out what is happening between finger pricks and especially overnight, then the Libre is brilliant for showing trends. In my opinion it is worth the money just to find stuff out.
If you have a suitable NFC Android phone you can use the 3rd party App Glimp, which allows you to calibrate your sensor against finger prick tests and can be more accurate.
I use LibreLink on an Android phone, and it always predicts a better HbA1c than I get in tests. So you should not rely on the Libre to give you an accurate BG reading nor an accurate HbA1c . Your call how often you use one to learn about what your body does between finger pricks,
xfieldok
Well-Known Member
My freestyle currently estimates my hba1c is 33. However my last hba1c in December was 50, up from 44 in October.
The freestyle is notoriously inaccurate below 4, my readings in the morning are usually in the 3s, a fingerprick usually tells me in the 4s.
I am a bit more complicated because of steroids, once I have been weaned off them,I will be happy to go back to my Tee2 and mySugr app.
The freestyle is notoriously inaccurate below 4, my readings in the morning are usually in the 3s, a fingerprick usually tells me in the 4s.
I am a bit more complicated because of steroids, once I have been weaned off them,I will be happy to go back to my Tee2 and mySugr app.
