Type 1 Freestyle Libre

[MNO]

I have recently started using the freestyle libre glucose monitor instead of the blood testing kit AgaMatrix. I have had several occasions where I have questioned the result of the libre monitor and so compared the result to a blood test. I have not calibrated my testing kit for months but there is a large difference in result e.g. libre stated 2.9 and blood test kit was 8.8. I didn't feel low at the time but wasn't sure what my glucose was or whether to have sugar or not. Please advise on which I should be using or both, and why the results are so different.

Thanks

 

[urbanracer]

Hi @MNO and welcome to the forums.

Take a look at this thread....
https://www.diabetes.co.uk/forum/threads/accuracy-of-freestyle-libre.136494/

I think you will find it informative.

 

[EllieM]

Yes, freestyle libre doesn't work for everyone. If in doubt, believe the meter. To summarise
1) freestyle is meant to match the blood sugar reading 15 minutes before the libre reading.
2) many people find the first 24 hours are very inaccurate.
3) some people find the last couple of days very inaccurate
4) some sensors are dud.
5) if you record the sensor readings against blood sugar readings for a couple of days (remember the 15 minute delay) and get serious discrepancies, you can phone Abbott and they'll probably replace the sensor for free.
6) a few people (eg me after 8 months of good results) find they don't get decent results whatever they do, but I'd get a replacement sensor from Abbott before you assume that, as for most/many people it works very well.

Good luck.

 

[noyahO21]

I'm very disappointed with the Freestyle Libre sensors and have stopped using them. I've had Type 1 diabetes for 52 years since age 3. Having the Libre sensor was such a relief and so convenient after checking bsl for so many years. I found it particularly helpful during the night. I used the Freestyle Libre for almost a year before I discovered that it was completely inaccurate. My HbA1c gradually rose from 6.7 to 6.9 and then 7.5% before I realised something wasn't right as the Libre results didn't match the rise in my HbA1c. My Endocrinologist advised me to do one month of paired testing, i.e. used both the Libre sensor and did bsl checking together. The results clearing showed that the Libre sensor consistently read anywhere between 2 to 5 mmol lower than my bsl result - hence the reason my HbA1c rose.
My daughter, 20, who was diagnosed with Type 1 diabetes just over a year ago, has also stopped using the Libre sensors after experiencing the same. I'm hoping one day it'll be more accurate.
I'd be happy to hear from anyone who's experienced such discrepancies using the Libre sensors.

 

[novorapidboi26]

@helensaramay does the glimp app work without a third party device.....or are you using it purely as a recording tool....and if so, how do you calibrate...?

 

[Muneeb]

@helensaramay does the glimp app work without a third party device.....or are you using it purely as a recording tool....and if so, how do you calibrate...?

I second helensaramay. Glimp is far superior for me, can use as normal with NFC or with miaomiao as a CGM. Can calibrate with meter and get much better accuracy. Can also use the app with data on any number of devices, I also have it on my smartwatch.

 

[Muneeb]

I'm very disappointed with the Freestyle Libre sensors and have stopped using them. I've had Type 1 diabetes for 52 years since age 3. Having the Libre sensor was such a relief and so convenient after checking bsl for so many years. I found it particularly helpful during the night. I used the Freestyle Libre for almost a year before I discovered that it was completely inaccurate. My HbA1c gradually rose from 6.7 to 6.9 and then 7.5% before I realised something wasn't right as the Libre results didn't match the rise in my HbA1c. My Endocrinologist advised me to do one month of paired testing, i.e. used both the Libre sensor and did bsl checking together. The results clearing showed that the Libre sensor consistently read anywhere between 2 to 5 mmol lower than my bsl result - hence the reason my HbA1c rose.
My daughter, 20, who was diagnosed with Type 1 diabetes just over a year ago, has also stopped using the Libre sensors after experiencing the same. I'm hoping one day it'll be more accurate.
I'd be happy to hear from anyone who's experienced such discrepancies using the Libre sensors.

I found this and you have to be careful, as I was too reliant upon it initially which almost led me to hypo unawareness. As helensaramay stated, I use GLIMP app and its much better.

 

[Muneeb]

@helensaramay does the glimp app work without a third party device.....or are you using it purely as a recording tool....and if so, how do you calibrate...?

Just one thing to add, GLIMP is only for android devices, spike is for apple. Xdrip is a Glimp alternative for android which some people prefer.

 

[novorapidboi26]

So how do you calibrate with Glimp....?

Define calibrate..

 

[Muneeb]

So how do you calibrate with Glimp....?

Define calibrate..

Well its basically a fudge factor applied to a pre-set correlation that adjusts that correlation to fit what the meter is reading.

In glimp you take a reading from meter and add it into the glucose reading section...

 

[novorapidboi26]

Is that not just adding in a blood test reading.....does the app use that alongside the sensor reading......

I confess I haven't played about with it.....I will tonight though...

 

[Muneeb]

Is that not just adding in a blood test reading.....does the app use that alongside the sensor reading......

I confess I haven't played about with it.....I will tonight though...

You add the monitor reading, if its too far from the sensor reading in the app it will calibrate automatically. You don't have to do anything apart from put the readings in.

 

[Scott-C]

Is that not just adding in a blood test reading.....does the app use that alongside the sensor reading......

I confess I haven't played about with it.....I will tonight though...

The sensor generates a raw number based on how much glucose there is and then turns it into what it thinks is a bg number. But it can get it wrong.

So, if you wait until your levels are fairly stable, there's a fair chance that bg and ifg will be about the same, so if, say, the sensor is reading it as 3.6 but a bg test shows it's 4.7, you type in the bg reading as a calibration to tell it, nah, it's not 3.6, it's 4.7, so the sensor will be more accurate in how it interprets the raw numbers it gets.

 

[novorapidboi26]

Thanks folks.......I on the same page now.....