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Freestyle Libre reading low

H

hels

Well-Known Member
Messages
312
Location
Bristol, UK
Type of diabetes
Type 1
Treatment type
Insulin
I have recently moved from a Dexcom to a NHS funded Freestyle Libre. I am finding that the Libre consistently reads around 1.5 to 2mmol/l lower than my finger prick readings and what the Dexcom was (I overlapped them a bit). I tend to have pretty good control so this means the Libre often says I am in the 3s so I am reluctant to share my data with the hospital as they will give me hassle or remove my funding for being low when I’m not. Is there anything I can do to calibrate? And what does anyone else do if their Libre consistently reads low?
 
hels said:
I have recently moved from a Dexcom to a NHS funded Freestyle Libre. I am finding that the Libre consistently reads around 1.5 to 2mmol/l lower than my finger prick readings and what the Dexcom was (I overlapped them a bit). I tend to have pretty good control so this means the Libre often says I am in the 3s so I am reluctant to share my data with the hospital as they will give me hassle or remove my funding for being low when I’m not. Is there anything I can do to calibrate? And what does anyone else do if their Libre consistently reads low?
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Hi,

I fund mine, but my team where cheeky enough to want an invite for Libre link? (So I obliged.)
I would at low points make notes on the app "the meter says X." "The meter actually is saying Y." Libres seem to take a while recovering from real hypos. Alway double check the meter.
Of course I had to reverted back to scanning & double book keeping?

I was using the Miaomiao 2 with the XDrip app, which can be calibrated..
Glimp, another pretty good free app also has the feature to calibrate. But I found it less stable on my device with the Bluetooth transmitter.

Hope this helps.
 
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hels said:
I have recently moved from a Dexcom to a NHS funded Freestyle Libre. I am finding that the Libre consistently reads around 1.5 to 2mmol/l lower than my finger prick readings and what the Dexcom was (I overlapped them a bit). I tend to have pretty good control so this means the Libre often says I am in the 3s so I am reluctant to share my data with the hospital as they will give me hassle or remove my funding for being low when I’m not. Is there anything I can do to calibrate? And what does anyone else do if their Libre consistently reads low?
Click to expand...

Hi there, obviously you need to find out if this particular sensor is faulty (is it your first one or do they all read lower than you would expect)? Also don't forget the Libre is a good 15 minutes behind a finger prick test so when you do a finger prick test make sure you check the Libre again 15 minutes later. I do this often and the Libre usually shows a similar reading to the blood prick from 15 minutes before.

Having said that, when a Libre reading reads below 4 I always do the finger prick check using the reader machine, that way anyone looking at it will see the libre was showing 3 for example but a prick test was showing 5. At some point you will HAVE to share your data with the hospital as that is a condition of them funding the libre (I believe). Don't worry too much about that if you have the evidence that you are not constantly low. I get what you mean because my recent telephone consultation with the Consultant was interesting. He tried to go solely on the libre readings and I had to explain that when the libre was showing under 4 it was off by a whole point at least (backed up to a large extent by my finger prick tests). He said 'Oh, do you not eat any carbs on a Wednesday' and I was baffled at the time saying 'Yes, I eat normally like any other day'. Afterwards I checked and realised that it was on a Wednesday that I always changed my sensor meaning for the first 24 hours or so it ALWAYS gave much lower readings! x
 
Thanks all. This is my first Libre and I am a couple days in. When I was using a Dexcom that also usually started off low and was often a bit lower than finger pricking for a while. However when I had the Dexcom it was not NHS funded so I didn't need to share the data. I am pretty confident in managing my blood sugar levels and just don't want to end up battling with the hospital over my readings being too low when they are not and end up losing my funding. Do all the notes get shared via LibreView (my meter is not a Freestyle one so data from that won't be automatically uploaded)? I thought I read somewhere that they don't.

I think I'll wait until I've got at least a few weeks of data before I share my data via LibreView.
 
hels said:
Thanks all. This is my first Libre and I am a couple days in. When I was using a Dexcom that also usually started off low and was often a bit lower than finger pricking for a while. However when I had the Dexcom it was not NHS funded so I didn't need to share the data. I am pretty confident in managing my blood sugar levels and just don't want to end up battling with the hospital over my readings being too low when they are not and end up losing my funding. Do all the notes get shared via LibreView (my meter is not a Freestyle one so data from that won't be automatically uploaded)? I thought I read somewhere that they don't.

I think I'll wait until I've got at least a few weeks of data before I share my data via LibreView.
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Hi,

I was sharing via scanning the sensor on my phone via the Libre link app? But I kept notes on the app along with carbs & dosage plus regarding what my meter said. ;)

The actual data from my meter?
Nurse normally asks "have you got your meter?" To which I reply yes, producing it.
She then proceeds to snatch it like a phone robbery, then fumbles for the right cable to brutally plug it into her into her PC.
 
I really like having the graphs and data available to me to make decisions. I don't usually record my carbs & dosage unless I am trying to sort out a particular issue as I get bored of inputing the data and they don't vary much as I eat very low carb. My consultant retired recently and he was always great - most my appointments consisted of him telling me I was doing well, seeing if I had any concerns, then having a nice chat. He asked me a few questions about how much insulin I was using and what kind of levels I had but never asked to see my meter. But I have had a glimpse of the more militant types when I have seen someone else or at my GPs surgery.
I guess I just feel jumpy about having my data scrutinised and also what else they do with the data - I think I will ask them for their data policy to see if they share with anyone else.
 
hels said:
I guess I just feel jumpy about having my data scrutinised and also what else they do with the data - I think I will ask them for their data policy to see if they share with anyone else.
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To be honest whether you like it or not it may well be one of the things you have to do to get your funding continued with it (as mentioned by @KK123 , I know I had to)

Edit: I know everytime I went for my appointments at the hospital they asked for my meter and libre reader so they could download the results at anyrate, it was just quicker if I shared all the data with them beforehand
 
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hels said:
I really like having the graphs and data available to me to make decisions. I don't usually record my carbs & dosage unless I am trying to sort out a particular issue as I get bored of inputing the data and they don't vary much as I eat very low carb. My consultant retired recently and he was always great - most my appointments consisted of him telling me I was doing well, seeing if I had any concerns, then having a nice chat. He asked me a few questions about how much insulin I was using and what kind of levels I had but never asked to see my meter. But I have had a glimpse of the more militant types when I have seen someone else or at my GPs surgery.
I guess I just feel jumpy about having my data scrutinised and also what else they do with the data - I think I will ask them for their data policy to see if they share with anyone else.
Click to expand...

Hi,

I had a great doc who retired a few years back.

Your diabetes is your business. I empathise It can feel personally invasive.
It's my belief hospital data protection policies are pretty stringent.. Even before covid, only the patient was allowed near the desk whilst dealing with reception. (With a sign pointing this out.) The rest queued a couple of meters back on check in.
 
Hi Hels,
I've the same problem as you have. I keep my numbers low and these are a problem for my GP and others including my wife. My Libra can be reading LO and I'm above 4 and feeling great.

I've been on Libre for several years now and I'm about to try out the Dexcom g6. I expect and hope the accuracy to be a lot better. Can you tell me what the worst features of the g6 are.
 
My Endo told me that the Libre reads low for safety reasons. I use the MiaoMiao and other apps to calibrate and provide her with the data from NightScout. I use Tomato to calibrate as I can’t get xDrip to work. It’s not compatible w the iPhone and US Libre for whatever reason.
 
jimmax said:
Hi Hels,
I've the same problem as you have. I keep my numbers low and these are a problem for my GP and others including my wife. My Libra can be reading LO and I'm above 4 and feeling great.

I've been on Libre for several years now and I'm about to try out the Dexcom g6. I expect and hope the accuracy to be a lot better. Can you tell me what the worst features of the g6 are.
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the G6 was usually reasonably accurate but was also out for the first 24 hours (lower than finger pricking). One really annoying thing about that was I couldn't switch off the alarms for urgent low (below 3.1) so the first night was often very disturbed by alarms or I'd end up switching off the bluetooth on my phone
 
JMcB said:
My Endo told me that the Libre reads low for safety reasons. I use the MiaoMiao and other apps to calibrate and provide her with the data from NightScout. I use Tomato to calibrate as I can’t get xDrip to work. It’s not compatible w the iPhone and US Libre for whatever reason.
Click to expand...

I always suspected that. I think it's a little outrageous actually, any device should be as accurate as possible, we are adults and if we take the time & effort to get a Libre or CGM then we are big enough to look out for our own safety. At the start of using one I would take less insulin (thinking my readings were in the 3s) and eat carby snacks (thinking I was low or going low).All of this is detrimental to my health when I am trying to keep within a fairly tight range. I do like the libre and still use it but I double check with a finger prick now instead of running for a snack. x
 
KK123 said:
I always suspected that. I think it's a little outrageous actually, any device should be as accurate as possible, we are adults and if we take the time & effort to get a Libre or CGM then we are big enough to look out for our own safety. At the start of using one I would take less insulin (thinking my readings were in the 3s) and eat carby snacks (thinking I was low or going low).All of this is detrimental to my health when I am trying to keep within a fairly tight range. I do like the libre and still use it but I double check with a finger prick now instead of running for a snack. x
Click to expand...

I agree that it should be as accurate as possible - I'd say that giving a low reading for safety reasons does the absolute opposite and it more dangerous as users are always adjusting the reading to compensate.
 
I use the Libre and find that readings are regularly lower than a finger prick test. This is causing me issues as my readings are sent to my support team at the NHS hospital.
Now I add notes to the lower readings (below 4.0) to try and convince these "specialists" that I am NOT hypo, often these reading are 2mmol out to the blood test.
Now my major issue with this is the fact that next year 2021 my ability to drive will again be questioned regarding my health issue. This is worrying me because if my consultant is asked about my hypo episodes they may give the DVLA misleading information due to the false lows from the Freestyle.
Anyone got any info regarding this?
 
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