Readings

[EmmaL76]

Hi all, so quick question, my libre 2 always (I mean always ) reads at least 1 but mostly 2 points higher that finger prick. I thought this might be due to a slightly off sensor at first but since changing several times it’s always the same. I understand during bg fluctuations there will be differences but this happens all the time during hours of stable bg. Example, waking sensor 5.7 finger 4.5. Hour after breakfast showing sensor 9.8 finger 7.5 ( okay so it could of been in the move then) 3 hours after breakfast, libre shows I’ve been steady 7.5 for a while but finger is 5.3. Anybody else noticed this? Also I know they say you should mainly trust the finger but what is the reason for this? What makes it more accurate than my bodily fluids. Sorry actually wasn’t that quick of a question !

 

[Kaylz]

Glucose reaches the bloodstream faster than it hits the interstitial fluid, it lags at least 10-15 minutes behind blood

As it's measuring different things it's highly unlikely to ever match perfectly, most peoples tend to read lower than bloods though although I have had occasional sensors read higher, some of us find them better for spotting trends rather than trusting the reading fully and as long as it's consistently out by the same it can still be very helpful

Sorry that hasn't really answered your question I don't think lol xx

 

[leonS]

If you are using a different finger meter, and not the one built in to the Libre, it could be that that meter has a constant error. If tiu are using the Libre for both tests it might be an idea to contact Abbot and ask for their comments.

The Libre does not measure glucose in the blood, as you are aware, so the reading lags behind what the BG is doing. Also a calculation is performed to change the result that the Libre obtains to what the BG can be expected to be. This need not always be accurate.

In effect the Libre says "I checked the glucose in your body fluid and according to my calculations your BG (about 15 minutes ago) was ...

 

[EmmaL76]

Thanks guys for your comments. I use a separate meter for finger pricks Leons, but I do have two so I’ve been checking both at times. If I’m honest this has only happened with the libre 2 which seems odd with the 1 it was more common to be lower than higher. Kaylz your spot on with the patterns stuff, totally amazing for that… still wouldn’t wanna be without it

 

[Robin]

Thanks guys for your comments. I use a separate meter for finger pricks Leons, but I do have two so I’ve been checking both at times. If I’m honest this has only happened with the libre 2 which seems odd with the 1 it was more common to be lower than higher. Kaylz your spot on with the patterns stuff, totally amazing for that… still wouldn’t wanna be without it

My first two Libre 2 sensors earlier this year both read about 2mmol higher than a fingerprick, whether I was rising, falling, or the same. And both the inbuilt Libre meter and my old Acuchek agreed with each other, but not with the sensor. The next two sensors I've used have been spot on, though, and I wondered if there’d been a dodgy batch, or whether they’d tweaked something.

 

[EmmaL76]

My first two Libre 2 sensors earlier this year both read about 2mmol higher than a fingerprick, whether I was rising, falling, or the same. And both the inbuilt Libre meter and my old Acuchek agreed with each other, but not with the sensor. The next two sensors I've used have been spot on, though, and I wondered if there’d been a dodgy batch, or whether they’d tweaked something.

Well Robin that very interesting and reassuring to know! I know these couple of points shouldn’t make a huge difference but I’m at quite a delicate time on my journey as I’ve recently come off insulin as I suspected my type 1 diagnoses isn’t correct. my DN views the libre data and discusses it with my endo, just don’t want it higher than it should be that’s all. Suppose the hba1c is the ultimate test though.

 

[Robin]

Well Robin that very interesting and reassuring to know! I know these couple of points shouldn’t make a huge difference but I’m at quite a delicate time on my journey as I’ve recently come off insulin as I suspected my type 1 diagnoses isn’t correct. my DN views the libre data and discusses it with my endo, just don’t want it higher than it should be that’s all. Suppose the hba1c is the ultimate test though.

I’ve just checked Libreview to see what my average glucose was for those two sensors, and it was 8.4 and 7.6. I’ve never been so high before, since starting the Libre. The one before, which was my last original Libre sensor was 6.7, and the one after 6.9 (and I was on holiday during that time, so ran a bit higher anyway) I’m currently on 6.7.

 

[EmmaL76]

Well that’s it then! We either had a dodgy batch or temporarily sweet arms. I have to wait a full 9 days to swap sensor. 😡

 

[helli]

@EmmaL76 does your DN view your Libre data with you or does she look at it online?
The reason I ask is because Libre are "factory calibrated". I find there is something in my body which seems to be different to Factory Man so the numbers I see from Libre are usually out. Therefore, I use a different, unofficial application to read my Libre which uses a different algorithm to convert the readings from Interstitial fluid to blood sugar levels. This different algorithm allows the use of readings from finger pricks to be use to calibrate and I find my readings are much closer and more reliable from the LIbre sensors.
The downside of using these apps is that they do not upload the data to the systems that my DN uses so she cannot see and review my readings without me and my phone.
Another downside is that these apps tend not to have comprehensive (or any) instructions and are pretty complex so not ideal if you are not technical.

I use an app called xDrip and used to use one called Glimp.
Glimp can be downloaded from the Google Play Store. xDrip needs to be downloaded from github.

There are other apps for Apple phones ... sorry, I have an Android so not paid much attention to these.

A less technical approach is to enter a finger prick reading into LibreLink as a comment when you scan so your DN can see that there is a difference.

 

[EmmaL76]

Wow helli thanks for that ! Will take me a little while to get my head around that as it sounds very technical. I have however, as per your suggestion, started adding notes of my finger pricks next to my logbook entries and I already feel much better about life. Last entry libre = 8.9 😡 finger = 6.2🙂 not eaten a thing since 12.30

 

[EmmaL76]

Sorry forgot to say, my dn who I only speak to over the phone just logs in at her end.

 

[leonS]

... Suppose the hba1c is the ultimate test though.

No it is NOT! It measures how much glucose is stuck to the red blood cells and this, in turn gives a very crude indication of what your BG has been over an unknown period of time (about 120 days).

In addition it gives no indication of if this is the result of fluctuating BG or if the BG has been steady. The information given by Libre is very much better even if it is not 100% accurate.

The only advantage of Hba1c that I can see is that it is a single number and so needs limited brain power to interpret. It should be thrown put with the washing up water when better data is available.

 

[EmmaL76]

No it is NOT! It measures how much glucose is stuck to the red blood cells and this, in turn gives a very crude indication of what your BG has been over an unknown period of time (about 120 days).

In addition it gives no indication of if this is the result of fluctuating BG or if the BG has been steady. The information given by Libre is very much better even if it is not 100% accurate.

The only advantage of Hba1c that I can see is that it is a single number and so needs limited brain power to interpret. It should be thrown put with the washing up water when better data is available.

Well that certainly told me😳 just seems to be the main focus of everything. However you did say those with limited brain power find it useful and… ta da … that’s me

 

[Magarr]

Hi. I've just joined the forum today but was interested in this discussion. I've recently made the decision to stop using libre 2. I ran simultaneous Libre and blood tests and found that libre results were,on average, 3.51 points lower than blood. This means that, unless I had reason to doubt the reading in times of low or high BG, I was basing insulin amounts on the lower libre result and so not taking enough insulin. I did this comparison as I couldn't figure out why hba1c was so much higher than indicative libre readings! I've been diagnosed with cheiroarthropathy (diabetic hand syndrome) which can be caused by diabetes longevity but also high blood glucose. I've been using libre for 2.5 years and type 1 for 42 years. I'm gutted that I've been basing insulin amounts on the lower libre readings and may have inadvertently contributed to the cheiroarthropathy. Has anyone else had adverse effects from incorrect libre readings? Thanks

 

[SB2015]

Well that certainly told me😳 just seems to be the main focus of everything

Hi Emma, I think that the HbA1c is still in people’s minds and often used in clinics as before the Libre became Accessible to more people there was nothing else to go on.

i noticed at my last appointment that, whilst they still note the HbA1c, all the discussion we had was around the percentage of time in range (TIR) and the percentage of time that I was hypo. As the sensors become more commonly used I think that this shift will be greater.

As @Kaylz said one of the uses of the sensors is to identify patterns in our levels. Whilst this is from interstitial readings rather than blood glucose it will still follow a similar trend, and in your case this is consistently above your BG. i know I like having the direction of travel of my glucose readings too as that is so much more useful than just the spot readings. As more tech becomes more widely available things will change, but it does take time.

 

[helli]

Time is Range is great but, as only around 20% of people with Type 1 have Libre, HbA1C is the only measurement that is available for most people. I think it is still a useful indicator.

 

[EmmaL76]

Hi Emma, I think that the HbA1c is still in people’s minds and often used in clinics as before the Libre became Accessible to more people there was nothing else to go on.

i noticed at my last appointment that, whilst they still note the HbA1c, all the discussion we had was around the percentage of time in range (TIR) and the percentage of time that I was hypo. As the sensors become more commonly used I think that this shift will be greater.

As @Kaylz said one of the uses of the sensors is to identify patterns in our levels. Whilst this is from interstitial readings rather than blood glucose it will still follow a similar trend, and in your case this is consistently above your BG. i know I like having the direction of travel of my glucose readings too as that is so much more useful than just the spot readings. As more tech becomes more widely available things will change, but it does take time.

Hi, yes I totally understand how important the patterns are , and I do find it really useful for that. I wouldn’t be without it. Hba1c I suppose is great for spotting the initial problem but after that it’s more appropriate to stay in range. I do get that. It’s just (and I don’t know if you have seen my story and sorry if you have and I’m repeating myself) I was only diagnosed last sept, told type 2. I’m skinny so was tested again slight raised antigad but cpeptide showed insulin resistance but good secretion, since then I’ve been treated as type 1. Insulin was causing lows and general feeling like dog poo. One night I missed it and realised sugars were much better. So Ive carried on without just with low carbs and doing all the things I should do , I am putting in huge effort. My DN saw my numbers from the libre (before the issues) and was like wow you are doing amazing! I confessed I wasn’t using insulin and they are now keeping an eye and I have appointment coming up with endo. Problem is these inflated numbers take me from the normal range to the abnormal range and this won’t help my case for not needing insulin. So then I thought we’ll ok hba1c will prove I’m doing good but now folks are saying that isn’t important. Sometimes I feel like I’m losing my mind and don’t know what I am or what I’m supposed to do. So staying in range is all I can do but my darn sensor keeps telling lies 😡

 

[Robin]

So then I thought we’ll ok hba1c will prove I’m doing good but now folks are saying that isn’t important. Sometimes I feel like I’m losing my mind and don’t know what I am or what I’m supposed to do. So staying in range is all I can do but my darn sensor keeps telling lies

I’m now on a prescribed Libre full time, but the hospital still orders an HbA1c along with my other blood tests, and discusses that along with Libre time in range, so it must still see a benefit. It’s still a useful criterion to measure the Libre against. My original Libre used to show overnight hypos when I knew I wasn’t that low, and the hospital were happy to accept that it was reading low, because my HbA1c came out higher than the Libre was predicting.

 

[EmmaL76]

I’m now on a prescribed Libre full time, but the hospital still orders an HbA1c along with my other blood tests, and discusses that along with Libre time in range, so it must still see a benefit. It’s still a useful criterion to measure the Libre against. My original Libre used to show overnight hypos when I knew I wasn’t that low, and the hospital were happy to accept that it was reading low, because my HbA1c came out higher than the Libre was predicting.

Glad you the libre on prescription. I have too
but we are a rare breed as lot don’t and that’s sad. So maybe… just maybe I should stop moaning about mine and be grateful for the resources I have. Pull myself together, stop boring people with my story. At the end of the day, like everybody I didn’t want diabetes, I’m struggling. I want to be how I was before, to be honest I’m a little bit angry. Omg here I go again, for gods sake will someone just shut me up or give me a virtual slap !!!

 

[rebrascora]

Glad you the libre on prescription. I have too
but we are a rare breed as lot don’t and that’s sad. So maybe… just maybe I should stop moaning about mine and be grateful for the resources I have. Pull myself together, stop boring people with my story. At the end of the day, like everybody I didn’t want diabetes, I’m struggling. I want to be how I was before, to be honest I’m a little bit angry. Omg here I go again, for gods sake will someone just shut me up or give me a virtual slap !!!

The forum is here for exactly this purpose, so don't feel guilty or embarrassed or even reluctant about having a moan here. We all understand the need to let off steam occasionally and vent our frustration. The condition takes a lot of mental effort and it often doesn't play by the rules even when we really try our hardest. Our nearest and dearest often don't fully understand the implications of it all, but we can relate to it and in some respects it is important to share those feelings so that others realise how common and normal it is, particularly in the early stages of diagnosis. Talking about the mental stresses of it is as important as the physical aspects, so please don't feel inhibited in saying how it is impacting you.

My Libre reads slightly lower than my BG most of the time and shows that I have far more hypos than I actually do and that causes a bit of a concern when it comes to HCPs viewing my data but I think they understand the system isn't perfect and will take on board your comments, so do let them know that whilst you find it incredibly useful, it is consistently reading high for you. It is always worth doing some finger pricks when you start a new sensor to check how it is measuring up and also occasionally through the life of a sensor. I don't routinely double check hypos or hypers because I know roughly how much higher or lower my BG will be due to those "calibration" tests and I don't finger prick to bolus for food so I can go several days without a finger prick but I scan about 30 times a day to keep an eye on my levels.

I think you need to understand that your HCPs are there to support you with your diabetes management. You have an equal say in what happens and providing that you educate yourself and understand what is happening and can demonstrate that to them then they should listen and respect your thoughts on how you want to proceed. It takes time to build up that partnership, trust and respect for and with them but it is an essential part of diabetes management. If you can show them that you have a good understanding, then they will trust your judgement more. Clearly you have already made a major unilateral decisions by stopping your insulin and you can show that that was a good decision at the time. The important thing is to consistently review that with an open mind and be prepared to return to medication if it is necessary but they have to be able to justify it if they feel it is needed and for you to negotiate a compromise if you can't agree because you do have a say in your treatment.