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Freestyle Libre sensor Serious inaccuracies- Help us improve this!


Interesting. I still think that the libre documentation can be improved. Mind you, they say you should do a finger BG testing ONLY if you get from the libre an indication OR if you feel something is wrong. I had various cases where all seemed OK, yet i still opted to do a blood test and it reported a level 40% higher (see my youtubes...) I don't think that's acceptable.
 
SamJB said:
The Libre has been life-changing for me; I hardly every finger prick, avoid lots of hypos and highs, can easily test in the night, can test subtly. If you don't like it that much, don't use it and get a CGM instead.
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Same for me, been a complete game changer - especially when I used to test rarely.
 

That being the case pls report it. Only via your reports on the form 3500b can we get the Libre company to react. See the youtubes wheer i share unfortunately similar, if not worse, experiences and mind you i am tech savvy...
 
I agree with @SamJB

Abbott are perfectly clear about what the Libre does, and doesn't do.
There is plenty of information in the accompanying literature discussing the limitations and correct testing protocols for insulin use and driving.
Unfortunately, it appears that many people don't read these clear instructions.
 
TuviaDror said:
I had various cases where all seemed OK, yet i still opted to do a blood test and it reported a level 40% higher (see my youtubes...) I don't think that's acceptable.
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In that situation, a phone call to the Abbott Libre helpdesk would have resulted in a replacement sensor being sent to you, at no further cost to yourself. They would have sent you a plastic envelope to return the faulty sensor so that they could analyse the problem.

Absolutely no need to continue to use an obviously wildly inaccurate sensor, AND an opportunity to help Abbott improve the quality of their product.
 
You are right. I did exactly as you suggested- called the libre help center and i got a new sensor and even more than one. They were very nice!! Unfortunately though, similar issues recurred. In one or two out of three sensors it occurs with me. Thats too much, in my opinion. The annoying thing is that i asked to speak to the libre head quarters in the USA. They never got back to me. So annoying. Though i reported it > 2 months ago and they promised to get back to me. Thats why i reported it to the FDA....
 
TuviaDror said:
. . . . . the magnitude of the problem
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The magnitude you are suggesting doesn't correspond to the following article http://abbott.mediaroom.com/2017-02...oved-Glucose-Control-for-People-with-Diabetes.

Personally in the 18 months that I've been using it, it has only caused concern on one occasion when it was obvious that my BG wasn't as low as 2.5. I use to check with my Accu Chek Mobile Blood Glucose Monitor once every day for several weeks. The FS Libre was close enough for me not to worry about it any more. Guess I'm just lucky it's been such a game changer in my life.
 
Britishbob said:
Unfortunately this website allows people like you to make wild claims - how does know what you claim is accurate
Need say no more that you think the Libre measures BG - it doesn’t
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Fair enough. I could be making false claims but i have a FREESTYLE pdf generated by downloading all the data from the libre reader and BG finger test reader, integrating the two in one file. This shows that what i say seems to be accurate- by their own software. This website is limited to 1MB so i will refer you to the american website ttps://community.diabetes.org/ where i made similar claims but was able to upload several files. Hope this helps and Hey you are right- we must verify the authenticity of claims! The thread/post is called "Freestyle Libre sensor - Launched too early? Serious inaccuracies- Help us improve this!
"
 
@TuviaDror - I'm not sure how long you think the Libre has been on the market, but it's now a good four years, and the sensor tech is the same as that in the Abbott Navigator. So there's nothing wrong with that.

It's also well known that the Libre is not considered to be all that accurate for a fair number of people, however, plenty of others find it to work incredibly well. You are one of those for whom it doesn't. With the best will in the world, there are more Libre users than Dexcom users, so the small percentage complaining will just continue to do that. Without wanting to seem rude, as a corporate, they will understand that there is a proportion for whom the device doesn't really work and will therefore accept that they aren't able to supply you.

The thing that is really driving Abbott's desire to improve accuracy is the use of the Libre system with Bigfoot's APS system. The first step of this is to improve accuracy (a MARD of 11.4% doesn't really cut it in AP world) and as someone else mentioned, they are changing the way the calibration is done, which appears to have a significant improvement with Libre 2 (and the US 14-day sensor as well from what I understand).

So while you can continue to complain and letter write, both the FDA and Abbott will turn around and say:
  1. Abbott is already improving the accuracy
  2. These systems do not work for everyone
  3. There are already a ton of warnings about high and low readings and what to do with them
It appears that most people are already aware of the limitations of the device, and the key use of it is for understanding the dynamic nature of glucose levels and what you can change to reduce spikes and lows.
 
Tim,
First off, thx for your detailed and VERY informative reply. Your perception is very well backed and seems to be very well educated.

Per the points you made it, you are correct. The device DOESN'T have to work for everyone. Its fine even if it works for just 10% of the target audience. However, for those that it doesn't work on it must give an indication. It cannot mislead them by providing a measure which is erroneous without providing a warning message. The FDA is extremely careful with that and 100% unforgiving- with diabetes it can be dangerous giving too high a bolus....

Per the warnings they provide- unfortunately they do provide a ton of potential warnings but, at the same time, they are missing many conditions they should have reported "we can't measure accurately and are off by more than 20% potentially..". They are missing them primarily, in my opinion, due to the fact that they are not comparing to a finger BG test every so often (as their competition do).

Finally, as you saw, a considerable subset of users became aware of the flawed reporting on our own and stopped using the libre. The concern is that there is a remaining less educated subset of users who are unaware of the flaud reporting and can be thus be prone to mal treatment (wrong boluses). This is not acceptable, especially since all that has to be done to take care of this is to incorporate finger BG tests.

I believe the FDA is aware of this, of the risks due to non incorporating the finger BG tests, and i hope they will react in a way
that will prevent unjustified harm from a non-negligible proportion of diabetics WW.

Thx again for sharing with us your perspective. So far it seems like there are many who had similar experiences to mine (see also the USA site post) and Im sure soon Abbott will react appropriately.
 
You're missing the point here though. Outside the US, the Libre isn't licensed for dosing insulin and the FDA has no influence, so why would non-US people be concerned about accuracy in that respect? They are already told not to use it for insulin dosing.

I do think you have to be wary of the numbers you state - even the FDA doesn't expect that 100% of readings will be accurate. Otherwise neither the Libre nor the Dexcom G6 would have been approved for dosing without calibration (and believe me, Abbott have absolutely no plans whatsoever to add calibration into the model for Libre).

The FDA has just approved the 14-day Libre in the US, which apparently has a better MARD (9.4%?) than the 10-day (10.7%?) which would suggest that they are happy with the way that Abbott is handling improving the accuracy of the system and they won't require calibration. I suspect you'll soon see the 10-day sensor phased out.
 
Tim. Thx for prompt reply.

Actually, I believe the FDA IS looking into this issue. Sufficient complaints (thank G-d) triggered an investigation.
Per the rest of teh world, you bet the libre affects insulin dosage- pls look at whats happening in UK. DItto for the US. The MARD is irrelevant here. If we have a sufficient number of patients who will be grossly affected (a safety issue) by very large errors of the libre (take a look at the 3 months data i have on my USA posting- you will be startled by the unacceptable deviations) , FDA will intervene. They have in the past and i believe will again. Abbott can not ignore the necessity of calibration/validation by finger BG tests. The FDA i believe will help them comprehend that.

Lets stop arguing about this. Wait 3 months and see.
 
There are 1,000,000 of us who are finding Libre life changing. We find it sufficiently accurate whatever you say. You would seem to have us without any new technology. We will take whatever we can get to keep us alive and improve our lives. We are very pleased with the work that Abbot are doing for us

Sorry, Admin - it needed to be said.

Edited by mod for personal attacks.
 
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The Libre didn’t work for me. It started with poor reading and I had anaphylaxis because of something on the adhesive. Though this was yellow carded I think this is possibly the most important thing happening in the diabetes community at present and I’m so excited for the community. I have written to my mp (useless but still). Libre were very fair to me and in the end despite them offering to replace constantly I made the decision that I was one of the people it doesn’t work for which they made completely clear was the case.

I’m not sure what my point is.
 
@TuviaDror - I think you are missing the point a little here regarding the UK. If people are dosing off a device that they have been told not to and can't use for driving, and that has no license to market that way (so isn't, in fact it was one of the complaints about the tagline "why prick when you can scan?", because there are plenty of times when you do have to prick), regardless of whether you complain (ie in Europe), you have no recourse, so it becomes a choice that you make and are responsible for. It's kind of irrelevant as to what the FDA does at that point - you were never told it was safe to dose insulin off the Libre in the first place and the FDAs jurisdiction extends only in the US.

Don't get me wrong, I understand the issues with accuracy, and have written a lot about it, but in a place where the approval is explicitly stated not to use the Libre for dosing off the sensor and to check when you get both high and low readings, we are much less bothered about the accuracy - no it's not great, but frankly, it doesn't matter that much.

In addition, the thing I find fascinating is your complaint about treating or not treating lows, or not bolusing when the Libre was showing low, when the very first page of the Libre manual states, in the Safety Information:

Ignoring the missing high readings, what is Abbott supposed to do when it tells you directly in the safety information to check lows or impending lows with a fingerstick, and you don't? In your moan in the US forum, you stated:

When you were completely ignoring the safety information. How is that the manufacturers fault?
 
@tim2000s I'm reminded of the story of woman who sued a Microwave company because it didn't say in the instructions not to dry her dog in it as she had been accustomed to doing at low heat in the cooker oven
 

Tim,
Thank you very much. I was indeed missing a point and thanks for elaborating. I REALLY appreciate your comments and taking the time to share with me these pieces.! The last thing I, or anyone in this great community i hope, would like to do is deprive the so many successful Libre users of what was obtained. Why should we? I'm sure you and the rest of the community to, would be happy to increase the size of population benefiting from it (including us few, but not so few, who had "issues" with it). I really see it as a good pattern presenter. I'm just afraid that despite the handful of warnings, diabetics still use it not only as a pattern displayer but also deduce from it the bolus required. Wouldn't you if you were not that technically Savvy??- I mean if someone says to you you have 200, or 250 mg/dL in your blood, wouldn't you give a bolus? On the flip-side, if you have a display of 100 or 90 by the Libre and feel fine (with no physiological indications of a high sugar), would you even consider giving a bolus (or doing a finger blood test)? By missing that bolus, your avergae BG can go up (and obvioulsy teh HbA1c as well). Hence....I was just thinking that perhaps The libre could just present a graph, without actual numbers.

Or perhaps even if Libre would provide, instead of numbers, just HI LOW and MEDIUM and perhaps show a graph of what they are measuring (without displaying actual numbers), then it would be safer and no one would gauge of it for actual blouses (or missing on them). That's all i suggest (and Abbott aren't getting back to me, just totally ignoring me). Maybe you have a better suggestion? Can you perhaps discuss with them?

Incidentally, i am posting below a response i got on my USA thread in the ADA community. Seems like in the USA, issues i reported are occurring to... I truly hope sales of teh Libre will NOT fall but increase, together with solving/attending to the issues i reported....

Any advice of yours, as to solving this issue, is much appreciated.
Thx again!

Re: Freestyle Libre sensor - Launched too early? Serious inaccuracies- Help us improve this!
Posted by Caloh on Nov 19, 2018 3:05 pm

Yes, I did have a similar problem with the Libre, in that it was reading way too low compared to a meter. At first I trusted it, and treated the false lows, not knowing that the info was false. So, I too had an increase in my A1C. I stopping using it, went back to my meter and my next A1C was back to my normal.

This past Nov. 10 there was a Diabetes Expo at our local medical school and I spoke to the representative from Libre. I told him about how it read low for me and how I wished one could calibrate it with a finger-stick like ordinary CGMs. He would hear non of my complaints, insisting that the Libre was just as accurate as a meter.

While the Libre is easy, even fun, to use, it is very misleading. I think when lots of us start getting higher A1Cs, sales will fall off and it is the company's fault. There are other products in the wind that will be coming out in the next year. I hope they will be more accurate.
 
You come back to the same point though, because we're talking effectively about two different products.

In Europe it is not licensed to be treated from. You do so at your own risk. It is clearly stated that this is the case, so if you do it, then why would Abbott be the ones in trouble? "Don't use this data for treatment decisions" is pretty clear. It's also why the bolus calculator only works off a blood test.

With the best will in the world, I would expect that the FDA would simply remove the approval for making treatment decisions from the 10-day Libre (which by that point is likely to be irrelevant anyway, as they will be fully replaced with 14-day version). Then you're back to "It's the user's decision".

Have you run the same tests against the 14 day version, which Abbott says is more accurate?
 
Actually, I've been using the 14 day version only. I never used anything else.... Does that still make sense? Despite me using the 14 day version, and the person i quoted in the USA too, where one is supposed to read off the libre the actual BG level and calculate a bolus, we (Caloah and I and others...) obtained readings which are inconsistent with finger BG test?
 
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