I rely on my Dexcom CGM because it alerts when I am not testing. The Libre is an exciting technology, but it is somewhere between traditional BG testing and a full-featured CGM.
I'd like to see data from clinical trials supporting the accuracy of this device, because I'd like to compare it to said data for the Dexcom G4.
I find it hard to believe that this device doesn't require calibration...
And without the alerts, I'm not sure I would find it useful.
From DiaTribe link above:
Freestyle Libre’s Accuracy Updates:Freestyle Libre’s accuracy vs. fingersticks is 11% (e.g., if blood glucose is 100 mg/dl on average, the system would be off by about 11 mg/dl, on average). This accuracy is roughly comparable to the Freestyle Navigator II (12%) and slightly better than the Dexcom G4 Platinum (14%) and the Medtronic Enlite (14%).
So my question is if we get one of these we don't have to finger stick very often at all prolly? In that case you could use it along with dex as your calibrater etc.
Those sensors are pretty expensive though sans insurance, does anyone know how long they last?Sensors last 14 days, no more. It's electronically limited. From the DiaTribe source:
Notably, FreeStyle Libre is approved for dosing insulin except in three cases: when hypoglycemic, when glucose is changing rapidly, or when symptoms don’t match the system’s readings.
If the flash glucose monitoring, or FGM numbers correlated well and dependably with fingersticks and symptoms, the fingersticks would be few. I would expect to do 2-4 each day instead of the 12-15 I do now.
I would try use it to calibrate my Dex and see how it goes. It's certainly as accurate as a fingerstick reading.
You're right, Laddie. This is definitely not a replacement for the CGM. I've been alerted countless time for hypos by my CGM at night and other times I didn't realize it. I rely on a Dex, too.
My self monitoring of blood glucose strip expense is substantial. I use about 4800 strips per year. I'd gladly swap a huge quantity of strips for the flash glucose monitor. Not to mention a rest for my fingertips!
I want one, thanks for all your comments Terry. At one time I used the MM CGM and was not a fan, so I would rather use this than try the DEX. I just want to know my blood sugar now, accurately, with no lag time, and I could keep swiping to see the trend. Just my two cents. Also I have used the freestyle lite for years with no issues, so I kind of trust Abbott. I use 10-12 strips a day, and freestyle lite strips are pricey. Would love FDA approval and insurance coverage eventually, but I would pay for a test drive now. I am always testing because of hypoglycemic unawareness and when I was on the MM CGM I still had to test if it was trending low to see if it was accurate. Mostly it started to give me false readings when my blood sugar was fluctuating.
I think I definitely want one of these but I would have to wait until it is approved and my insurance will cover this because I think that is too expensive for the sensors. I have to say even though dex has made some mistakes it has been pretty accurate a lot of the time and is allowing me to do less finger sticks I think... I will have to tally it up and see. I know I said I would never do this but I have treated at times off Dex readings too. It seems to have the most trouble when my bg is moving fast and also missed two lows when it wasn't dropping fast. It is so odd to see how your bg is really moving around... I have found my bg goes up often after taking insulin, very odd. I knew that from finger sticks already.
Karen - I'm glad you don't mind all the comments I've made in your post. When something excites me, it stimulates my interest.
While both the Dex CGM and the Libre measure glucose from interstitial fluid, Abbott has somehow massaged the formula to get the lag time down to five minutes if the BG is not quickly trending up or down. The fact that they say their instrument is OK for dosing insulin, with a few exceptions, gives it one big advantage over a CGM.
I've used my CGM to dose and while it's usually OK, sometimes I am burned by it. It's especially dangerous for me when I go low and start throwing carbs at it. If I'm not finger-poking to catch the first hint of an upward BG trend then I will always over-treat and go high.
I find it an interesting psychological effect that watching my BG data stream makes me want to push it in a favorable direction. Some people would assign that level of interest as obsessive, but I find that the more I watch, the better my numbers get.
The CGM data is essential for me. I've learned so much. My numbers are not perfect, far from it. I struggle as much as most of us here. I'm just recovering from a two week bad patch.
But what I've learned is what is possible when everything clicks. I've actually had nights when my BG stayed in a tight 30 mg/dl band, 90-120, for nine hours. I would have never thought that possible without seeing that trace on my CGM.
I wouldn't give up my CGM for the FGM (Libre); the CGM alert capability is a life saver.
The indication that they do not need a caveman fingerprick reading/cal is suggestive that they have a extra oxygen sensor that can read the o2 levels and create absolute readings.
That is reason for the calibration readings on a daily basis on the Dex. This was suggested by folks making a long term sensor and desire to get absolute readings.
I still want to get one of these beasties and try.
I want one as well, sign me up twice.
Technically you don't need a prescription to buy glucose meters (or CGMs) in the US. You need FDA approval to sell them. I believe it is the same in the UK. The EU in general has been faster to approval medical devices and medications. Whether that is good or bad I don't know.
I believe the results reported at EASD are the results reported by the company's study. It doesn't state how accurate this is against a standard reference (it may still be close to +/- 20%) or against the ISO standard and it doesn't give the percent of readings with +/- 15% or +/- 20%. And being a company study should just not be trusted much. The real truth will come out as we (as patients) use it and independent studies get reported in places like the Diabetes Technology Society.
That's the thing. It's basically going to be a small test on the public who can afford to pay for it...which over here will be a tiny group. Much in the same way Dexcom operate in the UK (or don't really since they just sell the stuff and won't deal with the NHS). If they get NICE certification, than fine, it might become more readily used but currently the cost barrier means it won't become widespread at all.
Once certified by NICE, my suspicion is that it will basically become the chosen CGM for use with Abbott pumps (or a future pump to come out) since Dexcom aren't certified. Without the Dexcom the Vibe is currently lacking CGM support which has left Abbott at a major disadvantage in the UK to compete with Medtronic in this area which this will combat for them hopefully.
Is it better or worse than something like a Dex or Enlite. We don't know yet. Is using an RFID reading system a good idea...quiet possibly if only for power saving. It's an interesting device yes, but guess we'll see what happens if/when it gets certified. Price wise though it's half the price of the Medtronic equivalent and last fast longer, which should get it through certification in the UK in no time.
Okay I read this fully and now I really want one
Thanks for adding this, Brian. I understand some basic statistics but I've yet to read a layman's explanation of MARD or mean absolute relative difference. I, too, would like to see independent verification of company accuracy claims.
Nyadach - Great to get some comment from the UK. I've seen reference to NICE but wasn't really sure what it is. Your comment sent me looking. I found that NICE stands for UK's National Institute for Health and Care Excellence.
I found some details on NICE at this website:
NICE's role is to improve outcomes for people using the NHS and other public health and social care services. We do this by:Producing evidence based guidance and advice for health, public health and social care practitioners.
Developing quality standards and performance metrics for those providing and commissioning health, public health and social care services.
Providing a range of informational services for commissioners, practitioners and managers across the spectrum of health and social care.
I think it is short-sighted for any public health policy to limit visibility of blood glucose and blood glucose trends. In the long run, PWDs will benefit from BG awareness. This will lead to the NHS and other systems saving money, not spending more. I guess part of the responsibility to educate the public and policy-makers about the real economic truth of this matter lays with us PWDs.
Freestyle Libre is headed to the U.S., but the company had declined to disclose a timeline. And there are high expectations for its sales potential. About the system, Abbott chairman and CEO Miles White said on a July earnings call, "That, we believe, will be a significant growth driver for this business here over time, and it will come to the U.S. and it will be a global product."
Nope -- delay is the same. This is function of subcutaneous interstitial fluids, not a function of the sensor technology. Glucose levels in these fluids lags circulating blood levels by 5-10 minutes or so.
What makes it worse, this is not a reliable metric; it depends on activity level, the location on the body, and all sorts of other variables that affect perfusion at the site.