Libre 2 plus

[Westley]

At my last appointment they mentioned I might be moved to this (from the regular Libre 2) some time this summer.
Has anyone here tried it yet?

I'd been hoping for the Libre 3 with it's reduced size - it seems from what I can gather that the 2 plus just has slightly improved accuracy and 1 day longer wear time. Still, any improvement is welcome.

 

[Ushthetaff]

Personally I’m not bothered about size as I use my phone or are you not talking about physical size?

 

[Westley]

Personally I’m not bothered about size as I use my phone or are you not talking about physical size?

I meant the size of the sensor itself. The 3 is smaller diameter and thickness.

 

[TheSecretCarbAddict]

I've ordered my next lot of sensors earlier today and went for Libre 2 Plus. These should be arriving in the next few days. Will report back how I get on with these. But from the website, as it was already noted, it appears that the main feature is the extra day's wear and some accuracy improvements.

 

[becca59]

Never heard of the plus. Wouldn’t want an extra day as like to change at same time of the week. Plus luckily not having trouble with accuracy.

 

[Ushthetaff]

I meant the size of the sensor itself. The 3 is smaller diameter and thickness.

Ah apologies ,

 

[TheSecretCarbAddict]

Just arrived, the first one going on in four days when my current Libre 2 sensor ends. Will try and get some more finger-prick tests in before the current sensor ends for comparison.

 

[TheSecretCarbAddict]

Just arrived, the first one going on in four days when my current Libre 2 sensor ends. Will try and get some more finger-prick tests in before the current sensor ends for comparison.

So, I've now had my Libre 2 Plus on for a few days and initial impression is that, at least for me, it is more aligned with finger-prick tests than Libre 2. My previous Libre 2 sensor seemed to give 1 - 1.5 mmol/L higher reading than finger-prick test, with Libre 2 Plus it is generally no more than 0.5 mmol/L higher and sometimes even surprises me we almost identical reading. For those who are interested, I'll try and pull together some more scientific data summaries over the long weekend to show Libre CGM readings just before and after finger-finger prick test to show impact of lag, etc.

Edit: Added Libre 2 Plus reading spot-checks - phone is CGM, reader is finger-prick test.
Edit: Added the same for Libre 2.

 

[jaywak]

You say the sensor is smaller , can I ask how much smaller ? Some of them readings still seem to be a lot different to the finger prick test though don't they

 

[TheSecretCarbAddict]

Libre 2 and Libre 2 Plus are exactly the same size. It is Libre 3 that's smaller and while I have seen it available via some online pharmacies, I can't afford it as it is more expensive.

The fingerprick test and Libre CGM don't measure the same things, so I don't expect to have exactly the same reading. CGM estimates your blood glucose level based on glucose level in your interstitial fluid. The glucose levels in your interstitial fluid are usually about 10-15 minutes behind glucose in your blood and are not really directly comparable.

Edit: The real question is how well CGM approximates your blood glucose levels and how consistently and if it serves the purpose you are using CGM for.

 

[Westley]

That accuracy does look very good from those checks. Finger prick results from 2 different meters often differ by more than that.

 

[TheSecretCarbAddict]

I've been down a few rabbit holes this morning. As promised here is a bit more detailed data of my Libre 2 vs Libre 2 Plus comparison. A few quick observations / conclusions:

1. This is not a very scientific comparison as based only on a handful of observations, so don't base any critical decisions on this
2. Assuming my glucometer and test strips (Freestyle 2 reader + Optium test strips) provide a good reference I'm not hitting advertised levels of precision (MARD, but this is not the only precision metric that can be used). It is important to note that glucometers come with their own errors and there are many reasons why CGM can be less precise in the wild. How and where the sensor was attached, how long I've worn it, time of day, how quickly my BG levels are changing, and the list goes on... But none of this means that CGM is not useful - the patterns and trends I observed via CGM and glucometer are generally aligned and in fact can be spot on.
3. Another conclusion I arrived at was that while newer generations of Libre are getting more precise, the actual improvement is negligible and given other real-world influences on your readings as per above probably won't make that much of practical difference. So my improvement in precision between Libre 2 and Libre 2 Plus most likely driven by other factors than improved precision per se.

I'll stop rambling and maybe one day do a more considered write up.

 

[Sizewell]

I have heard that with Libre 2 plus that there is changes to the encryption so is currently unreadable by Xdrip+.
Juggluco will read it as it uses some Librelink libraries to do so.

 

[TheSecretCarbAddict]

My Libre 2 Plus sensor packed up a few days before the expected wear end date with Replace Sensor error. Was working well up to that point.

@Sizewell - I can't comment on those other applications as only using this with the vanilla LibreLink app.

 

[EBe66]

@TheSecretCarbAddict Great work!
I didn't know about the existence of a Plus version to this very moment. Unfortunately I can't buy it yet in the Netherlands it seems.

Just one question though, when the sensor stopped, did you replace it with another Plus version sensor? And more to the point does it have the same observed accuracy as the first one? Bit early to tell I assume, but I would love to know if this was just a lucky very "good" sensor or if the Plus model is really better.

 

[TheSecretCarbAddict]

I've gone back to Libre 2 to use up one of the previous sensors, but will do some tests on this once settled and then do Plus version after. As I said though the difference in reported precision for 2, 2 Plus, and 3 is miniscule. My prediction it is down to sensor, but let's test.