Tuesday, 16 February 2016


No, you haven’t clicked on an old link, or got here in a TARDIS, this is really a FreeStyle Libre review written in 2016.

I’ve finished my first 14 day stint with a sensor and I’m thinking about what I’ve got from having it.  This is old hat to a lot of people so you can skip the TL;DR stuff if you want – I won’t be offended.

The general reaction from anyone in the Diabetes Online Community regarding the Libre is “Oh how are you finding it?” – a fair question to ask, but not necessarily an easy one to answer.  Before I plugged myself in for the first time, I wrote about why I’d waited so long and what I was really hoping to get out of using the almost-CGM system.

So how did I find it?

Well putting the sensor on in the first place took a while.  I don’t think I’ve ever seen a more intimidating set of packaging in my life so it took a fair amount of courage/encouragement/mocking before I pushed the thing in.  Yes OK it didn’t hurt, but it look like it would so I stand by my reticence.    I’d plugged it in a little before bed so I’d have an overnight set of info to look at in the morning.

I’d set the boundaries on the reader to be between 4.8 and 7.8mmol.  I’ve no idea what other people do, but it seemed like a sensible enough range to me as that’s where I’d like most of my readings to be.

I think my overall experiences of the Libre in the first and second weeks were quite contrasting.   The first week felt positive – I had more information that I could understand and act on.  I don’t think the benefit of the directional information can be understated but it is equally important to fully understand what that information means, and how accurate it is (compared to a finger-prick test).  I was wary of effectively chucking all my old testing kit in a cupboard and solely relying on something new.  I tested almost as much as normal for the first 3 or 4 days before I got comfortable with it.

About as close as you're likely to get

The second week wasn’t as encouraging.  I got to a point where no matter what I did, the Libre was showing me as “Lo”, or under 3mmol when my finger-prick tests showed something entirely different.   The thing with diabetes is that more often than not, you can feel if your BG is too high or too low and often you test to see how high or low it is so you can treat accordingly.  Suddenly seeing “Lo” on a reader (BG < 2.2mmol) when you feel fine is quite disconcerting.  One of the biggest discrepancies I saw was the Libre reading 3.5mmol and my BG meter showing 8.9mmol.  I know there’s an inherent lag of around 10-15 minutes, but even that didn’t explain the constant low readings.

The arrow is deceiving, as you can see from the constant flat red line...

After about 10 days, I’d pretty much given up on relying on the Libre readings in any way (though I carried on scanning it to see how it was behaving).  A day or so before the sensor died, it had got itself back in order to a degree – constantly reading about 1.5mmol lower than a finger-prick test at any given time.  (It’s worth noting that this point that when I phoned Abbott, they agreed to ship me a replacement sensor as obviously those sorts of deviations aren’t good).

So what did I learn from this first foray into 24/7 data?

Well firstly, considering the three things I wanted to understand more about, I definitely noticed a dip mid-morning and having observed it for a few days, I tweaked my basal settings slightly and noticed the effect of that lessen somewhat.

Mid morning dip at about 10am

Regarding exercise, the Libre confirmed pretty much what I suspected, in that the approach I have at the moment (temp basal, few jelly babies etc) seems to work really well for me, with no noticeable spikes or dips.  Being able to keep that stable BG over distances up to around 10 miles is encouraging.  

Short spike before running, in range (and rising) at the end

Finally the occasional evening/overnight spike… it’s definitely there!  Work to reduce its frequency is ongoing.


Secondly, I was amazed at how much having the sensor can influence your behaviour – whether you want it to or not.  I’ve read blogs over the last 12 months likening having a Libre to being like a game (think Flappy Bird) where up and downs within the blue band are OK, but do what you can to keep it within those boundaries.  Even after about 24 hours use, I can see how it gets that addictive and I was modifying my approach to self-management to try and keep a flatter line.  I’m more likely to bolus 5-10 minutes before eating now as a result of the Libre.  I’m also more likely to try and ‘nudge’ my BG in the right direction if I see it falling or rising quickly.

Cured.  Sort of.

The flip side of that is that diabetes with a Libre is a full time job.  More information seems to breed more action, which in turn breeds even more information.  If moving from pens to a pump is more of a constant reminder of living with diabetes, then throwing a Libre into the mix is basically signing your entire existence over to it.  I also think that the abundance of information is meaningless if you aren’t understanding and reacting to it properly.  Stories of people treating high BG with temp basals, or constantly fiddling with those basal settings every few hours of every day to try maintain a flat line isn’t (in my humble opinion) helping.  I think if you’ve got access to the information you need to be able to look at it objectively and make longer term changes.  I think information overload can easily be a contributing factor to diabetes burnout.

Obviously, the readings from the Libre are great when you can trust it.  Once you can’t, it becomes meaningless.  I don’t know how often other people finger prick test alongside scanning, but I felt like I needed that reassurance that the daily graph was worth looking at.  Towards the end of the sensor, I felt very demoralised by the whole process if I’m honest.  I felt like I was suddenly second guessing my every move, faced with a lot of information and decisions that I couldn’t make sense of.  I’ve had type 1 diabetes for 13 years and I haven’t been in a position where mentally, I felt like I did last week in about 10 years.

Finger-prick results never read below 4mmol...

Finally (you’ll be relieved to read), I was surprised by the little differences the Libre made.  I was really conscious of not laying on the sensor while I was sleeping.  I was very conscious of knocking it while I was walking or showering, and even getting dressed became quite a cautious activity.  I’ve no doubt that’s my own personal risk aversion, and not the experience of the majority, but it was definitely a noticeable behaviour change.

So where do I go from here?  Well I’ve got one more sensor at home, and a replacement on the way, so the experiment will continue.  I’m going to wait a week or so before going again (so it coincides with being away for a week, where I think the convenience will be most beneficial).  I definitely think an accurate sensor could play a very positive role in my life with diabetes, and probably lead to improved HbA1c results.  

From the first week, where it worked properly

I suspect that more frequent use would mean those behavioural changes become more normal (or at least less noticeable).   I don’t want my life to be 50 scans a day, along with constant small insulin doses or 5g carb snacks.  That’s not living to me, that’s just existing.  I want the ability to test at convenient times, get information I can trust, and learn how I can make simple adjustments, to remove the variability in my BG as much as is reasonably possible.

So is the Libre for you?  I can’t tell you (and neither can anyone else).  Like a pump, it’s a personal decision that you have to investigate for yourself.  I think it’s worth investing £130 (if you can spare it), to get a reader and two sensors so you’ve got enough time to make an informed decision.  If you’ve made it this far through the post, hopefully you’ve got some things to consider for yourself, but what works for me might not work for you (and vice versa).  However you choose to manage your diabetes is an entirely personal thing, and don’t let that change.

1 comment:

  1. A very interesting read Andy, shame the sensor went loopy but glad they're replacing it.