Showing posts with label gadgets. Show all posts
Showing posts with label gadgets. Show all posts

Posted by on Sunday, 11 August 2024

Hi ho! Hi ho! It’s back to Medtronic I go

MM780G with Simplera Sensors
Medtronic MM780G and Simplera Sensors
(Apple watch not included)

Hello. It’s been a while!

The embryonic posts I had in my mind about living with the Tandem tSlim never seemed to manage to make it to the top of the ‘to do’ pile, and remain unwritten - which I'm sure was a relief all round. But there’s nothing quite like a deadline to spur a (largely ex-) graphic designer into action. And tomorrow I am awaiting the delivery of my new insulin pump, as the warranty on my Tandem tSlim has elapsed. So it felt like a long overdue blog post could no longer be avoided.

Interestingly the ‘new’ pump isn’t particularly new at all. It’s the pump I rejected in favour of the tSlim 4 years ago. This might surprise some people. So why am I not sticking with the tSlim? Or joining the ever-growing horde of podders? But no, for me it’s the venerable MM780G, but with the fancy new Simplera sensors.

So Long tSlim

Confusion about my choice of ‘new’ (old) pump might be even more confusing because I have repeatedly said that I’ve never had better results than with the tSlim. My overnight readings in particular have been spectacularly good, very stable, and never required the alarm/calibration acrobatics that plagued my last days with my MM640G. Automated night mode suited me brilliantly, and I just expect to wake between 5.5-6.5mmol/L every day.

Non-shabby 90 Day Results

Control IQ added approximately 10-15% to my average ‘time in range’ which I choose to set 3.9-9.0mmol/L. My previous general 70-80% has become more like 80-95% most days. This is pretty spectacular with something as fickle, contrary, and annoying as Type 1 Diabetes.

Dexcom G6 mostly tracks my BG levels brilliantly. While I was self-funding (for approx 3 out of my 4 tSlim years) I was able to stretch most sensors to run for 20 days with a viable and solid flow of data, that I was confident to use for most corrections, alerts, and bolus calculations.

So in many ways, I am really happy with the system, and have certainly seen significant improvements from running a hybrid closed loop system. I’d really not want to go back to a pump which isn’t integrated with a sensor and making adjustments.

If anyone is considering the tSlim, I’d say go for it. It’s a very smart-looking and smart-behaving insulin pump. And it might really suit you well.

So why the switch?

Good question! With diabetes gadgets and gizmos over the years I’ve found that the devil is very much in the teeny tiny details. And that even something that’s brilliant, and well regarded, can somehow just not ‘click’ with you and your particular diabetes’ foibles.

This seems to be doubly true with algorithms.

An algorithm is based on a way they expect a person’s diabetes to behave. And how much of an adjustment that person might need to steer things in the right direction in any given set of circumstances. Your own individual diabetes may, of course, have other ideas. But commercial systems being what they are, they don’t really want to offer you much in the way of adjustment or personalisation. It is what it is.

Pretty soon after starting in the tSlim (with only Basal IQ at that stage) I observed that their predictive low-glucose suspend acted much later, and switched off much earlier than the one I’d been using on the MM640G for several years. There were a gradually phased series of basal reductions before a full suspend (really my body needs a full shut-off from the start), and the insulin resumed very soon after an up-tick in sensor values was seen. This was good in the sense that I didn’t have any of those occasional teeth-grindingly frustrating high BG alerts following an over-long suspend. But it was a bit rubbish, on balance, because only the most gentle downward-drifts were caught in time for me. Even when I activated ‘Exercise Mode’ for such strenuous exertion as wandering round to the shops.

In the old days I’d have set a Temporary Basal Rate to start things off early. But Hybrid Closed Loops don’t let your set TBRs, because... well... they are supposed to be doing all that stuff for you.

I experimented with setting essentially a fake TBR basal profile of 0.1u/hr for the 24 hours and activating that at the start of dog walks and such... But then, inevitably, I’d forget to switch back when I got home, because TBRs had always just cancelled themselves after a set time. Following an update of the Control IQ software I was able to completely suspend the pump for a defined number of minutes after which it alerts to restart. This was OK, but for reasons I cannot really understand this also silences any alarms of impending hypo/dropping BGs the pump might helpfully provide if basal-suspend isn’t enough on its own, and levels are getting a bit close to the edge.

Dex lag and alarm fatigue

Initially I was blown away by how well the Dexcom G6 tracked my BG levels. Whenever I did a ‘how are things going’ cross-check the results between fingerstick (Contour XT) and Dexcom G6 were only ever a few tenths of a mmol/L out. This gave me huge confidence. But at some stage in the first year I observed that the problems I was having with the late action of tSlim’s predictive low-glucose suspend were being compounded by a distinct lag between capillary glucose and sensor glucose. This isn’t news to me, and I understand exactly why this lag exists, but Dexcom seemed more reluctant to respond to changing values than any other sensor I had used. Almost as if part of it’s ability to match capillary glucose so well when things were stable was bound up in taking extra values and only updating sensor glucose every 5 minutes - perhaps it just waits until it's sure? For me Dexcom G6 is almost always a whole 10 minutes behind moving glucose. And when a ‘this hasn’t worked’ Control IQ alert is happening only 15 minutes before levels dip below 4.0 (and that ’15 minutes’ is what was happening 10 minutes ago) well... some of my increased number of low-level hypos were easily explained. From 1% below 4.0mmol/L to frequently more like 3 - 3.5% - still on target, but I've worked hard to restore flagging hypo awareness and this really can't help.

When is a 4.2 not a 4.2? When it's 10 minutes later

Added to that there were challenges at the other end too. I’d get told that the basal suspend wasn’t enough and to take preventative action after I was already low, and then 10-15 minutes later be told that levels hadn’t recovered, which prompted me to re-treat. Only to then discover that actually that hypo-treatment had been enough, and that the double-treatment was now gleefully pushing me into the teens. Maybe 5-minute updates 10 minutes behind reality are OK for some people - but when I really need to know how things are moving at the sharp end of hypo-dodging, they were causing me frustration and treatment errors.

The upshot was that pretty early-on I had to take the up reins of hypo-dodging myself again. I set my ‘low alert’ at 5.2mmol/L because (10 minutes behind), that gave me enough time to take action if necessary - with a sensor reading 5.2 and dropping I could easily be low 4s when the alarm sounded and need some rapid glucose to steer away from the 3s. I had the alarm repeat at 30 minute intervals, so that I’d get a reminder to recheck to see any action I’d taken had worked.

But of course it might be that I was just pootling along in the 5s. Getting little warbly nags every 30 minutes. Which was quite annoying.

Even more annoying

But nothing like as annoying as the tSlim’s attempts to actively sabotage my hypo-dodging efforts. Alongside a rapid resumption of the basal profile, the tSlim has, on multiple occasions, delivered a mini-bolus just as my levels were returning to safety after a hypo treatment(!). For meal mis-calculations, or dose-timing errors it never seemed quite so enthusiastic, or effective, at turning around a rising BG, but getting another low alert in the high-4s on a dog walk or while gardening, having successfully treated the last one - and then finding out that it was the tSlim that had caused it with a completely unnecessary mini-bolus, was the inspiration behind some particularly florid and lively outpourings of language over the past 4 years. I asked my consultant whether they knew of workaround/setting to prevent this. Alas none was available. So I had to hugely down-grade my correction factor during the likely hours of evening dog walk, which of course means Control IQ can’t work ‘properly’ during those times when dog walks have happened at other times. And again, setting or not setting ‘Exercise’ mode doesn’t seem to be the fix.

The hollow squares are tSlim autoboluses
 

Better results, but more effort

So yes, I have had better results, and the tSlim has handled many things really well for me. But the alarm fatigue has been pretty tough going. I’ve had a much higher numbers of non-severe hypos than I was used to on the MM640G, and I really miss the discovery that my pump has fixed something for me after the fact, quietly, in the background, with no alarms or notifications required.

Hopes for the MM780G

It was the memory of weeks and weeks with no sub-4 numbers that got me wondering about returning to Medtronic, and giving their hybrid closed loop a try. The pump is the same format, and the chassis is still as clunky and grim as ever (though I’ll be glad to have a screen that’s visible in sunlight again - the tSlim is awful in daylight), but they have updated the software, so it's not exactly like going back in time 4 years.

Medtronic G3 sensors never worked well for me and needed frequent calibration, including overnight. I gather the G4s were significantly better, and I have high hopes for the new Simplera sensors that I’ll be starting on.

I know quite a few people on the MM780G, and almost without exception they seem to get on very well with it. I know there will be frustrations and annoyances - there always are. But I’m hopeful I may be able to experience some of the “spending less lime thinking about diabetes” that others mention. On the tSlim I think I’ve had to think more - constantly checking up on what it’s doing, and fixing some very silly decisions it was making from time to time.

I’ll let you know how I get on.

Posted by on Thursday, 31 December 2020

Hype or Hope? Dexcom, Tandem tSlim review and 2020 round-up

Wait... hang on... December 31st? That can't be right! Have we actually had a year this year? And how come any of the things that happened this year seem to have happened at least 18 months ago? No time has passed. But it has passed at a snail's pace. And at the same time we've all become accustomed to living completely different lives.

Doing a sort of round-up post for the year that never happened doesn't seem worthwhile. There are only so many times I can talk about avoiding a Zoom-based diabetes thing before I'm going to run out of waffle. Yes even me.

tldr; 2020 was a bit pants. But I really like the tSlim and Dex.

Tandem tSlim Insulin Pump
Tandem tSlim with Dexcom G6
Out with the old
I've been meaning to write a post or three about my experiences of the Dexcom G6 and my switch to the Tandem tSlim:x2 (and subsequent upgrade from Basal IQ to Control IQ) since the Summer, but for all sorts of reasons that series of posts never arrived. I have lots of pics of pump and graph cluttering up my phone that were apparently going to eloquently show something or other, but it's all so long ago now that I can't really remember what it was I was going to say.

I am self-funding Dexcom G6 sensors, and it was the first time I had used Dexcom. Such is the relentlessness of the positivity around Dex, that I think secretly I might have been hoping that I wouldn't find it all that special. 

I sprung for the 'starter pack' which gives an official 30-day's worth of coverage before I committed to going for the tSlim, so that if my body chemistry didn't get on with the Dex I could opt for Medtronic's MM670G (or similar) with self-funded Guardian G3 sensors. I had always got on well with Enlites and to some extent G3s too, and I was pretty sure that I would have got on well with the MM670G if that was what I'd gone for.

Inserting the Dexcom sensors was really straightforward, and initially I ran the sensors with my iPhone (not yet having taken the plunge on the pump). They restarted easily, and I didn't even have to faff about with unpeeling tapes and removing the transmitter thanks to these instructions. What really struck me though, was how well the factory calibrated G6 tracked fingerstick results from my Contour Next Link 2.4 meter (still my go-to BG meter). The first few days were uncanny. Spooky even. It didn't appear to be hype at all - generally Dexcom was reading only a few decimal points away from any fingerstick I took.

Dexcom G6 lagging a little against hypo recovery
Even a Dexcom G6 lags a little now and then
Reassuringly though, I did see a characteristic post-hypo-sensor-lag on about the 3rd day, where the Dex stubbornly continued bleating about low BG for 5-10 minutes after I was back above 4. So it was a regular CGM and not witchcraft after all. It was just that it was a really good CGM for me.

Joking aside, those early excellent matched pairs (against fingerstick checks) really helped me trust it as a new bit of kit though. 

And even better, while the factory calibration is excellent for me, and I've all but given up cross-checking with fingersticks, if I *need* to recalibrate the Dexcom G6 because it has drifted a little... I can! 

After a few weeks with the Dexcom I was confident to put in my request to switch to the Tandem tSlim when the warranty ran out on Threepio.

Switching to the Tandem tSlim:x2

I affectionately called my first insulin pump robot counterpart 'Artoo' (R2P2 - replacement to my pancreas #2), and kept with the Star Wars theme with my MM640G as 'Threepio'.  This bit of kit promised to be wiser and much more autonymous though, so I've taken to calling it HAL (hybrid automated loop), though of course it would be much funnier if a certain tangerine diabetic had made that joke, [affects creepily calm synthetic robot voice] "What are you doing Dave? I'm afraid I can't let you eat that biscuit..." etc.

Boxed Tandem tSlim
Staying in its box until I was trained up.

As all this was happening while the healthcare system was in some degree of chaos, and all those buzzwords like 'social distancing' were in full flow I wasn't sure how any kind of switchover was going to be able to happen - but in the end, in classic 2020 style I did my pump training via a video call having had the box of goodies delivered direct to my house.

I had a few weeks with Basal IQ before switching to the smarter Control IQ. Both worked well for me, and each have their own idiosyncracies. I have tried to do as little fiddling as possible, taking an initial 7 days to see how each got on when left to their own devices to try to learn what they are good at, and where they struggle. Also learning how to give them the right information to get the best results.

For those outside the Tandem bubble (seriously 2020? another word you've mangled?!), Basal IQ is Tandem's 'predictive low glucose suspend' algorithm, which stops basal insulin in order to try to reduce risk of hypos. Basal IQ is a little more responsive I feel than Smartguard on my MM640G. In that it can turn on and off more quickly, and doesn't have a minumim duration or enforced gap after it has completed. There was a major irritation for me when running the Basal IQ algorithm in that the tSlim moaned at you if you set a 0% TBR, though ot was more than happy to set one itself. Indeed, the tSlim got very grumpy if a TBR was set that was less than 50% of your lowest basal rate. A degree of warbling which was as unwanted as it was unnecessary.

This irritation was short lived though, as I soon upgraded to Control IQ. One of the nice things about the tSlim is that you can plug it into a computer and upgrade the software on the pump. Which means that if they release fancier, smarter, or even just mildly less irritating versions of the pump software, then you don't have to wait until 4 years have passed to take advantage. All I need now is to find the email address of the person to send my Helpful Suggestions to, for inclusion in the next release 😉

Conclusions

I guess I've been on the tSlim a little short of 6 months now, and I can honestly say that I am really glad I made the switch. I loved the MM640G, but the clunkiness of the Medtronic chassis, and some of the million-presses-UX-interface-tedium was wearing me down. Plus the newer G3 sensors were a bit more flaky and prone to overnight calibration requests for me. There are things about the tSlim I would hope would improve - not least the reservoir filling, which is every bit as fiddly as people say. Their reservoirs really need re-engineering so that the 'white dot' behaves more reliably (tSlim users will know what I mean). 

And what of results? Well I've not really that the nerd-energy for much actual data comparison, but going on gut feeling I would estimate that the tSlim has bumped my TIR (time spent between 4.0 and 9mmol/L) by somewhere between 5% and 15%. What used to be a really good week of results is rapidly becoming pretty normal. Control IQ still needs watching as it often responds a little later than I need, and it's not perhaps as 'hands off' as I was hoping it might be, but Control IQ really nails the little adjustments for me. It struggles with circumstances which are a bit wobblier, but it seems very good at optimising gentle drifts. Overnight with Sleep Mode has been spectacularly good. Almost no alarms, and almost always waking in the 5s to 7s.

Gotta be happy with 28/30 days above 80% TIR

It will be really interesting to see if this has had any kind of effect on my HbA1c, but to be honest, I increasingly find A1c a poor proxy for how I feel my diabetes management is going from month to month. It may still be seen as an important stat as far as research goes, but I'd far rather focus on the ebb, flow, and varying proportions of BG values that lie behind it. But that's another post I'll probably never get around to writing...

Here's hoping for a peaceful, healthy, happy and significantly more stable 2021 for us all.

Posted by on Monday, 15 April 2019

Guest Post: From Dx to X2 (Tandem T:Slim) by Robert S

This is a guest post by Robert S who dropped me a line via FaceTwit as he had been  writing down his 'diabetes story' but didn't have a blog to share it on. Apparently he has been good enough (or mad enough?) to read my ramblings in the past and offered it as a guest post for sharing here. His story echoes much of my own, and I am very interested to read that he has chosen the Tandem T:slim X2 insulin pump out of the current offerings, as that is one I have quietly got my eye on too. Here is Robert's story. Enjoy!

Tandem T:slim X2
My Diabetes Story, by Robert S

I was diagnosed in 1994 at the age of 38, about 10 years after my older sister who had (eventually) been diagnosed at a similar age. I was given a number of very vague, unhelpful leaflets & sent on my way.

I spent the next few years religiously taking insulin as instructed but with pretty poor results.

Diabetes clinics were a trial for me, with many 'must do betters' but precious little advice on how to achieve this. Several times I was mistaken for type 2 & had some very odd conversations. I probably presented as typical type 2, middle aged and overweight, and most people at the clinic were type 2. However they clearly hadn't read my notes which didn't inspire confidence.

I was divorced during this period so I was very much dealing with it on my own.

The internet arrived & eventually I discovered diabetes forums. Wow, what a revelation! There were other people having the same problems as me. A LOT of people! Bad news for them but a great relief that it wasn't just me.

Importantly some of these people were working to improve their diabetes & describing how.

At the time of my diagnosis carbohydrate 'exchanges' seemed to be going out of favour but for me, at least, carb counting was a very vague concept.

The forums prompted me to do the online carb counting course set up by Bournemouth Diabetes & Endocrinology Centre (BDEC). It didn't solve all my problems but for the first time I felt I had a method for moving forward.

By this time I had moved from 'Humulin I' & 'Humulin S' to a basal/bolus regime, which also helped.

My GP surgery contacted me suggesting that they monitor my diabetes now they had a Diabetes Nurse. Being rather disillusioned by my experiences in the clinic system I accepted.

I enjoy programming & wrote software for my phone to record everything & do some basic dosage computations. My HbA1c had never been really terrible, usually in the low 8s (8% or 64mmol/mol, Ed), but I honestly don't know how. Some hard work got it down to the mid 7s (7.5% or 59mmol/mol, Ed).

So the situation had improved somewhat & I felt more in control.

Sadly, another event encouraged my efforts, as my sister died from diabetic complications at the age of 64.

From the beginning hypos were an almost daily event. The worst being overnight. I've always had good hypo warnings, but at night hypos tend to progress further & I would wake up soaked in sweat.

By 2013 though, the overnight hypos seemed to be worse. I discussed it with the diabetes nurse at my GP practice but the best advice was always eat some supper & don't go to bed below 8mmol/L. I was already doing this.

I'd read about Continuous Glucose Monitors (CGMs) which looked very interesting, but were way too expensive for me and, I noted, you still needed to do finger sticks.

Things came to a head on Boxing Day night 2013. I was away staying (alone) in a hotel & I woke up with a hypo around 1:30. Dragged myself out of bed managed to force a some glucose tablets & a biscuit down me & fell asleep. The next thing I knew I was waking curled up in a ball under the duvet, sweating yet shivering to the point where my teeth were chattering continuously. The worst thing was that I couldn't move to do anything about it. Eventually I fell asleep wondering if I'd wake up.

I decided to self fund a Dexcom G4, at least for a while. By the end of January 2014 I was wearing my first CGM. I watched it obsessively. On the second day I attended a graduation ceremony and was offered a glass of Bucks Fizz & a blueberry muffin. I thought I was being sensible & only ate about a third of the muffin & bolused for it. The effect on my blood sugars was fascinating. I watched as the graph went up, & up & up. I don't remember how high but it was an eye opener.

Initially it was more about the alarms which warned me in time to stop low blood sugars. Still annoying at night but I no longer woke up sweating.

I began to learn from the readings. The first big thing I noticed was a fairly consistent dip in my blood sugars around 1:30 to 2:30 in the morning. This made it difficult get my overnight average to a sensible level & went some way to explaining the nocturnal hypos. I tried varying the time that I was injecting my basal (Lantus) moving it from evening to morning, or splitting the dose. Nothing was really satisfactory.

Someone in the DOC (Diabetes Online Community) suggested changing my basal insulin. After chatting to my GP I moved to Levemir. I had a lot of trouble sorting out the dose, being quite worried that I had to take so much more than I had of Lantus. It was a split dosage & gradual adjustments left morning/evening doses very different, but, it was working. I saw some fairly horizontal overnight graphs, something I'd never ever seen before.

This encouraged me & I also made other adjustments; splitting boluses for some meals, not being afraid to do corrections between meals & so on.

Nothing was perfect but I did feel more 'in control'. Things still went wrong but when they did I was confident I could put it right. My HbA1c went below 7% (53mmol/mol) for the first time.

Using online instructions I built a box of electronics which allowed my Dexcom sensor data to be transmitted to my mobile phone. Thanks to #WeAreNotWaiting I set up a NightScout website to display my data.

This was all great, but hard work. I was doing a lot of injections, up to 12 a day. Also absorption of my basal injections was rather erratic, sometimes as I would expect, sometimes not. The best location was my thigh, but despite rotating sites there were problems.

By this time I'd been reading about hybrid closed loop (artificial pancreas) systems. First the DIY systems OpenAPS, Loop, and AndroidAPS, then the first commercial system the Medtronic 670G. This was exciting stuff but it was clear that first you needed to have an insulin pump. I had in fact been offered one about 15 years before but was then horrified at the thought of being permanently connected to the thing.

I decided I would now like to try one. It was not something my GP surgery could sort out so I had to be referred back to the hospital. This proved to be a long process, several months. I still don't know why. Eventually it went through just before Christmas.

By the time I met up with the DSN at the hospital a month or so later I had all but convinced myself I was wasting my time as control was simply too good?

Sure enough the DSN was impressed with my readings but it didn't help my case. I pointed out that I was doing a lot of injections each day. Not relevant.

"How many hypos do you have?"
"Hardly any."
"Yes, but that's with the Dexcom you are funding?" This wonderful lady was on my side & looking to find a way.
"Lots, nasty ones, that's why I bought it"
"That's it! Now let's have a look at the pumps you could have."

What! Really! To be honest I would have accepted some dusty old pump from the back of a drawer..

But when I focused on what she was saying I could barely believe my ears. I'd done a lot of homework on pumps & she was mentioning the Medtronic MM640G & the most advanced, the 'Artificial Pancreas' MM670G.

Then she added the Tandem T:slim X2 to the list. Again I'd read about it but thought it was only available in the USA. Positively it would soon be linked to the Dexcom G6 I was already using. I love my G6 & it seems to compare favourably with the Medtronic sensors. (Not that I had any personal experience of them).

Uniquely the software (firmware) of the X2 can be updated & in the UK will soon include Basal-IQ, a system which automatically suspends insulin if it thinks you will go low. There is also the promise of a full hybrid closed loop option similar to the Medtronic 670G - again an over the internet update.

I made my decision; the T:slim X2. By mid March after a couple of training sessions, I walked out of the hospital attached to my pump. Very exciting & not a little nerve racking!

We had agreed a 30% reduction in the basal dosage compared to my Levemir. A profile was set up.

During the evening it became clear to me that this was still too much & changed to an 80% temporary basal rate (TBR).

My Dexcom woke me about 1:30. I dropped the temporary basal to 75% and had a small snack. Readings got 'stuck' in the low 4s & eventually I ate again and reduced to a 60% TBR.

So not much sleep but at least I was closer to the required dosage. One thing that I kept thinking that night was "How does anyone do this without a CGM??" Presumably they start with a much more conservative dosage.

I had worried about what to do with the pump at night, and it was a problem. Clipping it on my waistband sort of worked but it would slide along to an uncomfortable place or slip off completely. I now have a 'Spibelt' with a pocket for the pump which is much better.

A week in now & I'm doing remarkably well, some days over 90% of my readings have been 'in range' - between 3.9 & 9.9mmol/L. I know this is probably just a 'honeymoon period', having had type 1 for over 20 years I find I'm waiting for reality to reassert itself & everything to go wrong...

The pump itself is a very neat device. It is small & has a nice clear touch screen. If you are used to smartphones then it is easy to use. It seems well made, time will tell.

I've had some practice with temporary basal rates as mentioned but I've also been playing with 'Extended Boluses' a new concept to me, promising, but I need to experiment.

As with all pumps the big advantage is the same as the big disadvantage - namely that it is always connected to you. It's great that I don't have to remember my pens & I won't miss those injections - I stopped counting at about 50,000 several years ago.

A big advantage is that you have a record of every dose. No longer do I have to wonder 'Did I do that or not?'

There's also the precision of boluses & the in built Bolus Wizard (Calculator). I am learning to trust the IOB (Insulin On Board) figure on the pump. Previously I had tended to intervene too soon when blood sugars rose quickly.

I'm told that changing infusion sets on the X2 is slow, but it seems OK to me having never used anything else.

I'm looking forward to improving my settings & the upgrades mentioned above.

For the first time in my diabetic life I feel as though I am 'ahead of the game', and yes, I know I am lucky.

Diabetes has never been so interesting!

By Robert S.

Posted by on Wednesday, 14 November 2018

Frestyle Libre available on prescription. Again.

It's with a certain sense of deja-vu that I mark World Diabetes Day this year with the news that Abbott's Freestyle Libre flash glucose monitor will become available to people with type 1 diabetes in the UK on prescription from April 2019. Cue inevitable Twitter meltdown.

Hang on... haven't we been here before?
Well yes. And no. You may remember me writing a post in September last year on this very subject.

Technically the Libre was made available on prescription on 1st November 2017, "subject to local healthcare economic approval". Prior to that 2017 announcement various Big Health and Diabetes Organisations (such as the Regional Medicines Optimisation Committee, NICE and a collaboration of Diabetes UK, ABCD, JDRF and INPUT) put together helpful documents, guidance and national position statements about what Libre was, who it might be useful for and the evidence to support its use.

What followed was an unholy scrabble of various different CCGs across the UK who either adopted Libre under RMOC criteria, published their own set of rules (which often had bizarre additional requirements that seemed to bear no relation to Libre and its use, such as blood pressure results) or denied access entirely saying that there wasn't enough evidence, or that they didn't like the colour of the packaging or any number of "Whatever we do, let's kick this can as far down the road as we can manage" strategies. And all the while those CCGs in the 'no' camp had meetings and re-reviewed the evidence that had already helpfully been reviewed for them, and invested time (and presumably money) into reinventing all the wheels they could see.

So what emerged was variously described as a 'postcode lottery', 'Libre lotto' and 'bloomin outrage' and across the country people living in the (at the last count) 51 CCGs to have said a big fat NO to prescribing Libre got together and organised themselves to petition, badger and generally make a fuss about it.

Meanwhile, in areas where Libre was more freely prescribed, the early results were overwhelmingly positive. HbA1c's tumbled, and importantly positive effects were seen at all starting points, with significant improvements being seen in those who hardly checked BG at all as well as those regularly checking 6-8 times every day.


And the results didn't begin to tail off after an initial positive surge either. As more data were added, the improvements were sustained and improved further.

Meanwhile the irrepressible, unstoppable force that is Dr Partha Kar was not for taking 'no' for an answer. If the evidence was sufficient for area A, why was it deemed insufficient for area B just down the road? Gentle pressure was applied with an NHS England behatted sledgehammer and a smile. Additionally everyone's second favourite Libre-prescribing-data-muncher Nick Cahm quickly became errant CCG's worst nightmare as he quietly and eloquently sifted through mountains of information to show how utterly nonsensical some of these local decisions were. And Diabetes UK weighed in to support and rally local people in their #fightforflash. The CCGs didn't stand a chance really.

And so today, the biggest of NHS bigwigs Simon Stevens joined in to announce that Libre will be available nationwide under RMOC guidance from April 2019:

“As the NHS prepares to put digital health and technology at the heart of our long term plan for the future, NHS England is taking important action so that regardless of where you live, if you’re a patient with Type 1 diabetes you can reap the benefits of this life improving technology.”

So who exactly will have access?
As far as I am aware this is the guidance (or something quite like it) that will be used to identify appropriate people with diabetes who will benefit from Freestyle Libre going forward:

It is recommended that Freestyle Libre® should only be used for people with Type 1 diabetes, aged four and above, attending specialist Type 1 care using multiple daily injections or insulin pump therapy, who have been assessed by the specialist clinician and deemed to meet one or more of the following:

  1. Patients who undertake intensive monitoring >8 times daily
  2. Those who meet the current NICE criteria for insulin pump therapy (HbA1c >8.5% (69.4mmol/mol) or disabling hypoglycemia as described in NICE TA151) where a successful trial of FreeStyle Libre® may avoid the need for pump therapy.
  3. Those who have recently developed impaired awareness of hypoglycaemia. It is noted that for persistent hypoglycaemia unawareness, NICE recommend continuous glucose monitoring with alarms and Freestyle Libre does currently not have that function.
  4. Frequent admissions (>2 per year) with DKA or hypoglycaemia.
  5. Those who require third parties to carry out monitoring and where conventional blood testing is not possible. In addition, all patients (or carers) must be willing to undertake training in the use of Freestyle Libre® and commit to ongoing regular follow-up and monitoring (including remote follow-up where this is offered). Adjunct blood testing strips should be prescribed according to locally agreed best value guidelines with an expectation that demand/frequency of supply will be reduced.

It will be very interesting to see how this works in practice, and in particular whether this framework allows widespread adoption of Libre2 when that launches in the UK (at the same price as Libre1 apparently), which gives Libre users the option of alerts to prompt scanning when BG rises or falls to particular limits.

Roll on April!

Posted by on Saturday, 13 October 2018

European Launch of the MiniMed 670G - Switzerland

The Medtronic Mothership poised for takeoff
I was chuffed to be invited to join bloggers and diabetes advocates from Belgium, the Netherlands, Switzerland, Sweden, Finland, the UK and other places I have almost certainly forgotten for the Medtronic Diabetes Community Exchange 2018 at Medtronic's European HQ in Tolochenaz, Switzerland.

I was particularly pleased to be invited to walk in the footsteps of the legendary Alison and Tim from Shoot Up or Put Up and to needlessly and completely unnecessarily rekindle the rumours that Medtronic have an entire department dedicated to the drowning of puppies in their relentless pursuit of evil. Rumours which are, of course, entirely untrue. And completely made up by Tim. Or are they?

We arrived on Thursday afternoon and were swiftly transported to the impossibly quaint, beautiful and strangely fragrant 'Chalet Suisse' restaurant where we were treated to a slap-up meal composed of cold meats, pickles and industrial quanities of gently bubbling cheese into which we enthusiastically dunked hunks of white bread. Fluffy white bread, a vat of cheese and a little alcohol. What easier meal could there possibly be for a tableful of pancreas impersonators to contend with? As inevitably happens at these events, people with diabetes quickly feel at ease with each other and conversation flowed to a burbling soundtrack of bleeps and buzzes from various bits of diabetes kit. It was a very lovely evening. Thanks Medtronic!

All those friendly faces and barely a functioning pancreas between them.
European Launch of the MM670G
It was perhaps no surprise that Medtronic had invited us during this particular week - in which their latest hybrid closed-loop insulin pump system launched in Europe. The launch begins with the UK, the Netherlands, Belgium, Sweden, Italy and Slovenia as of 10th October, with Finland and Denmark following hot on our heels next week. I have been using Medtronic pumps for the past 7 years or so, but others around the table used other brands, pods or MDI injections.

Inevitable device timeline pic. No future dates, naturally.
The MiniMed 670G launched in the US in June 2017, and the version launching in Europe is almost exactly the same. If you are new to the snazzy concept of 'sensor augmented pumps' (and why wouldn't you be?) the basic idea is that you combine an insulin pump and CGM (continuous glucose monitor) into one device. At it's simplest, the pump acts as a receiver for the sensor glucose and allows display of current glucose values and can alert the wearer if levels are rising, falling or generally going off kilter. The really clever stuff starts to happen though, when the pump uses an algorithm to act independently on the basis of the received sensor glucose values. On my MM640G I allow Threepio to silently and automatically take action and cut off my basal insulin if my BG is predicted to fall below 3.9 within 30 minutes. This has saved me countless low level hypos whenever I have been able to afford a sensor. If you're interested in the details there's a little animation explaining how this works here.

The MiniMed 670G adds extra oomph to the mix by also having the ability to increase basal insulin where sensor glucose is rising. Gary Scheiner, who wrote 'Think Like a Pancreas' wrote a review of the MM670G after it launched in the US which has a good deal of detail if you are interested, but which also prompted several questions for me.

What I thought I knew
The MiniMed 670G uses two main targets, neither of which can be changed by the user. Overall it aims to direct your glucose value towards 120mg/dl (6.6mmol/L). Where it is taking corrective action for elevated sensor glucose, it aims towards a target of 150mg/dl (8.3mmol/L). These were the launch values in the US, and will be exactly the same for the UK version.

A number of options that experienced pump users might expect to be able to use (temporary basal rates, dual (combo) wave, and square (extended) wave boluses are unavailable in auto mode.

From what I can tell, things like differing basal patterns for weekdays/weekends do not apply in auto mode either.  Nor can you alert the system that you are about to undertake exercise in advance.

In fact there seems to be very little you can adjust and tweak in auto mode aside from insulin:carbohydrate ratios and Duration of Insulin Action. If you are planning to exercise you can temporarily set the pump to aim for the higher target, but that's about it.

All of this may fill you with dread and impending frustration. Or it may elate you with gratitude of being able to hand over responsibility almost entirely.

Users can, of course, use the pump in 'manual' mode whenever they wish. This would give them effectively the same choices/options as the MM640G, but doesn't take advantage of the additional automation on offer.

Is there anything else like this?
No. Well... not regulated, approved and currently commercially available no. But of course the MM670G is not being released into a vacuum. There are other emerging sensor augmented pumps (eg Tandem T:slim) which incorporate predictive low glucose suspend (rather like the MM640G). Alongside which there is a growing community of enthusiastic loopers who have decided #wearenotwaiting and use a variety of homespun, and significantly more tweakable, options. Of course not everyone has the confidence to build their own diabetes device - I am assured that these are no longer cobbled together from bits of string and paperclips, but nevertheless still do require careful configuration, software and in some cases additional DIY hardware. Additionally many loop solutions currently require older out of warranty insulin pumps. This may not be the case for long, nor might OpenAPS and Loop's unregulated status continue, now that Tidepool have committed to developing Loop as a supported, regulated app available for users on a range of in-warranty devices.

What I found out
It's fair to say that I was very enthusiastic about the prospect of the MiniMed 670G about a year ago. But things are moving so fast these days, that this is already beginning to feel like an older model. And as an inveterate fiddler the idea of so few settings being settable by me is a bit... well... unsettling.

What I found very interesting, was the observations Medtronic have made from 3.2 million days of data since its launch in the US. Essentially, they suggest the MiniMed 670G tends to work better in people who don't fiddle and try to come up with their own ways of working around not being able to alter settings. Often people who are new to an insulin pump, who have not already built up a library of hacks, tricks and strategies to bully their pump into doing what they want it to. People who simply give the MM670G the information it requests and heed the alarms, who keep the sensors well calibrated, and who count and supply carb information of meals and then let the pump do its thing, are the ones who tend to get the better results.

I am aware from my own relentless tweakery that at least some of it is frequently down to constant changes in insulin sensitivity and insulin need (and working around times when my pump settings aren't quite right).  I suspect that one of the main reasons behind the lack of tweakability on the MM670G is the closely guarded algorithm. This updates up to 17 different parameters at midnight every single day, based on the previous 24 hour's worth of data along with a rolling average of the previous 5-6 days. Essentially the pump is continually adapting and tailoring itself to you. So those unmovable targets may not seem to be what you have chosen, but the intention of the MiniMed 670G is to keep your BGs as stable as possible to increase your time in range, to reduce glucose variability and to reduce hypoglycaemia to almost nothing. At least... that's the idea. Medtronic are quite upfront that this is the first iteration of this algorithm, based on dozens and dozens of research papers, and that it is intentionally cautious. Other more 'aggressive' versions with greater user control are being strongly hinted at.

A consequence of the 'machine learning' of the pump adapting to you as an individual though, is that it does take a few days of sensor wear for auto mode to become available (48 hours from midnight following sensor start). I'm not exactly sure how that would impact occasional-sensor-users like me, who cannot afford full-time coverage, but it's clear that only a portion of each sensor for me would be auto-able. In theory sensors can be restarted just as they can on earlier enlite-using pumps (sorry Medtronic!), but this newer pump uses Guardian 3 sensor technology, and because the MiniMed 670G has more control over insulin delivery it makes more checks that the sensor data being received is of high enough quality. Without having used it, it's impossible to tell whether it would get twitchy and drop restarted sensors earlier than I am used to.

Case study
It was a delight to meet Rob Howe a Texan ex-pro basketball player and MiniMed 670G user. Tall, slim, athletic, and with that easy, effortless charm that seems to be the gift of so many Americans. He shared his experiences and took part in a Facebook Live broadcast after which we were able to ask more questions.

Rob was an enthusiastic MM670G poster-boy, and having moved from MDI/CGM to an insulin pump with an impressive HbA1c of around 6.2% (44mmol/mol) he was obviously no slouch when it comes to BG juggling.

When asked about changes he had noticed during his year on the pump, one of the most striking was that his regular weekly order of two 1 gallon containers of orange juice he kept in his fridge to treat overnight hypos started to go off before he could use them. They simply weren't needed any more. As a basketball player and all around active type, he also seems to have put the MM670G through its paces exercise-wise, from high intensity BG boosting sprints/weights to longer distance runs of 6-10 miles. Rob was able to keep the pump connected throughout exercise and allowed it to manage his activity, with great success it would seem. Initially Rob said his HbA1c rose a little, perhaps up to the mid 6's (48mmol/mol), but seems to have settled back to the low 6s since. So while the fixed settings on the MM670G algorigthm seem to target an HbA1c of approx 6.7% (50mmol/mol), it looks as though, once again, Your Diabetes May Vary.

What next?
It will be fascinating to see more accounts from real users 'in the wild' across Europe. Several people in the group were about to start with MM670G in November. There was an extended discussion during the end of the afternoon where bloggers raised concerns and questions. There are plans to subtly alter the materials and structure of the MM6xx cases to help avoid those battery compartment cracks (which in turn will mean Medtronic don't have to replace those pumps), plus small alterations to clips, and clip rails. Medtronic are planning a version of the MiniMed 670G which will be able to communicate to phone via Bluetooth. It is notoriously difficult to predict how long it might take to get devices through regulatory approval (and goodness knows what additional chaos Brexit might add to the mix for us in the UK), but reading between the carefully veiled lines it seemed that they were hoping it might be in the next year or two. No promises etc etc. Perhaps even more interestingly... this version of the MM6xx series would have the ability to receive updated software/firmware after distribution. This is something that Medtronic have been inching towards for some time, and could significantly accelerate the takeup of new and better pump versions where the hardware is essentially identical, and it is only the algorithm which needs updating.

One thing is for certain. The rate of change in diabetes devices doesn't look to be slowing down any time soon.

Disclaimer. Medtronic Diabetes invited me to attend the MiniMed 670G European launch in Switzerland. They paid for my economy travel, transfers, accommodation, the welcome meal and lunch at their offices. I wasn't asked or paid to write this blog post or any other social media posts connected to the event. They also included a nifty little Medtronic branded battery power pack thing in a 'welcome' bag. Oh and a pen too.

Posted by on Friday, 5 October 2018

Fight For Flash in Bristol - Diabetes UK

The last remaining island of 'NO!' in the South West
It was great to get together with 30 or so people with diabetes and DUK folks last night in Bristol to consider how to challenge the local behemoth BNSSG CCG (Bristol, North Somerset, South Gloucestershire) to rethink its current 'flat no' position on prescription of Freestyle Libre in the city and surrounds of Bristol.

The event was organised by local legend and all round good egg Sandra Tweddell, who works and campaigns tirelessly to improve the lives, opportunities and experiences of PWD. Sandra called on the wonderful folks from the South West office of Diabetes UK who set up and supported the event.

Bristol's expansive CCG extends to areas around the city, and depending on which of the maps I found online are the most up to date is either one of the last or absolutely the last CCG in the South West to approve Freestyle Libre for prescription. The CCG initially dismissed Libre despite strong support from local specialist diabetes Consultants and DSNs who submitted a very strong case document outlining the potential benefits and cost savings, and national position statements from RMOC, Diabetes UK and the Association of British Clinical Diabetologists.

It is slightly irritating that Bristol suggests 'lack of evidence' as one of their main reasons for denying access to Libre since it was only this year that Bristol finally stopped supplying homeopathic treatment on the NHS. One of the last areas in the country to stop funding a treatment for which there appears to be absolutely no robust scientific evidence at all. Their other, and cynically I might suggest more pressing reason, is a substantial budget deficit. An eyewatering £58 million black (or possibly red?) hole in their finances which is inevitably applying significant pressure on their committees to not pay for anything they absolutely don't have to. It is also striking that while Bristol has internationally recognised specialists and expertise in diabetes research, some of the outcomes for treatment leave a lot to be desired - our record for lower limb amputations ranks as one of the worst in the country, for example. 80% of the UK entire budget spent on diabetes goes on treating complications of living with diabetes. When it goes wrong, we are very expensive to treat.

Dividing into small groups to brainstorm.
The event attracted a wide variety of people, from those diagnosed 40+ years ago, to others with less than 12 months of pancreas impersonation under their belts. After a brief introduction by Diabetes UK's Stefan, we gathered in small groups to brainstorm ideas on 3 different questions: Why do we think the CCG is denying Freestyle Libre in the area? What could we do to convince the CCG to change their minds? and Who could help the campaign?

An absolute torrent of ideas followed. The CCG's position seems fairly entrenched at present and revolves around a perceived lack of evidence, very real financial constraints and perhaps a lack of understanding of the nature of diabetes and how a piece of monitoring technology genuinely can help. Encouragingly discussions inside the CCG are still ongoing (perhaps they are already feeling the pressure) and Diabetes UK is meeting with them later this month. We seem surrounded by people who can help to remove the postcode lottery - several of whom are in positions of significant influence. Everyone's second favourite NHS England Associate National Clinical Director for Diabetes, Partha Kar is making 'gloves off' murmerings where CCGs are resisting Libre and maintaining the postcode lottery, while Keith Vaz and the APPG are mustering Parliamentary support.

As Libre has rolled out across the country and clinicians have begun to share the transformation in quality of life and hard-data outcomes that Libre is bringing to their patients, there surely will come a point where these can no longer be dismissed as merely 'anecdotal'. We were keen to find out exactly what was 'lacking' about the evidence that the CCG had already reviewed, and specifically what sort of evidence they were looking for.

It was great to see the enthusiasm in the room. A real desire to challenge the decision, to clarify the potential benefits to the correct population of PWD (and the potential cost-savings that can result both in the short, medium and long terms). Added to which the annoucement of a CE mark for Abbott's shiny new Libre2 at EASD this week which offers the option of alerts and alarms that many Libre users have been wanting for so long. And the current news seems to be that Libre2 sensors and its reader will cost exactly the same as Libre1.

The meeting closed with commitments to keep up the pressure, write to MPs, involve the local press, liaise with local HCPs and specialists. There are plans to gather more information and case studies of the benefits & cost savings other areas are experiencing (particularly where these include substantial short-term savings eg for hypoglycaemia and DKA admissions). There was also a genuine desire to try to get in front of the CCG in person and/or as a group. I may have accidentally suggested going mob-handed to the CCG AGM or a similar public meeting dressed as Jelly Babies. A Flashmob, if you will.

Watch this space.

Posted by on Tuesday, 15 May 2018

Feeling lucky at the Houses of Parliament.

Abbott's Jared Watkin, Robert Courts MP for Witney,
Lord O'Shaughnessy and some scruffbag on the end.
A week ago today I had the unexpected honour of being invited to the Houses of Parliament to a Parliamentary Reception on 'Innovation in Diabetes Care' hosted by Robert Courts, MP for Witney. Not your usual Tuesday.

Not only that, I had been asked to give a brief chat about the impact of technology on diabetes self-management.

The event was put together by everyone's second favourite flash glucose device manufacturer Abbott Diabetes Care, and it was great to bump into some familiar faces, including Diabetes UK's Chris Askew, as well as lovely folks from the Health Innovation Network, and various other luminaries, civil and public servants interested in healthcare. It's a bit unnerving to asked to speak to a room where speeches and introductions have begun "my lords, ladies and gentlemen" without that just being a jokey thing to say.

There was a buzz at the reception about access to diabetes technology, its importance and how access can be improved and made more consistent across the UK. Naturally there was mention of the emerging Libre accessibility map, but this was about more than just that one device. It was about recognising how far diabetes care has come, and the potential improvements to outcomes that have become possible.

Robert Courts, who is the MP for the constituency which is home to Abbott's shiny manufacturing plant spoke first, before handing over to Jared Watkin, the (surprisingly Welsh) president of Abbott Diabetes Care. Lord O'Shaughnessy Parliamentary Under-Secretary of State for Health later spoke about the Government's Life Sciences Industrial Strategy and promoting swifter access to breakthrough technologies.

For my own small part I opted for three 'I feel lucky's.

I feel lucky I wasn't diagnosed 70 years earlier. I was diagnosed in 1991, and it was only 70 years earlier than that good old Banting and Best made their breakthrough discovery. Now we all know that living with type 1 diabetes is fraught with tales of lost feet, fried eyes and defunct kidneys, but it really wasn't all that long ago that us pancreatically challenged types really were not expected to last very long at all.

I feel lucky that it's 'only' diabetes. Now this, of course, is one of those phrases that you are only allowed to say if you have diabetes yourself (and even then only if you have the specific type to which you are referring). Having said that, and for all the looming spectres of physical and mental long-term complications, and the never-ending infuriating drudgery of the whole silly game I have often found myself musing that if I had been taken into a side room at the Drs on that fateful day 27 years ago and been presented with a table laid out with all manner of options, "We are sorry Mike, your number has come up and you have to have a long-term condition. Here they all are, with their pros and cons - you just have to pick one." I half wonder whether type 1 diabetes wouldn't have been a pretty good choice. You can eat pretty much what you like, within reason. You can do almost anything you want to. It doesn't stop you doing very many things that you might want to. You can actively work towards improving your situation and try to avoid the looming nasties. You can run a business. Run a marathon. Raise a family. And many people live long and healthy lives alongside it.

And I realise that much of my optimism stems from the advances in technology that I have seen over the years, and I'm thinking of technology in the broadest sense - gadgets yes like monitoring, insulins and insulin delivery, but also education and support networks.

I feel lucky that there has never been a better time to be diagnosed with type 1 diabetes. Which is probably a good thing because ever increasing numbers are joining our happy band. Even our own PM couldn't resist getting in on the fun. But the improvements in the technology and understanding we have available to us (at least available in theory) make the possibility of normal blood glucose outcomes tantalisingly close. And when you consider the emerging semi-automation of insulin delivery technologies alongside continuous glucose data, then the burden of self-management looks likely to reduce in the coming years.

I see access to technology (alongside education and support) as key in shifting the balance between the 80% of the diabetes budget currently spent on treating diabetes complications and the 20% spent on trying to keep people well. We may not be able to get those proportions to swap around, but I'd love to get things nearer 50:50 - hopefully by significantly reducing the financial and personal cost that comes when people with diabetes really struggle.

Oh and if all else fails, 'the cure' is only 10 years away too. Isn't that right Dave?

Disclaimer. Abbott Diabetes invited me to share my experiences of diabetes technology at the Parliamentary Reception, paid my travel expenses and offered a modest honorarium for my time at the event. They also laid on some tasty sandwiches and a very nice custard tart which I miraculously managed to carb-guess and SWAG bolus. I wasn't asked or paid to write this post or asked to mention any Abbott products in anything I said, which is lucky really because I pretty much didn't.

Posted by on Wednesday, 13 September 2017

Libre available on NHS - big news and bigger caveats

Last night the rumour mill reached fever pitch as Non Disclosure Agreements were stretched to their very limits. And this morning the Twitterweb was a-buzz with the news that Abbott's Freestyle Libre flash glucose monitor is to become available on the NHS from 1st November*. JDRF issued this nifty press release and everyone's second-favourite cat-loving pyjama-wearing T1 ex-schoolteacher and all-round good egg, Adrian Long, was even glimpsed on Sky News in the early morning undertaking some top Libre punditry and sharing his love of 'Libs'.

* subject to local healthcare economic approval, CCG friendliness, moon in jupiter, blah blah blah.

Of course, no sooner had the long-awaited announcement been made than people began to get a bit sniffy about it, or unbelievably optimistic - depending on their frame of mind. Either Libres were about to be handed out to everyone immediately, whether they wanted them or not; or it was going to be a postcode lottery / the end of CGM funding / a complete disaster.

The official announcement from Abbott covers the whole of the UK, including Scotland, Wales and Northern Ireland. Freestyle Libre will be on the 'drug tariff'. Which means that it will be able to be prescribed, and reimbursed by the NHS.

BUT (and depending on your point of view this might be a small niggle, or a deal breaker), this is subject to local health economy approval.

It's an important step, but it might not be the end
I think I probably come down more on the side of 'wildly optimistic' about the announcement. But the 'local health economy' / local clinical commissioning group (CCG) approval thing is a bit of a worry. Even the JDRF announcement is rather cautious, stressing how important it is that the technology actually does end up reaching people. There may still be some work to do in your area to encourage the bean counters to play fair.

Balance of costs
The cost to the NHS of one Libre sensor is going to be £35. For people using intensive insulin therapy who might be using 8 or more finger stick test strips a day, the costs more or less balance out. Assuming an average-ish strip cost to the NHS of £14.50/pot it costs the NHS about £2.32 a day for 8 strips, versus £2.50/day for Libre sensors lasting 14 days where you can be checking 15, 20, 30 times a day or more. I am reminded of the real-world data that Abbott shared recently. In general, across all their users, the more people used Libre, the better their results. Fewer hypos, fewer highs, more time in range and a lower predicted HbA1c.

Even if you are not prepared to take on the heaving behemoth that is your local CCG and try to turn them around to the idea, I can certainly imagine myself having an interesting conversation with my GP (who, of course, runs their own business) about exchanging my strips for sensors for all the added benefits that gives me. It may be that as part of that negotiation I suggest paying for my own strips for DVLA and other occasional requirements. The cost analysis undertaken by NICE for T1 demonstrates that 8-10 strips a day can be cost effective (more BG information is associated with better BG outcomes and reduced complication risk). There may be niggling details and rules about 'local formulary', but it's certainly a conversation I'd be interested in having with my GP if the local CCG drag their heels (as they have been known to do in my area).

Getting your GP and/or hospital clinic on-side and banging the table for you is a good plan too. Speak to them and get them to apply pressure to the CCG to ensure readers and sensors are listed in the local formulary (which is located at Hogwarts just down the corridor from potions and defense against the dark arts).

But what about 'proper' CGM?
Some people have worried that all these funds getting diverted to Libre will spell the end of CGM funding. Personally I don't see that happening. CGM is currently only weakly recommended in national guidance for people who have significant problems with recurrent hypoglycaemia and have lost all or almost all of their hypo warning signs. The submissions to the NHS for approval were very clear that while Libre can really help some people reduce their exposure to hypoglycaemia with extra information, they are not a substitute for CGM alarms/sensor augmented pump for those with no awareness.

Diabetes UK have put together a position statement on Flash Glucose monitoring which I was pleased to be involved in, and which I think clarifies many of the issues about the Freestyle Libre. What it is good for and who can benefit from it. Thankfully it involves people with Type 1 and Type 2 diabetes - and actually I think should be applied to anyone with any of the many types of diabetes who are intensively using insulin. The recommendations on page 4 are very interesting.

Of course some people have been able to carefully negotiate the fiery hoops to secure full or partial NHS funding for CGM in their own particular case. I'm not sure I see the availability of Libre as affecting the clinical reasons which led to their funding being granted - unless they wanted to swap of course! Freestyle Libre is not a CGM, and does not issue alarms. If those alerts are important to you, then CGM is the better option. But for others the lack of 'alarm fatigue' is a positive benefit of Libre.

Onward and upward
I am really encouraged by this announcement. It's been a long time coming and a lot of work has been done behind the scenes to get to this point. Huge thanks to Lesley and Melissa at INPUT, the team at JDRF and Diabetes UK, and not forgetting Dr Partha Kar in getting us this far.

I am absolutely convinced that Freestyle Libre has a huge potential to help thousands of people who are quietly struggling with their diabetes management. Not in extreme enough need with frequent A&E visits to attract CGM funding, but just keeping going not knowing what they don't know about their BG fluctuations. I really hope the technology can be made available so that those quiet strugglers can go from doing OK to doing really well. Can reduce their long-term complication risk and improve their quality of life.

Posted by on Monday, 15 May 2017

Medtronic Guardian Connect Review - iPhone CGM in the cloud

Guardian Connect on iPhone, Guardian 2 on MM640G
and Contour Next Link 2.4
As some of you may know I've been lucky enough to be wearing Medtronic's new box of CGM tricks recently, and with nearly 4 weeks' wear under my belt and a few more days to go, it seems about time to post my thoughts about this new addition to the list of CGM options.

Ground rules
As I have been reflecting on my time using the Guardian Connect, a few things have stood out to me from the start. The first is that this is now the third continuous sensor system that I have tried. My first experience was Abbott's Libre flash glucose monitor (not strictly a CGM) and later, the MiniMed 640G sensor-augmented pump system which I trialled for 9 weeks in 2015. I mention this, because I think it has a significant effect on how I have responded to the Medtronic Guardian Connect. I am now no longer comparing 'no continuous data' to 'continuous data' which is, in itself, a huge change. Essentially you can take for granted that I am enjoying all the 'usual' benefits of access to continuous data - the ability to glance at your glucose level whenever you want to; overnight basal test type traces every morning, and trend and 'direction of travel' indicators. So what you get here is more me comparing the tiny details in user experience between the various systems, rather than being swept along by the benefits of CGM itself. I'm not sure if that makes this more or less helpful for anyone reading... but there it is.

Initial bewilderment
I don't know if you know anything about the Guardian Connect as you start reading this, or any other Medtronic diabetes technology for that matter - I mean why would you? But me... I'm on the inside, and that perhaps gave me certain expectations. I first chose a Medtronic Paradigm Veo which tantalisingly offered a 'low glucose suspend' if paired with the sensors that I never quite managed to afford. When I subsequently trialled the MM640G with it's souped-up 'predictive low glucose suspend' I think it's fair to say that for me, the results were extraordinary. Finally a piece of diabetes technology was actually proactively helping me out - dodging hypos automatically while I was blissfully unaware. So when I was first invited to trial the Guardian Connect I assumed that, of course, it would integrate with Medtronic pumps, SmartGuard and all the rest... Well... it doesn't.

So... CGM on iPhone... CGM in the cloud... sounds great! But what do you mean it doesn't link with SmartGuard? - I mean, wait... what?!
What I knew from the outset, was that the Medtronic Guardian Connect was a CGM that displayed sensor glucose readings on your iPhone, which sounds cool. And that it was Medtronic's 'CGM in the cloud' solution, which has very much been the buzzy new thing to have for a year or two. But I confess it completely threw me that this new CGM would not also communicate with my pump.

A new product line that explicitly doesn't offer the market-leading benefits of other devices in the same stable, while simultaneously offering all that trendy cloud-share-ness. Medtronic giveth, and they taketh away. Of course, Medtronic are keen to point out that the Guardian Connect was always designed as a standalone CGM (Medtronic have had a standalone Guardian CGM line for as long as I can remember). They say that this technology is intended for users of other pump brands, or people on multiple daily injections (MDI). Well... maybe. But I still find myself wondering whether a company would take this sort of decision if we were not living in a global marketplace with such complex approval mechanisms and timelines in different locations.

In a way I can sort of understand it from a technical perspective - my MM640G communicates on a completely different frequency to the bluetooth on my iPhone, so a transmitter would have to be able to send information to both devices. Would that increase transmitter size? I don't know - to be honest, I'm not really sure I care. All I know was that finding out that all the Guardian Connect iPhone-displaying-cloud-sharing juiciness came at the expense of SmartGuard was a real kicker.

The disappointment was particularly sharp when I discovered that people in the US have access to MiniMed Connect, which does link a MM530G, essentially a Veo with low glucose suspend, and transmits CGM to an app on iPhone or Android. Apparently MiniMed Connect is soon promised for the MM670G too - a newer pump than mine and not available in the UK. But all things? Approved in all markets? Available in all countries? Apparently not.

CGM displayed on your iPhone? Brilliant!
Having said all that, the idea of getting your sensor glucose sent to your iPhone is very appealing. I have very limited pocket space, and having to avoid scouring my phone screen to oblivion I need to keep keys and loose change in one pocket and my phone in another. So when using a Libre, with its separate reader, I have to squish reader and phone in the same pocket, and keep the reader in a little fluffy sock to keep them apart. Yes, you are right I am *such* a nerd. In short, having to carry a separate reader is a bit of a bind and the idea that I can use something I always carry with me anyway is hugely appealing.

Users of robot, rather than fruit-based smartphones may be wondering at this point whether Guardian Connect is available for Android? Well, at the time of writing, it isn't. And unfortunately I have no idea when, or if, an Android release might be available.

CGM in the cloud
The conspicuously 'on-trend' facility of the Guardian Connect is the way that it links to your Carelink account and can use a small slice of your phone's data connectivity to seamlessly upload your CGM data in the background. This gives you the opportunity of sharing your live CGM data with, for example, a partner, family member or housemate. This facility is particularly welcomed by parents of children with diabetes, who are able to keep an eye on things while their youngsters enjoy freedom to roam. Additionally Carelink allows you to set up text alerts, which will send an emergency message to a number or set of numbers if you do not respond to a low glucose alert. A potential lifesaver.

I think it is fair to say that personally I am not keen on Medtronic's Carelink platform. Particularly in its difficult current phase which is fraught with warnings of incompatibility if you dare to use current and up-to-date software. Medtronic promise that they are looking into upgrading their aging software, but evidence of progress or timeline remains frustratingly absent, aside from the recent release of Carelink Pro reports for everyone. The upshot of this lack of updatedness is that if you attempt to log-in to Carelink via iPhone you are greeted with a warning screen. However once you clear the warning, the live CGM data shows without problem. This easy access to sharing sensor glucose information has potentially powerful safety implications and would be a major encouragement, much as it is with Dexcom's Share, and the more homespun Nightscout options.

Getting set up
Before getting up close and personal with the new CGM technology, the first order of business was to download the Medtronic Guardian app from the App Store and hook it into my Medtronic Carelink account. For me, the next phase glamorously took place at the Diabeter clinic in Rotterdam, and involved pairing the Guardian Connect transmitter via Bluetooth to my iPhone. Screens in the Guardian app walked you through the pairing process, and an internet connection was required for the set-up. Once the ground work had been done it was simply a matter of inserting the Enlite sensor and waiting around 2 hours for the sensor to start-up. The Guardian Connect uses the same Enlite sensors as the MM640G system, but uses a completely different transmitter in order to communicate with your iPhone, iPad or iPod Touch.

Calibration 
Once the sensor has warmed-up you are prompted for a fingerstick calibration, which you enter into the app by pressing the blood-droplet 'calibration marker' top-right. This then shows a green circle around it which begins to count down, handily indicating the approximate amount of time before the next calibration is due. The precise timing being shown on the calibration entry screen itself. The calibration follows the familiar Enlite pattern of 2-6-12 hours after insertion and then approximately 12 hourly after that. The Guardian Connect also has the ability to request an additional calibration if it worries that things might be drifting slightly. My habit with Medtronic CGM has been to calibrate immediately before most meals (as long as they are not expected to be horrendously spiky ones). I find that 4 calibrations a day usually keeps an Enlite tracking very well for me. The usual guidance on calibration applies here - you should choose a time where, ideally, BG is within your target range, has been stable for 30 minutes or more and is expected to remain stable for the next 30 minutes. Avoiding calibrating when the Guardian app is showing up or down arrows really helps to keep the calibrations true. One nice thing about calibrations with Guardian Connect is that they are significantly faster than when I have used Enlite sensors with my pump. Connect calibrations are done and dusted within 5 minutes, while it can take 10-15 for my pump to finish calibrating.

Once or twice over my time with the Guardian Connect I have been prompted for an additional calibration overnight, which was initially confusing as I knew I had calibrated at around 11pm so should have been OK until morning. I suspect these were down to a less than ideal calibration earlier, eg one with BG moving or above target range.

A note for non-CGM users 
It is probably worth noting at this point for anyone reading who is considering using CGM for the first time the whole 'accuracy' question. People spend endless hours debating relative accuracies with CGM devices, and stressing or worrying if fingerstick and BG results are not identical all the time. In many ways, this is largely a waste of effort because a continuous sensor and plasma-calibrated blood glucose test strip are measuring completely different things - so they will never, can never show the same results all the time. It takes a while for glucose concentration in the fluid between tissue cells (that sensors measure) to come into line with capillary blood glucose. The differences are most noticeable when blood glucose is changing rapidly, and I particularly notice the lag when waiting for sensor glucose to show recovery after a dip into hypoglycaemia where the sensor may be 10 minutes or more behind 'now'. So you are well advised to decide to be fairly relaxed about any differences you see - providing, of course, that in general the information is within usable parameters.

For interest I am intending to give a suggestion of how I have found the tracking of Enlite sensors matches with fingerstick BG by taking a week of paired calibration readings. I've not got time to do that today, but I will add it here as soon as I can. My general feeling is that tracking between Enlites and fingersticks with the Guardian Connect is really very good indeed. And I trust it pretty much all the time. It's interesting to note how my frequency of fingerstick testing has fallen away while wearing sensors. Many days only checking fingersticks before meals, before bed, and before driving.

Update: Calibration and tracking vs Contour Next Link 2.4 
As promised I am editing this post to include some pairs of results between Enlite sensors on the Guardian Connect and my fingerstick BG meter (the Contour Next Link 2.4 USB that connects to my pump). Out of interest I have also done a comparison between the 'calibration' pairs for one of the sensors I have been using with my MM640G using the Guardian 2 transmitter - just because I was curious to see if there was any difference. Essentially I have looked at all the fingerstick BGs over the official 6 day life of the sensor that I used for calibration and compared them to the sensor glucose reading at the time. I should stress that this is not very scientific, and mostly for my own interest. The data set is pretty small (29 pairs for the Guardian Connect and 26 pairs for the MM640G). For what they are worth, here they are:

Medtronic Guardian Connect / Enlite results compared to Contour Next Link BG meter
BG meterSensorAvg +/- %
(against BG meter reading)
Avg +/- mmol/L
(against BG meter reading)
Average8.4mmol/L8.3mmol/L7.8%0.6
SD2.82.55.7%0.4
Distribution of readings
Number of readings where sensor higher1138%
Number of readings where sensor lower1655%
Number of readings equal310%
Number of readings within 0.5mmol/L1345%

Medtronic MM640G / Guardian 2 / Enlite results compared to Contour Next Link BG meter
BG meterSensorAvg +/- %
(against BG meter reading)
Avg +/- mmol/L
(against BG meter reading)
Average7.2mmol/L7.2mmol/L7.7%0.6
SD1.51.15.7%0.5
Distribution of readings
Number of readings where sensor higher1246%
Number of readings where sensor lower1142%
Number of readings equal415%
Number of readings within 0.5mmol/L1350%

My feeling is that these results are pretty much exactly the same between the two systems, which is reassuring, especially given the more varied results I was having on the days with the Guardian Connect with a higher average and wider SD (range of results). The MARD of less than 8% difference is above the expected performance of these sensors - I have always thought I must have lucky 'body chemistry' or whatever it is that means the sensors work better for some people than others. Effectively, it shows me that most of the time either of these systems will give me a result somewhere around 0.2-1.0mmol/L different from a fingerstick BG measurement (with potentially larger differences if my BG is moving rapidly, obviously). Around half the time, where my BG is just pottering along, sensor glucose and BG fingerstick are going to be less than 0.5mmol/L apart. And that is a level of accuracy I find easy to trust, and extremely useful in informing my diabetes management day to day.


Inside the app - traces, alerts and arrows
As a full CGM, the Guardian Connect offers both a rolling view of sensor glucose and audible/vibrate alerts if sensor glucose is, or is predicted to be, outside of a range you set. Today's sensor values are plotted as a graph and are viewable in 3hr, 6hr, 12hr and 24hr versions which each allow you to swipe back through previous time periods. Holding a finger over the graph reveals a scrolling pop-up of the value at that time. Additionally you can open the 'Now' menu to look back through previous day's sensor data.

Current sensor glucose is displayed above the graph, along with the menu and calibration icons. Where sensor glucose is changing more rapidly single, double or triple up or down arrows appear alongside the current sensor glucose reading.

Helpfully, when the sensor is coming close to expiry, or is running short of battery, you are alerted by icons on the main screen. Alternatively, you can always view the current details by looking in the menu screen.

The Guardian app also allows you to log insulin doses, carbs, blood glucose readings, activity or to make notes. The interface for adding and viewing each of these is pleasingly slick, but unfortunately you are required to log each value on a separate screen which would make regular use of them rather tiresome so I can't really see myself manually logging much additional detail using the app. The ability to add notes to provide context to what you are doing could be very handy though.

I was really pleased at the configurability of the alerts with the Connect. You can set both high and low alerts, along with additional alerts which are triggered anything from 10 minutes to 1 hour before your hard limit is expected to be reached if current sensor glucose trajectory continues. You can also set alerts where glucose is falling or rising particularly quickly. Snooze time allows you to customise how frequently you will be reminded of an alert condition - high and rise alert reminders can be set between 5 minutes and 3 hours while low and fall alerts can be set between 5 minutes and 1 hour. This probably all sounds needlessly confusing and granular in detail, but one of the challenges with CGM is to get good usable prompts without feeling nagged all the time, which makes the ability to precisely tailor both the mixture of alerts and their nag-ability really important.

You are also able to set an optional alert as a reminder that calibration is coming close to being due (rushing out of the house with no BG meter when a calibration comes due could make sensor glucose unavailable).

Not only that, but any and all of these alerts can be silenced at once with a single press on the iPhone's 'Control Centre' - more on that a little later.

Widget and app frustrations
Enabling Guardian Connect in the Notification centre can give you access to both alerts and a sensor glucose 'widget' on your phone's Lock Screen. Inexplicably though, the widget for a mmol/L Guardian Connect displays sensor glucose in mg/dl in the Lock Screen widget. Thankfully, as an app, this *should* be relatively easy for Medtronic to fix, but it still looks a little messy. Until the fix, users will just have to fall back on the, 'divide by 10, divide by 2, add 10%' mental acrobatics - unless their 18x table is reeeeeally good. As an example... 250 divide by 10 is 25. Half of 25 is 12.5 and then add 10% which makes 250mg/dl roughly 13.7mmol/L. Inside the app, alert states are shown by use of a coloured overlay panel.

Another frustration I had with the app, for all its smooth animation and solid build, was the total lack of any data analysis. I'm not sure whether this is something Medtronic have slated to add in future releases, but it seemed to me to be a significant missed opportunity not to have some sort of 7, 14, 30, 90 day sensor data overviews and number crunching. Or better still a pinch of Ambulatory Glucose Profiling to help make sense of that avalanche of data.

Enough with the interminable detail already - tell us what it was like to actually use!
Yes, sorry about that. Where were we...

Well... it's interesting. And actually I have been rather surprised by the experience. I think the only way to get my head around it is to list it as a series of pros and cons.

Pro - Less to carry, and very unobtrusive
Not having to carry an extra, separate reader has major benefits in terms of pocket space. We are used to carrying phones. We are used to glancing at them. No one would have any idea that you were interacting with your diabetes, even if you respond to or check an alert. Because that is what people do all the time in the modern world. There are a variety of tones used by the app, which indicate different things going on even before you get the phone out of your pocket. I kinda wish they had made the high and low alert tones slightly more varied. They do step up and down, but there is only around a semitone between the beginning and end and a quarter tone in between those, which all happens very rapidly. Occasionally I have heard the tone, but been unable to work out whether it was rising or falling. Of course it's not a real problem as it's only a glance at the screen to confirm - but I would have preferred that fraction of a second heads-up especially in circumstances where I might not be able to get my phone out for a minute or two.

Con - Now your phone is something else
Using the Guardian Connect has required me to make some adjustments in the way I use my phone - because now it is also my CGM receiver. I generally have my phone on silent, but I soon found that the single 'buzz' vibration alerts were too easy to miss, so I needed to put my phone's sounds on. Remember the single control centre command I mentioned to (helpfully) silence all CGM alerts if ever you needed to? It's the iPhone's 'Do not disturb' setting, which I have had running automatically overnight for several years. This prevented alerts sounding for ovenight hypoglycaemia, so I've had to de-activate its schedule and now activate it manually if I need to be notification-free for a time.


Pro - Phone battery life still reasonable
I am used to getting decent battery life out of my iPhones. Something like 3 days from a single charge - I suspect this makes me something of a rarity. I don't have a lot of push data notifications going on, and I deliberately restrict many of the usual battery hogs like background app refresh and screen brightness. I was a little concerned that the drip feed of continual data might suck all the life out of my battery, but while Guardian Connect has added a not insignificant demand on battery life I am still getting at least a full 2 days out of a single charge.

Con - battery charging
Of course, the flip side is that if you do run out of battery, it's no longer just your Twitter feed that you are missing - its your CGM and alerts too. And if your phone needs charging during the day, for all the time it's connected to the power socket you need to stay within about 9 feet of it to receive CGM alerts. This makes overnight phone charging a good basic approach.

Pro - gap filling
There have been times when my own peculiar charge cycle has got the better of me, and I've had to leave my phone charging on the side while I leave the room (or even the house) to do whatever. The neat trick of the Guardian Connect is that it stores several hours of data in the sensor, so that when you finally reconnect app and sensor the gaps are automatically filled in and your data remains intact. You don't get the missing alerts, of course. But at least you can look back over what has been going on while you've been away from your phone.

Con - Alert volume
Most of the time, when inside, the alerts are plenty loud enough. But the world is a busy, noisy place, and all too easily when walking outside I have missed both noise and vibrate alert. As a consequence I have tended to use the Guardian Connect a little like a Libre when out and about. Making sure I check it relatively frequently and not assuming the audible alerts would be able to cut through the hubbub. Sadly there's no way of making only the Connect alerts loud and leaving all your others at a quieter level, so it's a bit 'all or nothing'. I suppose as a fallback you could set a shorter alert snooze time so that you would get more repeated reminders of missed alerts.

Conclusions
I've not run any kind of analysis of BG numbers or hypoglycaemia frequency between Libre, MM640G/Smartguard and fingerstick-only as part of this review - quite frankly if you've made it this far I think you deserve a medal! I may try to find time to take a look at that in coming weeks with the data that are now safely stored in Carelink.

There is an awful lot to like about the Medtronic Guardian Connect. Despite my initial bewilderment, as a standalone product I think it sits very well among the current market and there is much to recommend it.

Medtronic get a bit twitchy at the idea of people who are trialling their kit restarting sensors, but having self-funded the same Enlites that this system uses since January I have found that I can get 12-14 days out of those with little if any apparent loss of performance. For anyone considering self-funding, the ability to restart to extend sensor life can be a make or break factor and I have no reason to believe that the Guardian Connect would behave differently to the Enlite's I've been using with my MM640G. Having said that I may just have lucky body-chemistry as I know from other user-groups that some people struggle to get more than 6 days out of an Enlite - so as ever YDMV.

My few weeks with the Medtronic Guardian Connect have given me very solid CGM performance, brilliantly flexible and tailorable alerts and while lacking the automation of Smartguard I get the feeling that the Guardian Connect has really helped me to keep my BGs in range, with very few hypos, and hardly any highs.

I've enjoyed using the system, though for a number of reasons I don't think it's one for me long-term.  I hope you've found this review interesting, please share your thoughts below.

Disclaimer: Medtronic offered me a trial of the Guardian Connect on loan with enough sensors to last 30 days. I have not been asked to write this or any other post about it, and have tried to accurately portray my likes and dislikes of the system. If I had thought it was utter rubbish I would have said so.