More info on using CGMs (continuous glucose monitors) to see what your diet and exercise does to your blood sugar levels.

[PMRpro]

This cropped up in a daily reading list and after the discussion about CGMs a few weeks ago I thought you might like to read it too

medscape.com/viewarticle/99...

[Blearyeyed]

Thanks for that very interesting.As I said previously, my husband has had a Libre device for sometime .

From experience, we would now say , these monitors are useful and convenient but certainly not perfect , and, to be frank, if you have Type 1 or severe Type2 Diabetes , don't be persuaded to give up on the glucose strip test device or to rely on that alone . The test yourself device is the only really accurate measurement at a specific time.

The CGMs lag behind , about 15-20 mins to your actual levels , so you need to be careful.

If they register you as low and notify you , your strip reading will be lower than the one on the device so you can't judge how long you have to get a snack in the same way as you would with strip tests kit. A reading of 4 , which may make you think you don't have to react and have time to get home or find food is more likely to be 3.5 or much lower which actually requires quicker attention before you become dizzy or suffer symptoms which could cause a hypo.

Also, if it registers that you are high , your actual level by the time of notification could either be much higher or back to normal depending on whether you had been exercising or had already taken your insulin.

The also can cause confusion and over eating when you first get out of bed , because they may not you are low as you get up , but that is partly because the body has been static for a number of hours , you level could be much higher as you get out of bed and get dressed because the return of activity causes the blood sugar to rise naturally. It is better to strip test just before you prepare breakfast in the normal way.

They often come unstuck and you have a limit on prescribed arm patches so you do benefit from ordering waterproof patches to put over them to secure them in place. You can't just pop them back in once they fall out the device will stop working.

One episode that my husband only experienced a few days after the last post was more concerning to us because it hadn't occurred before, but would have had very serious implications if we hadn't got used to checking his results with a strip test which GPs don't always recommend for you to do.

He received notifications that he was very high and he had symptoms , so as a Type 1 Diabetic the home emergency treatment would be to take extra insulin.

Luckily we are in the habit of checking , it turned out that his glucose was very low instead and if we'd followed the CGM notification without the check he would have required an ambulance. An hour later the device beeped stating a needle fault. We did not realise that this type of error could happen , the device recording glucose problems as though normally working before noticing that it had a fault and was producing faulty readings .

That's not to say a CGM isn't handy as a daily record of glucose levels but they certainly aren't infallible, and I certainly wouldn't rely on them to help me make a choice on taking glucose or insulin without verifying it first in the normal way with the instant strip test monitor if I was a Type1 Diabetic or had severe glucose issues.

Just worth knowing I think before you make your choices , take care , Bee

[PMRpro Ambassador in reply to Blearyeyed]

That is concerning - I assume you have reported the various problems? It sounds as if your real-life testing may be better than the company's was!

[Blearyeyed in reply to PMRpro]

Yes , we have reported it , we also told the GP about the recent issue , which they were concerned about and are going to inform the surgery patients that use them to remember to do a pinprick test after a notification.I think they are probably great for guidance on a persons daily glucose us and do probably help people improve their diet , portion size or choices while doing exercise.

But only in the same way as a Smart watch is helpful for monitoring somebody's activity , step count and heart rate , but that they can't be relied upon for blood pressure or O2 readings for medically accurate results in a person of varying ages or with health issues.

You can't rely upon them to make a decision on your immediate medical needs , all they should be used for is to give a patient a warning that you need to test yourself , and I think this warning needs to go out to all GPs and hospitals that beginning to use them.

[Koalajane]

my daughter told me she had been to an innovators talk where a ring has been invented that tests blood glucose. I told her I have no faith in things that don’t even connect with blood!

I think that CGMs can be good but see the warnings that finger prick testing should be done before action. Glucose monitors are only handed out by doctors to type 2s who are on certain meds that can cause a hypo or on insulin. So I can’t see the likelihood of them handing out CGMs to many as they are expensive items. It may happen but not yet!

[PMRpro Ambassador in reply to Koalajane]

There has been a lot of discussion on the forum with some toying with the idea of getting a CGM themselves to study the effect of pred on blood sugar levels relating to various foods.

[Koalajane]

I believe you can have a free trial but it is the sensors that are expensive as are the test strips for glucose monitors

[Blearyeyed in reply to Koalajane]

The glucose test strips aren't that expensive , and if you require a glucose test kit you will get those prescribed .The CGM sensors are incredibly expensive, which is why you get a very tight limit each month even as a prescribed element , about £50 per sensor. Which makes it quite complex in trying to get prescribed replacements when they have a habit of dropping off.

They know they don't stick properly now which is why the suggest extra skin guards plasters to wear over the sensor but these themselves add an extra £10 a month to the cost and you do have to buy those yourself.

[Koalajane in reply to Blearyeyed]

The test strips for my meter are about £10:or more for 50 strips, so do not last long especially when you get error messages. A lot of type 2s end up funding their own because doctors will only put them on prescription if you are on insulin or on a med that can cause a hypo like gliclazide. I feel strongly that all type 2s should be prescribed them if they want to as it helps to find which food spikes your sugars

[Blearyeyed in reply to Koalajane]

Totally agree, especially if they think you require a strip test monitor , they should also think it's medically important enough to prescribe the strips for you to test regularly.I know the rules on this are different in Wales to England , I know a lot of Type 2 diet managed people who got the CGM and the strips for their monitor for free .

My friend is in England and diet maintained Type 2 , and obviously needs to pay for the prescription because of her age and work status but her GP writes a prescription for 100 strips ( 2 boxes per script) for her , so it does work out cheaper.

You can always try to get individual patient funding for them as well , a bit of a long process and your GP needs to be willing to be proactive but then you can get them funded too.

It seems like a false economy to me , as if often the case with limits on preventative care , because the cost of the test units and strips isn't huge in the greater scheme of things and if people are encouraged to use them they definitely help reduce the possibility of someone eventually needing urgent care , or requiring diabetic medication in the future .

[OldPenny]

Thanks for posting this, Pro. Those of us (including my wife and me) whose experience of wearing a CGM (Libre3) is as part of the ZOE nutrition programme will understand that from that course that the shape of the curve and its highs/lows are a result of several key factors- namely: what you've eaten, how much, in what order and whether you are exercising to any degree immediately afterwards. And that's before you factor in individual body characteristics, gender etc..Fortunately, I have no personal experience of diabetes but am aware that these CGMs are now becoming common as a tool to better understand this disease.

[pmr_nikola]

Thanks for posting. While I have no experience with CGM I agree with writer's conclusion that it is very important order in which we consume different types of carbs and how exercise helps in moderating any glucose spikes. I have a simple rule to eat "slow" carbs first ( complex carbs) and save sweets for the last :).

[AtopicGuy]

The NHS seems to have forgotten that people have lunch, and that it's perfectly normal for blood sugar levels to remain elevated for up to 2 hours after a meal. Three times in recent years, I've received panicky phone calls after having bloods taken in the early afternoon. When I'm told to fast beforehand, my levels are fine. These pointless tests and follow-ups must be costing a fortune.

[PMRpro Ambassador in reply to AtopicGuy]

Couldn't agree more! Far too much reliance on lab tests as being gospel truth. And they aren't always. If they want fasting blood - make sure there is a 9am appointment!