Continuous Glucose Monitor

It works well with a pacemaker

by Gemita - 2024-10-04 15:11:43

sybrsuzy,

My husband has a continuous glucose monitor which was recommended by his Diabetes Clinic.  The monitor is linked to his clinic and they automatically receive his blood glucose results too, so they can watch him closely.  It is true, the instructions say the monitor has not been tested for use with a pacemaker, but it clearly works well with a pacemaker.  Several members here successfully use it. 

We have fully tested the monitor and compared the results with those from the HbA1c quarterly blood glucose results that our doctors request.   The monitor is accurately recording the correct values.  We have been using the monitor successfully for around a year and wouldn't be without it.  

You might want to avoid placing the monitor on the pacemaker side arm, since we did have some interference there on first using it.  Abbott tells me that they are currently testing the monitor for use with pacemakers, so they should soon have the studies to back up what they can and cannot say.   Abbott are very helpful should you get into difficulty and they will always send a replacement monitor if you return the faulty one.

If you need any further help, please let me know.  Good luck and you will love the monitor.  I don't know how we lived without it

Glucose

by piglet22 - 2024-10-05 06:57:22

Morning Gemita.

You are well placed to know about these things, more than most.

The only thing I would say is that working units of measurement need to be clear.

I'm not going to get myself into hot water by defining them, but the surgery likes their HbA1c in mmol/mol (normal level below 42 or thereabouts, which can be expressed as a percentage, about 6%, or there's blood glucose as mmol/litre.

There's the difference in the two methods of course, average against instantaneous, so it's important to know what's being measured.

There's an ad on the TV at the moment for Freestyle continuous monitoring that shows happy user and a result of 6.2.

6.2 what?.

I used a basic finger prick instantaneous measurement in units I can understand mmol/litre.

This translates as one thousandth of a mol or mole of glucose per litre of blood, where a mol(e) is the molecular weight of glucose in grams. A molar solution is one mole of a substance dissolved in something.

Despite many years in labs etc., and analytical chemistry, mmol/mol is a new one on me. Clearly it's a ratio because it can be expressed as a percentage, but what does mmol per mol mean? As it stands, it looks like it's always going to be one thousandth if it's the same substance or something else if they are different substances.

I only add this because you say you compare the results.

Even after a quick Google, I didn't find a convincing definition of mmol/mol.

On Diabetes UK, they have a nice table under what is HbA1c? that compares the three glucose concentrations (mmol/mol, %, and mmol/litre.

My GP texts me with dire warnings if I drift over 42 mmol/mol HbA1c.

My long term monitoring of 12 years by blood glucose finger prick under the same conditions, first thing in the morning before breakfast, shows that my levels can be normal (below 6 mmol/litre), impaired (6 to less than 7), or diabetic (7 or above).

There is a spread of values, not excessive,, but the trend line (Excel  graphing) has a slope of nearly zero i.e. no upward or downward trend which I find reassuring set against the annual surgery test.

I say annual, but the interval is getting longer.

I do check the test accuracy with Roche calibration standards which is the key to all methodology in analysis.

I haven't looked into the chemistry of finger prick, one off HbA1c, or continuous, but I would expect that companies like Roche and Freestyle have done extensive testing.

The methods available now for all these blood tests is truly amazing and hats off to all the researchers doing the fundamental work.

Please forgive any errors in typing as this microscopic keyboard and screen are doing my eyes in.

PS

I knew it.

The wretched phone turned prick into print and mol into mil. There's smart technology and not so smart technology.

sybrsuzy

by piglet22 - 2024-10-05 10:21:32

Anyone or company producing something like a continuous glucose monitor, would have done a considerable amount of testing before coming to market.

Some of the pacemaker manufacturers produce continuous monitors so would be well aware of any device interaction, specifically electronic and data conflicts.

Of course, development and changes will take place as more user information becomes available.

My only concerns would be cost of ownership, lifetime of sensors, and how well the chemistry gets on when subjected to weather, skin condition, sweat etc.

Piglet

by Gemita - 2024-10-05 12:33:09

Piglet you ask some challenging questions. 

I was more comfortable seeing the HbA1c test (amount of glucose attached to the body’s red blood cells, indicating blood glucose control over the last 2-3 months) expressed as a percentage rather than shown in mmol/mol.  

You are correct, working units of measurement need to be clear and mmol/mol is not clear to me either.   Nonetheless our clinic confirms that my husband’s glucose level results from the Freestyle monitor are always within range when comparing these with his HbA1c levels.  I will ask my clinic what mmol/mol actually means in simple terms and get back to you unless we find the answer ourselves Piglet? 

We have been working with the specialist diabetes nurse for a couple of years.  She recommended the Freestyle continuous sensor monitor primarily for ease of monitoring multiple times a day, since the finger pricks were becoming painful and difficult to manage. 

We were told all meters will give slightly different readings and not to worry about this.  A meter reading is an “indication” only of the patient’s glucose status.  They do not seem to worry about exact measurements of these numbers. 

The patient’s health status can also suddenly affect these readings, for example if they have a UTI, glucose levels may suddenly increase particularly with antiobiotics.  If the patient starts or stops a medication it could affect glucose levels too.  Lifestyle (particularly lack of exercise) can massively affect glucose levels as can eating refined carbs which in turn affects the periodic HbA1c levels.  

We have been told my husband’s glucose levels because of his age and other health conditions, is acceptable in the range HbA1c 62 mmol/mol.  Last period it was higher: 79 mmol/mol.   Our Freestyle monitor data provides info on the % time spent in ranges:

more than 13.9 mmol/L;  

between 10.1 and 13.9 mmol/L;  

target range 3.9 - 10.0 mmol/L;  

Low 3.0-3.8 mmol/L and 

Very Low, less than 3.0 mmol/L.  

It also gives the Average plasma Glucose level, hubby’s most recent being 10.9 mmol/L.  It gives lots of other interesting info.  Wish I could share my App with you.  Quite impressive charts.

When it comes to monitoring glucose levels, it is important to factor in the patient’s age, other health conditions, lifestyle, medication before worrying about strict control of those numbers.  It is also so important that we watch for symptoms of very high or low glucose levels which might then require immediate action.  Those numbers are sometimes meaningless on their own.  Watching the patient for symptoms and assessing what is the correct amount of insulin or medication to take at any given time is more important.  All the calculations in the world or knowing how exactly they are arrived at, aren’t going to help if we fail to listen to the patient or to watch for symptoms that may come on all too quickly.

https://www.diabetes.co.uk/what-is-hba1c.html

https://www.diabetes.ascensia.co.uk/about-diabetes/hba1c-monitoring/

Personally, I feel that doctors can be too rigid about those glucose numbers and do not always consider the whole person.  Diabetes control will never work if we feel we have to keep to a rigid plan/diet.  It is far better in my experience to be slightly above the target range and to stay there rather than failing miserably with all aspects of treatment.  I get quite upset when Michael doesn't stick to his diet, but that doesn't help either of us.  He has to live and to be happy at 86 years of age, otherwise all the monitoring in the world will serve no useful purpose

Piglet and Sybrsuzy

by Gemita - 2024-10-05 12:47:15

Yes the Abbott Libre Freestyle monitors have clearly been fully tested, but they still error occasionally and the patient has accidents like knocking them off.  The manufacturer is always willing to replace them, in my experience, even if the accident was our fault.

The monitors cost around £51 in the UK for two sensors and are usually recommended for those who need to monitor their glucose levels many times a day (for both Type 1 and Type 2 diabetes).  The sensors last 14 days and then need to be replaced in a different position each time.  

Monitors rarely detach in a steamy shower or during hot conditions.  It is important however, to place the monitor on a well prepared, clean and dry part of the upper inner arm for best results.  

We are extremely fortunate here in the UK because many of us get these expensive monitors free of charge on the NHS if we qualify for them

CGM

by Xtrabeat - 2024-10-05 14:35:21

I think someone else asked exactly the same question in the "chat" a while ago. I used a CGM as part of the Zoe trial and had no problems with it or the PM despite my placing it on my left arm and problably withing 6 inches (the magic number - for mobile devices etc :)) of the PM site. The data generated was quite intereesting for me and I have modified my eating considerably since. If you are worried about it I would suggest placing it on the oppeosite side to your PM. 

CGM

by sybrsuzy - 2024-10-05 20:50:00

Thank you, everyone, for you responses.  I am going to try to convince my endocrinologist to prescribe this.