Experimenting with a CGM

[Flane]

Hi, I have just trialled a (Dexcom One+) CGM for a week to get an idea of what my BG is doing. At the end, my average BG was 5.8 mmol/L., having restricted my carb intake to a "manageable" level for me. When I had 24 hours without carbs, my BG was very low - and overnight went into the red zone. My last Hba1c in December was 45, and it will be interesting to see if it will have reduced in June if I continue on this low(ish) carb diet. Fortunately my weight has now stabilized but I cannot put any back on (BMI < 20).

It's an interesting journey......

I don't think I'll use a CGM again for a while but it was worth doing and I now have the graphs to show to the Prediabetes clinic if they are interested!

 

[Anwers on a postcard]

I did the same... and have actually subscribed to keep an eye, I've found it very eye opening and probably helping me be more strict with myself. Average for the past 3 days is 5.0mmol/l but when I started this 5 weeks ago it was sitting at 5.7. 30 day average is 5.4 so definately seeing an improvement. Costly to keep it going (circa £80 per month) but think I'll go for at least 3 months and if it helps stop complications and keeps me off medication I'm willing to do it, I'm due and HBA1C test in May so will be interesting to see the impact. Most recent was 40 so in a good place but would like to see that drop a little.
Upcoming stag weekend for my BIL will be a challenge to maintain that though!

 

[Flane]

I did the same... and have actually subscribed to keep an eye, I've found it very eye opening and probably helping me be more strict with myself. Average for the past 3 days is 5.0mmol/l but when I started this 5 weeks ago it was sitting at 5.7. 30 day average is 5.4 so definately seeing an improvement. Costly to keep it going (circa £80 per month) but think I'll go for at least 3 months and if it helps stop complications and keeps me off medication I'm willing to do it, I'm due and HBA1C test in May so will be interesting to see the impact. Most recent was 40 so in a good place but would like to see that drop a little.
Upcoming stag weekend for my BIL will be a challenge to maintain that though!

Thanks for your reply. It will be interesting for us both to see how our Hba1c measures up against the average glucose from the CGM. My next test is in June.

 

[grantg]

Thanks for your reply. It will be interesting for us both to see how our Hba1c measures up against the average glucose from the CGM. My next test is in June.

Hba1c i thought was approx 3 months blood glucose average, with a little more weight to most recent weeks? u could try abbots trial (which is 15 days) libre2 plus / libre 3 closer to the time i'd guess would be more accurate than basing off the present cgm readings a couple of months prior to the blood test?

 

[Flane]

Hba1c i thought was approx 3 months blood glucose average, with a little more weight to most recent weeks? u could try abbots trial (which is 15 days) libre2 plus / libre 3 closer to the time i'd guess would be more accurate than basing off the present cgm readings a couple of months prior to the blood test?

Yes, I thought I’d see what the levels are like at the end of May, but at least now feel I have a better understanding of the impact of what I am eating. I find it very hard to cut out carbs completely so I’d like to get to something that is manageable for me.

 

[Flane]

So....I'm now trying the Libre 2 and with similar eating patterns and carb intake, I'm seeing higher glucose numbers- where with the Dexcom I was seeing around 5.4/5.6, I'm seeing steady-state over 6.0/6.6 with the Libre. Is this to be expected? Or does it indicate that my levels have gone up in the last 3 weeks? It's early days with the Libre, but I'm not sure where this is all going...

Any thoughts would be very welcome! Thank you

 

[Melgar]

@Flane , blood sugar measuring devices such as cgms have an allowable accuracy of 15% -/+. So those figures fall within that accuracy range. I experience similar between my cgm and my glucometer. Also slowly rising blood sugars are better viewed month by month rather than day by day. I hope that helps.

Edited to for clarity.

 

[Flane]

@Flane , blood sugar measuring devices such as cgms have an allowable accuracy of 15% -/+. So those figures fall within that accuracy range. I experience similar between my cgm and my glucometer. Also slowly rising blood sugars are better viewed month by month rather than day by day. I hope that helps.

Edited to for clarity.

Thank you, yes, very helpful. I will look at trends rather than absolute values.

 

[becca59]

As a type one, that sort of differential in reading I would consider totally negligible and not worth a second thought. If you have access to more than one blood glucose meter and did a test at the same time i bet they would show that sort of differential.

 

[Flane]

As a type one, that sort of differential in reading I would consider totally negligible and not worth a second thought. If you have access to more than one blood glucose meter and did a test at the same time i bet they would show that sort of differential.

Thank you. That is very interesting. I will definitely focus on the shape of the graph and trends rather than the absolute figures. I am hoping to bring my hba1c back into the “normal” range.

 

[Anwers on a postcard]

Thanks for your reply. It will be interesting for us both to see how our Hba1c measures up against the average glucose from the CGM. My next test is in June.

So I thought I'd come back with an update on this and my feelings.. I subscribed to the dexcom one plus and am now 58 days in.
I happened to randomly get a free health screening at work and my HBA1c came back at 39 which is great. (It peaked at 50 circa 18 months ago) this also is in line with the GMI from the dexcom of 5.7%.
It will still be interesting how that stacks up against the NHS tests in May but hopefully similar or better.

I've become a little obsessed with the readings, very handy to understand what impacts my blood sugar and which way it is moving but also possibly restrictive in that I over check it.
If I was to go with the old adage of checking it 2 hours after eating, I can fairly confidently say that I am under 7.8mmol/l 99% of the time, probably more, if I've been "bad" or misunderstood what I was eating there might be a very brief spike to above 10 (I think my highest was 11) but comes back down to the 7.8 level or less within 30 minutes. Sometimes getting a little sticky around the 7 mark for one or two hours depending on how "bad".
My findings with the CGM are possibly less positive, I find when my BG is in the range of 5-7 it is fairly consistent with my blood measuring machine, if it's higher or lower than that the readings become quite erratic and tend to read higher or lower than the actual sometimes by quite a long way.
I also find the first 36-48 hours are awful, consistently reading 1-2mmol higher than actual which can be quite concerning. They advise not attempting to calibrate during that period, which I understand the reasoning behind but do find it quite disconcerting and stressful. (as above I get obsessed with the reading and hate seeing the averages rise, that is probably just down to me).
Other findings:
1) a glass or two of red wine will reduce my average level and "fasting" level by 1mmol/l or more for 24 hours or more.
2) Lager, beers or stout are not really my friend (I've got a Guiness factory tour booked on saturday so may well test that theory again...).
3) Sleep: Quality is important, too much or too little has an impact but a good 6 hours of sleep gives better results than 7 hours with some broken sleep in there.
4) Eating late will mean a higher fasting level, even if there isn't any noticable spike in levels.
5) I like my morning coffee but noticed my sugar could rise quite a bit after that in the morning, I tried dropping the milk and going for black coffee and thought it improved things. Then noticed that started having the same impact so started adding some milk again with little impact. What it now seems is if my fasting level is around 4.8-5.2 the coffee may cause a short term increase to around 6. If it's over 5.2 (I am usually under 5.5 except unexplainably this morning when it was 5.9) then the impact is much more and might raise it to 7 or a little more which then leaves me questioning breakfast choices that morning. I am now putting this down to the quality of sleep issue I noted above and think I need to work on that.
6) We all know this but exercise is our friend, it is very visible with the CGM what this impact is. If I see my sugars rising quicker than I like a 20 minute walk works wonders and will keep everything at a sensible level. I'm fortunate enough to have a treadmill in the house so even a quick walk on there after food that is having more impact than expected will do the trick (18 minutes at circa 5km/h seems to be the sweet spot for me).

So my thoughts on the CGM:
1) For me, it's been an interesting time. Certainly giving me insights into my bodies reactions
2) I am a worrier and don't like not having complete control or understanding of my bodies reactions (I suppose we probably all are to an extent)
3) I think using it as a tool to see the current trends in your blood sugar is good but not sure on the numeric figure accuracy on an individual reading basis.
I've just cancelled my subscription, I may decide to restart it but hope I've given myself enough insite into my reactions to food etc that I can make sensible judgements and keep things under control and at current levels. I might change my mind on that, I've got 6 days left on the current sensor and another in the drawer so have a couple of weeks before I go cold turkey

Apologies for the long rambling post, I think I just needed to get my thoughts down on paper and out of my head.

 

[Melgar]

Well done @Anwers on a postcard. That's great. Know your body, best sums it up. Everyone is different when it comes to blood sugars, but there are some basics we all agree on, carbs increase blood sugars, by how much is the question. I don't eat after 5pm. That's my personal rule for myself. I always take a brisk walk after a meal. I use exercise to bring down my blood sugars, I too have a treadmill and I use it. It sounds like you are on this, well done.

 

[Flane]

So I thought I'd come back with an update on this and my feelings.. I subscribed to the dexcom one plus and am now 58 days in.
I happened to randomly get a free health screening at work and my HBA1c came back at 39 which is great. (It peaked at 50 circa 18 months ago) this also is in line with the GMI from the dexcom of 5.7%.
It will still be interesting how that stacks up against the NHS tests in May but hopefully similar or better.

I've become a little obsessed with the readings, very handy to understand what impacts my blood sugar and which way it is moving but also possibly restrictive in that I over check it.
If I was to go with the old adage of checking it 2 hours after eating, I can fairly confidently say that I am under 7.8mmol/l 99% of the time, probably more, if I've been "bad" or misunderstood what I was eating there might be a very brief spike to above 10 (I think my highest was 11) but comes back down to the 7.8 level or less within 30 minutes. Sometimes getting a little sticky around the 7 mark for one or two hours depending on how "bad".
My findings with the CGM are possibly less positive, I find when my BG is in the range of 5-7 it is fairly consistent with my blood measuring machine, if it's higher or lower than that the readings become quite erratic and tend to read higher or lower than the actual sometimes by quite a long way.
I also find the first 36-48 hours are awful, consistently reading 1-2mmol higher than actual which can be quite concerning. They advise not attempting to calibrate during that period, which I understand the reasoning behind but do find it quite disconcerting and stressful. (as above I get obsessed with the reading and hate seeing the averages rise, that is probably just down to me).
Other findings:
1) a glass or two of red wine will reduce my average level and "fasting" level by 1mmol/l or more for 24 hours or more.
2) Lager, beers or stout are not really my friend (I've got a Guiness factory tour booked on saturday so may well test that theory again...).
3) Sleep: Quality is important, too much or too little has an impact but a good 6 hours of sleep gives better results than 7 hours with some broken sleep in there.
4) Eating late will mean a higher fasting level, even if there isn't any noticable spike in levels.
5) I like my morning coffee but noticed my sugar could rise quite a bit after that in the morning, I tried dropping the milk and going for black coffee and thought it improved things. Then noticed that started having the same impact so started adding some milk again with little impact. What it now seems is if my fasting level is around 4.8-5.2 the coffee may cause a short term increase to around 6. If it's over 5.2 (I am usually under 5.5 except unexplainably this morning when it was 5.9) then the impact is much more and might raise it to 7 or a little more which then leaves me questioning breakfast choices that morning. I am now putting this down to the quality of sleep issue I noted above and think I need to work on that.
6) We all know this but exercise is our friend, it is very visible with the CGM what this impact is. If I see my sugars rising quicker than I like a 20 minute walk works wonders and will keep everything at a sensible level. I'm fortunate enough to have a treadmill in the house so even a quick walk on there after food that is having more impact than expected will do the trick (18 minutes at circa 5km/h seems to be the sweet spot for me).

So my thoughts on the CGM:
1) For me, it's been an interesting time. Certainly giving me insights into my bodies reactions
2) I am a worrier and don't like not having complete control or understanding of my bodies reactions (I suppose we probably all are to an extent)
3) I think using it as a tool to see the current trends in your blood sugar is good but not sure on the numeric figure accuracy on an individual reading basis.
I've just cancelled my subscription, I may decide to restart it but hope I've given myself enough insite into my reactions to food etc that I can make sensible judgements and keep things under control and at current levels. I might change my mind on that, I've got 6 days left on the current sensor and another in the drawer so have a couple of weeks before I go cold turkey

Apologies for the long rambling post, I think I just needed to get my thoughts down on paper and out of my head.

Thank you - this is all very interesting and good to see that there is someone else who thinks in a similar way to I do!

I will reply in more detail later - but thank you.