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My GP hbA1c results and my fasting blood glucose don't add up

V

Virusnoot

Member
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6
Hi all,

A couple months ago I made a post here regarding some concern I had that I might be pre-diabetic, type 2 diabetes runs rife in the family and usually we get it ages 20-30 (I've just turned 23).

Over the past couple of months, I've taken morning fasting glucose tests in controlled environments, my morning blood glucose hovers between 6 mmol/L and 6.4 mmol/L which according to various sources is pre diabetic.

I've also done 16 hour fasting sessions ( as part of diet) and my blood glucose comes back at around 6.4 mmol/L.

I went to my GP who was hesitant to give me an A1c test as I am 'young' and 'fit', but I persisted as I would rather act sooner than later. The A1c test result came back as 33 (sorry unsure of units) which the GP said is fine and asked that I do not track my blood glucose again.

I've also done 2 hour blood glucose tests before and after eating, the results are usually within 1mmol/L (today it was 6.4 mmol/L before eating and 7.2mmol/L after 2 hours since eating)

So I'm just really unsure of what to do now, I've looked up dawn phenomenon, and that would make sense right after waking up, however I've had much larger fasting sessions than 8 hours and it still comes up above 6 mmol/L.

In any case I still feel like my blood glucose is creeping up, despite my GP saying I have nothing to worry about. And I just wanted some opinions from the lovely people here, unfortunately there doesn't seem to be a lot of information out there regarding something like this, so any advice or wisdom is much appreciated.

I'm using a glucolab finger prick test for my fasting BG levels.

Edit: might also be worth saying that I used the controlled solution for the glucolab meter and it came back as 5.4 mmol/L which is in the 'normal' category, so it should be working?

Thanks
 
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Hi @Virusnoot,

HbA1c tests are often not exact and can be off by a small margin as they assume your red blood cells live for exactly three months. If your red blood cells are shorter or longer lived than this, results tend to be a bit off, plus there also some other conditions, such as anaemia for example, that can influence blood test results.

Personally, I tend to trust my meter more. However, this being said, your numbers are still normal or close to normal, so personally I wouldn't worry too much. It might still be good idea imo to keep an eye on things, though.
 
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Thank you for the response! I should have noted I did the h1a1c 3 months ago and I did another one 6 months before that and both came back 'normal'. But I get the feeling 'normal' for my GP is if I'm not heading towards heart attack, but regardless I think my BG levels are high (lowest fasting BG I've read is around 5.3 mmol/L)

I agree that the meter reading is important, is it worth getting an additional meter just to make sure there are no meter errors?
 
Hi @Virusnoot,

I find it is easier to stick with just one meter. I checked fasting blood sugars on the day of blood tests against my official fasting results and found my meter was reasonably accurate. (But even if it's off, you would get an idea by how much.)

Even if you had two meters and they disagreed, which one would you believe?
 
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It isn't a good idea to use 2 different meters. As @ziggy_w said, which would you believe? All meters have to pass the same accuracy test before they can be marketed. I always trust my meter. I do not and never have trusted my HbA1c as the 2 do not agree - ever. As said before, several things can affect the HbA1c, from thyroid issues to anaemia, and from irregular red blood cells and haematocrits to red blood cells that live longer or shorter than 3 months. (and there is no way of us knowing how long our red blood cells live without special tests under medical supervision in research labs. ) Do you have blood test results available on-line, or do you have print outs? If so, check how your red blood cells are behaving, and what your thyroid tests reveal.

You are clearly not going to get any sort of diagnosis with an HbA1c of 33, but there is no reason why you can't "pretend" and follow a suitable T2 diet, which may well bring your fasting levels down. It may not be food related of course, it may be hormone related as hormones play a big part in fasting levels, whether that fast is 8 hours or 16 hours, and the stress hormones also play a major role.
 

Thanks for the reply.

I actually have 2 blood tests, 6 months apart, both in the low 30s. The reason I'm pushing so hard on getting numerous checks is because my GP is adamant there is nothing wrong with me (I have done a range of blood tests from thyroid to vitamin D) and the only deficiency I have is a vitamin D deficiency. Also my weight is 74.5kg at a height of 6 ft 3, so both GPs I have seen weren't interested in my blood glucose diary which shows my fasting blood glucose anywhere from 5.6-6.4 mmol/L (+my dad has type 2 diabetes)

For me a hb1a1c of 33 spells trouble anyway, because it means my blood glucose is already on the high side (5.4+ for a non pre-diabetic, non diabetic doesn't seem great to me).

I do lead a stressful life, but surely if my blood glucose is high because of that then there should be more insulin being pumped in my body to combat that, admittedly the most stressful moments for me are right before I take the blood glucose reading because it feels like I'm rolling random dice each time.

But thank you, I have started dropping carbs to bring it down and reading posts around here, I just wish my GPs would take my concerns more seriously
 
33 is great and of no concern. Your 6.4 fasting after a 16hr fast is more then likely the result of not having eaten for so long, so your liver has fed your system for you by releasing X amount of glucose. This is a perfectly natural process.

If you want more info, get your c-peptide tested to see how much insulin you're producing. Your doctor won't order it, but you can get it done privately. @Jim Lahey has had it done privately I believe, so he may be able to help you out if you are interested.
 

Not quite. I had a fasting insulin test and additionally used the data to calculate my HOMA-IR. I used Medichecks, but they have since stopped accepting blood samples for insulin testing via the postal service. They do still offer it, but the blood has to be drawn at select clinics, making it far less convenient.
 

Oops, well there ya go. My referencing is clearly not reliable and I may have to go into hiding. Sorry about that @Virusnoot
 
I was diagnosed earlier this year with t2 and it had been at the back of my mind due to family history too. Mum's side of family often hit t2 in mid 40s. (46!)
It was always there but I didn't know pre diabetic was even a thing. I was diagnosed with a 101 score.
48 is the point at which they diagnose diabetes although I don't know the number for pre d.
I do remember in my 20s being paranoid that each dizzy moment or stomach ache could be diabetes I even went to the Dr about it who sent me away too!

I think in your shoes I'd stop doing morning bs as they are not telling you much. How your body reacts to carbs tells you more.

Your numbers are pretty good for glucose and there isn't a huge spike after eating. This website says between 4 and 6 and others between 4 and 7. My husband who's definitely not diabetic is 6.4 whenever we've tested him.

I do understand that you feel like this is hanging over you waiting to happen but it might not! I would probably suggest, with the information you now have at your fingertips, that you think about your diet. Maybe dropping a few carb heavy meals and using your knowledge to steer a path away from diabetes. Keep fit and healthy, consider how many carbs you're eating (and drinking!!) and try to relax over it a little. Being anxious and stressed about it won't help now or in the long run.
 
The HBA1c is the mean average of about 300,000 blood tests but your fbg tells you just that you have a slightly elevated fbg which may just be caused by the body's waking up (dawn phenommenom). In other words the GP needs an elevated fbg as well as HBA1c to diagnose t2. Prior to getting t2 as others have pointed out your insulin levels would be elevated, you may have tummy fat, high ldl cholesterol, high triglycerides, low hdl and high blood pressure.
in any case, what would you do differently if you were diagnosed btw? It is not inevitable that you will get type 2 in spite of your genetic risk and changing your diet and lifestyle might be the key. Remember that the earlier you get it the more damage it can do and nothing you do re changing this will have any health risks and would be far more effective than taking any meds in preventing or treating the diabetes.
 
I am mystified by your concerns about an HbA1c result of 33 mmol/mol. Seems to me more likely that you were the least diabetic person the GP had seen all week.
As others have said, the tools to stay as splendidly healthy as you are are in your hands, and hurrah for that. You will surely be giving yourself the best possible chance for staying well in the future.
 
According to the creator of the insulin assay, Dr Kraft, type 2 diabetes is caused by insulin resistance, not elevated blood glucose levels.Lots of other evidence backs this up. High BG is the very last step in the process. It is definitely worth thinking about this, OP.

The most accurate, but sadly most impractical, way to know is to measure insulin levels. Instead, there are various proxies that can give some sort of indication of insulin resistance.

In either case OP, for peace of mind on the BG levels question , one comparison on a different glucometer might confirm the accuracy of your device with levels taken from the same place at the same time.
 
Mrright said:
In either case OP, for peace of mind on the BG levels question , one comparison on a different glucometer might confirm the accuracy of your device with levels taken from the same place at the same time.
Click to expand...

I can't agree with this. How will it confirm the accuracy or otherwise of the poster's meter? If the readings are very different, who is to say which of them is correct, or indeed if either of them is correct. ?
 
Bluetit1802 said:
I can't agree with this. How will it confirm the accuracy or otherwise of the poster's meter? If the readings are very different, who is to say which of them is correct, or indeed if either of them is correct. ?
Click to expand...
lol it will at least highlight if one of the two meters is not calibrated properly if the results are markedly different. my prediction is they will be very much aligned. it is called a second opinion . it is done in the engineering world very often to test a piece of equipment. out of curiosity , what exactly would you suggest?
 

On the whole, I agree with this. I've long held the view that the overemphasis on blood glucose is simply monitoring the symptom rather than treating the cause. This is especially true if one subscribes to the glucose overflow hypothesis of hyperinsulinemia.
 
I'm puzzled by this, as Medichecks seems to offer both C-peptide and fasting insulin tests, both DIY. I don't understand the difference between the two, but the prices are very different. I am actually not keen on the DIY version, but I am struggling to find a clinic based test.
https://www.medichecks.com/fertility-tests/insulin https://www.medichecks.com/diabetes-tests/c-peptide

PS I just managed to find the Medichecks list of clinics. I'm still wondering about the difference between the two tests, though.

PPS I now see the insulin test is only available in London, but the c-peptide blood draw is available in various convenient Superdrug pharmacies.
 
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The insulin test is listed as venous blood sample. More details available at checkout.

C-peptide is an indirect marker of insulin secretion. Insulin testing (typically fasting) is a direct measurement. I’m not super familiar with the former, but my understanding is that it’s a more elastic test than the latter (longer half-life) and is more usually used as a marker of postprandial insulin.

Others may know more about C-peptide. I was only interested in my fasting insulin so that I could calculate HOMA-IR against my own glucose reading.
 
Prediabetes is not well defined, the 3 different tests results in different people being labled as high risk of developing type2, and there is limited overlap on who each test detects.

The prediabetes lable is of no direct use to healthcare, and only is used as a method for deciding who should be given lifestyles advice etc. Your allready know from your family history that your body is not likely to cope long term from lots of suger and carbs, along with knowing that being physically active is good for you.

Hence I don't think there is any benefit in thinking about if you are in the prediabetes group.
 
Good luck on your journey! I’ve been worried by my fasting blood glucose trending upwards and feeling my control has been poor, so I measured my HBA1c using the PTS diagnostics A1CNow self check. My GP has sent me away with a flea in my ear for believing joint stiffness and pins and needles was related to pre-diabetes (ok he refered me to neurologist), so I know it can be frustrating to feel unheard. The advice on this website that is widespread is to “eat to your meter” that is find out which foods (1 AND 2 hours after eating) spike your blood sugar levels. The US based website bloodsugar101.com tells you how to duplicate the ORal Glucose test at home, as this was their diagnostic, which could be another sense check. Focus on your health (eating well & being active) not on an illness you are at risk for, would be my opinion.
 
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