Glucose Meter Differences, New Meter

[Louellen]

Not sure if this is the right forum to post this on or not but, has anyone had any experiences with getting a new meter and it being different in readings than their previous meter?

I just got a new Bayer Contour Next meter for Morrigan because it will allow the strips to add more blood without having to throw it away if there isn't enough the first try. That's a savings right there.
However, when Hubby and I tested ourselves with the both the new meter (Bayer Contour Next) and the old (Bayer Contour) the NEW meter read both of us at 1.1 mmol/l LOWER than our old meter. We BOTH tried it to check the difference and both got a 1.1 to 1.2 difference in the readings between old and new.

That said, I called the Bayer company today. They said that these new meters (Bayer Contour Next) are more accurate than the older version. Apparently, the old Bayer Contour had a 20% difference from lab test results whereas, the newer version Bayer Contour Next, has an accuracy of only a 10% difference from lab tested glucose readings.

So, given that, they said to test with the newer meter. However, that now puts Morrigan's numbers DOWN by 1.1 to 1.2 mmol/l than they are, if that is the case. Not that it matters much at this level but, now I'm concerned as to what to believe or not believe.

They are sending me the "solution" to check the old Bayer Contour meter (we did diagnostics on both meters over the phone and both units are working well) but, that will take 5 to 9 days to get here. But, now I am questioning whether to stick with the OLD meter for now or change to the new meter as we've been going by the old meter's readings.

Anyone have any thoughts or have had that experience? Would love your feedback on this topic if you can as the vet has told us not to shoot if the numbers are below 10. (We mostly catch her AFTER eating as she will not eat if we test pre-meal if that makes any difference in things???)

Thank you in advance.

 

[manxcat419]

Tricky one to answer as of course any meter is only really giving us an "it's in the range of this" number as they're all subject to a variance of up to +/-20%, so you can get 2 different readings even using the same meter and the same drop of blood taking 2 tests only seconds apart. I'd have thought if the new meter has been tested to be within +/-10% instead of 20% then overall it will be more accurate so it may well be that the lower numbers are actually right. Getting the control solution isn't a bad idea - it's definitely worth checking the old meter for accuracy though the numbers you're getting with the new meter aren't so far off that anything sounds particularly wrong with either of them.

I think you can go with whichever meter you're most comfortable using until you get the control solution through. What I would advise is that you pick one meter to use until then and stick with it exclusively rather than trying to run some tests on one and some on the other. You can of course switch to the other meter at any time you choose, but if you do that then again once you switch I'd stick with just that one meter. We all know about meter variance and we do allow for it when necessary, but for me at least although I am aware of the variance I tend to take the numbers I get as being the actual numbers unless I've got a reason to think they need questioning so switching between meters that read slightly differently can throw your thinking off a little.

 

[manxcat419]

Oh, missed the bit I meant to add about testing after food

It takes about 20 minutes for food to start getting into their bloodstream after they've eaten so as long as you're getting the test right after she eats, it shouldn't be making much of a difference if any.

 

[BJM]

If you can test within about 10-15 minutes of eating, any food impact will be negligible for low carb foods. Try feeding a tablespoon first, then testing, then putting down the rest of the food.

 

[Louellen]

Thank you @manxcat419 and @BJM I was thinking the same way in terms of sticking to the one meter for now. I stayed with the old meter for now because it's a measure that I'm seeing on the chart vs changing to a lower number meter.

I will wait for the solution to get here and test and THEN, I may switch to the new meter and stick with it as the cost of the strips is the same as the old meter BUT will allow me to add more blood if I get an insufficient sample the first try. That happens quite frequently and I can go through nearly $3:00 in strips in one day with the old meter.

I totally agree though with the idea of sticking to ONE meter and not changing back and forth.
And, you're right Manx...even Hubby has done a test for his own diabetes, been unbelieving of the number, done another test right away and gotten a totally different number within seconds...still same blood pool.

Tech support at Bayer made a very good point and had a good suggestion. Hubby is going in for his blood work-up this week for his own diabetes. They suggested that he take both meters with him (Morrigan's current meter and the new) and right after they draw his blood, take a meter reading with both meters, mark down the numbers then wait for the lab results and see which one is closer to the lab results. (He uses his own meter...not Morrigan's...which is his older unit, sanitized ). He said he's willing to do it.

And, yes...I TRY so hard to get her blood sample within the 10 to 15 minute range after eating but, if she even hears the sound of the zipper on the kit opening, she flees and hides and won't eat. So, I try to get her to eat and get the test within 10 to 15 minutes then, if she wishes, try to get her to eat a bit more. More often than not...she's fled the "crime scene" and gone under something, somewhere. Rarely does she eat again after that so, I've learned to let her eat and NOT touch that test kit zipper before she's done!

I think I will stick to the old meter until I have both the solution and hubby has his results from the lab then, will decide which one to stick with and stick with it. It is only a "range" and her fructosamine level was done on Thursday of this past week. It showed nearly "excellent control" (down from 505 to 403 and he wants it down to the 300's) so, I'm questioning the OLD meter now. Those numbers don't seem to indicate to me, "good control"??? But....I guess the trend is coming down, which is a good sign, I hope.

Thank you both so very much. Your responses validated for me, my own thoughts on the matter. I hope this helps others who may be reading along and wondering the same thing too.

HUGS to both of you.

 

[manxcat419]

They suggested that he take both meters with him (Morrigan's current meter and the new) and right after they draw his blood, take a meter reading with both meters, mark down the numbers then wait for the lab results and see which one is closer to the lab results.

That's a great idea! That will definitely help you find out which meter comes in closest to a lab machine. And if it turns out to be the new one, then Morrigan's doing better than you thought!

I TRY so hard to get her blood sample within the 10 to 15 minute range after eating

You can only do what's possible. Morrigan has to eat so scaring her off from her food isn't an option. You're getting tests and you're getting some of them within that 10 to 15 minutes - that's as much as you can expect from yourself (or Morrigan) for now. Maybe she'll settle better with testing or maybe she'll be one of those cats that always hates it, but you're doing as much as you possibly can. Your AMPS today might include the start of a food spike, but as long as you're aware of that and know not to worry about it too much that's not too much of a problem while she's mostly in yellow.

her fructosamine level was done on Thursday of this past week. It showed nearly "excellent control" (down from 505 to 403 and he wants it down to the 300's) so, I'm questioning the OLD meter now. Those numbers don't seem to indicate to me, "good control"???

I think you might find that the new meter turns out to be the more accurate one and that her numbers are actually lower than you've been thinking they are - but of course that's really good news! And on a straight comparison from her first tests to now, yes her trend is downwards. If you finish up able to take another 1.2 or so off those readings (and 10% of 200 takes off rather more than 10% of 100 of course) then she'll be looking even better!

 

[Louellen]

That's a great idea! That will definitely help you find out which meter comes in closest to a lab machine. And if it turns out to be the new one, then Morrigan's doing better than you thought!


You can only do what's possible. Morrigan has to eat so scaring her off from her food isn't an option. You're getting tests and you're getting some of them within that 10 to 15 minutes - that's as much as you can expect from yourself (or Morrigan) for now. Maybe she'll settle better with testing or maybe she'll be one of those cats that always hates it, but you're doing as much as you possibly can. Your AMPS today might include the start of a food spike, but as long as you're aware of that and know not to worry about it too much that's not too much of a problem while she's mostly in yellow.


I think you might find that the new meter turns out to be the more accurate one and that her numbers are actually lower than you've been thinking they are - but of course that's really good news! And on a straight comparison from her first tests to now, yes her trend is downwards. If you finish up able to take another 1.2 or so off those readings (and 10% of 200 takes off rather more than 10% of 100 of course) then she'll be looking even better!

You are always so very supportive and uplifting and I thank you for that from the bottom of my heart. Just when I get really down and worried, you seem to be able to keep me thinking in a different direction...the UPSIDE of things.

Morrigan was my baby who came to me without looking for her, just when my heart was broken over losing my previous Sugar Kitty, Topper. I guess I am so terrified of losing her too. And, who would have thought that the kitty who took over a huge hole left by Topper...would ALSO turn diabetic? So, your help and support mean so very much to me...as does that of all the wonderful, kind, loving people in this forum.

 

[manxcat419]

There's always an upside to everything - sometimes it just takes someone else to see it first as it's so easy to get caught up in the details!

It seems to me that Topper sent Morrigan to you knowing you could take care of her and keep her well. I really do think our GA kitties still look out for us and send us another furbaby to love when they think we're ready. Topper must have picked Morrigan just for you knowing that you'd be able to cope with her diabetes just as you did with his!

 

[123joan]

Happy to read this discussion this morning, as I just purchased a new meter myself. Of course I had to do the exact same thing, test the same drop of blood with each meter, and worry that the results differed. Now I will scratch this issue off my worry list. Thank you! I've been buying WalMart ReliOn test strips for years, but while in Kroger last week heard them promoting their diabetes supplies. The meter is $4.00, and test strips $4.00 for 25, $8.00 for 50, $16.00 for 100. Nice!

 

[BJM]

Per the FDA, meters readings in the US are allowed to be +/- 20% of what a lab may get. I believe I read the standard will be tightened up to +/- 10%, so Bayer is ahead of the game on this meter. The blood drop size is double what is used for the Arkray USA Glucocard 01 and 01 Mini (aka WalMart ReliOn Confirm and Confirm Micro).

I will note that this +/- 20% requirement is when testing humans, not cats, so we'll have to see how the Contour Next works out. The tech info online states that the meter runs 7 pulses through the sample to generate the result.

 

[Louellen]

Thank you all. I just received the solutions to test both meters and am going to read the literature and do the testing on the meters to see the differences.
Hubby has taken both meter with him to the lab as he is getting his blood work done for his own diabetes today.
As suggested by Bayer Tech Support, he is going to take his levels on BOTH meters, note the numbers and will compare them to the lab results when he gets them next week *IF* the doc has put down a glucose test on the requisition. Thus far, we can only decipher the A1C so, he may not be able to talk the lab into a plain glucose number with that sample but, we'll see.

That may be the only true measure and it may help others in here too.
Will update this when I get the results as I'm sure many are wondering about meters too.

 

[BJM]

Do a search on glucometers in the search box up right. The topic has come up numerous, numerous times before. Home glucometers are intended to be an aid, not a replacement, for lab tests.

 

[Louellen]

Thank you @BJM

I should have looked there first. I guess, as a newer member, we don't think to look there first.

I will remember to not post a question from here on in until I have searched the forum data base first.

 

[Louellen]

I do have a question though @BJM (thank you...I did a search on meters in the forums ) and found this post made by you to another member (thank you again).

"The human meters, on the average, test about 30-40% lower than pet meters. This data comes from international feline diabetes expert Dr Rand of the University of Queensland who obtained hundreds of paired tests when doing studies of feline diabetes. She observed the human meters reading an average of 30-40% lower values values and noted it in several of her research publications.

If you recall from your basic school studies, you get the average by summing up all the test scores, then dividing by the number of tests. There will be some tests higher than this average; there will be some tests lower than this average. (Well, unless everyone gets the exact same score!)

When you compare the difference between any 2 meters, the difference between them when using the same blood drop will vary, even at the same glucose level. Part of this is because the meters sold in the US are allowed to test as much as 20% lower or higher than what a lab would get.

Calculating the +/- 20% for Dulce:
The AT test of 72 means her glucose was somewhere between 57.6 to 86.4.
The EGP test of 54 means her glucose was somewhere between 43.2 to 64.8 .

The 2 meters could be as much as (86.4-43.2) or 43.2 mg/dL apart, or as little as (67.8-56.6) or 7.2 mg/dL apart, depending on whether each meter was reading high or low or someplace in between.

The EGP could be from 50% lower (1-[43.2/86.4]) to 18% higher than the AT value ([67.8/57.6]-1).
The AT could be from 100% higher than the EGP value ([86.4/43.2]-1) to 11% lower than the EGP value (1-[57.6/64.8]).

Calculating the +/- 20% for Badgar:
The AT test of 377 means his glucose was somewhere between 301.6 to 452.4.
The EGP test 331 means his glucose was somewhere between 264.8 to 397.2.

The 2 meters could be as much as (452.4-264.8) or 187.6 mg/dL apart, or as little as (397.2-301.6) or 95.6 mg/dL apart, depending on whether each meter was reading high or low or someplace in between.

The EGP could be from 41% lower (1-[264.8/452.4]) to 32% higher (1-[397.2/301.6]) than the AT value.
The AT could be from 71% higher (1-[452.4/264.8]) to 24% lower (1-[301.6/397.2]) than the EGP value.

Using just 2 pairs of tests (4 total tests) and the +/- 20% variance shows that the possible differences may vary widely.
The research Dr Rand did with many more tests narrowed down the average percent difference."

My question is this.....
Given the above data that you've so kindly typed out for us all, I'm wondering if given all of the above data and all of the % differences between meters types, pet and human values etc., there seems to be quite a high percentage of differences not only between meters themselves but, also in readings from each meter as well as pet vs human meters.

Those differences might not be as much of a concern if numbers are within good ranges or more moderate ranges and may act as only a "guide".
While I DO totally agree with the idea that meters are only guides/aids...marking possibly only "trends" per say, I then, have a whole different view on the "TR shooting" that is advocated.

What I mean by that, is that IF one is going by numbers on these meters and therefore changing dosages on their own, (which a lot of members seem to be following from what I'm seeing happening), wouldn't that make it a rather dangerous thing to be doing, based upon these percentage differences?
That might be especially true when numbers are more or less falling within the yellow, blue and especially green numbers.
If these meters are that wide in variance then, for instance Kitty A might be getting dosages according to their meter readings whereby, Kitty B who might be in the same ranges on their meters...are being upped and lowered on dosages according to those numbers, possibly by the same amounts, according to TR dosing guidelines.
Given that possible factor, then...wouldn't that then make it a rather dicey practice to be raising/lowering dosages according to meter readings and not via blood tests from vets as you've so wisely mentioned???

I'm not arguing anything...just concerned and really confused now that I've read these numbers as you've posted them and watching the threads and reading other's SS's, along with dosing protocols etc.. How does one deal with those differences in meter readings without lab tests which are truer numbers to dose by?

 

[BJM]

There is a buffer zone on the low end for cats on insulin - we don't want them to go below 50 mg/dL, because that could be as low as 40 mg/dL where there is a real possibility of hypoglycemic symptoms and harm to the cat. At higher numbers, the guidelines for TR have been shown to be safe using human or pet glucometers, and the dose adjustments being made are done after allowing the dose to stabilize/settle, plus are in small enough increments (0.25 - 0.5 units) that a drastic response is unlikely. Plus, notice how the instruction has you hold the dose longer as you start getting into lower numbers which also improves the safety.

A home glucometer - even with the +/- 20% variability - is adequate for monitoring diabetes in humans, who adjust their insulin based on their home tests, or cats, where we do the dose monitoring and adjustment. Whenever you get an unusual test, test again. If they are widely different, test a 3rd time for the closest 2 out of 3. And the overlap between the 2 closest tests is where the true value is likely to lie.

Other than that, you also should look at the Whole Cat Report, or 5 Ps (purring, preening, playing, peeing, and pooing), and take a look at my signature link Secondary Monitoring Tools, because your cat is more than a glucose number.

 

[Louellen]

Ahhhhh...ok...got it. Thanks BJM!

Oh and yes...now that we only have the one cat, it's far easier to keep track of the litter box activities so, we have a diary of those figures too.

 

[Brashworks]

Thank you all. I just received the solutions to test both meters and am going to read the literature and do the testing on the meters to see the differences.
Hubby has taken both meter with him to the lab as he is getting his blood work done for his own diabetes today.
As suggested by Bayer Tech Support, he is going to take his levels on BOTH meters, note the numbers and will compare them to the lab results when he gets them next week *IF* the doc has put down a glucose test on the requisition. Thus far, we can only decipher the A1C so, he may not be able to talk the lab into a plain glucose number with that sample but, we'll see.

That may be the only true measure and it may help others in here too.
Will update this when I get the results as I'm sure many are wondering about meters too.

Hi Louellen - did you ever get these results? I'm thinking of changing meters - actually I'm down on strips and Bayer is offering a free Contour Next with the purchase of 100 strips. Since the strips are comparably priced for both the Next and my current meter (OneTouch Ultra 2) I figure it would be nice to have the option.

Even if you just had the difference between your old Contour and the Next when using the test solution - I'm curious.

Thanks!

 

[Meya14]

The new FDA guidelines (I couldn't find when they went into effect) is 15%+- for home meters, and 10%+- for meters that are used in health care settings that don't have a CLIA waiver. Some OTC meters that are being sold are dual use, so must adhere to the 10%, some are only for home use, so 15%.

 

[Louellen]

Hi Louellen - did you ever get these results? I'm thinking of changing meters - actually I'm down on strips and Bayer is offering a free Contour Next with the purchase of 100 strips. Since the strips are comparably priced for both the Next and my current meter (OneTouch Ultra 2) I figure it would be nice to have the option.

Even if you just had the difference between your old Contour and the Next when using the test solution - I'm curious.

Thanks!

Yes, Brashworks....the Bayer Contour differed from the Bayer Contour Next by about 0.5 on my hubby (using same drop of blood). Bayer Contour measured higher than the Bayer Contour Next. The lab results were within the 15% range on the Bayer Contour from the lab results but, within 10% for the Bayer Contour Next. The lab result was a little higher than either meter but not any really big difference. I couldn't remember the difference between the meters and the lab results and neither could he but, we both remember that the lab results were a bit higher than the meters. However, this is not always the case allegedly. The lab technician told hubby that their samples are also going to be "off" at the lab because it will vary from when they get the sample and when it is processed. It will even differ (same blood) between labs so, it's the general overview that they want...not specific numbers.

So, that said...I really like the Bayer Contour Next as it seems to be more consistent in my estimation and experience. Now, the Bayer Contour is said to be more around the 20% difference from lab tests and perhaps, on repeated tests...that would be the case. But, that's at the lower numbers. Once you get past 13 on the meters, the accuracy drops so, not sure what it does to the Bayer Contour but, the Bayer Contour Next is said to be 10% below 13 and 15% above 13.

I thought that I would like the ability to add more blood on the same strip but, it really doesn't give you enough time to do that with our cats. It's really more a convenience if you can work up enough blood within about 20 seconds to add to it. Not sure it's worth the cost of the strips as they are a bit more expensive than the Bayer Contour.

Speak to your pharmacist and see what he/she has to say about them or, call Bayer and see what they have to say. I only know that this is what we have right now and it's ok for our purposes (as guides) in both hubby and Morrigan (they each have their own lancets and meters but, share the bottles of strips as insurance paid for hubby's strips and he got a free meter but, Morrigan's we paid for the strips to get the meter free). Ugh...costly!

Does this help?

 

[Brashworks]

Hi Louellen and Meya, thanks for your replies.

I was reading human reviews of the Contour Next and I like that fact that I can store my readings on their software - I have a Mac and the Next is compatible (most are only Windows compatible that I've seen).

@Louellen, I'm glad to hear you like the Next for consistency, too. I just started Genghis on Lantus last night so I think I will try to find a place that carries the Next and do some side-by-side comparisons with my OneTouch just so I can get a baseline. Genghis is a more… cooperative … test subject than Morrigan so the "second chance strips" might be of some benefit. But if I understand the basic baseline difference between the two meters (if any) I have the option of using either meter and pouncing on test strip special pricing, and I'll still know where Genghis is "at". I hear what you are saying about the general overview - it's easy to get caught up in the numbers sometimes!

While I'm sorry your hubby is diabetic, I'm glad you can get free strips for Morrigan. Every time I wasted one in the past, I though, crap, there goes $1. I could have bought another can of food with that!