Testing for A1C

I was speaking to a few people in the medical field ( AIDS counselor, nutritionist, and a few others) about testing for the A1C. All of these folks stated that blood would have to be drawn to have it tested properly. I told them I normally have a pin prick done at my Endo's office during a visit. I get test results in a few minutes.

What am I missing? What is the difference between getting blood drawn into a vial versus the finger prick?

I just had blood drawn for an A1C, but also blood was taken for other tests, you know, cholesterol, tryglycerides, etc. etc. I dread going back to get the results! Different country, different methods.

There is a long distrust with many in various medical fields, about any tests not done by a "lab".

The A1C meters in endos offices are pretty good but the machines are not calibrated every day nor are the calibrations traceable to a national standard.

The lab machines are calibrated frequently and traceable to national standards.

But just because they aren't super-duper calibrated doesn't mean that non-lab tests aren't worthwhile. Think about, every fingerstick bg you and I have ever done was checked by a meter that fits in our pocket. That bucks the medical establishment to its core - especially when the patient gets to see the result before the doc. When home bg testing first became widely available about 30 years ago you wouldn't believe how much controversy it stirred up - the thought that the patient would see the result before the doc was simply scandalous. Yet it proved so worthwhile in the end especially after the establishment got hip with it.

I suspect in terms of educational value that the little A1C machines in endos offices, are most valuable especially for folks who haven't had an A1C done at a lab and who may not check their bg at home regularly or even at all.

Thanks for answering.

What prompted this was my effort in trying to set up a testing site to do A1C testing on the spot in certain areas. This would be done with qualified professionals.

I understand when blood is drawn it is normally used for a host of test and the A1C is included. But if there is a quicky way of doing it that could tell a person they need to be further checked I am all for it. I just need some "battle" information to go back and tell these people they can perform the testing. They have no problems doing AIDS testing on the spot why not Diabetes?

It's easy enough, Christalyn, to buy a home A1C kit; they cost about $30 and have two tests per kit. My understanding is they are considered quite close to the lab tests in accuracy. No "qualified professionals" needed. Last year when they had the free A1C tests at Walgreens for World Diabetes Day, that was actually what was used.

I have read that many doctors office in house testing makes use of the home tests or the institutional equivalent. For your purposes they seem fine, but they can be waaaaaay off for someone trying to maintain tight control. I quit using them as a supplement to my drawn blood lab tests when I pulled a number a full point over my actual. Got me all worked up for nothing. The test would have been good for an initial diagnosis most if the time, but they can be off by about +/-20% per my experience.

I discussed this with a specialist some time back and was told that lab tests are more accurate. Not sure why or the rhyme and reason behind it.

I always get my cholesterol;, micro albumin, thyroid etc checked at the same time, plus the path-lab hospital is a two minutes walk up the hill, so I don't mind giving abit more blood ha.

When I was in the teenage clinic (with the same doctors I see now) they used to use a finger pricking test for HbA1c, they got rid of it though as it was expensive.

Plus my doctor is excellent, I just have to contact the surgery, ask for the tests I want done and the request is ready within 24 hours.

I have used the disposables. Available for a time for $19.99 at Walgreens here in Ohio,The results, kind of like my MM sensors, could be very variable. Sometimes they were right on the money with the lab test;some times WAAY off: Once my a1c came up 8.8 on a in-office A1c ( just like the one I had from Walgreen). My doctor and I know that from my
downloaded meter results and my past blood glucose histories, that such a result was not likely. So he asked it to be run again in the lab, along with the other bloodwork. My
A1c though not at the range we wanted, was 7.5, more than a full point less....I also do not know if it would be cost-efficent to do a $20.00 test at a screening site, unless the disposable a1cs can be mass-ordered from a supplier, like the doctors do. Will the agency that funds you, christalyn, be able to "dig deep" in their pockets if discount pricing cannot be had?
I hope so... They may be off, but better to have it for those who have not had a long-term blood glucose test in quite a while.

God Bless,

And how are You Ms. Christalyn?

The HbA1c is actually a pretty crude test. The current criteria for being a "certified" test is basically +/- 0.75% (and this is an "improvement") . That means that having two tests, one at 8.8% and a second at 7.5% could still be within the allowable variation. That is almost totally useless as far as I am concerned.

As to the specific at home tests, the Bayer A1cNow is certified within allowable accuracies.

ps. It is also important to understand that there are some specific things can lead to false outcomes with the A1c. These include things which cause greater or lesser turnover of blood cells, but another one is sickle cell trait. Certain tests, such as the Bayer A1CNow are vulnerable to this interference.

Thanks for the info, bsc. I was using the Walgreen's brand at home. I am African-American, but no sickle cell trait in me. Thus, I not know why there was such a variability, on the same day ,with the doctor's office test and the lab resullts.(?)

God bless,

As others have said, the A1c home test kits are too expensive, and not very accurate. If you want to do a screening in order to refer people to docs for further evaluation (which is all you can legally do), why not just use a random BG? Much cheaper, even using disposable one-use lancets (that don't require a lancing device). Lots of health fairs already do that.

The problem with random BGs is that if it's been 3-5 hours since a person ate, if he's an early-stage Type 2, his BG might have come down to normal levels, so one thing might be to advise people to be tested within 2 hours of eating a high-carb meal. But even then, the person may have a "normal" fasting BG or A1c lab test -- a big issue is that the criteria for diagnosing Type 2 are pretty lousy right now. So your attempts at screening may cause some to be brushed off by their docs (and consequently mad at you), but on the other hand, you might catch a few undiagnosed diabetics by doing this.

I am doing alot better! I am trying to get some things done for Black history month especially with doing A1C testing in the malls. I was trying to work with an AIDS group and ran to some resistance. UGGGHHH! Which prompted this question.

Otherwise I bought an xbox 360 because best buy was having a super sale on it with the kinect body scanner. I have been having fun playing the dance fitness games as well as the shootem up war games. This is my first game system. I never had an atari!

How are you and retirement!!!

I understand that I cant get everything I want. So if I can catch a few undiagnosed diabetics that will be good enough. I was not aware the DR offices were using just the take home kit from the drug store. In my ignorance I thought they would be a bit more sophisticated.

I would be interested in knowing how labs test for A1C. Being a scientist, I have a curiosity for all the intricate details and interactions.

All I know is that labs have fancy machines. When I went to AADE, I got my A1c done on a lab machine, and also on an A1cNow by Bayer. The first was 5.7, and the second was 5.8, so mine was accurate but another woman got a difference of more than one whole percentage point. That's why I don't really trust the home tests -- I don't want to be lulled into a false sense of complacency by a false result.

Are you in the US?

There are "health fairs" in many communities, where medical professionals use portable meters (kinda like the A1C meters in endos offices or the hospital class portable bg test meters) and do spot testing of A1C's and bg's. This is great for screening purposes. I think this is exactly what you are looking to do.

I think there is some small-print disclaimer that this is only a preliminary screening and that only real labs can make the definitive test yada yada yada.

Personally I think the whole blood testing rigamorale has gotten out of hand. I was diagnosed 30 years ago without a blood test at all. Presenting in DKA and having my urine turn the clinitest jet black instantly might have been good enough back then :-)

They also have on-site testing for cholesterol at some of these health fairs. I think this actually takes a "machine" and not just a test strip but I could be wrong.

That is almost totally useless as far as I am concerned.

We like to put a lot of emphasis on blood tests here and in fact in the broader world the emphasis on A1C numbers seems to be growing... but to presume that a single blood test can be the judge of a person's health or even just their bg control... is probably not the most useful concept.

Blood tests and numbers are very useful tools, don't get me wrong. But I was diagnosed T1 without a blood test at all 30+ years ago. Today there are so many hoops one has to jump through to be diagnosed, it seems like all the tests are just makng things more complicated.

Copied From Wikipedia: There are a number of techniques used to measure A1C.

Laboratories use:
high-performance liquid chromatography (HPLC): The HbA1c result is calculated as a ratio to total hemoglobin by using a chromatogram.

Point of care (e.g., doctor's surgery) devices use:
boronate affinity chromatography

In the United States, POC A1C tests are certified by the National Glycohemoglobin Standardization Program (NGSP) to standardise them against the results of the 1993 Diabetes Control and Complications Trial (DCCT).[9] There is an additional percentage scale, Mono S, that is in use by Japan and Sweden.[10]

From my own experience with diabetes I find the A1C is not much use to me really. I have compared my lab drawn A1C with home A1C tests and once a mail in test and they were the same results. I do not think the A1C should be used for dx, but it is better than nothing.

Yeah, but the whole point is to find Type 2's, in whom the diagnosis is not nearly so obvious as it is in a child in DKA. They can go years gradually declining, but not feeling sick, and by the time someone notices that something is not right, they already have complications. Wouldn't it be nice to find them BEFORE they lose a leg, or have a hemorrhage in their eye or have renal failure or an early heart attack?

I'm in favor of MORE screening for Type 2, and at younger ages, too. The test is cheap enough that it doesn't make sense NOT to!

See my post in response to your other post about diagnosing Type 2. It's more like catching people who fall through the cracks than making them jump through hoops. After all, who in their right mind would want to be diagnosed with diabetes?

I agree completely about screening and making it easy and accessible. If I read some here (and in fact I know that some endos offices have a similar policy), it's not possible to get a diabetes diagnosis without fasting bg, A1C, GTT, GAD, C-Peptide all being run at some fancy pants lab.

But it can be a lot easier too. I would push towards the easy end.