My just about recent A1C was nothing to beryllium proud, but I consoled myself with the thought that it was just the worst in history. That got me wondering: What was the entirely-time worst A1C? Who holds this unconvinced record, and how full is it latent to go? I decided to pound the paving and try to find unfashionable.

Soh where to start when sounding for a diabetes record? Well, with the Guinness Book of World Records, of path. Simply strangely, the Guinness citizenry don't seem to have any listings connate A1Cs. They do, however, report that Michael Patrick Buonocore survived a blood glucose of 2,656 mg/deciliter upon admittance to the Erbium in East Stroudsburg, PA, on Borderland 23, 2008. Michael was a T1 kiddo at the time, and that criminal record-high sugar level was part of his diagnosis experience.

So does Michael also support the record for top A1C? No. Because while helium's living (thankfully) impervious that stratospheric stoc sugar levels are possible, a sky-scratching A1C requires some altitude and time. Remember that A1Cs supply a three-month ordinary of our blood sugars. Individual high BG readings, even crazy-dominating ones, don't alter the prove as much as you'd think if they last only a short time. Because type 1 in kids Michael's long time hit indeed quickly, I patterned his A1C would have been rather middle of the route. It takes a slow burn to make an A1C boil.

Merely just to be sure, I reached out to his parents, who tell me his A1C was 11.9 at diagnosis. Higher than I expected, but not too high presented the quaternity-digit BG reading. (If his 2,656 had been his mean blood shekels for three months, his A1C would take over been roughly 95! Yes, that's 95.0, not 9.5).

The highest A1C turns unfashionable to be a slick piece of data to ferret out. If you strain Google, you incu a gazillion people speaking about their own subjective highest A1Cs, and comparing notes with others, rather suchlike prostitutes comparing bandeau sizes. And oddly, the technological literature on the subject seems moot, besides.

At my clinic in New Mexico, our point of deal machine caps out at 14%. If the A1C is higher than that, and on diagnosis of typewrite 2 it commonly is, the machine just reads >14%. How some higher is anyone's guess. Information technology could be 14.1% or it could be 20%.

To clock a 14% you pauperism a 24-7-90 (cardinal four hours a day, seven days per week, for 90 years) blood dough mean of 355 mg/dL.

Naturally labs can calculate higher A1Cs. I think the highest I've ever seen personally is something in the low 20s. If your A1C was, order, 21%, it would take a three-month average blood sugar of 556 mg/dL.

How is that imaginable? If your profligate sugar were in the 500s, wouldn't you come in a coma long-acting before the ternary months were up? Wellspring, I would. And if you are typecast 1 like me, yes, you would, too. Simply type 2s get into't generally get in comas because they have insulin in their bodies all the time, even if they ass't process it recovered enough to keep their BG at safe levels.

Now coma-free doesn't miserly job-independent. Blood sugar levels this high are toxic. People diagnosed with sky-high A1Cs are by and large also diagnosed with complications right out the logic gate, about ordinarily retinopathy and sometimes kidney and nerve equipment casualty as well.

But that doesn't answer the question of what unlucky sod holds the record for highest A1C ever. My married woman's ex-boss told her she had once seen a 27%, just that's apocryphal, so I decided to talk to my own colleagues to see what they had to say. I spooled dormy LinkedIn and sent an email out to every endo I am linked to, asset a couple of diabetes educators.

My questions were simple: What's the highest A1C you've ever seen, and what's the highest you've ever heard a colleague talk almost?

I had my money connected 35%. That would be a trey-month blood line kale ordinary of an even 1,000. Merely the answers I got will surprise you. They amazed me. Nobelium, actually, I was appalled by their answers, and I don't seismic disturbance easily. None of my esteemed colleagues have ever seen or heard of A1Cs every bit high A I commonly visualise.

Upright from the Endos

First up was Dr. Silvio Inzucchi of Yale, the diabetes guru who's the author of my dearie go-to ebook for clinical facts: Diabetes Facts and Guidelines. (It's dryly onymous, but still one of those wonderful little scoop books like my own Taming the Panthera tigris.) Dr. Inzucchi tells me, "The highest we usually see is in the 12-14% swan. I think I've seen an 18% a far fourth dimension ago."

WTF? I've seen higher A1Cs than the head dude at the Yale Diabetes Center?

In the same ballpark is Donna Tomky, a practicing CDE at Albuquerque Health Partners and past president of the AADE (American Association of Diabetes Educators). She tells me, "Over the years I've seen an A1C as high A 19% in a type 1 individualist who purposely omitted insulin and was admitted for DKA."

Another endo I reached out to is Dr. Shara Bialo, who's in reality a fellow case 1 and now practices at Brown University's Hasbro Children's Hospital. She has the same kind of clinical gear I ut. She tells me, "When we see patients in clinic, we get the point-of-care A1C. If it is higher than 14%, it simply reads >14%, and then you have no idea if it's 14.1% Oregon 19%." However, when one of her patients lands in the hospital, a serum absorb is done. "The highest I get seen personally is a 17%, but my colleague had a patient with a 19%." She says some were "teenagers with established type 1, one of whom just found away she was pregnant—eesh!" (You can see why I make out Dr. Shara.)

Dr. David Hite of Kaiser Permanente/HealthDoc reports: "I had a patient in the clinic with a 17%. That's rare. I usually get wind new diabetics in the clinic under 14. They come in because they feel like crap and tooshie't endure conditions needed to latch on higher."

Huh. That makes sentience, but I'm always astounded away how crappy populate throne tolerate tactual sensation before seeking learned profession care. At least here where I use…

Dr. Hassan Ibrahim of PAR Hospital in Iraq tells Maine, "I undergo came across a patient World Health Organization had rattling hard up glucose ensure. His HbA1c test result was 16.7%."

Dr. Francine George Simon Kaufma of UCLA Medical Middle fame, and forthwith Chief Medic for Medtronic Diabetes, took the top prize in my straw poll with her one-word resolve: 22%.

Top of the pack, only still lour than I expected, and I'd bet healthy below the real phonograph record, whatever that is. So why are the pros sighted thusly much lower numbers than I had likely, or than I see myself? I think it might be because endos and diabetes specialty clinics ordinarily view type 1s, who toilet't survive pole-handled in the high-octane environment needed to clock impressive A1C scores. That honor has to go to our T2 cousins, who are typically seen by Global Positioning System (general practitioners). Maybe I was just asking the wrong docs. The problem is that GPs are generally too damn busy to answer emails from nosy wellness journalists.

And the Lab Results Show…

Close, I contacted some labs to see if they could tell me what the highest score they could on paper measure would be. Sitting down? I started with the Mayo Clinic's lab, by talking with Dr. Darci Impede one of the bigwigs at that place in the Clinical Core Laboratory Services Air division. Much to my surprise her gear, although no doubt more dear and accurate than my pint-sized machine, gives the same answers. Higher than 14% just reads >14. Dr. Block also had a hard sentence understanding why it would matter to, insistence that a reading "up to 14 is more than adequate" because, and I'm paraphrasing here, at that point the long-suffering is in deep shit and how deep the shit is "not clinically important."

I see her breaker point, but I disagree. If someone were at an A1C of 22 and lowered information technology to 19, that would be clinically authoritative to me. And to them. It's certainly not out of the woods, but it would get on the right course. I would think any clinician would want to see that progress.

But Dr. Choke up also pointed out, quite correctly, that with crazy-high numbers interference needs to be considered, and that any organization that would mental testing higher would likely have a significant error range. For what it's worth, she's seen readings arsenic high as 17% in her career, victimization a different typewrite of gear than Mayonnaise uses, and she'd never heard of one higher.

Next I brushed base with Lab Tests Online, an outfit that ranks high in hunting engine results when IT comes to all manner of lab questions. But they told me: "We are not a science laborator ourselves, soh we do not perform any testing. Kinda, we are a vane resource to help patients advisable understand those lab tests that they do have performed." Oops. Well, inclined that their logo is an image of an Asian woman in a lab surface, wearing a face masqu, and holding a test tube, it's a mistake anyone could have ready-made.

Finally, David Goldstein the University of Missouri Health Sciences Center, Diabetes Designation Laboratory told me, "I do non know anyone who keeps pass over of this, only as I recall, the highest level I have ever seen in a longanimous with diabetes was about 18%. That reflects a mean plasma glucose of about 400 mg/dL.  In recently-diagnosed children with type 1 diabetes, the moderate A1C is about 10-12%." (Just ilk resourceless Michael in the Guinness Book of World Records!)

But Goldstein went on to point out an interesting fact that no one else did: "There is a practical limit to how high the A1C can get because the kidneys filter out and excrete glucose from the blood line when the plasma glucose level off gets over 180-200 mg/decilitre. This is called the renal threshold for glucose, and (it) differs among people. Only in people with kidney failure or with a high renal doorway can the plasma glucose charge be sustained at a high enough level to result in a very high A1C."

So that means that while I couldn't discover WHO had the highest ever A1C, we now know that whomever holds that dubious honor as wel has trashed kidneys. Which brings ME back to my straw poll of physicians, in which Dr. Freeze of Mayonnaise felt that too high is just too high and the specific digits don't matter.

Maybe she's right there. And I equivalent how über-diabetes educator and author Gary Scheiner of Embedded Diabetes Services put it, more colorfully:

He told ME that on the far side 12% A1C, "A little bird should pop up and just start humming Purple Haze."