Doctors Behaving Irrationally: The Psychology Behind Misdiagnosis

This week (October 18-24) is LADA[1] Awareness Week. I prefer “Awareness of Adult-Onset Type 1 Diabetes” Week but that is cumbersome. Many adults with new-onset Type 1 diabetes, myself and TuDiabetes founder Manny Hernandez included, were misdiagnosed as having Type 2 diabetes, a fundamentally different disease. I had rapid-onset Type 1 diabetes with DKA (diabetic ketoacidosis) at age 35, and was misdiagnosed, and Manny’s Type 1 diabetes came on more slowly, and he was misdiagnosed. The consequences of misdiagnosis typically are that the person is undertreated, and this can result in needless suffering due to high blood sugars, rapid onset of diabetic complications, and at the most extreme death due to DKA. Adult-onset Type 1 diabetes/LADA represents about 75% of all cases of Type 1 diabetes[2], yet the myth that Type 1 diabetes is a childhood disease lives on.

In an Australian survey, one third of those with Type 1 diabetes had been initially misdiagnosed as having Type 2 diabetes. Kate Gilbert, Founder and President of The Type 1 Diabetes Network in Australia, says, “Healthcare professionals need to consider Type 1 diabetes when adults present with relevant symptoms rather than dismiss the possibility due to the patient’s age. The myth of juvenile diabetes means adults are being misdiagnosed and put in unnecessary danger. Australia has a forgotten group of Type 1 diabetics, those who are first diagnosed as adults and often receive little support or given support that is geared towards children and don’t necessarily fit their needs.” People with adult-onset Type 1 diabetes who initially were misdiagnosed as having Type 2 diabetes, strictly due to age not etiology, include Manny Hernandez, Amy Tenderich (, professional surfer Rob Blase, author June Biermann, actress Elizabeth Perkins, and prima ballerina Zippora Karz.

Doctors have been very slow to recognize the prevalence of adult-onset Type 1 diabetes, and I believe there are several factors involved, most completely unrelated to medical science. Factors include:

(1) Politics: The leading diabetes organization in the United States, the American Diabetes Association (ADA), focuses primarily on Type 2 diabetes, which naturally deserves significant attention. However, ADA focuses on Type 2 at the expense of Type 1 diabetes. ADA describes LADA as “rare” and also puts a lot of emphasis on the rarity of Type 1 diabetes (if people with adult-onset Type 1 diabetes are appropriately included in the statistics for Type 1 diabetes, it is not so rare). A person with Type 1 diabetes who worked for ADA for 12 years wrote to me, “Type 1 diabetes is the same in adults as it is in kids and, because it more commonly occurs in kids, used to be called "juvenile diabetes". In the scheme of things there are relatively few people with adult onset type 1 diabetes. The American Diabetes Association is a very reputable organization and only embraces information and treatments that have been proven by stellar research or have been scrutinized and agreed upon by panels of the country's top diabetes specialists (sometimes including international specialists).”

(2) Lack of Appropriate Diagnostic Criteria: diagnostic criteria for diabetes mellitus is based on fasting plasma glucose without any differentiation between Type 1 diabetes, Type 2 diabetes, MODY (maturity onset diabetes of the young), and other forms of diabetes. The gold standard for identifying if a person with diabetes has Type 1 autoimmune diabetes is antibody testing (glutamic acid decarboxylase antibodies (GADA), islet cell antibodies (ICA), and insulinoma-associated (IA-2) autoantibodies), yet this is not part of the diagnostic criteria. Doctors will frequently say that the testing is too expensive, yet the out-of-pocket expense is $471, and that cost is a tiny fraction of the expense of DKA treatment or any diabetic complication.

Medical personnel will often react to information about people with adult-onset Type 1 diabetes with bizarre vehemence, irrationally insisting that is simply not possible for anyone to have new-onset Type 1 diabetes over the age of 30 (no matter that Mary Tyler Moore was diagnosed with Type 1 diabetes at age 33 and Dr. Kenneth Moritsugu, former acting U.S. Surgeon General, was diagnosed at age 49). My sister’s medical chart at UCLA Medical Center states that she has an immediate family member with Type 2 diabetes (no one in our family has Type 2 diabetes) because a nurse insisted it was not possible that I acquired Type 1 diabetes at age 35.

Even prominent diabetes researchers will downplay the prevalence of adult-onset Type 1 diabetes and become apoplectic if you suggest that adult-onset Type 1 diabetes is more prevalent than childhood-onset Type 1 diabetes. Dr. Jay Skyler (Diabetes Research Institute) insists that the peak age of diagnosis is 14 for all people with Type 1 diabetes[3], yet that is statistically impossible if the majority of people are diagnosed over the age of 20.

To try to get to the heart of the matter, I discussed the problem of misdiagnosis with my cousin, who is a family practice doctor. She has practiced medicine primarily in the United States, but on sabbatical has also practiced medicine in remote areas of the Dominican Republic and Nicaragua. My cousin has diagnosed many people with adult-onset Type 1 diabetes, and she immediately orders antibody testing if a patient is thin or normal weight (or even has a few extra pounds) and has been losing weight. My cousin says that doctors these days have such limited time to spend with patients and truly listen. Doctors are barraged with information on Type 2 diabetes, and thus tend to focus in on that. Many patients come in to a doctor’s office and demand certain medications or tests, so when a patient “demands” antibody testing for autoimmune diabetes (GAD, ICA, IA-2) a doctor can balk. In medicine, it takes one generation to change mentality such as “Type 1 diabetes occurs only in children.” My cousin suggested that it is best to gently suggest to the doctor, “have you seen this AAFP (American Academy of Family Physicians) article about Type 1 diabetes in adults? I brought a copy[4]. Do you think I might have adult-onset Type 1 diabetes? I have the following symptoms/characteristics that are described as typical of adult-onset Type 1 diabetes.” Personally, I think it is important to use the term “misdiagnosed” when someone who was diagnosed as having Type 2 diabetes in fact has Type 1 diabetes, since they are two different diseases (different genetics, causes, treatments, and potential cures). However, as my cousin points out this term causes doctors to freak out, so if you are a patient it is probably best to not use the term “misdiagnosis” with your doctor.

In closing, this has been my most challenging blog to write, because I find psychology to be complex and nebulous, and I cannot understand why a correct diagnosis and “First Do No Harm” is not foremost in doctors’ minds. I welcome input, insight, and clarity from TuDiabetes members.

[1] Latent Autoimmune Diabetes in Adults, or slow-onset Type 1 autoimmune diabetes.

[2] According to the U.S. Centers for Disease Control (CDC) (Diabetes in America, 1995), of the 30,000 people newly diagnosed with Type 1 diabetes each year, 57% are adults, and the CDC states that those numbers do not include newly diagnosed people with LADA. According to Jeff Unger MD (and many other diabetes researchers) typically 10% of people with “Type 2” diabetes are antibody positive and in fact have Type 1 diabetes (according to the Type 1 diabetes definition of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus).

[3] DiaTribe Issue 14.

[4] Jeff Unger, MD. “Latent Autoimmune Diabetes in Adults.” American Family Physician. April 1 2010 Vol. 81 No. 7.

I can resonate a lot with this post. I’d like to also suggest a key reason #3 for continued misdiagnosis, “Cognitive Defect.” Most doctors, once doctors made a diagnosis, tend to explain away or discount information that conflicts with the diagnosis. They will do this as an individual and as a group, eventually when your file is large enough with material “assuming” a diagnosis it becomes impossible to stop the train of misdiagnosis without perhaps starting again with a new doctor and telling him “nothing” about your diagnositic history.

ps. And I have observed doctors followed the priority, “Do myself no harm” followed by “Do no harm.”

I know that the medical profession is supposed to be above all this but it isn’t: The issue is a very real stigma associated with T1 and it’s much more than a social stigma. There are jobs that T1’s are categorically banned from. Diagnosis with T1 is pretty much guaranteed ineligibility from every purchasing health insurance (and many times life insurance) outside a large corporate or group plan, greatly limiting career options for those who might want to favor self-employment. etc.

And I personally don’t blame a doc for not ordering expensive antibody testing. I’ve never had it.

I don’t mean to disagree with you, everyone should get good treatment, and sometimes not being diagnosed as T1 but as T2 can result in improper treatment. But as a long-term, now adult and well into middle age T1, I’m not sure that my experience in the medical system (e.g. tests, doctor visits, specialists I see, tests that are run) would be any different if I was a T2 on insulin.

And finally I look at the fact that I’m T1, and as a result some of the amazing oral medications that are “for T2’s only” aren’t possibilities for me. Wow, if I could have some metformin, its supression of gluconeogenesis sounds like it would help a lot with some of my issues (especially dawn phenomena) sounds like a dream.

I would rather the T1 and T2 classifications be abolished, and we somehow went to a system where everyone got the appropriate treatment no matter what category they were lumped in.

Interesting view Tim. My experience as a “diagnosed T2” is a bit different. I am fortunate to be in a career that is not precluded by diabetes, but precluded careers are actually rare. I have the same insurance problems, I’ve concluded that I am basically priced out of life insurance and I have the same problems as a T1 with health insurance and have the same sorts of exclusions for pre-existing conditions. With the new law, the playing field is much more level for those of us with D. And I do blame my doctor who won’t order an antibody test which costs only a fraction of the monthly cost of my inneffective oral medications. I have had thousands of dollars spent on cholesterol testing, yet I make my doctor write on my chart that I “refuse” cholesterol medication. Why is that?

I understand that for some, there may be some belief or negative stigma associated with a T1 diagnosis, but denying a T1 condition can be an easy way to health complications and an early death. It is shocking that it is the doctors not the patients that have a closed mind about the possibility of a patient being T1.

And you can get a prescription for metformin as a T1, just ask your doctor. The suppression of gluconeogenesis is not a very powerful effect, mostly it is prescribed for T1s for improvement in IR. You could try it and see if it helps? .

I was very fortunate when I was diagnosed and had a very good doctor that was ahead of his time for 1984. I kind of went cruising along for over 20 years without a problem and then landed in the hospital and I had to fight to get insulin. They had an endo come in and talk to me and after a few minutes talking to me, he said “I think you are a Type 1.” I said I have been a Type 1 since 1984. He said it was all thru my chart that I was a Type 2. I guess because I had gained some weight, they automatically assumed I must be T2 and I did not need insulin. No one ever asked and now when they have “diabetes” on their forms, I write Type 1 next to it.

I don’t think it is right when people like BSC have to struggle and the assumption is automatically made that they must not be following the rules or the stupid pills would work. Doctors treated me like that when gastroparesis was causing my BS to bounce all over – they knew I had gastroparesis and what that caused but since what they told me to do wasn’t working, I must not be listening.

BSC, what you are going thru is one reason I am not too thrilled about doctors being forced into digital records. At least now when I have garbage in my file, I don’t give it to a new doctor & start fresh. We won’t be able to do that anymore.

Thanks everyone for the interesting and thoughtful comments and for sharing your experiences. Tim, to a large degree the serious problem is for the the adult Type 1s who are kept OFF of exogenous insulin. I agree, if a person is misdiagnosed as T2 but put on exogenous insulin, it is not as big a problem. But many doctors will keep adult onset Type 1s off of insulin for years, with very serious consequences. Some will go into DKA and that essentially solves the problem, but why should someone have to go into DKA before they can get a correct diagnosis? Then some true LADAs (really slow onset) won’t go into DKA, so they remain undertreated for a very long time. Again, thanks all for your great comments.

A lot of why I write these blogs about adult-onset Type 1 and misdiagnosis is because I believe it is very important to get a correct diagnosis if you have Type 1 autoimmune diabetes, so I personally believe it is good to be correctly “labelled.” It is actually very easy to identify and diagnosed autoimmune diabetes with antibody testing, and thus get the correct treatment (earliest possible start of intensive insulin therapy). And that also means, in the United States, that you have a much greater chance of getting an insulin pump and a continuous glucose monitor. So I believe it is essential to correct a correct diagnosis to get correct treatment. And for myself personally, I want to know what disease I have.

Hi Melitta. This is a great topic and post. I totally agree with you. Before coming to our support group, I was under the impression that adult onset type 1 is extremely rare, so I was surprised to find that the majority of the women in our group, and almost every other type 1 person I have met since was diagnosed as an adult. I think there is a lot more misdiagnoses than we know about.

Hi, Melitta:
I’d like to take your argument even one step further! In my experience, doctors just are not prepared for the nuances of this disease. They expect everyone to fit into the 80-90% mold. So you and Manny were forced into the Type 2 mold when you were really suffering from an autoimmune disease - a disease with a fundamentally different etiology. It is looking more and more as though I will end up being at Type 2, but a rather atypical one. I was first dxd as T2 by my internist who put me in “the mold.” I tried controlling BG with diet and exercise - but because of strong T1 family history, I began testing, testing, testing (pre and post prandially). What I found got my attention. I was fine in terms of my fasting glucose…but my reactions to food were extreme to say the least. I hardly eat ANY carbs without going over 200. The books on T2 all said I should be able to eat around 35-40 carbs per meal…NO WAY. 10-15 was the max I could handle and sometimes not that many. After 3 weeks of testing I contacted my doc about going on meds. She talked about Metformin, but warned me of the unpleasant side effects and urged me to continue with diet and exercise, reminding me that I was “only PRE-diabetic after all.” I think she thought that I was really over reacting. After 6 weeks of eliminating carbs I emailed my doc with all the data. By this time, my nutrition plan was pretty grim. The night before, eating just 1/2 of an orange bell pepper put me up near 200. A veggie! By this time I’d found out about LADA and realized that I was of normal weight, did not have metabolic syndrome, had Hashimoto’s thyroid disease…so I really fit the criteria for LADA. All my Internist said was “That’s a lot of data.” and she referred me to the Endo. GOOD THING, because the Endo took a look at the multiple 200+ readings on my meter and pronounced me DIABETIC, not PRE-diabetic. She ran the anti-body tests and the C-peptide. Here is where it gets interesting. Appare

Gosh…don’t know WHAT happened to the rest of my post! Here is the rest of the story:
…so, I was declared a Type 2, Insulin Deficient but NOT Insulin Resistant. What?! She prescribed Onglyza for me which stimulates insulin production by the pancreas. At first, I thought it the Type 2 diagnosis was going to be temporary. I mean, I was too thin. Had the family history of T1, the Hashimoto’s etc. That surely, I was really LADA and that I was in the Honeymoon period and quite soon my condition would deteriorate. I’d start seeing my insulin production tail off and bye bye Onglyza, hello insulin. But, that has not happened. I am doing just fine. And I have been reading up and it seems it IS possible to be T2 and not Insulin Resistant. Rare. But possible. Insulin deficiency in T2’s is apparently caused by a genetic defect that causes Beta cells to die faster than they regenerate creating a gap between the insulin supply and insulin need. This death rate is called apoptosis. I’ll find out more when I see the Endo next, but, I have concluded that it is possible this is what is going on with me. I have the deficiency, no resistance…hence the diabetes and the Onglyza working. The reason I bring this up is that had I not gotten to Endo, but just gotten worse and gone back to my Internist, she would have automatically put me on Metformin. The Metformin would have done nothing as it increases insulin sensitivity. Well, I’m already sensitive to insulin…I just don’t have enough. So, that would have only wasted time. And I would have been lumped in with the 80% and if not “mis-diagnosed” treated with the wrong medication…which is why I posted to say that I wanted to take your argument one step further to say that primary care docs just are not prepared for anyone who does not fit the mold. In fact when I asked her about LADA she didn’t know much about it. So imagine what she would have said about a T2 who wasn’t insulin resistant???

This is so frustrating… I feel lucky that I rely heavily on educating myself (and not just listening to a Dr.). It was through self-education that I learned of LADA and requested a referral to an Endocrinologist. I was miserable on oral meds and not improving. I was a little nervous bringing up Type-1, GAD etc. to an expert… Didn’t want to step on her toes. But as I started to talk about it with her, she smiled and shook her head up and down. I was not sure what she was thinking. She interupted and stated that she walked by me in the hall while I was being weighed and automatically thought “she doesn’t look like a Type-2”… I feel so grateful that she is in my life!

I continue to appreciate your commentary on the misdiagnosis (and I use the term advisedly) of people with “atypical” forms of DM. You’ll notice I did not say LADA, because, NO, I still am not positive for antibodies…so I am still considered a T2, not Insulin Resistant, but Insulin Deficicient. A Skinny T2…who cannot take Metformin, the first line drug to be prescribed. So, again, had I not been SO on top of my disease that I had suspected that I had something other than run-of-the-mill T2, I would have been treated the wrong way. I believe that what would have happened is this. I would have been dx’d as Pre-diabetic T2. I would have been told to just watch my diet and exercise and the doc would have watched my FBS and my A1C about every 6 months. Because FBS is actually not bad…in the 105-110 range and it is only post-prandially that I spiked due to insulin deficiency…I would have just progressed…and it probably would have taken several years if not more for my insulin deficiency to get to the point of creating a fasting sugar of 126 or an A1C of 6.5+.

I would have been considered one of those “classic cases” of pre-diabetics who went on to develop full blown diabetes. Then my internist would have put me on Metformin. Which would have done nothing…perplexed, I would have eventually been referred to an Endo…after walking around with high blood sugars for years…and perhaps developing retinopathy, damaging my kidneys etc.

Fortunately, this did not happen. Because of my father’s history, I immediately began testing and realized just how sensitive to carbs I was. I cut back on carbs immediately and tried to control BG with diet and exercise to no avail…and got myself to an Endo who was smart enough to look at my meter with several over 200 readings and dx me as diabetic, no PRE anything and do the GAD/C-peptide testing and get me on Onglyza so I could eat a few carbs and eat a more varied diet.

In the end, this is a very complex disease. Yes, a majority of people may have the most common version of T2 with Insulin Resistance and Metabolic Disorder. But it certainly does a terrible disservice to the rest of the diabetic population when physicians are unaware of or exclude other possibilities from the diagnostic roster! Like Anna, I consider myself very lucky for having been so well educated and proactive on my own behalf…

Anna and April: You two are doing so great because you are your own best advocates! And refuse to put your respective heads in the sand!