Acute-Onset Type 1 Diabetes in Adults: Overlooked and Ignored

Rapid onset Type 1 diabetes in childhood, previously called "juvenile diabetes," gets the most visibility; it affects about 15,000 children per year in the United States[1].  Slowly progressive Type 1 diabetes (aka LADA (latent autoimmune diabetes in adults)) is now garnering much more attention, mostly in medical research journals but now more frequently in mainstream publications.  By my calculations, slowly progressive Type 1 diabetes (LADA) represents the vast majority of all new cases of Type 1 diabetes annually; new-onset LADA affects about 145,000 adults per year, or about 10% of new cases of “Type 2” diabetes in the United States[2].  But what about the adults with acute-onset Type 1 diabetes, who actually outnumber those children with new-onset Type 1 diabetes[3]?  Tragically we are overlooked, ignored, and still usually misdiagnosed as Type 2 diabetes based on age not etiology.

I experienced acute-onset Type 1 diabetes at age 35, but was misdiagnosed by the hospital’s on-call endocrinologist as having Type 2 diabetes, based on age not phenotype.  Fortunately, I only remained misdiagnosed for one week.  I recently polled members of the diabetes social media site TuDiabetes.org, and here are some select stories and commentaries about acute-onset Type 1 diabetes, and what the adult with T1D wishes medical practitioners understood:

• At age 30, soon after she retired as professional ballet dancer, Kris was misdiagnosed as having Type 2 diabetes and told by her doctor to lose weight (at 5’6” tall, Kris weighed less than 100 pounds) and exercise more. Her doctor scolded her when the “lifestyle changes” that he ordered did nothing for her, because in her doctor’s mind the problem was that Kris was not following his directives.  Kris went into diabetic ketoacidosis, lapsed into a coma, and thankfully was found by friends and rushed to the emergency room.  Initially in the emergency room the doctors accused her of not following her treatment protocol thereby bringing DKA upon herself, until they called in an endocrinologist who realized she had been misdiagnosed and given incorrect treatment.  In the ER, the endocrinologist correctly diagnosed Kris as having Type 1 diabetes.
• Michael, a competitive bicyclist, was misdiagnosed as having Type 2 diabetes at age 42.  Others advised Michael to get autoantibody testing, which his doctor initially refused to perform.  Finally, when his doctor reluctantly ordered the autoantibody tests and the tests came back positive, his doctor sent him a letter via snail mail saying he “might” have Type 1 diabetes.  Michael was denied insulin for 12 months.
• Marybeth was hospitalized in DKA at the age of 60, but incorrectly diagnosed as having Type 2 diabetes strictly based on age, not etiology.  Marybeth was fit, active, normal weight, and displayed extreme sensitivity to insulin in the ER.  Six months prior to hospitalization, Marybeth’s fasting blood glucose was 74 mg/dl at a health screening, indicating that her diabetes onset was rapid. Marybeth says, “If I had followed my hospital discharge instructions I would probably be dead” and “Clinicians need to be brought up to date on the incidence of Type 1 diabetes in adults. They need to look at the whole picture. Emergency room doctors especially need to use their brains not just a blindly follow a Standard Operating Procedure (SOP).”
• Jen, misdiagnosed at age 22, says, “I hope that more medical professionals realize how misdiagnosing adults with type 2 diabetes instead of type 1 can be dangerous and carries a very significant mental and physical toll on the newly diagnosed diabetic.”

In polling members of TuDiabetes, I was struck by the degree to which the medical community downplays the seriousness of adult-onset Type 1 diabetes.  Children with new-onset Type 1 diabetes are given due respect; yet all too often adults are told they don’t even deserve correct diagnosis and treatment.  This perception is slowly changing—The Type 1 Diabetes Sourcebook (ADA/JDRF, 2013) recognizes the seriousness of adult-onset Type 1 diabetes and the need for correct diagnosis and appropriate treatment.  Dr. Steven Edelman, founder of Taking Control of Your Diabetes (TCOYD), advocates correct diagnosis and treatment, and at the medical education lectures that Dr. Edelman gives around the United States he encourages medical practitioners to look out for LADA patients and order autoantibody testing.  Slowly, the tide is turning.

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[1] SEARCH for Diabetes in Youth, research sponsor U.S. Centers for Disease Control and Prevention (CDC).

[2] This is an estimated number based on 37 years of autoantibody testing that indicates that approximately 10% of people diagnosed with “Type 2” diabetes are autoantibody positive and by definition have Type 1 autoimmune diabetes.  Michael J. Haller MD, in Type 1 Diabetes Sourcebook (ADA/JDRF, 2013), says “Importantly, adults with LADA may represent an additional 10% of those adults incorrectly diagnosed with Type 2 diabetes.”  The first study that demonstrated that about 10% of people with “Type 2” diabetes are autoantibody positive was published in The Lancet in 1977, now 37 years ago (Irvine WJ, Gray RS, McCallum CJ, Duncan LJP: Clinical and pathogenic significance of pancreatic-islet-cell antibodies in diabetics treated with oral hypoglycaemic agents. Lancet1 :1025–1027,1977).  In the United Kingdom Prospective Diabetes Study (UKPDS), about 10% of people diagnosed with “Type 2” diabetes were autoantibody positive and had been misdiagnosed.

[3] The U.S. Centers for Disease Control and Prevention’s (CDC’s) most current information on the prevalence and incidence of Type 1 diabetes comes from Diabetes in America, Chapter 3, “Prevalence and Incidence of Insulin-Dependent Diabetes” (Diabetes in America, Second Edition, 1995).  Although people who use that reference as a source of incidence statistics state that there are about 30,000 new cases of Type 1 diabetes each year and that half of those cases are children; in fact, that source states that children (<20 years of age) account for 13,171 cases and adults (>20 years of age) account for 16,542 cases, for a total of 29,713 new cases of Type 1 diabetes per year, 56% seen in adults.  Thus, new cases of acute-onset T1D in adults exceed new cases of acute-onset T1D in children.  Additionally, that source states that there is an unknown number of adults identified as having Type 2 diabetes who have slowly progressive Type 1 diabetes.

Bill of Rights for People with Adult-Onset Type 1 Diabetes Or “A Manifesto for the Misdiagnosed”

There are many names for adult-onset Type 1 diabetes, including latent autoimmune diabetes in adults (LADA)[1], Type 1.5 diabetes, and slowly progressive Type 1 diabetes[2].  Although the majority of new-onset Type 1 diabetes always has been seen in adults[3], the myth that Type 1 diabetes is a childhood disease often means adults with Type 1 are misdiagnosed as having Type 2 diabetes and/or given substandard treatment.  Here is my manifesto:

·         Correct diagnosis:  If an adult is diagnosed with diabetes and does not appear to fit a more typical profile for Type 2 diabetes (i.e., the adult is not overweight, does not have abdominal obesity, is not insulin resistant, does not have a family history of Type 2 diabetes, and does not have metabolic syndrome), the person should be tested to see if he/she has Type 1 autoimmune diabetes.  The gold-standard test for Type 1 diabetes is autoantibody testing (glutamic acid decarboxylase autoantibodies (GADA), islet cell autoantibodies (ICA), insulin autoantibodies, insulinoma-associated (IA-2) autoantibodies, and zinc transporter autoantibodies (ZnT8)), and the c-peptide test is also useful but not definitive.  If the person is autoantibody positive, he/she has Type 1 diabetes.

·         Insulin treatment:  Intensive insulin therapy should begin as quickly as possible in the newly diagnosed adult with Type 1 diabetes.  The correct treatment for Type 1 diabetes, at whatever age it is diagnosed, is exogenous insulin as early as possible, to control glucose levels, prevent further destruction of residual beta cells, reduce the possibility of diabetic complications, and prevent death from diabetic ketoacidosis (DKA). [4]

·         Appropriate education:  An adult who is newly diagnosed with Type 1 diabetes should receive Type 1 diabetes-specific education, not Type 2 diabetes education.  Type 2 diabetes is a different disease with different genetics, causes, treatments, and potential cures.

·         Autoimmune gestational diabetes:  Many if not most of medical professionals are not aware that gestational diabetes may be a precursor to Type 1 diabetes, not just Type 2 diabetes.  The stress of pregnancy is "the straw that broke the camel's back" for many women who develop Type 1 diabetes during pregnancy (autoimmune gestational diabetes).  Again, antibody testing can be used to distinguish autoimmune gestational diabetes, and women with autoimmune gestational diabetes should begin intensive insulin therapy immediately.[5]

·         Inclusion in appropriate statistics:  People with adult-onset Type 1 diabetes should be included in statistics addressing prevalence and incidence of Type 1 diabetes.  At the present time, most adult-onset Type 1s are included in figures for the numbers of Type 2 diabetics.   In information distributed to laypeople, the U.S. Centers for Disease Control and Prevention (CDC) and the American Diabetes Association (ADA) consistently say that Type 2 diabetes represents 90-95% of cases of diabetes in America and that Type 1 diabetes represents 5-10% of all cases of diabetes. However, this is incorrect according to ADA’s own peer-reviewed scientific journals. That 90-95% Type 2 statistic includes people with LADA, and according to the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus (as published in ADA journals), "Although the specific etiologies of [Type 2] diabetes are not known, autoimmune destruction of beta-cells does not occur."  The National Institutes of Health (NIH (NIDDK)) defines LADA as a condition in which Type 1 diabetes develops in adults.  Furthermore, the Expert Committee’s definition of Type 1 diabetes by the clearly encompasses all autoimmune diabetes, regardless of age, which includes LADA (“Type 1 diabetes results from a cellular-mediated autoimmune destruction of the beta-cells of the pancreas. In Type 1 diabetes, the rate of beta-cell destruction is quite variable, being rapid in some individuals (mainly infants and children) and slow in others (mainly adults).”)  According to Irl Hirsch M.D., member of the Expert Committee, “The term latent autoimmune diabetes of adults (LADA) as originally described represents perhaps as many as 10­ to 20% of adult-onset patients with diabetes.”  Doing the math, Type 1 diabetes represents about 20% of all people with diabetes.

·         Inclusion in clinical trials:  People with adult-onset Type 1 diabetes should not be excluded from clinical trials for Type 1 diabetes strictly because of age.  For example, Type 1 Diabetes TrialNet excludes many Type 1 diabetics and their families based on age at diagnosis.  Type 1 autoimmune diabetes is diagnosed based on epidemiology, not age; therefore, TrialNet is not truly representative of the full scope of Type 1 diabetes.  Former acting U.S. Surgeon General Dr. Kenneth Moritsugu, who was diagnosed with Type 1 diabetes at age 49, would be excluded from Type 1 Diabetes TrialNet.

All people with Type 1 diabetes deserve to be correctly diagnosed and be given disease-appropriate treatment, yet for many people with adult-onset Type 1 diabetes that is not happening today.

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[1] More recently, diabetes researchers have discouraged the use of the term latent autoimmune diabetes in adults, because LADA is not a latent disease.  One group has proposed the term ADASP (autoimmune diabetes in adults with slowly progressive beta cell failure), but this term seems cumbersome.

[2] Some adult-onset Type 1 diabetes is acute onset, similar to what most children experience.  I had acute-onset Type 1 diabetes.

[3] The U.S. Centers for Disease Control and Prevention’s (CDC’s) most current information on the prevalence and incidence of Type 1 diabetes comes from Diabetes in America, Chapter 3, “Prevalence and Incidence of Insulin-Dependent Diabetes” (Diabetes in America, Second Edition, 1995).  Although people who use that reference as a source of incidence statistics state that there are about 30,000 new cases of Type 1 diabetes each year and that half of those cases are children; in fact, that source states that children (<20 years of age) account for 13,171 cases and adults (>20 years of age) account for 16,542 cases, for a total of 29,713 new cases of Type 1 diabetes per year, 56% seen in adults.  Furthermore, that source states that there is an “unknown number of adults identified as Type 2 diabetes who have slowly progressive Type 1 diabetes.”  In summary, of those new onset Type 1 diabetics who are correctly diagnosed, 56% are adults, and an unknown number of new-onset Type 1 diabetics have been misdiagnosed as having Type 2 diabetes and thus the majority of new onset Type 1 diabetes is seen in adults.

[4] In the Diabetes Control and Complications Trial (DCCT), all subjects with adult-onset Type 1 diabetes had some residual beta cell function (Bernard Zinman MD, DCCT).  Those who were assigned to the intensive insulin therapy group were slower to lose residual beta cell function than the conventional therapy group (risk reduction 57%).  Clearly, early intensive insulin therapy has enormous benefit.  As demonstrated in the DCCT, “intensive therapy for Type 1 diabetes helps sustain endogenous insulin secretion, which, in turn, is associated with better metabolic control and lower risk for hyperglycemia and chronic complications.”  LADA researchers in Japan (Kobayashi et al, 2002) have conclusively demonstrated that better preservation of beta cell function occurs with exogenous insulin compared to sulfonylureas, and that sulfonylureas hasten beta cell destruction.  In other words, doctors may inappropriately use Type 2 therapies in new-onset Type 1 diabetes, but all scientific studies indicate that the correct therapy is intensive insulin therapy.

[5] In Europe, the literature on gestational diabetes mentions autoimmune gestational diabetes, but in North America the layperson literature doesn't mention it. However, the existence of autoimmune gestational diabetes is widely reported in North American scientific literature (for example, a July 2007 "Diabetes Care" article and also an April 2003 "Diabetes Care" article on GDM). The July 2007 issue of "Diabetes Care" indicated that autoimmune gestational diabetes (new onset Type 1 diabetes) accounts for about 10% of all Caucasian women diagnosed with gestational diabetes (Diabetes Care July 2007 vol. 30 no. Supplement 2 S105-S111 ). It says “A small minority (≤10% in most studies) of women with GDM have circulating antibodies to pancreatic islets (anti-islet cell antibodies) or to β-cell antigens such as GAD (anti-GAD antibodies)” and then notes, “They appear to have evolving type 1 diabetes that comes to clinical attention through routine glucose screening during pregnancy. Whether pregnancy can actually initiate or accelerate islet-directed autoimmunity is unknown.”

Melitta’s Top Ten Tips for the Newly Diagnosed Person with Adult-Onset Type 1 Diabetes

In no particular order:

1)    Despite what you may be told by medical professionals and what you might read, you (as a person with adult-onset Type 1 diabetes) are not “rare” or some “minority.”  Adults represent the majority of new-onset Type 1 diabetes--recent epidemiological data have shown that more than half of all new cases of type 1 diabetes occur in adults (Footnote 1). It is a widespread myth and falsehood that Type 1 diabetes is a childhood disease.

2)    Learn all you can, but at a pace that does not overwhelm you.  Good sources of learning are Think Like a Pancreas by Gary Scheiner (although he does perpetuate some myths about adult-onset Type 1 diabetes/LADA, but the rest is excellent) and my new favorite Bright Spots and Landmines:  The Diabetes Guide I Wish Someone Had Handed Me by Adam Brown of DiaTribe.  Sugar Surfing by Stephen Ponder and Kevin McMahon is diabetes management gold.  Using Insulin and Pumping Insulin by John Walsh are older but excellent, and the Type 1 University (https://type1university.com/) is a great source for learning specific skills. Taking Control of Your Diabetes (TCOYD) sponsors an annual ONE Conference that is outstanding. JDRF has a T1D Care Kit for newly diagnosed adults that is very good (JDRF Adult Toolkit). Be wary of the Internet—there is lots of good, but there is lots of very bad.

3)    Get a correct diagnosis:  many if not most people with adult-onset Type 1 diabetes are misdiagnosed as having Type 2 diabetes.  It is important to get a correct diagnosis to get the correct treatment (exogenous insulin); being treated as if you have Type 2 diabetes may be extremely harmful.  Get the full suite of antibody testing (Glutamic Acid Decarboxylase Autoantibodies (GADA), Islet Cell Cytoplasmic Autoantibodies (ICA), Insulinoma-Associated-2 Autoantibodies (IA-2A), Insulin Autoantibodies (IAA), and zinc transporter 8 autoantibodies (ZnT8) (Footnote 2).  Don’t just get GADA, because a small but significant percentage of people are GADA-negative but positive for one of the other autoantibodies.  Autoantibody testing is the gold standard test for Type 1 autoimmune diabetes:  if you are antibody positive, you have Type 1 autoimmune diabetes. [Note that although the vast majority of people with Type 1 diabetes are autoantibody positive, those with idiopathic Type 1 diabetes are not.  This could be because there are yet undiscovered autoantibodies, or some other reason.]  The c-peptide test, which shows how much insulin you are producing (virtually all children and adults with new-onset Type 1 diabetes are still producing some endogenous insulin), is useful, but does not provide a definitive diagnosis.

4)    Begin intensive insulin therapy as soon as you are able.  The correct treatment for Type 1 diabetes, at whatever age it is diagnosed, is exogenous insulin as early as possible, to control glucose levels, slow the destruction of residual beta cells, reduce the possibility of diabetic complications, and prevent death from diabetic ketoacidosis (DKA).  Many adults can prolong the “honeymoon” period (the time when some remnant beta cells are still producing insulin) with intensive insulin therapy (including using an insulin pump).  If a pump seems like too much or insurance will not cover one, MDI (multiple daily injections) is good.  Early insulin use and prolonging the honeymoon period will make it easier to control your diabetes and greatly reduce the risk of diabetic complications, thus making your life better.  Some people with very slow onset Type 1 diabetes may not need insulin immediately (Footnote 3).  But insulin should not be avoided due to fear.

5)    Allow yourself time and space to grieve.  The diagnosis of Type 1 diabetes is devastating for most people.  As an adult, you may wonder what you did wrong to precipitate Type 1 diabetes (the answer is nothing, it is an autoimmune disease).  Grieving often takes a lot of time, more time than we care to admit or allow, so it is important to give feelings of anger, denial, and depression their due.  Get the support you need from family, friends, online (TuDiabetes.org forums; some excellent Facebook groups), and a therapist (preferably one with knowledge of chronic illness) if you want.  JDRF has groups for adults. Do things that bring you joy and well-being:  exercise, yoga, meditation, gardening, petting dogs/cats, music, etc.  Remember you have been given a second chance at life; make it count.  Balancing Diabetes:  Conversations About Finding Happiness and Living Well by Kerri Sparling has great tips for living better.  Diabetes Sucks and You Can Handle It: Your Guide to Managing the Emotional Challenges of T1D by Mark Heyman, a psychologist and person with T1D, is excellent; Dr. Mark also has a podcast. An older book that I think is excellent is Psyching Out Diabetes: A Positive Approach to Your Negative Emotions (Rubin, Biermann, and Toohey.  1997). The Behavioral Diabetes Institute (http://behavioraldiabetesinstitute.org/) is also superb in this area.

6)    Consider the wise advice of people at the Behavioral Diabetes Institute:  maintain the best blood sugar control you can, avoid lows (hypoglycemia) especially severe lows, and live your life.  Don’t think that a cure for Type 1 diabetes is coming anytime soon.  If you are a Type A personality, be especially wary of being harsh on yourself for some number on a meter/CGM and be wary of trying to achieve some “perfect” A1c.

7)    Test, test, test.  Lots of blood glucose testing means better control.  If you can, get a continuous glucose monitor (CGM), which in the case of Dexcom gives a blood glucose reading every 5 minutes, and also lets you know what direction your blood glucose is trending.  Don’t allow embarrassment to prevent you from taking proper care of yourself (meaning, if you need to test or inject in public, do it.)  Eat to your meter (use your blood glucose meter/CGM to test your blood sugar after meals and eliminate from your diet the foods that spike your blood sugar).  Follow the rule of small numbers (from Dr. Bernstein:  big inputs make big mistakes; small inputs make small mistakes—in other words, lower carb means lower doses of insulin means smaller “mistakes”). 

8)    Get organized; get your security blanket in order.  For me, security comes in the form of backup—I carry my diabetes kit with me at all times.  My diabetes kit includes insulin vial and needles, meter and test strips, glucose tabs, and backup supplies for my insulin pump.  I wear a Medic Alert (www.medicalert.org) bracelet that says I have Type 1 diabetes, an insulin pump, and that I have autoimmune hypothyroidism (Hashimoto’s disease).

9)    Use your healthcare team.  Find good people who you can work with and who work with you as an individual.  Your team might include an endocrinologist, diabetes care and education specialist (DCES), nutritionist, and psychologist. Be your own best advocate in the healthcare system.

10) Get tested for Hashimoto’s Disease and celiac disease, two autoimmune diseases that are commonly seen in people with Type 1 autoimmune diabetes.

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Footnote 1:  R David Leslie et al. Adult-Onset Type 1 Diabetes: Current Understanding and Challenges. Diabetes Care 2021;44:2449-2456..

Footnote 2:  IAA test does not distinguish between autoantibodies that target the endogenous insulin and antibodies produced against exogenous insulin. Therefore, this test is not valid for someone who has already been treated with injections of insulin. For example, someone who was thought to have Type 2 diabetes and who was treated with insulin injections cannot then have this test done to determine if they have Type 1 diabetes.
Footnote 3:  Some people whose Type 1 diabetes is slowly progressive and is caught early can go without exogenous insulin for a time (however, insulin should not be avoided due to fear, either on the part of the person with T1D or his/her/their doctor).  Dr. Anne Peters, the acclaimed endocrinologist and co-editor of The Type 1 Diabetes Sourcebook, is positive for four autoantibodies, although she does not yet have symptomatic Type 1 diabetes.  Dr. Peters is using liquid metformin and Ozempic (a GLP-1 receptor agonist) to try to preserve her beta cells.  Also, a recent study (IK Hals et al, Diabetes Obes Metab 2019;1-9) found that exogenous insulin and the DPP-4 inhibitor sitagliptin worked equally well to preserve beta cell function in people with slowly progressive Type 1 diabetes (note that the older insulin, NPH, was given once a day in the insulin arm of the study, meaning 24 hour coverage with exogenous insulin did not occur).  For those that are not on exogenous insulin, it is a good idea to have some on hand in case one's blood sugar rises rapidly due to illness, etc.