What's the Risk of Type 1 or Type 2 or Type 1.5?   (June 16, 2013)

Recently, the question was asked:

“I was diagnosed at the age of 14 with Graves’ Disease (autoimmune hyperthyroidism); at age 26, I received a diagnosis of Rheumatoid Arthritis. My mother is a diabetic, her parents and 3 out of her 4 siblings were diagnosed with diabetes (type 2, insulin dependent). Now at 42, my doctors are saying that I may become diabetic. My dad had thyroid, and his mother was a diabetic, thyroid, and severe rheumatoid arthritis patient at an early age. I know I have a strong possibility of becoming a diabetic, but my question is this, it seems like it may be possible for me to be susceptible to Type 1 (due to autoimmune problems) or Type 2 (genetic). Or is there the possibility of Type 1.5?"

My reply:

Your physician is correct, that you have a strong possibility of developing diabetes. But, as you are aware, guessing what type of diabetes it might be is difficult.

You might develop type 1 diabetes, as you have other autoimmune disorders. The combination of autoimmune disorders is called by several names, including “autoimmune endocrine failure syndrome” and “polyglandular autoimmune syndrome” and includes (among other disorders) type 1 diabetes, Graves' disease (autoimmune hyperthyroidisim), Hashimoto’s thyroiditis (autoimmune thyroid failure), Addison's disease (autoimmune adrenal gland failure), vitiligo (patches of white skin associated with autoimmune findings), alopecia (hair loss), hypogonadism (failure of sex gland function), and pernicious anemia (which is an autoimmune form of anemia). This collection of disorders has specific HLA (human leukocyte antigen) findings and each of the disorders have specific antibodies that can be measured. So, although it’s not commonly done, you could have HLA testing to see whether you are at extreme risk, or organ-specific antibodies could be measured (See Polyglandular Autoimmune Syndromes: Immunogenetics and Long-Term Follow-Up for details). Please note, these autoimmune failure syndromes are hereditable, so it’s possible that your dad’s side of the family might have the tendency for the syndrome and pass it along to you.

Or you might develop type 2 diabetes, as your mom’s side of the family seems to have considerable type 2 diabetes, and type 2 is highly hereditable. Type 2 diabetes is not associated with standard diabetes antibodies, so if you are tested for diabetes antibodies and the results are negative, it would shift the odds for any future diabetes towards type 2.

As you know, there’s a unofficial term for another type of diabetes that goes by the nickname “type 1.5 diabetes.” There’s no clear definition for “type 1.5,” but it’s not a fifty-fifty mix of types 1 and 2. Some people consider “type 1.5 diabetes” to be an alternate term for LADA (latent autoimmune diabetes of adults), which is an autoimmune form of diabetes that shows up in adults. People with LADA are diagnosed with what initially appears to be type 2 diabetes, and then rapidly progress to insulin-dependency.  Diabetes antibodies are present, which is usually considered a hallmark of type 1 diabetes.

I can’t predict which of these three types of diabetes might be in your future. But you do seem at high risk. As such, there is some standard advice that you should be aware of to help decrease your chances of diabetes (and were you to be diagnosed with any kind of diabetes, they’ll all definitely on the list of things to do, so you might as well get started now). These include:

• Eating right (Yes, I know that’s a bit vague! You might want to set an appointment with a diabetes dietitian to review your meal planning)
• Getting regular exercise
• Avoiding obesity (and losing weight if overweight)
• Quitting smoking
• Aspirin therapy – check with your physician
• Aggressive control of high cholesterol and hypertension if present
• Getting a flu shot every autumn

Also, your physician should plan to check your blood glucose anytime that other lab tests are ordered, especially as stress associated with acute illness tends to raise the BG level. Your doc should also order an A1C test every year or thereabouts (see Recommendations on screening for type 2 diabetes in adults ) to see if you are developing prediabetes or diabetes.

Hope this helps!