Causes of LADA

My endocrinologist made a point of telling me “it’s not your fault” three times in my first visit……well what causes LADA at age 72? I think eating and obesity can be factors in cause. I was diagnosed Type 2 for over a year and wonder if all those meds I was prescribed delayed or made it worse. Metformin, Actos, Rybelsus, can’t remember them all.
My dietician advised I get the C-Peptide test and confirmed antibodies are destryoing my pancreas. After 71 years??? Any ideas on cause of type 1 after after age 70? Doc thought was environmental or food supply.

There are about 4 genetic variants that increase the risk of contracting type 1 autoimmune diabetes mellitus, HLA DR 3,4,7 & 9. Having these variants does not guarantee that one will become a T1DM. It appears that a trigger, often a viral infection, causes the immune system to misidentify the insulin secreting Beta cells as foreign invaders and begins destroying them.

When this happens in the young the destruction of Beta cells and loss of insulin secretion is usually rapid. This is not the case for adults where the loss of Beta cells tends to be slow. The combination of slow progression with the age of the patient often leads to a misdiagnosis of type 2 insulin resistant diabetes mellitus.

If the person is also obese this makes an error in diagnosis more likely. One thing the obesity may be a symptom of insulin resistance. If there are one of the antibodies associated with T1DM the person may have type 1 diabetes mellitus with insulin resistance. This condition was formerly called double diabetes.

The T2DM drugs you were taking or obesity did not cause you to contract LADA T1DM. The drugs may have been slightly effective early on, but as insulin production decreases, injecting or infusing insulin is necessary.

It’s not nice that we have to deal with increasing health problems as we age. I am 74, T2DM for 34 years, currently on a pump and using Metformin. I remember the first decade when I could manage with diet and exercise. Those days have passed. I still am careful about diet and exercise daily, but my Beta cells wore out from years of combatting insulin resistance of my body’s cells.


Hereditary predisposition may be another cause, precipitated by some other event such as trauma of some sort. I came down with T1 at age 62, exactly the same age as my maternal grandmother. But this was about 10 years after I’d had hand surgery for a cat scratch that threatened amputation of the hand. This was followed by 4 days in hospital with a constant antibiotic drip and then 10 more at-home days of oral antibiotic. I suspect the antibiotic killed off most of my intestinal biome and what grew back was skewed. I, too, was first misdiagnosed as a T2 because of age. But an endo whom I consulted ran a GAD65 as well as several other tests and immediately prescribed insulin. I am now 83 years old and still going strong… Diabetes de damned! BTW, the hand surgery was extremely successful and I don’t even see a scar on my knuckle.


The prevailing theory is a virus sets it off in most cases. There are some possible completely unknown causes. But they have identified several genes that make you predisposed to getting it. Then probably a virus, several different viruses, sets off the wrong immune response. Covid is one of those viruses that can cause Type 1 or type 2. They know one of the childhood vaccines lessens the risk of getting type 1 and there are several research studies working on the vaccine theory and possible vaccines. And they have identified 9 genes last I heard so far, many of them immune genes. But 50% of cases are diagnosed after the age of 30.

We are often misdiagnosed, one reason that helps that is because it is slow onset as an adult. We make some insulin for many years, sometimes over 8 years plus before you stop completely or stop enough that your body can’t cope enough. But misdiagnosis is still way too common. There is just a huge gap in knowledge of doctors about Latent Autoimmune Diabetes in Adults. It wasn’t that many years ago that I was told if I was a type 1, drugs wouldn’t work at all on me. But drugs do work for a while because you still make some insulin. I had another doctor question whether i was type 1 because I didn’t get it as a kid. Unfortunately that huge lack of knowledge out there puts a lot of us at risk.

Whether you get type 1 at any time, inheriting the “right” genes and getting the “right” virus seems to be the most prevailing common cause. You are lucky your dietician recommended testing, I was misdiagnosed for over 8 years. I had already been put on insulin before the proper diagnosis because the different drugs made me sick


I go with the belief that heredity plays a big part in T1 development but not always. Many T1s are the only ones in their families. Also I believe that viruses are the culprits. My personal experience has been a combo of both. I am the oldest of three children. My youngest brother was diagnosed when he was 3 years old. He always seemed to have a cold. He echoes what many of you have testified about the old ways of testing blood sugar. He is 56 now. My other brother was incorrectly diagnosed at age 40, but that didn’t last long and was quickly relabeled correctly as T1. He had been sick previous to diagnosis. He is now 66. Then there is myself. Full blown DKA at age 57 also after being sick. I am 68 now. So to close, family get togethers often involve conversations about how we deal with it. :grinning: