May 2, 2008

Type What?

A study published in the most recent edition of the journal Diabetes makes it even more clear that the usual division of diabetes into "Type 1" and "Type 2" is an oversimplification.

The usual mythology has it that Type 1 is an autoimmune disease and people who get it are innocent bystanders while Type 2 is caused by overindulgence and people who get it should be ashamed of themselves.

I've written at length about why the second part of this formula is bull crud. You can read the many reasons HERE.

But there is no question that framing the diagnosis of diabetes this way has made many people with autoimmune forms of diabetes hostile to those with Type 2, because they feel that an ignorant public unfairly blames them for causing their condition and believe, with the rest of that ignorant public that those gluttonous lazy type 2s do deserve such blame.

But the latest research on LADA, the adult onset form of autoimmune diabetes, has come up with a finding that makes it clear how wrong this kind of thinking is. The researchers in this study, which you can find at the Diabetes web site:

Autoimmune Diabetes in Adults, Type 1 Diabetes, and Type 2 Diabetes

examined the genes of 361 peole with LADA, 718 people with type 1 diabetes, and 1,676 type 2 diabetic patients, as well as 1,704 healthy control subjects from Sweden and Finland.

They found that "LADA subjects showed, compared with type 2 diabetic patients, increased frequency of risk for the HLA-DQB1 *0201/*0302 genotype with similar frequency as with type 1 diabetes (36%)." There were some other similarites with Type 1, genetically, but then they also found that "the frequency of the type 2 diabetes–associated CT/TT genotypes of rs7903146 in the TCF7L2 were increased in LADA subjects (52.8%; P = 0.03), to the same extent as in type 2 diabetic subjects (54.1%, P = 3 x 10–7), compared with control subjects (44.8%) and type 1 diabetic subjects (43.3%).

In short, these LADAs had both type 1 genes--autoimmune genes--AND type 2 genes.

This finding is particularly interesting in light of an earlier finding that slightly under 10% of people diagnosed with Type 2 also have autoimmune markers like elevated GAD antibodies.

TCF7L2 is one of the more common defective genes found in Type 2 diabetes but by no means the only one. HNF4-a is another gene that has been found in association with both a form of MODY and with a Type 2 diabetes in both Ashkenazi Jewish and Danish populations.

In addition, as they get older, many Type 1s find their insulin needs rise, as they become insulin resistant and probably start expressing the Type 2 genes they inherited. Doctors do not give Type 1s who are using larger doses of insulin metformin, but my guess is that they probably should. I'm not very insulin resistant at all--two or three units is all it takes to drop my blood sugar dramatically, but even so, I can drop my insulin needs by about 1/3 by taking metformin. But here again, the division of diabetes into these two artificial types is hurting people because doctors do not think that a "Type 1" might also have the genes that in middle age would have expressed as "Type 2" had they not also suffered an autoimmune attack.

So it is time we dispensed with the artificial division of diabetes into Type 1 and Type 2. Let's admit that "Diabetes" is really nothing more than a symptom--high blood sugar--and that the causes of that symptom are many and not mutually exclusive.

When the damage is to the immune system, we get autoimmune attack on the beta cells. When the damage is to the genes that regulate insulin resistance in the muscles--and possibly mitochondrial function, we get another form of diabetes, when the damage is to the genes that regulate the beta cell's response to rising glucose levels in the blood we get secretory defects, when the body suffers genetic damage thanks to exposure to chemicals in the environment we get yet more blood sugar abnormalities, and like the unlucky LADAs, some of us get more than one of these problems going on at once.

And those of us who do have abnormal glucose metabolism should resist the temptation to divide people with diabetes into types and to use this typology to define some of us as blameless and others as blamable diabetics.

That kind of division helps no one. All of us should be putting our efforts into ensuring that EVERY person with diabetes gets the kind of excellent, health-preserving treatment that so few of us currently get from the doctors, nutritionists, and drug companies who see us as little more than a huge profit center.

7 comments:

Anonymous said...

"All of us should be putting our efforts into ensuring that EVERY person with diabetes gets the kind of excellent, health-preserving treatment that so few of us currently get from the doctors, nutritionists, and drug companies who see us as little more than a huge profit center."

I agree with the above statement. But, I must say, "excellent, health-preserving treatment" is not the same for Type 1 and Type 2.

Even my small son (who has Type 1) understands that. His great-grandmother and his grandfather both have Type 2. He never sees them check their sugar. He never sees them look at the back of the box for carb counts. He knows it's because they really don't have to like he does.

My dad's latest A1C without hardly ever checking sugars or counting carbs, 5.7. My son's latest A1C,after counting every carb that goes in his mouth and checking his sugar 10-12 times a day, 7.2.

I'm not saying that Type 1 is worse than Type 2 or vice versa. In fact, since Type 2 is in my family I do not look forward to the day that I will probably develop it too.

What I'm saying is don't say that those of us who want Type 1 and Type 2 seperated want it done because we don't want ourselves or our children blamed for their disease. I don't feel that way at all.

I think it does a disservice to those with Type 2 as well as those with Type 1 to lump us all together. I don't want my son mistaken for someone with Type 2, not because of stigma, but because how he should be treated (medically) is not the same as someone with Type 2.

My son could go into DKA if his pump malfunctions and it goes unnoticed for several hours. That's not going to happen with Type 2.

It's important for me as a mother because most people know someone with Type 2. They know that they check their sugars, but certainly not 10-12 times a day. So, I get looked at like a monster when they find out that my son does that. They think it's overkill. It isn't. It's a neccesity.

But, they draw on their experiences with Type 2 when they meet my son. They think he's at death's door because he wears an insulin pump.

That is why I explain over and over the difference between Type 1 and Type 2 (because there is a difference). It's not because I don't want my son lumped into the category of "people with diabetes brought it on themselves". It's because when they see that insulin pump on his side, or see me sifting through the trash to find the box for carb counts, or see me check his sugar a couple of times in a few hours, they don't think I'm being an overzealous mom. I want them to realize that it's something my son has to do to survive.

I'm sorry to be so long-winded. Thanks for listening.

Scott S said...

I believe that the terminology used should be abandoned, but try convincing the authorities at the American Diabetes Association, they still advise high-carb, low-fat diets for people with diabetes, and are recommending statins for everyone!

Still, one item this study did not address was the fact that we have seen a number of studies linking "human" insulin to autoantibodies, further blurring the already fuzzy lines. But the real issue that needs to be resolved is that the focus must be shifted away from chronic treatment to eradicating the disease -- something which the discovery of insulin almost 90 years ago effectively killed.

Lili said...

Some doctors do give insulin resistant Type 1s metformin, but it seems to be very few. I agree that they probably should do it more often.

If not a mother... said...

My type 1 husband reached his heaviest weight a few years ago and definitely had some major insulin resistance going on. And whaddya know, he has type 2 in his family (as well as type 1), though none of the relatives who had it were overweight by any means. Things improved as his weight was lowered, but it was scary how much it took to bring a high down.

Anonymous said...

I know the onset of LADA is much later than typical type 1s, but how fast is the development once it starts?

Jenny said...

Re the speed with which LADA develops I read recently that it usually takes four years for someone with LADA to progress to complete insulin dependence.

Jenny said...

Linda,

Much of the advice on the site you mentioned is outdated.

Soy can be very hard on your thyroid and the worse your thyroid function, the higher your cholesterol.

But the point of these studies is that cholesterol is NOT the problem and lowering it does NOT improve heart health.

When you lower your blood sugar by cutting carbs and decreasing insulin usage your cholesterol will lower naturally but it is the high blood glucose that appears to be causing the heart disease and raising the cholesterol--probably by clogging receptors in the molecules that are supposed to remove LDL from the circulation.

Most people who cut down dramatically on carbs see their cholesterol improve within six months and that is while eating high fat diets.

But to reiterate, the data is making it clear that, as Gary Taubes documents so exhaustively, high cholesterol does NOT cause heart disease and lowering cholesterol does not prevent heart attack death.

It's that simple.