How does a doctor differentiate between Type 2 and Type 1.5 LADA?

I’m just curious, and I’m having a hard time understanding exactly what the difference is between the two. And if so many cases of Type 1.5 are misdiagnosed as Type 2, how does the Dr. know for sure? I’m assuming one difference is Type 1.5 is an autoimmune disease and Type 2 isn’t, but not sure what an autoimmune disease is and how its connected with diabetes. Perhaps someone can put it into laymen’s terms where I can understand.

Autoimmune disease is when the body immune system which was made to protect the body against bacteria and viruses by starting a cascade of reactions to halt their effect and protect the body,is disrupted and start attacking the self as forign.So antibodies will attack islet cell in Pancreas,or throid tissues or other organs.Why this happen,there are some theories but still not completely know why,though it is known how.
Type2 diabetes is a kind of exhausted Beta cells with much insulin produced over time but not doing its job,so increasind daily activity,or reducing some of abdominal fat,if present may improve insulin work,if not,medicine or insulin are added to normalise blood glucose.

So what kind of tests would my Dr. run to find out if what I have is Type 2 or possibly Type 1.5? How would he determine that?

Type 1.5 is type 1 autoimmune diabetes with onset during adulthood.
Gad antibodies,islet cell antibodies… For autoimmune type1 diabetes,the problem is there is type1b,non autoimmune according to ADA classification of type1.Excluding autoimmune type is important so you do not have to screen for other autoimmune diseases periodically.Type2 insulin resistance.fasting c peptide& insulin are usually done.
There are very rare other types ( MODY).

The tests are a C-peptide test to see how much insulin is being produced & an antibody test. Are you responding to your oral meds? Some people produce sufficient insulin, but their bodies don’t utlize it well. They’re insulin resistant. Type 1’s have very little insulin production, if any.

I had to leave the oral meds behind some time ago. I started out on Lantus, then Levimir, then Novolog, and Humulin. I was taking between 200 and 300 units a day. I have been on the pump now for about 6 weeks or so. This is the first time in a year that my blood sugar is down in the low 100’s. I am currently averaging probably 110 units of Humalog a day on the pump. So, I don’t know. I guess I will question my Dr. when I go back in.

Doesn’t sound like you’re Type 2 if you’re taking that much insulin. Congrats on better numbers & less insulin on the pump. That’s great!

An easy way to think about it is a Type 1’s body produces no insulin because the body attaced the pancreas thinking it was a foreign body like a virus. This person will require insulin shots the rest of their lives and oral medications will not work.

A Type 2’s body still produces insulin, but their cells do not take up insulin effectively. Think of insulin as a key that unlocks a cell to allow suger in for energy. Type 2’s have cells that have less key holes to unlock the cells. Type 2’s are most often overweight and I think of the cells as being goopy like being coated with honey and the key holes are covered up.

A Type 1.5 is usually an adult who is diagnosed later then what is considered normal for Type 1 (we used to call it juvinal diabetes because it was usually kids who got it), but has symptoms of Type 1 and Type 2. The doctor can do a test to see how much insulin the body is producing still and help him with the diagnosis. These patients will still benefit from oral medications, but may require insulin to cover their meals. If your insulin production is too low your own body will not be about to produce enough insulin to cover your meals. Study’s have shown that more and more people are being diagnosed with Type 1.5 and doctors know quite well what you have due to test that are available.

Hope this helps.

Type 1.5 is often misdiagnosed as Type 2 because the diagnosing doctor (usually a general practitioner) is not familiar with LADA and does not run the appropriate tests – if you’re over 25 and have the basic symptoms of diabetes (or read high enough blood glucose or A1c, or show impaired glucose tolerance on an Oral Glucose Tolerance Test) you’re automatically “T2” in their eyes.

The basic tests to determine diabetes (general) are the basic glucometer blood test, often followed by a standard metabolic panel (liver and kidney functions, fructosamine, HbA1c). Elevated blood glucose or HbA1c will be taken either as a definitive diagnosis (especially if in the presence of other issues associated with metabolic syndrome), or a diagnosis may be confirmed with an Oral Glucose Tolerance Test (OGTT) and/or additional blood tests – such as the C-peptide test, islet antibody tests, GAD antibody tests, and possibly tests for specific genetic markers. These are often only run when oral medications are not effective; they sometimes do not show “autoimmune diabetes” markers at the earlier stages of the disease (aka “honeymoon phase”).

When Type 2 diabetes is suspected, the doctor should run both an OGTT and check for plasma insulin levels. High plasma insulin levels suggest insulin resistance (IR), which needs to be counteracted by diet and exercise, weight loss (if appropriate), and sensitizing pharmaceuticals such as metformin, Avandia, Actos, etc. If the OGTT suggests impaired glucose tolerance (IGT) and insulin levels are low (no obvious IR), then insulin secretagogues such as sulfonylureas (e.g., glipizide) may be a more appropriate first-line therapy. In the case of IGT without obvious IR, c-peptide and antibody levels should be checked regardless of diagnosis to determine level of beta cell exhaustion.

Unfortunately, standards of care do not currently request physicians look for the particular cause of any of the general classifications of diabetes (“Type 1, Type 2, Gestational”) or any presentation that falls under the general “diabetes” header – much less tailor first-line therapy to the causative factors. Many of our community with LADA have had more than a year of trial and error until appropriate diagnosis and therapy were begun.

I was treated for Type 2 for a few years with little success, thats when my endo ran the extra tests and found that I was Type 1.5 LADA and that I could lose all the weight I wanted, execise all day and take all the pills I wanted and I would still need insulin. Its was a relief to get a definate correct diagnosis, because now I know what needs to be done.

Actually it’s quite the opposite. Type 1 (and 1.5) generally don’t have insulin resistance, or least not much, so we typically take less insulin than a type 2. Type 2s have trouble using the insulin so can need 10 times as much for the same job.
I can use just 2 or 3 units for the same meal a type 2 could take 40 units for.

Even a type 1 can have insulin resistance though - and we all get it when our blood sugars are high. So you can’t be sure what’s going on until the BG has been within normal range for a while.

Thanks for the advice. I have had this disease for 3 years now, and I still don’t completely understand it. I have learned more since the Dr. put me on the pump and I discovered this website than I ever have before.

Thanks for the info Chelsea. I like the analogy of the key unlocking the cells. That makes it a little easier to understand.

Hi Bobby,
This video may help shed some light on the topic:

Wow! Thank you for asking these questions, Bobby!

So many great responses from this community. It’s very helpful!!

Thanks everyone.

Great video, Manny!!

Adult-onset Type 1 diabetes (often called Type 1.5 or LADA) is misdiagnosed as Type 2 usually only because of the age of the patient, certainly not because of etiology. Of course, the other major reason for misdiagnosis is the ignorance of the medical community about the prevalence of adult-onset Type 1 (it is two to three times more common than childhood-onset Type 1). The definitive test for Type 1 autoimmune diabetes (at any age of onset) is antibody testing (glutamic acid decarboxylase antibodies (GADA), islet cell antibodies (ICA), and insulinoma-associated (IA-2) autoantibodies). If the person is antibody-positive, he/she has Type 1 diabetes. C-peptide is also a useful test. Antibody testing of newly diagnosed diabetics is the only way to reliably determine if the person has immune-mediated diabetes or not. Often, doctors claim that antibody testing is too expensive—but the out-of-pocket expense to a patient is $479! Any diabetic complication is far more costly than that trivial amount. Type 1 diabetes and Type 2 diabetes are two completely different diseases with different causes, genetics, treatments, and cures. Exogenous insulin is the appropriate treatment for Type 1.

I Love this thread. My Husband was diagnosed with Type 2 diabetes years ago (about 8 I think) and he is now on insulin, Januvia (sp), and some others for cholesterol and aspirin. He has a family history of Type 2 which was un-noticed until he got diagnosed. He has progressed from only oral meds to needing insulin. He is not horribly overweight. He is somewhat, but he is by no means obese. (I personally feel he is not overweight enough to be type 2 and feel that even if he did loose the weight he would still be diabetic). After coming to this site w/my daughter being diagnosed type 1 (He is not her biological father), I have asked him to have his new Endo run more tests to see if his pancreas is even functioning. Even if it was a few years ago, it might not be now. Is this theory right? Am I right in wanting the extra tests run? He recently was told by the new Endo that the nerves around his heart are numb and he could have a heart attach and not know it. He also told him to switch jobs and or ask for a different shift due to stress.

If you’ve been diagnosed T2, as it looks like many of you initially were…at what point do you tell that the medicine is not working? How much oral meds should you consider taking b/f you decide that route isn’t working? I have highs at 1 hour post prandial around 200, but then at 2 hrs. I drop to a range typically between 120-140. Does this sound like my medicine is working, since it drops back down at the 2 hr. point? I’ve noticed that my fastings are starting to creep up (fasting #'s were my good #'s in the beginning!) and my overall post prandial is creeping up as well. I am on Janumet 50/500. I have tried taking this dose twice daily and it really upsets my stomach. Do I need to try a different med or try to deal with the side effects and up the dosage? I have an appt. on Friday and am going to ask to get the blood work to rule out LADA since I kind of suspect that may be the case…but, I have to wait. I just want to know—how do you determine that your oral meds aren’t working? Thanks in advance for any advice!!

I am a member of and we’ve had several cases recently of T1 (probably T1.5) being misdiagnosed asT2.
T1.5 is a T1 type. The person is no longer making their own insulin and will always require insulin therapy.
A very important difference between the 2 types, is the speed at which things go wrong. Becauese T2s usually still have some insulin response, blood sugar climbs more slowly and therefore DKA( diabetic ketoacidosis) is extremely rare. In the cases we have been told about, when the patients were told that they were T2, the BG levels were extremely high.( over 20 or 360) That would be very rare in a new T2, so the doctors should have suspected T1 or T1.5, just from that one figure. When asked for advice, I always tell people who are adult and presented with a BG of over 20 to go straight to the emergency sevices if they feel ill.
I problrm is that even the doctors are being trapped by “the Blame Game”. If you develop diabetes as an adult, it must be your fault for living an unhealthy lifestyle and it must be T2, because only kids develop T1.
A couple of these folks who have written to us have ended up in hospital with life threatening DKA, because of mis-diagnosis. This being Britain, the doctors don’t get sued. They SHOULD get reprimanded. I feel, but even in 1 case where the emergency doctor sent a sick patient home, who ended up being an emergency admission a few hours later, because she was “Only a T2” wasn’t censured.

can anyone tell me what the normal range is for the c-peptide?