I am raising my voice for Type 1 diabetes, although I admit this content has appeared before. I think it's important, though. It's about LADA (Latent Autoimmune Diabetes in Adults).
This information comes from research, but mainly from experience and reports from out "in the field."
LADA is autoimmune diabetes just like regular Type 1, but it is often misdiagnosed as Type 2. That's because it occurs in adults over 25 and because the onset can take 6-8 years. (While regular Type 1 can occur at any age, the onset is sudden).
How to tell the difference between LADA and Type 2:
- Positive antibody test -- while a negative antibody test is not conclusive, a positive result indicates Type 1 or LADA.
- Weight -- Type 2s on the thinner side are very uncommon except in certain genetically susceptible subgroups of Native Americans, Asians (South Asians, Japanese), Hispanics, Scandinavians, and African Americans. It would be unusual for someone very thin or underweight, and/or in great athletic shape to develop Type 2.
- Family history. Someone with a long family history of diabetes is more likely to have Type 2, although it could be argued that many of these could be unrecognized cases of MODY.
- Weight loss -- Unexplained weight loss before or around diagnosis is associated with Type 1 or LADA, not Type 2.
- Ketones -- Moderate or high ketones are rare in cases of Type 2 and generally only occur in people who have had Type 2 for a very long period of time and no longer make insulin. Moderate or high ketones at diagnosis tend to indicate Type 1 or LADA.
- Progression to insulin -- LADA results in insulin dependence much sooner than Type 2, even within a year of diagnosis. This is working from the outmoded belief that insulin should be prescribed when it's no longer avoidable, though.
- Response to oral medications -- LADA does not respond well, or for very long, to medications used to treat Type 2.
- C-peptide -- This level will decline rapidly as compared with Type 2. In some people in the very early stages of LADA, C-peptide may actually be elevated and seem to indicate Type 2. However, the ensuing quick decline in C-peptide is indicative of LADA.
- Insulin resistance -- LADA is not associated with insulin resistance, although see C-peptide.
- Triglycerides and blood pressure -- these are usually elevated with Type 2, but not usually with LADA.
- Low carb doesn't work -- Assuming none or only moderate overweight, going on a low carb diet does not work to control blood sugars.
- Hypoglycemia -- anecdotal evidence suggests a history of hypoglycemia prior to diagnosis might be associated with LADA.
- Inconsistent blood sugars -- The honeymoon phase in LADA can last several years. During this time, the beta cells often work or not work somewhat intermittently.
Why does it really matter if it's LADA or Type 2?
- Seriousness -- Sadly, Type 1 is often treated more "seriously" and aggressively by doctors and insurance. It can be difficult to get adequate treatment or have insurance pay for the right treatment unless one is classed as a Type 1 rather than a Type 2 (insurance companies only believe in two types of diabetes). Insurance companies will often only cover insulin pumps for Type 1.
- Treatment -- People with LADA should be treated like early Type 1s, not like Type 2s. Early treatment with insulin is believed by many to reduce the workload on the beta cells and preserve their function longer. This is important because retaining some insulin production for as long as possible reduces hypoglycemia and the risk of DKA. Also, background insulin can for most reduce the unpredictability of the beta cells working intermittently.
- Danger -- LADA is subject to the same dangers as Type 1. A few people are diagnosed in DKA (usually as Type 1), but after treatment have a sort of "remission" due to the extended honeymoon period. Still, DKA can occur on rare occasions if insulin production suddenly stops.
So how can I tell if I have LADA instead of Type 2?
- positive antibody test (you can stop now) or low C-peptide?
- quite thin or active and in good shape?
- unexplained weight loss?
- no insulin resistance?
- have you had moderate or high ketones?
- low triglycerides and normal blood pressure?
- high or variable blood sugar despite oral medications and/or low carb diet?
- quick progression to insulin?