Ask An Expert: Late Onset Diabetes Type 1

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Ask An Expert: Late Onset Diabetes Type 1

Question:

What is "late onset" diabetes type 1?

Answer:

Diabetes previously was classified based upon the age it began: adult onset diabetes or juvenile onset diabetes. These terms are no longer used by most doctors. Although they helped doctors to classify most people correctly in the past, earlier onset of type 2 diabetes is becoming more prevalent, and sometimes type 1 diabetes occurs beyond adolescence.

When diabetes develops in a mature adult (for example, an adult who is older than 50) or an adult who is overweight, it is usually type 2 diabetes. Type 2 diabetes results when the body becomes resistant to the effects of insulin. The pancreas may work so hard to produce extra insulin that it eventually becomes damaged. Still, the main problem in type 2 diabetes is the body's resistance to insulin. Type 2 diabetes usually (but not always) first appears during adulthood.

On the other hand, when diabetes develops at a young age, most of the time it is type 1 diabetes. Type 1 diabetes usually occurs after the immune system forms abnormal antibodies that attack and damage the pancreas, so very little insulin can be produced.

It is possible for adults to develop type 1 diabetes (diabetes caused by an autoimmune attack on the pancreas), although type 1 diabetes is less likely to begin in adulthood than it is to begin in childhood or adolescence. This is what is known as "late-onset type 1 diabetes." It is also known as "adult-onset type 1 diabetes" or "latent autoimmune diabetes in adults" (LADA). It is possible to identify late-onset type 1 diabetes by checking for antibodies in the blood to verify that the immune system is attacking the pancreas.

Determining whether a person has type 1 or type 2 diabetes allows doctors to make better decisions about diabetes treatment. For example, most adults with type 2 diabetes can initially be managed with diet, exercise and oral medications. An adult who develops type 1 diabetes is not likely to get good control of blood sugar levels with oral diabetes medicines alone, so insulin is required.

Mary Pickett, M.D., is a lecturer for Harvard Medical School and an assistant professor of medicine at Oregon Health & Science University in Portland, OR. At OHSU, she practices general internal medicine and teaches medical residents and students.

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Last updated:	January 24, 2007