Diabetes Health Center

Type 1 Diabetes Prevention

If you don't smoke cigarettes, you greatly reduce your risk for lung cancer and emphysema. If you maintain a healthy weight, eat a moderate diet, and get regular exercise, you greatly increase the chance that you'll have a healthy heart.

But if you're at risk for developing type 1 diabetes due to a family history of the disease or other factors, is there anything you can do to stop it? The answer is a definite "maybe."

Diabetes experts now recognize that type 1 diabetes is an autoimmune disease, in which the body's immune system for some reason turns on itself and begins to attack and destroy the beta- islet cells of the pancreas that produce and release insulin. When enough beta islets are destroyed, the body cannot produce enough insulin to properly regulate blood sugar, resulting in type 1 diabetes.

Because type 1 diabetes is caused by a normal immune system gone awry, researchers believe that it may be possible to step in and either prevent, interrupt, or at least slow down the disease-development process. Result thus far, however, have been mixed at best.

Diabetes Prevention Trial - type 1

The largest and most ambitious prevention trial conducted to date is the Diabetes Prevention Trial - type 1 (DPT-1), begun in 1994. The study was designed to determine if it is possible to prevent or delay the onset of type 1 diabetes in people who are at risk for developing the disease. The theory behind the trial was that by receiving low-doses of insulin over a sustained period, the immune system could learn to become "tolerant" to insulin and therefore leave the insulin-producing beta-islet cells alone.

After an initial screening, patients were assigned, depending upon their level of risk (based on family history and genetic profiles), to one of two trial arms:

• The insulin injection trial (completed). People who were determined to be at high risk of developing type 1 diabetes within five years were randomly assigned to either a treatment group or control (untreated) group. The treatment group received twice-daily injections of low-dose, long-acting insulin, plus a once-a-year, five-day treatment of intravenous insulin infusion. Unfortunately, this arm of the trial proved to be a bust, with 60% of patients in both the treated and untreated groups going on to develop type 1 diabetes.
  
  
• Oral antigen trial. This, the second arm of DPT-1, involved participants at intermediate risk (25-50%) of developing type 1 diabetes within five years who are randomly assigned to receive either oral insulin or a placebo (dummy pill). "This arm of the trial is based on a completely different hypothesis [than the injection arm]," says diabetes expert John Dupre, FRCP, MA, professor of medicine at the University of Western Ontario in London, Ontario. "There is a very plausible story about regulation of the immune system exerted by the intestine, and there is quite good animal data to suggest it." The trial is ongoing, with results expected to be announced in 2004.