My family recently participated in a study trying to link first degree relatives of type 1 diabetics and autoantibodies. Everyone’s test came back normal except mine. I am 32 years old and I was positive for the GAD-65. My youngest son has type 1 diabetes, diagnosed three years ago. I do have a family history of type 2 (mother and maternal grandparents), but no other type 1 history, to my knowledge. I am grateful that we are very familiar with this and we know the symptoms. What is the chance that I will develop type 1 based on this positive result and also a son with the disease? Is there anything that I can do to prevent it, like diet or exercise?

Prevention of type 1 diabetes is less clear than type 2 diabetes. The study known as TrialNet has been looking at this in first-degree family members who have type 1 diabetes. Generally, when they do the screen, and one of the antibodies are positive, you are invited to participate in a staging phase that uses multiple tests to diagnose your risk for determining type 1 diabetes. Because you are 32, your risk, over time, would be less than if you were a child. However, just having the antibody does not mean you will get type 1 diabetes. The staging takes into account how much insulin you put out to a challenge of intravenous glucose, an oral glucose challenge test, your other antibody levels in your blood, and other risk factors known to impact the development of diabetes. If you only have the antibody and nothing else, your absolute risk is still probably low. However, your risk compared to the rest of the population that does not have the antibody is relatively high (called the relative risk). Your absolute risk is still probably low, but a more precise determination can be made if you have the staging done as part of the study. If you are interested in the TrialNet study, you can contact the national recruiting number at 1-800-425-8361.

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