Natural History Study

Status: Recruiting

Eligibility Criteria

To be screened, you must fulfill at least one of the two conditions below:

• 1 to 45 years of age and have a brother, sister, child, or parent with type 1 diabetes
• 1 to 20 years of age and have a cousin, aunt, uncle, niece, nephew, half sibling, or grandparent with type 1 diabetes

About this Study

The Natural History Study of the Development of Type 1 Diabetes will study people at increased risk for type 1 diabetes to learn more about how type 1 diabetes occurs.

TrialNet is screening close blood relatives of people with type 1 diabetes because relatives of people with type 1 diabetes have a 10 to 15 times greater risk for developing the disease than people with no family history.

Phase 1: Screening

The screening phase of the Natural History Study identifies people at increased risk for developing type 1 diabetes.

People who qualify and choose to participate in the Natural History Study may also be offered an opportunity to enter a diabetes prevention study in the future.

What is the purpose of these screening tests?

The first screening test looks for autoantibodies associated with type 1 diabetes in your blood. Autoantibodies are proteins made by the immune system.

Autoantibodies are a sign that your immune system may be attacking the insulin- producing cells in your pancreas. Having these autoantibodies places you at greater risk for developing diabetes.

About 3 to 4 percent of family members of people with type 1 diabetes will have autoantibodies in their blood.

To do this screening test, a small sample of blood is drawn from your arm at a TrialNet clinic or you can ask us to send you a test kit that you can take to a local lab or your own doctor to have your blood drawn. Then the blood sample is sent to the TrialNet central laboratory for analysis.

In 4 to 6 weeks, you will learn your test results. We will send you a letter if the test shows that you do not have autoantibodies (negative result).

Testing negative for autoantibodies doesn't mean you will never get diabetes. It does mean that your chances for developing type 1 diabetes are lower than if you had autoantibodies. If you are under 18 years of age, you can have the blood test for autoantibodies every year.

If you have autoantibodies in your blood, (positive result) we will call you to discuss your results.

Testing positive doesn't mean that you will get type 1 diabetes. It means that have a greater chance of developing diabetes than if you tested negative. We will ask you to come to the clinic for more blood tests to confirm the positive result. If the repeat tests indicate the presence of at least one autoantibody associated with type 1 diabetes, we will invite you to take additional tests to better determine your risk for developing diabetes. The new tests are conducted in Phase 2 of the Natural History Study.

Phase 2: Baseline Risk Assessment

The Phase 2 blood tests are used to estimate your chances of developing type 1 diabetes over the next 5 years. Your risk level may be:

• Less than 25 percent chance
• 25 to 50 percent chance
• Greater than 50 percent chance

After the Phase 2 testing, we will ask if you would like to take part in Phase 3. All participants in Phase 2 and 3 will be closely monitored for early detection of type 1 diabetes.

Phase 3: Follow-Up Risk Assessment

People who participate in Phase 3 will have additional blood tests to see if their immune function changes and whether or not they are developing diabetes. They may also be offered enrollment in a future diabetes prevention study.

People who develop diabetes while participating in the Natural History Study may be able to participate in a TrialNet study to preserve insulin-producing cells.

Participation

Before you have the autoantibody test, you must give permission to have the test performed by signing an Informed Consent form. Parents must give permission for children under 18 years of age to be tested. Please read the Informed Consent form carefully. A TrialNet health professional will talk to you about the test and the Informed Consent form. Please discuss any questions or concerns with this TrialNet staff person.

If you choose to participate in the second or third phases of the study, we will ask you to sign a separate Informed Consent form for each phase.

If you participate in phase 1, you do not have to participate in any other phase of the study. For more information on the 3 phases of this study, please refer to the study fact sheets

To see if you might be eligible for this study and for a referral to a TrialNet site:

• Complete the online screening,
• Call toll free anytime 1 - 800 - HALT - DM1 (1-800-425-8361)
• Contact a participating center.

If you call us, you will receive:

• A phone evaluation to find out if you might be eligible for any current TrialNet studies
• A referral to the closest clinical site in your area
• An information packet for the type of research that is of interest to you

If you wish to be tested for diabetes risk, but do not live near a TrialNet site, we will refer you to a TrialNet staff person at a Clinical Center who will explain the screening process and provide you with a test kit to have your blood test drawn by your own doctor or local laboratory.

Information will be kept confidential.