For most people, the onset of type 1 diabetes (T1D) seems to occur suddenly, often resulting in a trip to the emergency room with life-threatening complications. TrialNet, a worldwide leader in type 1 diabetes research, is working to change that scenario with a new type 1 diabetes staging classification system.

The new staging classification is vital to understanding how type 1 progresses, says Carla Greenbaum, MD, director of BRI’s Diabetes Research Program and chair of TrialNet. Equally important is TrialNet’s ability to diagnose the disease in its earliest stages, allowing for prompt intervention.

“Identification of the pre-symptom stages of type 1 diabetes can be compared to identification of high blood pressure as a predictor of heart attack and stroke,” notes Dr. Greenbaum. “Before treatment for high blood pressure became commonplace, we were missing a key tool to prevent heart disease. Today, people can receive intervention long before they experience symptoms or significant complications. The same is now true for type 1 diabetes.”

In the Jan. 2016 issue of Diabetes Care, the JDRF, American Diabetes Association (ADA) and Endocrine Society recommended adoption of a new type 1 diabetes staging classification. This recommendation is largely based on two decades of TrialNet research involving more than 150,000 relatives of people with type 1 diabetes. TrialNet, funded by the National Institutes of Health, is an international network of leading academic institutions, physicians, scientists and healthcare teams at the forefront of type 1 diabetes research. BRI has been involved with TrialNet since the network’s inception in 2001 and directs the TrialNet Clinical Network Hub and the TrialNet Northwest Clinical Center. 

“TrialNet’s goal is to identify the disease at its earliest stage, delay progression and ultimately prevent it. We offer screening and clinical trials for every stage of type 1 diabetes and also close monitoring for disease progression,” explains Dr. Greenbaum.

Type 1 diabetes can now be most accurately understood as a disease that progresses in three distinct stages.

Type 1 Diabetes

Stage 1 is the start of type 1 diabetes — there are no symptoms and blood sugar remains normal. Individuals test positive for two or more diabetes-related autoantibodies. The immune system has already begun attacking the insulin-producing beta cells.

In Stage 2, like stage 1, there are no symptoms and individuals have two or more diabetes-related autoantibodies. But now, blood sugar levels have become abnormal due to increasing loss of beta cells.

For both stages 1 and 2, there is nearly a 100 percent risk of developing type 1 diabetes.

Stage 3 is when individuals generally show common symptoms of type 1 diabetes, which include frequent urination, excessive thirst, weight loss and fatigue. Clinical diagnosis has typically taken place by this time and there is significant beta-cell loss.

Clinical research supports the usefulness of diagnosing type 1 diabetes early. The sooner diagnosis is made in the disease process, the earlier intervention can take place, and the more beta cells are likely to remain. More beta cells may lead to better outcomes regarding blood sugar control and reduction of long-term complications.

For people who participate in type 1 diabetes prevention research like TrialNet, the risk of diabetic ketoacidosis (a life-threatening diabetes complication) at diagnosis decreases from 30 percent to less than 4 percent. Family members of people with type 1 diabetes have a 15 times greater risk of being diagnosed than a person with no family history. Learn more about screening at and BRI’s diabetes research program.


Originally published in BRING IT ON newsletter - Spring 2016

Fighting Diseases

May 1, 2016

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