Understanding the Stages of Type 1 Diabetes: Insights from Dr. Matthew Corcoran
Type 1 diabetes (T1D) has long been thought of as a sudden diagnosis—one day you’re healthy, the next you’re living with a chronic condition. But medical understanding has evolved, and experts like Dr. Matthew Corcoran, endocrinologist with Shore Physicians Group, are working to help the public understand that type 1 diabetes actually progresses through distinct stages, before any symptoms appear. The concept of “stages” in type 1 diabetes comes from years of clinical research, notably from internationally recognized experts as well as organizations like the Juvenile Diabetes Research Foundation (JDRF) and the American Diabetes Association.
Dr. Corcoran recently appeared on local talk radio station WOND 92.3FM/1400AM to discuss this very topic, emphasizing how this newer framework of classification can lead to earlier detection, more effective monitoring, and possibly even future interventions to prevent full onset of the disease.
During his WOND interview, Dr. Corcoran emphasize the importance and understanding that type 1 diabetes is not simply an autoimmune disorder of children and teens. Fifty percent of those people diagnosed with type 1 diabetes are over the age of 20 years of age, and he notes that he routinely diagnosis people who are in their 50s through 70s with type 1 diabetes. Corcoran broke down the disease progression of type 1 diabetes into three defined stages:
Stage 1: Autoimmunity Begins (No Symptoms)
At this stage, an individual has two or more diabetes-related autoantibodies, but normal blood sugar levels. There are no symptoms, and the individual likely feels completely healthy. This stage is often only identified through screening—usually in people who have a family history of T1D or participate in research programs.
Dr. Corcoran explained that while this stage is “invisible,” it is crucial: “This is when the immune system has begun attacking the insulin-producing beta cells of the pancreas, but enough cells are still functioning to keep glucose levels in a healthy range.”
Patients with Stage 1 Type 1 diabetes have nearly a 100% risk of progressing to Stage 3 and the need for insulin therapy.
Stage 2: Blood Sugar Abnormalities (Still No Symptoms)
Here, autoantibodies are still present, but now glucose levels begin to rise, especially after meals. There still aren’t outward symptoms, but the body is starting to struggle with insulin production. People in stage 2 have a 75% risk of progressing to stage 3 type 1 diabetes and requiring insulin within the next 5 years, and their lifetime risk of progression is nearly 100%.
“Stage 2 is when we may start to see early signs in lab work, even if the person still feels completely normal,” noted Dr. Corcoran. This stage represents a critical window for possible intervention and monitoring. Importantly, in the past 2-3 years a landmark immunotherapy has been approved for use in those who are 8 years of age and older with stage 2 type 1 diabetes. This therapy delays the progression from stage 2 to stage 3 type 1 diabetes. In doing so, the therapy delays the need for intensive insulin therapy, as well as all of the monitoring and management that comes with the progression from stage 2 to stage 3.
Dr. Corcoran emphasizes that the glucose levels in stage 2 are consistent with what is commonly known in the community as prediabetes. In his opinion, it is critical that we evaluate these people with prediabetes and high risk for type 1 diabetes and/or other autoimmune disorders for the possibility of autoimmune related or type 1 diabetes and not simply assume that it represents a stage prior to type 2 diabetes. If we do not do this, many people in our community will begin therapy for the management of type 2 diabetes as opposed to the appropriate management of type 1 diabetes.
Stage 3: Clinical Diagnosis
Stage 3 is the traditional point of diagnosis, when symptoms appear and blood sugar levels become clinically abnormal. These symptoms typically include increased thirst, frequent urination, weight loss, and fatigue.
“This is the stage people are most familiar with,” said Dr. Corcoran, “but we now know that the disease process has been underway for many months to years before these symptoms show up.”
Recognizing that type 1 diabetes develops in stages empowers patients and families to take action earlier—sometimes even before symptoms appear. This knowledge opens the door to a proactive approach centered on doing whatever is necessary—whether that means starting medication, adopting a nutrition plan, increasing physical activity, or making broader lifestyle changes—to help delay progression to full clinical diabetes. Dr. Corcoran emphasized that with the right interventions and support, individuals at risk can often manage their condition more effectively and improve long-term outcomes.
In addition to treating patients at Shore Physicians Group, Dr. Matthew Corcoran is also the founder and president of Diabetes Training Camp (DTC), a unique South jersey based nonprofit dedicated to empowering people with diabetes to thrive through education, fitness, and community support. DTC recently hosted an educational event focused on raising awareness about the stages of type 1 diabetes, offering attendees practical guidance and clinical insight into early detection and disease progression. The event featured Dr. Corcoran, who shared the same science-based, proactive approach he discussed on WOND, highlighting how understanding the stages can lead to more personalized and effective care. The event exemplified DTC’s mission to not only educate but also motivate individuals to take control of their health and diabetes journey. DTC also just wrapped up its 1st in person camp of the season-a wellness-based camp for adults with type 1 diabetes that they host every June at Stockton University in Atlantic City.
The understanding of type 1 diabetes is evolving, and thanks to dedicated professionals like Dr. Matthew Corcoran, patients and families have access to the latest science and tools. Whether through educational outreach on platforms like WOND or programs like Diabetes Training Camp, the message is clear: knowledge is power.
If you or a loved one has a family history of type 1 diabetes, speak with your healthcare provider about screening options. Early knowledge of your risk could make all the difference.
Endocrinologist Dr. Matthew Corcoran treats patients Shore Physicians Group’s Endocrinology office located at 18 West New York Ave in Somers Point, NJ. To schedule an appointment with Dr. Corcoran, call 609.365.5300.
