doctor with glucose readers; type 1 misdiagnosed as type 2

Type 1 Misdiagnosed as Type 2 in 40 Percent of Adults

A new study published in Diabetologia reveals that 40 percent of people who are diagnosed with type 1 diabetes in adulthood first receive a misdiagnosis of type 2 diabetes. Having a case of type 1 misdiagnosed as type 2 may not seem significant. After all, they’re both diabetes, right? However, this can cause serious and often irreversible health conditions.

The study

The study came out of the University of Exeter and focused on 583 participants who were diagnosed with diabetes after the age of 30. Type 1 diabetes, once called juvenile diabetes, is more commonly diagnosed in children with the average age of diagnosis being 14 years old. Although it’s uncommon, adults can still be diagnosed with type 1.

Dr. Angus Jones, lead researcher from the University of Exeter Medical School, said, “Our research shows that if a person diagnosed as type 2 diabetes needs insulin treatment within three years of diabetes diagnosis, they have a high chance of missed type 1 diabetes.”

Alarmingly, the study also found that one-third of those with type 1 misdiagnosed as type 2 were still being treated for type 2 diabetes 13 years later, opening the door for long-term health consequences for these patients.


Long-term health consequences

When a person is diagnosed with type 2 diabetes, their doctor often prescribes oral medication and a lifestyle change in order to regulate their blood sugar. Someone with type 1 diabetes must take insulin through injection or a pump in order to regulate their blood sugar levels. This is because their pancreas produces little to no insulin to do this job for them.

A case of type 1 misdiagnosed as type 2 is significant because a misdiagnosis can prevent someone with type 1 from getting insulin to stabilize their blood sugar levels. This has the potential to cause complications like limb amputation, kidney failure, blindness, and cardiovascular disease.

Testing for diabetes

A contributing factor for these misdiagnoses could be that the National Institute for Health and Care Excellence (NICE) does not have strict guidelines to differentiate testing for type 1 and testing for type 2.

infographic showing the difference between type 1 and type 2 diabetes

If a doctor suspects your blood sugar is high, they may perform a number of tests, including an A1c, fasting plasma glucose test, and an oral glucose tolerance test. While these tests are reliable to test for diabetes, especially when using in conjunction with one another, these tests do not necessarily distinguish one type from another.