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Younger Age of Onset Diabetes Increases the Risk for Dementia Later in Life

New research finds that people with prediabetes who went on to develop diabetes before age 60 are at a higher risk for dementia. The findings highlight the importance of preventing disease progression in those with prediabetes to stave off future complications like dementia.

People who develop diabetes before age 60 may be at greater risk for dementia later in life, finds new research

Of significance was the age of onset diabetes; study participants diagnosed with type 2 diabetes before age 60 were nearly three times more likely to develop dementia compared to those who were older when diagnosed with diabetes. 

“People who are diagnosed with diabetes at younger ages often have much more severe diabetes and will be exposed to high blood glucose for a long period of time over their lifespan,” said Elizabeth Selvin, study author and professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health. “This can contribute to a much greater risk of complications as compared to persons who are diagnosed with diabetes later in life.”

Some of these long-term complications include heart and blood vessel diseases, kidney problems, and the focus of Selvin’s research, cognitive conditions like dementia. A potential key to reducing the dementia burden, Selvin said, is preventing the progression of prediabetes – especially in younger people.

Does prediabetes affect dementia risk?

Previous studies have identified a link between prediabetes and dementia, but it wasn’t clear whether prediabetes alone was a risk factor for it. Based on Selvin’s research, it now appears the association between the two has to do with whether a person goes on to develop diabetes.

“Prediabetes matters for dementia mostly because these patients are at increased risk for diabetes,” said Selvin.

Up to 70% of people with prediabetes will go on to develop diabetes at some point in their life, and as other research points out, having type 2 diabetes increases the risk of dementia. Even though diabetes is a metabolic condition, there is a physiological explanation for how exactly it impacts cognitive function.

“A buildup of proteins may cause the loss of brain cells, which in turn can lead to dementia,” explained Selvin. “Insulin resistance and high blood sugar, which occur in diabetes, are thought to contribute to the buildup of these proteins.”

Because prolonged levels of high blood sugar (hyperglycemia) play a part in cognitive decline, improving glucose control may help stave off dementia in people with diabetes. But before it gets to that point, Selvin said prevention is key.

Living with prediabetes: how to prevent disease progression

Because of the substantially higher risk for dementia in those with early-onset diabetes, researchers like Selvin emphasized the importance of preventing disease progression in people living with prediabetes.
The good news about prediabetes is it’s reversible and does not always advance to diabetes. With some relatively simple lifestyle changes, people have the power to prevent their prediabetes from evolving into type 2 diabetes, which is more difficult to manage.

“Even modest weight loss (5-10%) can have a major impact to help prevent diabetes,” said Selvin. “The results of our study suggest that if we can prevent people with prediabetes from progressing to diabetes, we could help prevent dementia later in life.”

If you’re a person with prediabetes, other lifestyle changes you can make on your own to prevent disease progression include: 

  • Increasing physical activity 

  • Consuming fewer calories 

  • Eating a healthy diet rich in fruit and vegetables

  • Weight loss and preventing additional weight gain

To learn more about prediabetes and prevention, check out some of our articles here: