Dementia Often Misdiagnosed As Normal Aging For 3.5 Years, New Study Finds

August 13, 2025 - Korin Miller | Women's Health Magazine

Originally published on Women's Health Magazine on August 13, 2025.

Receiving a diagnosis like dementia doesn’t happen overnight, but the amount of time it takes to learn what’s really going on has always been a little hazy. Now, new research has pinpointed how long it takes on average to get a dementia diagnosis—and there’s a greater span between initial symptoms and diagnosis than most people realize.

The scientific review, which was published in the International Journal of Geriatric Psychiatry, is the first to break down evidence from around the world on the general timeline for diagnosing dementia. Here’s what the study found, plus what neurologists want you to keep in mind.

What did the study find?

For the study, researchers analyzed data from 13 studies on dementia that were conducted across the U.S., Europe, Australia, and China. Overall, the studies featured 30,257 participants.

After crunching the numbers, the researchers discovered that it usually takes 3.5 years from the first symptoms someone shows of dementia to an actual diagnosis. In people who have early-onset dementia—which is dementia diagnosed before the age of 65—that timeline stretches to 4.1 years.

People who had frontotemporal dementia, which leads to changes in personality, behavior, and language, and is more common in younger people, also faced a longer time to diagnosis.

hy can signs of dementia be hard to miss early on?

Some memory loss is common as you get older, and dementia symptoms are progressive—meaning, they don’t usually come on hard and fast, explains Amit Sachdev, MD, MS, the medical director in the Department of Neurology at Michigan State University. As a result, it can take a while to piece everything together.

Memory loss in younger people is tough to diagnose for the reasons we just listed, along with the fact that dementia is rare in younger people, says Clifford Segil, DO, a neurologist at Providence Saint John’s Health Center in Santa Monica, CA. “People with memory loss who are not old usually don’t think about seeing a neurologist,” he says. “I suspect the delay in diagnosing young onset dementia is directly related to there being a shortage of neurologists and young people getting their memory loss evaluated by their primary care physicians rather than a neurologist.”

How to tell the difference between dementia and normal aging

Frontal temporal dementia, which is more common in younger patients, can lead to changes in personality, mood, and behavior, which can be tricky to pin to dementia, Segil says. “But if you have acute onset cognitive changes as a young adult with new changes in personality, mood, and behavior or with changes in your ability to talk or understand, go find a neurologist and ask them to evaluate you for young onset dementia,” he says.

For older adults, there can be a range of symptoms that people might have. “Early signs can include being forgetful to the extent that is it impacting daily function, changes in mood and demeanor, feeling lost in familiar places, missing bills, or having trouble managing finances,” Sachdev says.

Ultimately, if you or a loved one is having trouble with memory and you don’t have answers, Segil says it’s crucial to see a neurologist for an evaluation. While it may be due to dementia, these symptoms could also be from something else entirely different—and you won't know until you get them checked out.

Meet the expert: Clifford Segil, DO, is a neurologist at Providence Saint John’s Health Center in Santa Monica, CA; Amit Sachdev, MD, is the medical director in the Department of Neurology at Michigan State University.