A new global study led by researchers from University College London (UCL) has found that people with dementia are often diagnosed years after their first symptoms appear.
On average, the delay is about 3.5 years, and for those with early-onset dementia, it can take even longer—around 4.1 years. These long waits can prevent people from getting the help and support they need in time.
The study, published in the International Journal of Geriatric Psychiatry, is the first of its kind to systematically review and analyze data from across the world about how long it takes to diagnose dementia.
The researchers looked at 13 different studies conducted in Europe, the U.S., Australia, and China. Together, these studies included data from over 30,000 people.
The researchers focused on the time between when someone or their family first noticed symptoms—like memory problems or confusion—and when they were officially diagnosed by a doctor. In many cases, this gap stretched over several years.
Dr. Vasiliki Orgeta, the lead author from UCL’s Division of Psychiatry, explained that diagnosing dementia early is very important because it gives people more time to access treatment and live independently before the condition worsens.
However, she said that many people are never diagnosed at all. In high-income countries, only about half to two-thirds of cases are ever officially diagnosed, and the numbers are even lower in other parts of the world.
The study found that some people are more likely to face delays than others. People with early-onset dementia—meaning they show symptoms before age 65—often wait longer for a diagnosis.
The same is true for those with a type of dementia called frontotemporal dementia. Limited data also suggests that racial differences may play a role, as one study found that Black patients tended to be diagnosed later than others.
Dr. Orgeta stressed the need for better healthcare systems and public education to address these delays. She called for a clear strategy to improve diagnosis times, created with input from people living with dementia and their families.
Dr. Phuong Leung, also from UCL, noted that many early signs of dementia are mistaken for normal aging. Fear, stigma, and a lack of understanding may stop people from seeing a doctor. Other barriers include limited access to specialists, long waiting times at memory clinics, and not having culturally appropriate tools for assessment.
Professor Rafael Del-Pino-Casado from the University of Jaén in Spain added that people from different cultural or language backgrounds may find it harder to access care and get diagnosed early.
To fix these problems, the researchers recommend several changes. Public awareness campaigns can help people recognize symptoms sooner and feel more comfortable seeking help. Doctors and healthcare workers need better training to spot early signs and refer patients quickly.
More support services and faster access to testing are also needed to make sure people with dementia and their families get the care they deserve.
This study is a strong reminder that early diagnosis of dementia is possible—but only if health systems, doctors, and communities work together to make it happen.
If you care about dementia, please read studies about low choline intake linked to higher dementia risk, and how eating nuts can affect your cognitive ability.
For more information about brain health, please see recent studies that blueberry supplements may prevent cognitive decline, and results showing higher magnesium intake could help benefit brain health.
The study is published in the International Journal of Geriatric Psychiatry.
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