A study has revealed that a single brain scan during middle age can indicate the speed of aging and predict the likelihood of developing diseases later on. It appears that early diagnosis of Alzheimer's disease is also possible through brain health assessment, which may aid in treatment.
Researchers from Duke University, Harvard University, and the University of Otago in New Zealand announced on April 1 (local time) in the international journal Nature Aging that "a single brain imaging scan taken during middle age can estimate how quickly one ages and track health and disease."
The researchers tracked 1,037 individuals born in Dunedin, New Zealand, between 1972 and 1973 from ages 3 to 45. They measured blood pressure, body mass index (BMI), glucose, cholesterol levels, lung and kidney function, gum health, and dental cavities. Some dropped out during the study, ultimately providing health information for 860 individuals.
The research team analyzed aging speed using software called DunedinPACNI, which stands for "Dunedin pace of aging calculated by neuroimaging." The team input 42 years of health data for 860 subjects along with their brain MRI (magnetic resonance imaging) taken at age 45 to learn the relationship between brain imaging and aging.
The analysis showed that those who age quickly exhibit diminished cognitive function because the hippocampus, which is responsible for memory, shrinks rapidly. The researchers noted that "if middle-aged aging occurs, there is a risk of developing degenerative neurological diseases in older age."
DunedinPACNI was able to estimate the speed of aging even with just the brain images, without any other information later. The researchers separately captured brain images of 624 individuals aged 52 to 89 residing in North America to measure aging speed. Those estimated to age quickly had a 60% higher likelihood of developing Alzheimer's disease. There was also a higher risk of heart attack, lung disease, and stroke. The probability of death was 40% higher than that of those who aged slowly.
The research team believes that this method can also facilitate early diagnosis of Alzheimer's disease. Alzheimer's disease is typically a degenerative neurological condition caused by an excessive build-up of abnormal proteins in the brain. Though it leads to memory loss and difficulties in daily life, it cannot be fully cured. Alzheimer's treatment starts after symptoms appear, making it more about alleviating symptoms than halting the progression.
With the aging society, the economic expense due to Alzheimer's disease is also skyrocketing. According to a paper published last year by Harvard University research team in Nature Aging, global treatment expenses for Alzheimer's disease are estimated to reach $9.12 trillion (1,239.5 trillion won) by 2050.
Ahmad R. Hariri, a professor at Duke University, expressed optimism that discovering individuals at a high risk of developing Alzheimer's disease through brain imaging could allow for appropriate treatment to prevent brain damage before symptoms appear.
References
Nature Aging (2025), DOI: https://doi.org/10.1038/s43587-025-00897-z