Getting older is inevitable, but illness doesn’t have to be. Scientists have developed a groundbreaking tool that can measure how fast a person is aging and predict their future risk of chronic diseases like dementia using a single brain MRI scan. This early warning system could empower individuals to make lifestyle changes while they are still young and healthy enough to potentially slow or even prevent health problems down the line.
The technology, known as DunedinPACE, is the brainchild of scientists at Duke University, Harvard University, and New Zealand’s University of Otago. It leverages data from the Dunedin Study—a decades-long health project tracking over 1,000 New Zealanders born in the early 1970s. Since birth, participants have been regularly monitored for various health metrics, including blood pressure, cholesterol, lung, and kidney function, to map how their bodies have changed over time.
Revolutionizing Aging Measurement
From this extensive dataset, researchers calculated the biological aging rate of each participant—not based on their chronological age but on the physical wear and tear their bodies had endured. The team then trained the tool to predict these biological ages using just a single MRI scan of the brain taken when participants were 45 years old.
Subsequently, the tool was tested on brain scans from individuals across the US, UK, Canada, and Latin America. Consistently, it was found that people with higher aging scores performed worse on cognitive tests and showed faster shrinkage in the hippocampus, the brain region crucial for memory and learning. In one analysis, those deemed to be aging fastest faced a 60% higher risk of developing dementia compared to those with lower scores, and they began to experience memory and thinking problems sooner.
“Our jaws just dropped to the floor,” remarked Ahmad Hariri, a Duke professor of psychology and neuroscience. “It’s helping us predict diagnosis of dementia among people who are much older.”
Beyond Brain Health
Brain decline wasn’t the only red flag the tool picked up. Individuals with higher DunedinPACE scores were also more likely to suffer from age-related frailty, heart attacks, strokes, lung disease, and other chronic illnesses. Even more strikingly, they were 40% more likely to die within the next several years than their slower-aging peers.
Notably, the tool’s accuracy held up across various demographics, including race, income, and geographic location. “It seems to be capturing something that is reflected in all brains,” Hariri added.
Implications for an Aging Population
The introduction of this tool comes as the global population is aging rapidly. By 2050, nearly a quarter of the global population will be over 65—twice as many seniors as today, according to the World Health Organization. A longer life, however, often comes with the risk of chronic age-related diseases, including dementia.
Studies predict that 152.8 million people worldwide will be living with dementia in 25 years, up from 57.4 million cases in 2019. Despite this sharp rise, effective treatments for Alzheimer’s and other dementias remain elusive. Most drugs on the market manage symptoms but fail to stop or reverse the disease.
“Drugs can’t resurrect a dying brain,” Hariri explained, suggesting that existing treatments often start too late.
Future Directions and Challenges
The new tool could change the landscape by identifying individuals at risk of Alzheimer’s earlier, allowing for interventions before extensive brain damage occurs. Beyond predicting dementia risk, the tool may help scientists understand why individuals with certain risk factors—such as poor sleep or mental health issues—age differently, according to Ethan Whitman, the study’s first author and a clinical psychology PhD candidate at Duke.
However, Whitman noted that more work is needed to turn DunedinPACE into a tool that everyday healthcare providers can use. In the meantime, the team hopes the tool will aid researchers with access to brain MRI data in measuring aging in ways that algorithms based on other biomarkers, such as blood tests, cannot.
“We really think of it as hopefully being a key new tool in forecasting and predicting risk for diseases, especially Alzheimer’s and related dementias,” Hariri concluded.