Professor Richie Poulton
The Study has tracked more than a thousand people born in Dunedin in 1972-73 from birth to the present. A large number of health measures—including blood pressure, white blood cell count, liver and kidney function— have been taken regularly along with interviews and other assessments.
In a paper appearing the week of July 6 in the Proceedings of the National Academy of Sciences, a team from the US, UK, Israel and New Zealand unveil a panel of 18 biomarkers that can be combined to determine whether people are aging faster or slower than their peers.
Dunedin Study Director Professor Richie Poulton says when the 18 measures were assessed together in Study members at age 38, they were able to set ‘biological ages’ for each person. In contrast to their chronological ages, these ranged from under 30 to nearly 60 years.
The researchers then went back to look at the individuals’ same measures at age 26 and 32.
After drawing a slope for each variable, the team added the18 slopes for each member to determine that individual’s hidden pace of aging while they were still young on the outside.
Professor Poulton says most study members were found to be clustered around one biological year per chronological year, but others were found to be aging as fast as three biological years per actual year. Many were aging at zero years per year; they were staying younger than their age.
“As we expected, those who were biologically older at age 38 also appeared to have been aging at a faster pace. A biological age of 40, for example, meant that person was aging at a rate of 1.2 years per year over the 12 years the study examined,” Professor Poulton says.
They found that individuals who were aging more rapidly were less physically able, showed cognitive decline and brain aging, reported worse health, and looked older. The latter was based on Duke University students’ judgement of relative age based on study members’ facial photographs.
Professor Poulton says that being able to detect accelerated aging at an early stage paves the way for applying therapies that slow aging and lessen age-related ailments.
“Currently, we are largely stuck in an ‘ambulance at the bottom of the cliff’ situation. And by 2050, the world population aged 80 years and over will approach 400 million people, so we are facing an enormous global burden of disease and disability unless we can extend healthy lifespans.”
First author of the paper, Dan Belsky, an assistant research professor at Duke University’s Center for Aging, says the methods outlined in the article are merely a proof of concept to show that it is possible to see an aging trajectory by combining multiple measures.
“The time is right for this kind of multi-factorial way of measuring the aging process, but the measures and methods will have to be refined to be “better, faster and cheaper,” Dr Belsky says.
The ultimate goal, of course, is to be able to intervene in the aging process itself, rather than addressing killers like heart disease or cancer in isolation, he says.
“Aging itself has to be the target to prevent multiple diseases simultaneously, otherwise it’s a game of whack-a-mole.”
This research was supported by the New Zealand Health Research Council, the US National Institute on Aging, the UK Medical Research Council, the Jacobs Foundation, and the Yad Hanadiv Rothschild Foundation.
For more information, contact:
Professor Richie Poulton
Director, Dunedin Multidisciplinary Health and Development Research Unit
Department of Psychology
University of Otago
Tel 64 3 479 8507