SAN DIEGO — You’re only as old as you feel, according to researchers from the University of California-San Diego. After analyzing a group of over 1,800 older women, scientists report accelerated bodily aging (epigenetic age acceleration) appears to have a connection to a lower chance of both living to the age of 90 and retaining physical mobility and mental function.
Overall, study authors conclude that epigenetic age acceleration may soon become a viable biomarker for healthy longevity, used to help estimate both functional and cognitive aging.
“Older people know well that age is just a number that may not be indicative of their health status. What if we had a way to measure how fast we were aging that could predict our odds of living a long and healthy life? In aging research, we call this an individual’s healthspan,” says principal investigator Andrea LaCroix, Ph.D., M.P.H., Distinguished Professor at the Herbert Wertheim School of Public Health and Human Longevity Science, in a university release.
Chronological age is just a number
When most people think about their age, they’re focusing on their chronological age based on their birthday. Epigenetic age, on the other hand, measures the biological age of a person’s cells, tissues, and organ systems. If an individual’s epigenetic age is older than their chronological age, scientists call it epigenetic age acceleration.
Epigenetic age acceleration displays a link to higher risk levels for cancer, as well as greater odds of developing cardiovascular disease, Parkinson’s disease, and other ailments.
According to four different epigenetic “clocks” measuring biological aging, roughly every five to eight years of epigenetic age acceleration lowers the chances of living to 90 while retaining good mobility and cognitive function by 20 to 32 percent.
“Healthspan is important because the number of individuals who will live to be 90 years and older will quadruple from 1.9 million in 2016 to 7.6 million in 2050 in the United States alone,” Dr. LaCroix adds.
Epigenetic age acceleration increases the risk of death
To reach these findings, study authors analyzed data encompassing the physical and cognitive statuses of 1,813 women who participated in the Women’s Health Initiative. The long-term national health study, funded by the National Heart, Lung, and Blood Institute, began in 1993. The median age of death among initiative participants was 90 years-old.
A total of 464 women lived to 90 with their mobility and cognitive functioning intact. Another 420 lived to 90 but saw their mobility and cognitive functioning decline, and 929 women passed away before turning 90.
Participants were between 70 and 72 years-old at baseline before researchers started tracking them up until their 90th birthday or death. Importantly, study authors considered the association between epigenetic age acceleration and healthy longevity to be independent of other characteristics common among women who live to be 90 and still have good mobility and memory. These factors include being white, having no or few chronic health conditions, attaining a high level of education, not smoking, and walking multiple times weekly.
“Prior studies have shown that epigenetic age acceleration is associated with increased risk of death, and a few studies observed that slower age acceleration occurs among long-lived individuals. But this is the first study to prospectively examine the relationship between slower age acceleration and living to age 90 with preserved mobility and memory,” explains first study author Purva Jain, Ph.D., who completed this work as part of her doctoral dissertation at UC San Diego.
“Furthermore, our study suggests we can use epigenetic age acceleration to estimate the risk of an individual not attaining healthy longevity, which could lead to future public health interventions to counteract poor health outcomes among older populations,” she concludes.
The study is published in JAMA Network Open.