As part of an international team studying the results of long-term health, researchers at Hebrew University have come up with biomarkers that can measure people at a younger age.
According to the researchers from Israel, the US, the UK and New Zealand, individuals could find themselves with a “biological age” that is twice as high as their actual age.
The research, said study co-author Dr. Salomon Israel of the Hebrew University’s Department of Psychology, shows that “age-related decline is already happening in young adults who are decades away from developing age-related diseases, and that we can measure it.”
Such “accelerated” aging in young adults, he added, can “predict the symptoms of advanced aging that we see in older adults, deficits in cognitive and physical functioning, feelings of ill health, and even an older appearance.”
Most studies of aging have, until now, concentrated not on younger people, but on the elderly, with researchers attempting to determine the factors that enable individuals to “age gracefully,” in relatively good mental and physical health, as compared to others whose health declines more rapidly.
“The ability to measure how quickly a young person is aging may in the future enable us to engage in interventions that slow aging or target specific diseases,” said Israel.
The research was published last week in a paper appearing in the Proceedings of the National Academy of Sciences, based on findings from the Dunedin Study, a long-term health study in New Zealand that seeks clues to the aging process. The study tracks more than 1,000 people born in 1972-1973 from birth to the present, using health measures such as blood pressure and liver function, as well as through interviews.
As part of their regular reassessment of the population sample in 2011, the team measured kidney and liver functions, and metabolic and immune systems. They also measured HDL cholesterol, cardio-respiratory fitness, lung function and the length of the telomeres — protective caps at the end of chromosomes that have been found to shorten with age. The study also measured dental health and the condition of the tiny blood vessels at the back of the eyes, a proxy for the brain’s blood vessels.
Overall, 18 biomarkers were studied by the team, who compared them at different points in the lives of the study’s participants — at ages 26, 32 and 38. Using the information, they were able to determine an individual’s pace of aging.
While most participants aged biologically as they did chronologically — an individual whose age was 35 based on their birth certificate showed biological markers of a similar age — some aged more rapidly than their chronological age, while others did not appear to be aging at all.
Study members whose biological markers were “older” scored worse on tests typically given to people over 60, including balance and coordination tests and solving unfamiliar problems. The biologically older individuals also reported having more difficulties with physical functioning than their peers, such as walking up stairs.
As an added measure, the researchers asked Duke University undergraduate students to assess facial photos of the study participants taken at age 38 and rate how young or old they appeared. Again, the participants who were biologically older internally also appeared older physically to the college students.
The current study was one of the first aging studies done involving participants who were not elderly, and its purpose was to show how decline begins far earlier than shown in previous studies. It did not attempt to determine the specific reasons for differences in the biomarkers among participants.
“We set out to measure aging in these relatively young people,” said Dan Belsky, an assistant professor of geriatrics in Duke University’s Center for Aging and the study’s first author. “Most studies of aging look at seniors, but if we want to be able to prevent age-related disease, we’re going to have to start studying aging in young people.”