American and French researchers have developed a blood based epigenetic ‘clock’ that can estimate how well someone is aging, reflecting both physical and mental factors.
“In 2015, the World Health Organization introduced the concept of intrinsic capacity, defined as the sum of all physical and mental capacities that an individual can draw on at any point in their life. This concept promotes healthy aging by shifting the healthcare focus from treating acute illnesses toward measuring and preserving functional ability,” explains David Furman, a group leader at the Buck Institute for Research on Aging, and colleagues in Nature Aging.
Intrinsic capacity varies between individuals but in general peaks in early adulthood and starts to drop after midlife. However, it can be improved through lifestyle changes at any age. It includes measures such as cognition tests, physical locomotion tests, vision, and hearing, as well as vitality measures such as handgrip strength and nutritional assessment.
In this study, Furman and colleagues have linked a person’s intrinsic capacity score to DNA methylation as measured from a blood sample. They created a panel of 91 methylation sites on the DNA and created an epigenetic predictor of intrinsic capacity.
They created the clock using data from the INSPIRE-T cohort based in Toulouse, France, which includes 1,014 individuals aged 20–102 years. The team then used the trained model on data collected from the Framingham Heart Study to assess the validity of the clock.
They found the intrinsic capacity clock performed better than earlier epigenetic clock models and results correlated with changes in immune and inflammatory biomarkers, functional and clinical measures, health risk factors and lifestyle choices, as measured by the non-epigenetic intrinsic capacity calculation.
The researchers now want to develop their test further so that epigenetic intrinsic capacity can be measured from a dried blood spot, which would make testing easier and less invasive.
“If we can offer a scalable, affordable molecular level tool to assess functional decline, the intrinsic capacity clock could help clinicians, researchers, and policymakers better identify at-risk individuals and tailor interventions that promote a longer healthier life,” said Furman in a press statement.
