Key points:
- In a new study, researchers identified key pathways and compounds that are associated with both healthy and rapid aging.
- The team found key differences in the expression of metabolites—called the Health Aging Metabolic (HAM) Index—that could be used to both distinguish agers and predict walking ability.
- Researchers hope to use their results to develop a blood test that can estimate biological age.
Researchers have uncovered key pathways and compounds that are associated with both healthy and rapid aging. Their study, published in Aging Cell, allows them to predict a person’s biological age and begin to understand why people age differently.
The research team classified 196 older adults as healthy or rapid agers based on how easily they completed simple walking challenges. The healthy ager group consisted of adults who were 75 years or older that could ascend a flight of stairs or walk for 15 minutes without resting. The rapid agers, who were 65 to 75 years old, had to rest during the walking challenges.
As the rapid agers were chronologically younger than the healthy agers, the researchers could easily investigate markers of biological—not chronological—aging. To define a molecular fingerprint of biological aging, the team performed metabolomics with blood samples from the two groups. They found significant differences in the metabolomes of healthy agers compared to rapid agers, indicating that metabolites in blood could reflect biological age.
From their analysis, the researchers identified 25 metabolites that they called the Health Aging Metabolic (HAM) Index, which was better than traditional metrics at distinguishing healthy and rapid agers. In a separate cohort of older adults, their HAM index correctly predicted whether individuals could walk outside for 10 minutes without stopping with an accuracy of about 68%. The team also employed an artificial intelligence model to predict the three main metabolites that would promote healthy aging or drive rapid aging.
In the future, researchers hope to examine how the metabolome of younger people shifts over time. This knowledge could contribute to blood tests that estimate biological age and interventions that could slow the aging process.
“While it’s great that we can predict biological aging in older adults, what would be even more exciting is a blood test,” said senior author Aditi Gurkar, professor at University of Pittsburgh. “For example, we can tell someone who’s 35 that they have a biological age more like a 45-year-old. That person could then think about changing aspects of their lifestyle early to hopefully reverse their biological age.”