We've long known age is just a number, but now science has gone and proved us right. New research suggests that our biological age might not be as big of a factor in determining how long we'll live — and thanks to a team of Yale scientists, there might soon be a blood test to tell us exactly how much time we have left on earth.
The study, published on BioRxiv on July 5, was based on the idea that there are two different methods to determine age: chronological age (or number of years out of the womb) and phenotypic age (the age of the body based on a person's health as measured by specific biomarkers — or biological characteristics). According to the research, if a person's phenotypic age is higher than their regular age, they are at a greater risk of mortality than those of their "younger" counterparts. With this in mind, the team at Yale set out to develop a blood test that could determine phenotypic age based on these biomarkers.
The scientists gathered data from the U.S. National Health and Nutrition Examination Survey. Data from 10,000 people collected between 1988 to 1994 was analyzed in order to determine which biomarkers could be used to assess phenotypic age and mortality risk. After the nine most significant biomarkers were determined, another group of 11,000 participants were studied from 1999 to 2010, and the same conclusions were drawn. Some of the most important clinical factors of phenotypic age proved to be white blood cell count, glucose levels, and levels of albumin — a protein which is made by the liver. Medical history, lifestyle, and cause of death (if applicable) were also factors that were studied for the research.
"It’s picking up how old you look physiologically," Morgan Levine, a patholigist at Yale University told The Guardian. "Maybe you’re 65 years old, but physiologically you look more like a 70-year-old, so your mortality risk is more like that of a 70-year-old.”
And the researchers insist that the new test does so much more than your standard GP-administered blood tests, which adhere to strict thresholds and averages that don't accurately determine the state of an individual's health. “We want to understand the risks for the majority of the population who are middle aged, who don’t have things wrong with them, and would be missed with traditional health assessments,” Levine said.
Overall, scientists are confident that the development of the new blood test holds much promise for the future of medicine and mortality. “We showed that even among people who have no diseases, who are presumably healthy, we can still pick up differences in life expectancy. It’s capturing something pre-clinical, before any diseases present themselves,” said Levine. This means that the test will help physicians to encourage healthy lifestyle choices that could positively influence a patient's life expectancy before the onset of any serious diseases or illnesses.
“The biggest advantage of this is now being able to say someone’s at high risk, and that they should come in regularly so you can make sure they’re not developing this or that disease. It’ll show you how can you reduce their risk because you can plug all the numbers in and see how the risk drops if they bring their glucose down, for example,” Levine added. While the team at Yale hasn't yet said when the new tests will become available, we are excited about this new development for the future of healthcare.