Blood test for the biological age of the organs

Blood test for the biological age of the organs

Our organs age at different rates. © Ekaterina Chizhevskaya/ iStock

Our biological ages do not always match our chronological ones. Using machine learning, a research team has now analyzed thousands of proteins in human blood and found markers for the biological age of our individual organs. Accordingly, our organs age at different rates, and prematurely aged organs are associated with an increased risk of illness and death. Based on their findings, the researchers have developed a blood test that could make it possible to discover and treat health risk factors earlier in the future.

As we age, the structure of our tissues gradually changes. The functionality of our organs decreases and the risk of chronic diseases increases. Depending on our disposition and our lifestyle, our biological age does not necessarily correspond to the age we see on the calendar. Animal studies have even shown that the biological age of individual organs can vary significantly. However, it was still unclear whether this also applies to humans.

Machine learning reveals new biomarkers

A team led by Hamilton Se-Hwee Oh from Stanford University in California has now shown that our organs also age at different rates and therefore contribute to our risk of illness and death to different extents. “Numerous studies have identified individual values ​​that represent a person’s biological age, that is, the age that can be derived from a series of biomarkers – as opposed to the calendar age, which is based on the actual years that have passed since their birth. “says Oh’s colleague Tony Wyss-Coray. “We went one step further and developed a method to estimate the biological age of individual organs.”

To do this, the team used blood values ​​and health data from a total of 5,676 people from five large cohort studies in the USA. Using machine learning, the researchers analyzed which proteins in the blood specifically provided information about the condition of individual organs or tissues. In fact, they identified 858 blood markers whose concentrations provided information about the biological age of the heart, fatty tissue, lungs, immune system, kidneys, liver, muscles, pancreas, brain, blood vessels and intestines. From the average levels of these blood markers in healthy people, Oh and his team determined age-appropriate normal values ​​for each organ. Deviations from these values ​​mean that the respective organ is older or younger in terms of its functionality than the calendar age suggests.

Increased risk of illness and death

“When we compared the biological age of each of these organs in a large group of people without obvious serious illnesses, we found that 18.4 percent of people over 50 had at least one organ aging significantly faster than average,” said Wyss -Coray. “And we found that these people had an increased risk of developing disease in the organ in question within 15 years.” Premature aging usually only affected one of the eleven organs and tissues included. However, in 1.7 percent of the people examined, two or more organs were biologically significantly older than their calendar age would suggest. “These people had a 6.5 times higher risk of mortality than someone without a significantly aged organ,” reports Wyss-Coray.

According to the researchers, determining the biological age of the individual organs can also help identify disease risks at an early stage. For example, apparently healthy people whose hearts were four years older than the calendar age according to the blood test had a 2.5 times higher risk of heart failure than people with normally aging hearts. The risk of high blood pressure and diabetes was increased in people with “older” kidneys. When it comes to the brain, the blood test was able to predict the risk of Alzheimer’s disease as well as the best clinical biomarkers currently in use.

Approaches for early detection and therapy

“If we can reproduce this finding in 50,000 or 100,000 people, it means that by monitoring the health of individual organs in apparently healthy people, we might be able to find organs that are undergoing accelerated aging in people’s bodies,” says Wyss-Coras. “Then we could treat people before they get sick.” The identified blood markers could also help to find target structures for new drugs that could possibly return the patient to a younger, healthier state.

Source: Hamilton Se-Hwee Oh (Stanford University, California, USA), Nature, doi: 10.1038/s41586-023-06802-1

Recent Articles

Related Stories

Stay on op - Ge the daily news in your inbox