While death is inevitable, knowing when it will come isn’t necessarily, and scientists have been trying to develop a test that could reliably and easily predict how long a person will live — or, more technically, how healthy they are and therefore how vulnerable they might be to major mortality risk factors. Blood tests are the most likely avenue to such a test, since it’s easy to obtain blood samples and labs equipped to handle them are common.
The latest effort is described in a new paper published in Nature Communications, by a team led by Joris Deelen, postdoctoral researcher at the Max Planck Institute for the Biology of Aging and P. Eline Slagboom, head of molecular epidemiology at Leiden University Medical Center. The researchers report that, in a group of more than 44,000 healthy patients, their blood test was around 80% accurate in predicting mortality risk within five to 10 years.
The patients, who ranged in age from 18 to 109 years, provided blood samples and had their health events tracked for up to 16 years. The researchers analyzed a group of 226 so-called metabolites, or by-products of things that various cells and tissues in the body pour into the blood stream for circulation and removal. From this collection of markers, the team narrowed down the list to 14 that they determined could together, and along with the person’s sex, provide a pretty good picture of each person’s health risk, and, by association, their risk of dying in the next five to 10 years. They accomplished this by comparing those who died during the study to those who did not and isolating which agents in their blood differed to statistically significant amounts. The link between the final 14 factors and mortality remained strong even after the scientists accounted for potential confounding factors that also affect survival such as age, sex, and cause of death.