Skip to Content

Blood Biomarker Is Linked with Death

Those with higher levels of a particular molecule were found to be more likely to die of heart disease or cancer in the next dozen years.
August 30, 2011

Older people who had higher than normal levels of a molecule that helps regulate inflammation in their blood were more likely to die within the next 12 years, according to a study of nearly 2,000 people in Sweden.

It’s not yet clear whether measuring this chemical, cathepsin S, could help doctors predict risk of death or disease in individuals. But the findings may renew interest in cathepsin S as a drug target. A number of drugs that inhibit the normal functioning of the molecule are already in development for autoimmune diseases, such as rheumatoid arthritis, and chronic pain.

The researchers studied two different groups of Swedes, each with an average age of about 70. Individuals were followed for eight to 12 years, during which nearly a quarter died. After controlling for other factors, such as age, weight, blood pressure, medications, and history of disease, cathepsin S levels were still linked to a greater risk of death.

In one of the two groups, those with the highest levels of the molecule had double the risk of dying during this time period than those with the lowest levels. In the second group, those with high levels of cathepsin S were more likely to die of two particular maladies: heart disease and cancer. The research was published today in the Journal of the American Medical Association.

“It predicts two of the most common causes of death, which is unusual,” says Johan Ärnlöv, a physician and scientist at Uppsala University, who led the study.

The findings follow research in animals suggesting that the molecule plays a role in both the generation of tumors and the buildup of arterial plaque, a sign of heart disease. In addition, a handful of small studies in humans found that those who were obese or had diabetes had higher levels of the molecule. “It has complex roles in the body,” says Ärnlöv. “It seems to be involved in a lot of diseases and with pain or chronic inflammation.”

That doesn’t necessarily mean that cathepsin S will help physicians predict the risk of cardiovascular disease or cancer better than existing tools can. The link to heart disease is modest, Thomas Wang, associate professor of medicine at Harvard Medical School, less than that for blood pressure or cholesterol levels. Researchers still need to determine whether the molecule is tied specifically to these diseases, or is simply a general sign of physiological aging or poor health, he says. Wang was not involved in the research.

“There are lots of things we can measure that are associated with future risk of death, but they are not useful for doctors to measure in the office,” because it remains unclear how these markers can help with treatment, says Wang. If researchers develop successful cathepsin inhibitor drugs, measuring these levels might predict who is most likely to respond.

Keep Reading

Most Popular

still from Embodied Intelligence video
still from Embodied Intelligence video

These weird virtual creatures evolve their bodies to solve problems

They show how intelligence and body plans are closely linked—and could unlock AI for robots.

conceptual illustration showing various women's faces being scanned
conceptual illustration showing various women's faces being scanned

A horrifying new AI app swaps women into porn videos with a click

Deepfake researchers have long feared the day this would arrive.

protein structures
protein structures

DeepMind says it will release the structure of every protein known to science

The company has already used its protein-folding AI, AlphaFold, to generate structures for the human proteome, as well as yeast, fruit flies, mice, and more.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.