A new blood test that can identify the progression of osteoarthritis in the knee is more accurate than current methods, researchers report.
It could provide an important tool to advance research and speed the discovery of new therapies.
The test relies on a biomarker and fills an important void in medical research for a common disease that currently lacks effective treatments. Without a good way to identify and accurately predict the risk of
osteoarthritis progression, researchers have been largely unable to include the right patients in clinical trials to test whether a kind of therapy is beneficial.
“Therapies are lacking, but it’s difficult to develop and test new therapies because we don’t have a good way to determine the right patients for the therapy,” says Virginia Byers Kraus, a professor in the medicine, pathology, and orthopedic surgery departments at Duke University School of Medicine and senior author of the study in the journal
Science Advances.
“It’s a chicken-and-the-egg predicament,” Kraus says. “In the immediate future, this new test will help identify people with high risk of progressive disease—those likely to have both
pain and worsening damage identified on X-rays—who should be enrolled in clinical trials. Then we can learn if a therapy is beneficial.”
Kraus and colleagues isolated more than a dozen molecules in blood associated with the progression of osteoarthritis, which is the most common joint disorder in the United States. It afflicts 10 percent of men and 13 percent of women over the age of 60 and is a major cause of disability.
With further honing, the researchers narrowed the blood test to a set of 15 markers that correspond to 13 total proteins. These markers accurately predicted 73 percent of progressors from nonprogressors among 596 people with knee osteoarthritis.
The prediction rate for the new blood biomarker was far better than current approaches. Assessing baseline structural osteoarthritis and pain severity is 59 percent accurate, while the current biomarker testing molecules from urine is 58 percent accurate.
The new, blood-based marker set also successfully identified the group of patients whose joints show progression in X-ray scans, regardless of pain symptoms.
“In addition to being more accurate, this new
biomarker has an additional advantage of being a blood-based test,” Kraus says. “Blood is a readily accessible biospecimen, making it an important way to identify people for clinical trial enrollment and those most in need of treatment.”
The National Institutes of Health funded the work.
