July 30 (HealthDay News) -- Levels of a certain protein strongly predict the risk of hip and knee joint replacement as a result of severe osteoarthritis, a new study shows.

The research involved 912 healthy people in Italy, including 60 who had severe osteoarthritis that led to a knee or hip replacement between 1990 and 2005. Those with high levels of vascular cell adhesion molecule 1 (VCAM-1) at the start of the study were most likely to undergo joint replacement, the study found. VCAM-1 is expressed on cells in the cartilage and connective tissue.

"The level of VCAM-1 emerged as a significant predictor of the risk of joint replacement due to severe OA, equaling or even surpassing the effects of age," wrote Georg Schett, of the University of Erlangen-Nuremburg in Germany, and his colleagues.

They also found that including VCAM-1 levels in risk prediction models led to more accurate classification of patients.

The study, which appears in the August issue of Arthritis & Rheumatism, is the first to establish a laboratory biomarker for the risk of severe osteoarthritis, according to background information in a news release from the journal. Such biomarkers can lead to early diagnosis of the disease, before clinical symptoms appear. Improved prediction of severe osteoarthritis, experts say, could help identify people who would benefit from interventions such as weight loss, strength training and aerobic exercise.

The researchers said that learning more about the underlying mechanism in the link between VCAM-1 and osteoarthritis might also help improve understanding about the causes of the joint disease.

SOURCE: Arthritis & Rheumatism, news release, July 30, 2009