Osteoarthritis, the most common form of arthritis, is difficult to diagnose early. Osteoarthritis affects over 32 million adults in the United States alone, causing symptoms of pain, aching, stiffness, decreased range of motion, and swelling. Osteoarthritis can impact a person’s ability to do daily tasks or go to work.
There are also no medications to cure osteoarthritis. Scientists know that generally, osteoarthritis causes the joints to break down and the underlying bone structure to change. Though there are medications available to manage pain and inflammation, there are none that prevent the progression of the disease. One critical component of drug development is the existence of a biomarker, or a character of the disease that can be measured. Biomarkers are integral to drug development because they allow researchers to measure the effects of drugs during clinical trials.
A new study published in Arthritis and Rheumatology pinpoints a protein called cartilage acidic protein-1 (CRTAC1) as a biomarker for osteoarthritis. The researchers examined the level of CRTAC1 in plasma in over 54,000 individuals from the UK Biobank. They found that high levels of CRTAC1 were strongly associated with knee and hip osteoarthritis.
The researchers also noticed that high levels of CRTAC1 were correlated with a need for joint replacements (either knee or hip replacements). No such correlation was found with inflammatory joint diseases, showing that CRTAC1 is a biomarker specific to osteoarthritis.
Among the 1,462 plasma proteins that were investigated in this study, CRTAC1 was the strongest indicator of osteoarthritis. The identification of a biomarker for osteoarthritis is an important landmark in the development of effective therapies and diagnostics for this disease.
There are currently no early methods available to diagnose osteoarthritis. Clinicians rely on laboratory imaging to diagnose osteoarthritis, and this is typically only done once the disease has already begun to cause symptoms. Scientists hope that the identification of this biomarker will lead to the development of treatments and early intervention for osteoarthritis.