With a blood test, doctors may one day treat rheumatoid arthritis before it starts, preventing long-term joint damage.

Imagine being treated for rheumatoid arthritis years before the onset of your first symptom – thus stopping the disease in its tracks.  Researchers from University Hospital in Umea, Sweden, analyzed the blood samples of 342 people, 86 of whom went on to develop rheumatoid arthritis, RA, up to five years after giving blood. When compared with blood samples from the 256 who remained healthy, the RA group showed increased levels of cytokines and other factors related to inflammation years before the diagnosis of rheumatoid arthritis.This is important because “when a patient with RA comes in now, their immune system is on fire.  This will help unlock the pathway involved in how this disease occurs, and may open up new early treatment opportunities, “says Dr. Richard Keating, M.D., a professor of rheumatology at the University of Chicago.

An estimated 1.3 million Americans are affected by rheumatoid arthritis, an autoimmune disease that attacks the joints, causing pain and inflammation, and eventually leading to the destruction of cartilage and bone.  Treating RA early and aggressively with a combination of drugs has been shown to have the best chance of preventing long-term joint damage.

In the future, a blood test that warns of RA could help doctors assess the severity of individual cases and predict which medications might be most effective for which individuals.  This approach has been used with success in treating other diseases, including some types of cancer.

As promising as the study appears, having patients undergo a routine blood screening for RA is not yet practical.  One problem with the study is that many of the inflammatory markers measured in the screening are not specific to RA.  Diseases like lupus or fibromyalgia or even a viral infection can mimic the immune system activation shown by the blood test.

Although the practical application may be years away, the study is exciting news for RA sufferers and their families.  It “moves the whole field along,” says rheumatologist Dr. Lionel Ivashkiv, M.D., an associate chief scientific officer at the Hospital for Special Surgery, in New York City. “In the future, in combination with other tests and risk factors–such as genetics, smoking, and family history–we can maybe predict who is at high risk for developing RA.”