Arthritis linked to weak immune system

According to a study published in the Proceedings of the National Academy of Sciences (vol. 97, no. 16), researchers at the Rochester, MN-based Mayo Clinic have identified premature aging in the immune systems of patients with rheumatoid arthritis. This finding reverses the earlier belief that these patients have overactive immune systems.

According to the study, which was conducted with rheumatology patients treated at Mayo Clinic and included 51 patients with rheumatoid arthritis and 47 healthy controls, people with rheumatoid arthritis have immune systems that are prematurely exhausted.

Because normal immune cells are not produced properly, existing cells clone themselves and begin attacking the body instead of protecting it against infection.

"This study shows for the first time that patients with rheumatoid arthritis have prematurely aged immune systems," said Cornelia Weyand, a Mayo Clinic rheumatologist and the principal author of the study. "And because of that, we have aggressively treated the symptoms of rheumatoid arthritis with medications that suppress the immune system. While this practice offers relief of the painful symptoms, it also puts patients at greater risk for infections and cardiovascular disease – the two leading causes of death among these patients."

Weyand said that the new treatment options should be approached with caution. "… Physicians need to closely evaluate the status of a patient's immune system before choosing a medication and dosage. By doing this, we can suppress the immune system as little as possible and protect the patient's ability to respond to infections as much as possible," said Weyand.

"Future research may show if a prematurely aged immune system causes rheumatoid arthritis, or if the immune system prematurely ages because of rheumatoid arthritis," said Weyand. "When we learn this, we can determine if regenerating the immune system will prevent or alleviate problems associated with rheumatoid arthritis." PR