What Causes Rheumatoid Arthritis?

Rheumatoid arthritis (RA) happens when your body’s defenses -- your immune system -- targets your joint linings. It’s a long-term condition that also affects other tissue, but the joints are usually the most severely affected. This is different from osteoarthritis, a condition caused by wear and tear on joints.

Doctors don’t know exactly what causes RA. It may be a combination of genes and environment. Some researchers think an infection with a bacteria or virus can trigger the disease in some people, but so far, they don’t know what virus or other organism does that.

As it develops, some of the body's immune cells start to attack healthy tissue, mistaking it for an invader. This triggers a chain reaction that leads to inflammation and damage.

The main target is the synovium, the thin layer of tissue that lines the joints. The inflammation also spreads to other areas in the body, which can cause ongoing pain, fatigue, and other problems.


What Makes Me More Likely to Get Rheumatoid Arthritis?

RA is more common in women than men. It’s more likely in women who've never been pregnant and those who've recently given birth.

The condition can also run in families.

RA becomes more likely with age, but it’s not a normal part of aging.

Can I Do Anything to Prevent It?

There’s no known way to prevent RA, but scientists are studying DNA markers that show that someone will develop it. They hope one day to find the trigger and prevent the disease.

If you smoke, quit. That’s the one sure thing besides your genes that can increase your chances of getting RA. Some studies show it also can make it progress faster and lead to more joint damage.

You also may be able to lower your chances by losing weight, especially if you’re 55 or younger. People who are overweight seem to have a higher risk of developing RA.

And new research shows there may be a link between RA and periodontal (gum) disease. So there’s another good reason to brush and floss and see your dentist for regular checkups.

Even though there’s nothing you can do to ensure you won’t get it, keep in mind that early treatment can make your symptoms less painful and save your joints from damage. Ideally, you should begin treatment within 3 to 6 months of your first symptoms.


WebMD Medical Reference Reviewed by David Zelman, MD on June 22, 2016



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