Imagine soldiers getting orders to turn on their own country, its cities and its citizens. It doesn’t make sense for defenders to attack the very things they are supposed to protect. However, that’s exactly what happens when you have rheumatoid arthritis (RA). In RA, your immune system, which is designed to protect you, turns against you, attacking your joints and tissues. Understanding Rheumatoid Arthritis RA is an autoimmune disorder. In RA, your immune system targets the thin membrane that lines the joints, called the synovium. As a result, your joints become inflamed and ache. Some people with RA develop nodules—lumps of tissue that form under the skin. RA can affect many different joints and can damage cartilage, tendons, ligaments, and cause bone loss. You usually feel symptoms in your hands, wrists, feet and knees first. RA is also symmetrical, meaning that it affects joints on both sides of your body. When a joint on your right side has RA, the corresponding joint on your left side will usually have it too. Your organs can also be affected by RA. Left untreated, people with RA can suffer joint deformity and disability. What Causes Rheumatoid Arthritis? Researchers aren't sure why your immune system attacks itself. They know that certain immune cells called T cells send flawed signals to the rest of your immune system. These signals cause your immune system to continually overreact. The result is inflammation and pain in your joints. Factors that may trigger the faulty immune response in RA include: Environmental influences such as infections and smoking. Scientists believe that infections can trigger RA in some people. However, they haven’t been able to identify any one specific organism that triggers RA in all people. Researchers have also found that smoking is strongly linked to RA. If you smoke, your risk of developing RA increases greatly. Genetics. It’s possible for RA to run in families. Parents can pass along genes that make their children more prone to RA. These genes are called HLA genes. If you have certain forms of HLA genes, you have a greater risk of getting RA or having severe RA. Keep in mind that having these HLA genes doesn’t mean that you will get RA. It means that you have a higher risk. Your doctor can test a sample of your blood to see if you have the particular HLA genes linked to RA. Hormones.Sex hormones might play a role in triggering RA. Women are more likely to develop RA, although men can get RA too. Women between the ages of 25 and 55 years have the highest risk. It’s less common in later years when sex hormone levels fall. What’s more, RA tends to get better during pregnancy and flare right after childbirth. Also, RA is not as common in women who take birth control pills. Can Rheumatoid Arthritis Be Cured? There is no cure for RA. It is a chronic disease that must be managed throughout your lifetime. Many people with RA experience fluctuations in their symptoms—intermittent bouts of worsening of symptoms followed by few symptoms (remission). Some people have constant symptoms that get worse with time. If you have joint pain and stiffness, talk to your healthcare provider. Even mild joint pain should be looked at by a doctor. Early diagnosis and treatment of RA is important to prevent irreversible joint problems.