Rheumatoid Arthritis (RA) Complications
Heart and Blood Vessel Disease
Some people with rheumatoid arthritis have a collection of fluid between the pericardium and the heart itself (called a pericardial effusion), but not all will have clinical symptoms from it. Episodes of pericarditis (inflammation of the membrane that surrounds the heart) usually develop during flares, or periods of heightened disease activity.
Persistent pericarditis can lead to thickening and tightening of the membrane, which can interfere with the heart's ability to work properly. Lesions similar to rheumatoid nodules can also develop on the heart and affect heart function. Inflammation of the heart muscle itself (myocarditis) is a rare complication.
Systemic inflammation puts people with RA at increased risk of cardiovascular disease. Recent research shows that people with RA have an increased risk of heart attack that is about the same as for people with type 2 diabetes. Having RA also increases risk of stroke.
Inflammation of blood vessels, called vasculitis, is an uncommon but serious complication of rheumatoid arthritis. Vasculitis associated with RA, called rheumatoid vasculitis, more commonly affects the small blood vessels supplying the skin, but it can affect many of the body's organs, including the eyes, heart, and nerves.
Diseases of the Blood and Blood-Forming Cells
Most people with active RA experience a reduction in red blood cells called anemia. Anemia may cause symptoms such as fatigue, rapid heart beat, shortness of breath, dizziness, leg cramps, and insomnia. Active inflammation may also lead to high levels of blood platelets, while treatment to suppress the immune system may lead to low levels of blood platelets, a condition called thrombocytopenia.
Another possible, but uncommon complication of RA is Felty's syndrome, a condition in which the spleen is enlarged and the white blood cell count is low in people with rheumatoid arthritis. Having Felty's syndrome may increase the risk of lymphoma, a cancer of the lymph glands.
The inflammatory process that affects the lining of the heart can similarly affect the membrane lining the lungs, leading to pleuritis and fluid collection.
Rheumatoid nodules also can form in the lungs. In most cases, the nodules are harmless, but they can lead to problems such as a collapsed lung, coughing up blood, infection, or pleural effusion -- the accumulation of fluid between the lining of the lung and the chest cavity. Finally, interstitial lung diseases and pulmonary hypertension can also develop as complications of RA.
RA treatments can affect the lungs, as well. For example, one of the most commonly used RA treatments, methotrexate, can potentially cause lung problems, characterized by shortness of breath, cough, and fever. Symptoms tend to improve when methotrexate is stopped.
Susceptibility to Infection
People with RA are more prone to infections, which may be related to the underlying disease itself or the immune-suppressing medications used to treat it. Studies show that treatment with biologic agents, a relatively new and effective class of RA treatment, may greatly increase the risk of serious infections in people with RA.