If you develop painful, swollen and stiff joints, you may have one of several potential causes of joint inflammation. That cause is rheumatoid arthritis for as many as 1.5 million Americans, the Arthritis Foundation estimates.
“Rheumatoid arthritis can be diagnosed in people in their 20s, 30s, 40s, or even later in life,” says Cleveland Clinic rheumatologist Soumya Chatterjee, MD. It’s more common in women than men. Smoking raises the risk twofold to fourfold (depending on how much you smoke), increasing both the likelihood of developing rheumatoid arthritis and having more severe disease.
What Is Rheumatoid Arthritis?
Rheumatoid arthritis, or RA, is an inflammatory autoimmune disease. The body’s immune system mistakenly attacks healthy tissues (primarily the tissues lining joints) with ongoing inflammation.
This process causes joint pain, swelling, redness and stiffness. It often affects multiple joints, particularly those in the hands and feet. Other joints that can be affected are the wrists, elbows, shoulders and knees.
RA also has been linked to health problems beyond the joints. It’s associated with increased cardiovascular risk, including a greater likelihood of heart attack and stroke. In fact, expert guidelines have identified rheumatoid arthritis as a risk-enhancing factor to consider when deciding whether to begin cholesterol-lowering statin therapy for cardiovascular risk reduction. Furthermore, rheumatoid arthritis can cause extra-articular manifestations that can adversely affect the lungs, eyes, gastrointestinal tract, kidneys, bones, and, potentially, cognitive and emotional health.
What Are the 4 Stages of Rheumatoid Arthritis?
Experts have identified four stages of rheumatoid arthritis. It’s important to note that the speed at which individuals progress through these stages varies—for some, it may take many years— and not everyone with RA progresses through all four stages.
- Stage 1: Tissue inflammation around the joint, as well as some joint pain and stiffness and fatigue. At this stage, no damage to the bones is evident on X-rays.
- Stage 2: Inflammatory damage to the joint cartilage, fatigue, and stiffness and reduced range of motion in the joint.
- Stage 3: Severe inflammation that causes bone damage, as well as increased pain, stiffness, and loss of joint range of motion. Physical changes (e.g., joint deformity) may become evident.
- Stage 4: Severe pain, stiffness, swelling and loss of mobility.
Rheumatoid Arthritis Diagnosis
“With rheumatoid arthritis, uncontrolled inflammation leads to joint damage, which is potentially not reversible,” says Dr. Chatterjee. “That’s why we don’t want to take too long to make the diagnosis, because the longer it takes to diagnose, the more joint damage is done.”
An array of medications suppress some of the processes that produce the damaging inflammation of RA. Advances in treatment with these disease-modifying drugs have dramatically improved the outcomes for people with the disease. “We can do much better now than we could decades ago,” Dr. Chatterjee says. However, early and accurate diagnosis is essential to start treatment early to prevent irreversible joint damage and disability.
Making a rheumatoid arthritis diagnosis requires clinical judgment based on a thorough medical history, physical examination, laboratory tests and X-rays. Physicians must rule out conditions with similar symptoms, such as infectious arthritis (often caused by viruses), other autoimmune diseases (such as lupus or psoriatic arthritis), gout or pseudogout.
Your doctor will start by looking for characteristic rheumatoid arthritis symptoms (see sidebar). The next step is blood tests to look for antibodies and markers of inflammation.
One antibody is rheumatoid factor (RF), which is often positive in people with rheumatoid arthritis but can also be seen in other conditions or even in healthy people. A more specific test looks for anti-cyclic citrullinated protein (anti-CCP) antibodies. Elevated levels of inflammatory markers such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) indicate the likelihood of an inflammatory condition, such as RA.
Imaging studies may also be done. Early in the disease, X-rays may appear normal. “It takes time for joint damage to be visible,” says Dr. Chatterjee.
However, X-rays of the hands and feet are performed at diagnosis to provide a baseline for future comparison. Joint space narrowing or erosions (holes on the margins of the bones) that appear on X-ray at the time of diagnosis indicate a more aggressive disease.
Ultrasound and MRI scans are not routinely used to make a rheumatoid arthritis diagnosis, but they can be helpful in detecting subtle joint inflammation (synovitis) that is not apparent on a physical examination.
Classification Criteria
No single test is definitive. “You can have positive RF and not have rheumatoid arthritis,” says Dr. Chatterjee. “Less commonly, you can have positive anti-CCP antibody and not have rheumatoid arthritis.” The diagnosis must be made by interpreting test results in the context of symptoms and signs of the disease.
The American College of Rheumatology and the European Alliance of Associations for Rheumatology have established classification criteria to aid in the diagnosis of rheumatoid arthritis. These criteria assign scores based on the number and type of joints involved (more joints and specific joint patterns increase the score), duration of symptoms, presence of RF and anti-CCP antibodies and elevated CRP or ESR. A higher total score increases diagnostic certainty.
