Rheumatoid arthritis (RA) is one of the most common causes of joint pain. In general, arthritis costs U.S. adults with the condition more than $303 billion per year in health care expenses and earnings loss from time off work. In RA, not only can the immune system attack one’s joints, but the condition can lead to other problems throughout the rest of your body.

Here are some facts about RA, including its effects, risk factors, treatments, and complications, as well as the condition’s overlap with other types of arthritis and chronic diseases.

Incidence and Prevalence of Rheumatoid Arthritis

• Around 23 percent of all adults in the United States — nearly 1 out of every 4 — have arthritis, which includes RA, osteoarthritis, and other joint-affecting diseases such as gout, lupus, systemic sclerosis, and fibromyalgia.
• Approximately 1.3 million adults in the United States are living with RA, or roughly half a percent of the population.
• RA is the most common autoimmune disease that affects the joints and causes joint pain.
• About 4 out of every 5 people living with RA are women.

Risk Factors for Rheumatoid Arthritis

• Being overweight or obese can worsen pain and other symptoms of RA, make treatments less effective, and increase the risks of complications such as heart disease.
• Weight loss can help improve RA symptoms and reduce the disease course.
• Many environmental factors and exposures can lead to higher risk of developing RA, including exposure to smoke as a child.
• Certain racial and ethnic groups, including Hispanic people, are at a greatly increased risk of developing RA or more severe RA-related complications than other ethnic groups.
• Women who have breastfed their infants have a lower risk of developing RA compared to women who have not breastfed.

Blood Tests for Rheumatoid Arthritis

• Although the vast majority of people with RA test positive in antinuclear antibody (ANA) blood tests, a positive result is not specific to RA. Results are found to be positive in most major autoimmune conditions — including lupus, which can also cause joint disease.
• The ANA test is sensitive, which means that while it is almost always positive among people with RA, it can also be positive in many healthy people without autoimmune disease. This is known as a false positive.
• A rheumatoid factor (RF) test is a more specific test for RA, compared to ANA, but it’s not as sensitive, meaning that a positive test highly suggests RA, while a negative test does not completely rule out RA.
• Cyclic citrullinated peptide (CCP) antibody tests are the most specific RA test and predict more severe disease.
• Many blood tests can be used in certain situations, such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) tests, which track disease activity (i.e., how your RA is progressing over time).

Symptoms of Rheumatoid Arthritis

• RA is not just limited to joints. It can be a systemic disease that affects multiple parts of the body, such as the heart, lungs, and bones.
• RA develops in a symmetrical pattern (affecting both sides of the body), meaning that it’s very unlikely that a person with RA has joint pain in one knee, for example, and not the other.
• Morning stiffness is one of the defining symptoms of RA, affecting up to 80 percent of people. This symptom distinguishes RA from the chronic pain found in osteoarthritis, where stiffness usually worsens throughout the day.
• RA symptoms can be mimicked by other autoimmune diseases (also called rheumatic diseases), such as lupus or systemic sclerosis.
• Many people with RA report having low-grade fevers that come and go.

Bones, Tendons, and Ligaments

• Having RA can cause decreased bone density over time, leading to brittle bones (osteoporosis) and increased risk of fractures and loss of height.
• Damage from RA can eventually spread from the joint space to surrounding tendons and ligaments, causing fingers and limbs to slowly become bent and lose their shape.

Lung

• Nearly 4 in 5 people with RA will have abnormal chest X-rays that suggest RA-related lung symptoms.

Other Symptoms

• RA can lead to Sjögren’s syndrome, which can affect your tear and salivary glands, resulting in chronic dry eyes and mouth and other complications — like more frequent cavities, eye damage, and infections.
• RA can cause hard nodules, called rheumatoid nodules, to form under your skin and elsewhere, including on your heart, lungs, or other organs.

Rheumatoid Arthritis Complications

• Cardiovascular (heart) problems are 50 percent more likely in people with RA compared to the general population and are one of the leading causes of death among people with RA.
• Other leading causes of death include cancer and infections, such as pneumonia (lung infection). RA drugs that target the immune system can increase these risks.
• The risk of some cancers among people with RA is doubled, potentially due to RA’s effects on the immune system. The immune system is normally supposed to help in detecting and killing cancer cells before they develop.

Treatments for Rheumatoid Arthritis

• Nonsteroidal anti-inflammatory drugs (NSAIDs) — like Advil (ibuprofen) and Celebrex (celecoxib) — are effective when taken once in a while for breakthrough joint pains. Long-term use, however, can increase your risk for heart attacks and stroke.
• Disease-modifying antirheumatic drugs (DMARDs) and biologics are the only drugs that actually slow down disease progression — including progressive joint damage and damage to other parts of the body. NSAIDs and steroids, by contrast, just alleviate symptoms.
• About 90 percent of people with RA will take methotrexate at some point in their lives.
• Advances in antirheumatic drugs have drastically reduced the need for certain types of joint replacements, such as shoulder and elbow replacements, while knee replacements have not significantly decreased.
• Occupational therapy and certain exercise routines, like aerobic exercise, resistance training, and aquatic routines, have been shown to improve chronic pain, fatigue, and ability to function for people with RA.

Talk With Others Who Understand

By joining myRAteam, you will become part of the social network for people with rheumatoid arthritis and their loved ones. On myRAteam, more than 151,000 members come together to ask questions, give advice, and share their stories with others who understand life with RA.

Do you have RA, or do you want to learn more about it? Share your thoughts in the comments below, or start a conversation by posting on myRAteam.