Neither PsA nor RA are very common diseases. PsA affects approximately 1.5 million people in the United States, but
RA is two to three times more common in biological females compared to males. PsA affects both sexes equally.
Here are some important differences between PsA and RA:
PsA | RA |
often asymmetrical | usually symmetrical |
commonly in the outermost finger joints and spine | commonly in the wrists and joints where the fingers and hand meet |
enthesitis is common | can cause low grade fever |
related to psoriasis | can cause rheumatoid nodules under the skin |
can affect the nails and eyes | circulating autoantibodies usually present |
affects the sexes equally | more common in biological females |
Find out the most commonly affected joints in psoriatic arthritis here.
The main symptoms of PsA and RA are similar. They both cause joint pain, swelling, and stiffness. However, the joints they affect can be different.
PsA is a spondyloarthritis, meaning it often affects the spine. RA is not.
RA can affect any joint, but the wrists, hands, and feet are the
Other common psoriatic arthritis symptoms
Other common symptoms of PsA can include:
- enthesitis, which is inflammation at the sites where ligaments and tendons connect to bones
- fatigue
- nail pitting or other changes
- psoriasis, which is scaly inflamed skin patches usually on the elbows, knees, or scalp
- fingers and toes appearing sausage-like
- uveitis, which is eye inflammation causing redness and pain
Learn how to monitor five PsA symptoms here.
Other common rheumatoid arthritis symptoms
Other common symptoms of RA can include:
- anemia
- appetite loss
- fatigue
- low grade fever
- rheumatoid nodules, which are firm lumps under the skin commonly on the elbows or hands
Learn more about RA symptoms here.
Both PsA and RA are autoimmune diseases. This means the immune system mistakenly attacks the body’s own tissues as if they were foreign invaders. In PsA and RA, the joints are the main target of this abnormal immune response.
People who study these diseases do not have a clear understanding of why this overreaction occurs. In both cases, it is likely a combination of genetic and environmental factors. Both diseases are more common in people who have a family history of them. In PsA, about 40% of people have a close relative with either psoriasis or psoriatic arthritis.
Other psoriatic arthritis risk factors
- infection
- joint injury
- obesity
- stress on joints
Psoriasis is another major risk factor for PsA. About 30% of people with psoriasis will develop PsA. It usually starts within 10 years of a psoriasis diagnosis. However, some people get PsA first and may not develop psoriasis.
Other rheumatoid arthritis risk factors
- assigned female at birth
- gum disease
- occupational exposure to dust
- smoking
- viral or bacterial infections
Learn about the link between gum disease and RA here.
The process of diagnosis starts with a medical history and exam. There are often
For example, having spine or skin involvement would point to PsA and not RA. Having symmetric joint problems would point to RA and not PsA.
Because there is not a specific test for either disease, diagnosis is mainly about
- anticyclic citrullinated peptide antibody (anti-CCP or ACPA), which are antibodies that are
usually Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source present with RA but not with PsA - complete blood count to check blood cell levels
- C-reactive protein, which is a marker of inflammation
- erythrocyte sedimentation rate, which is another marker of inflammation
- rheumatoid factor (RF), which is another antibody that people with RA often have
Imaging exams are useful for finding joint damage. They can see which joints show signs of damage and how severe the damage is. They can also reveal clues, such as enthesitis, which may tip the diagnosis one way or the other.
There is no cure for either PsA or RA, but effective treatments can improve symptoms and the ability to do daily activities. Treatment can also
- nonsteroidal anti-inflammatory drugs, such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn)
- biologics, which target the immune system to tamp down its activity
- corticosteroids for RA for short-term symptom control (these are avoided in PsA)
- disease-modifying antirheumatic drugs (DMARDs), such as methotrexate (Rheumatrex, Trexall), which can slow joint damage
- Janus kinase (JAK) inhibitors, which doctors may use for PsA or RA that does not improve
RA can be very disabling due to the amount of joint damage it can cause. When damage is severe, doctors may recommend surgery. Joint repair or replacement may help some people return to daily activities.
Left untreated, both PsA and RA can progress to permanent joint damage. They can both also lead to problems outside the joints with other
Early treatment using combinations of medicines is effective in stopping disease progression for many people. In addition, people who are active in their own care tend to have a better quality of life. Self-care is an important part of managing these disease. Strategies include:
- eating a nutritious, balanced diet
- exercising when you feel good to maintain muscle strength and joint function
- maintaining a moderate body weight
- managing stress with relaxation techniques and periods of rest
- staying socially connected and seeking support through a community PsA or RA group
- stopping smoking, which may
improve Trusted Source National Institute of Arthritis and Musculoskeletal and Skin Diseases Governmental authority Go to source symptoms
Talk with your doctor before starting an exercise program or making major dietary changes.
PsA and RA are similar autoimmune forms of arthritis. They share some of the same symptoms and common treatments. However, there are some key differences, especially with symptoms. These differences can help doctors narrow down the diagnosis of these diseases.
People with either disease can benefit from being involved in their own care. Healthy lifestyle habits are an important complement to treatment with medications.