Psoriatic Arthritis Vs. Rheumatoid Arthritis: How the 2 Conditions Differ, According to Experts

Both are the result of an overactive immune system—but some of their symptoms and risk factors can be quite different.

By Sarah Bradley

July 27, 2021
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CREDIT: GETTY IMAGES

People often use an arthritis diagnosis as an umbrella term to mean any kind of painful joint condition, but there are actually several different kinds of arthritis across a few different "families," so to speak.

While some forms of arthritis, like osteoarthritis, are degenerative, occurring with age, wear and tear, or injury, there are two types that are autoimmune (i.e. a condition where your immune system mistakenly attacks your own healthy cells): rheumatoid arthritis (RA) and psoriatic arthritis (PsA).

But even though RA and PsA are both autoimmune diseases, they are still two different conditions with their own causes, symptoms, and treatments. Here's what you need to know about the similarities and differences between these two rheumatic conditions.

What's the difference between psoriatic arthritis and rheumatoid arthritis?

RA and PsA are both inflammatory conditions that affect people in the same age group (between 30 and 60 years old) and are often symmetrical, which means symptoms affect the joints on both sides of the body, rheumatologist Vinicius Domingues, MD, medical advisor to CreakyJoints, tells Health. Both conditions are also the result of an overactive immune system—one where your body attacks the joints and causes pain, stiffness, and swelling.

Many symptoms are the same between the two diseases—and treatments often overlap as well—but the main difference is where those symptoms are located. People with PsA, for example, often have symptoms in the distal joints of their fingers and toes, whereas people with RA suffer in their middle joints. PsA also affects more than just your joints, often attacking your eyes, skin, nails, and tendons.

What are the causes of psoriatic arthritis and rheumatoid arthritis?

We don't have an understanding of what causes many autoimmune conditions, including RA and PsA, but there are common links among people who develop these diseases.

"We don't know exactly what causes RA or PSA, but we do know there are genetic components and stress components to both," Magdalena Perez-Rivera, MD, rheumatology specialist with Conviva Care Centers tells Health.

Here are some of the primary risk factors for RA and PsA—you'll see there is a good amount of overlap.

Risk factors for psoriatic arthritis

  • Psoriasis (about 30 percent of people with this inflammatory skin condition go on to develop PsA)
  • Genetics
  • Stress
  • Smoking
  • Infections (bacterial or viral)
  • Obesity

Risk factors for rheumatoid arthritis

  • Genetics
  • Stress
  • Gender (RA is more common in females)
  • Smoking
  • Poor dental health
  • Hormones changes or abnormalities
  • Obesity

How do the symptoms of psoriatic arthritis and rheumatoid arthritis compare?

The symptom profile for these two arthritic conditions is actually where they differ the most. Although joint pain, stiffness, and swelling are the most typical symptoms for both RA and PsA, that's where their similarities end—and even with that, the way joint symptoms are experienced can be pretty different.

SYMPTOM RA PSA

Rash

Sometimes; nodules and vasculitis

Yes, if you have psoriasis; itchy, red patches and/or thick, painful scales

Joint pain

Yes; most often in middle joints; often starts in fingers and toes, then moves to knees, hips, ankles, etc.

Yes; most often in distal joints of fingers and toes

Joint swelling/stiffness

Yes; may be worse first thing in the morning

Yes; joint swelling in fingers and toes can cause "sausage digits"

Fatigue

Yes

Yes

Back pain

Sometimes

Yes; can be severe and may spread into pelvis

Tendon inflammation

No

Yes; enthesitis is common in the areas where tendons connect to bones

Changes to nails

No

Yes; pitting, flaking, and separation of the nail from the nail bed

Symmetrical

Yes

Yes, but can also be asymmetrical

Changes to eyes/vision

Yes; uveitis is common

Yes; uveitis is common

How are psoriatic arthritis and rheumatoid arthritis diagnosed?

Unfortunately, there's enough overlap between these two conditions that diagnosis can be a little difficult, though a doctor may be able to know right away which kind of arthritis is affecting their patient.

For example, Dr. Domingues notes that the distal joints (i.e., the ones closest to the tips of your fingers and toes) aren't affected in RA, so asking a patient about where they experience pain can be a useful tool. Likewise, if a patient has diagnosed psoriasis or crumbling, pitting nails and visits their doctor complaining of new joint pain, they probably have PsA, not RA.

Just as often, however, further testing is needed to truly determine whether the cause of symptoms is RA or PsA.

"The good thing about RA is there are blood tests that can help us diagnose, but they aren't terribly helpful with psoriatic arthritis," says Dr. Domingues. "There's no gene or blood test for PsA, but inflammatory markers can be elevated in both conditions."

Radiology can also be helpful for diagnosing both conditions, Dr. Domingues explains: "Both x-rays and MRIs can allow us to see inflammation and bone issues [for RA and PsA]."

What does treatment look like for psoriatic arthritis and rheumatoid arthritis?

The main treatments for autoimmune arthritis conditions generally work for both RA and PsA; Dr. Domingues says most of the medications are used interchangeably and that non-pharmaceutical treatments, like physical therapy, also work well for both types.

Pharmaceutical treatments for RA and PsA:

  • Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen
  • Corticosteroids like prednisone
  • Disease-modifying anti-rheumatic agents (DMARDs) like methotrexate and hydroxychloroquine
  • Biologics, a more advanced type of DMARD that can stop or slow inflammation; these include Tumor Necrosis Factor-α (TNF) inhibitors and interleukin inhibitors (this is also where treatments for PsA and RA diverge a bit, with a few specific inhibitors working well for PsA but not RA and vice versa)

Non-pharmaceutical treatments for RA and PsA:

  • Physical therapy
  • Low-impact exercise
  • Smoking cessation
  • Topical analgesics
  • Ice and heat
  • Surgery

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What to know about your choices after an RA diagnosis.

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Getting a rheumatoid arthritis (RA) diagnosis can be overwhelming, but you don't have to panic. There are more treatments than ever to alleviate your symptoms, prevent worsening of your condition, and improve your quality of life.

Even better, your options span multiple categories of treatment, from medications and holistic remedies to physical therapy and surgery, meaning you can pick and choose with your doctor which treatments work best for you.

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"Rheumatoid arthritis is a destructive chronic disease that gets worse, but treatments stop the disease from [progressing] and can prevent long-term damage," Juan J. Maya, MD, rheumatologist at the Rheumatology Center of Palm Beach and medical advisor to CreakyJoints, tells Health.

In general, rheumatoid arthritis treatments fall into three categories: medication, surgery, and alternative therapies. We asked doctors to explain the most common treatment options for people with RA within these categories. Here are 12 of their picks.

OTC medications

These are often a frontline treatment for people who are in the early stages of RA or who have mild, ongoing symptoms. Nonsteroidal anti-inflammatory (NSAID) drugs like ibuprofen (Motrin) and naproxen (Aleve) can reduce inflammation and swelling without the side effects or potential for dependency of stronger drugs like opioids.

There are limitations, though, says Dr. Maya, since NSAIDs are simply pain relievers—they don't stop or treat the disease itself. And not everyone can use NSAIDs on a regular basis: People with kidney disease and stomach ulcers are often advised to avoid them, and even someone without coexisting conditions can suffer GI complications from overuse of NSAIDs.

Steroids

A course of steroid treatment with a drug like prednisone can be helpful for RA patients while they wait for more advanced medications to take effect. Steroids have the ability to reduce inflammation and suppress the body's immune response; they might be used to bring down acute swelling or sudden flares, and can be given orally, intravenously, or via injection.

However, steroids are not a long-lasting treatment because they come with the potential for serious side effects—especially at higher doses. These side effects include GI issues, mood swings, bloating and weight gain, and even osteoporosis. If your doctor prescribes you steroids for your RA symptoms, it will likely be with a plan to taper you off them or transition you to another treatment.

Disease-modifying antirheumatic drugs (DMARDs)

According to Dr. Maya, disease-modifying antirheumatic drugs are one of the most commonly used medications to treat RA. Not only can these drugs stop the progression of the disease, but they can also prevent it from damaging healthy tissue surrounding affected joints. Because they are a moderately strong drug, but not the top tier treatment, many newly diagnosed RA patients end up on DMARDs. Common ones include methotrexate and hydroxychloroquine.

In general, these drugs work by targeting the immune system pathways responsible for triggering the inflammatory response. They can take some time to become fully effective (often requiring the use of NSAIDs or steroids in the meantime to treat symptoms) but tend to work quite well once they reach their full potential. In many cases, your dosage of these types of medications will be small at first, and then slowly increase over time.

However, DMARDs do carry a set of side effects, including increased risk of infection, GI upset, headaches, and fatigue, and in rare cases, liver toxicity.

Biologics

Biologic response modifiers include drugs like adalimumab (Humira) and tofacitinib (Xeljanz). They work the same way as DMARDs, in the sense that they target your immune system, but the approach is more focused. They block inflammation in specific molecules, says Dr. Maya, stopping arthritis in its tracks.

That said, while biologics can be more effective and tend to work faster, they also carry a risk of infection and are more expensive than other treatment options. They are typically only available as injections or infusions, rather than oral pills.

Physical therapy

Rather than waiting for your RA to become debilitating—or until you're in recovery post-surgery—you might want to consider physical therapy.

According to Dr. John Gallucci Jr., DPT and CEO of JAG-ONE Physical Therapy, the relationship between rheumatologists and physical therapists is growing—and leading to more and more rheumatologists using physical therapy as an early intervention treatment.

"Physical therapy is not just exercise, but can decrease your pain, improve any restriction in range of motion, and help return you to normal function," he explains.

When you see a physical therapist for your RA symptoms, they will likely focus on three things, says Dr. Gallucci: function, flexibility, and strengthening. This might be done through a regime of physical exercises, for sure, but also use of electrical stimulation, heat, ice, and exercise equipment to increase circulation and blood flow to affected joints.

Joint replacement surgery

Joint replacement surgery removes a severely damaged joint—like that of the hip or knee, commonly—and replaces it with an artificial version. Surgery is not a first line of defense, obviously, but occasionally it's a necessity.

This procedure can help an RA sufferer experience less pain and more range of motion, but it's a fairly complicated procedure that also requires a long recovery period and a commitment to post-surgical physical therapy.

Surgery may be needed in a few situations, says Dr. Maya. "If patients can't be on [DMARDs or biologics] or have aggressive disease, like destroyed joints, then we will need a surgeon to repair the damage in those tendons or joints, or replace them completely," he explains.

Other surgeries

If your joints or tissue are inflamed or damaged but you don't need a full replacement, you may be able to undergo surgery to simply remove what's ailing you.

There are two types of removal surgery: arthrodesis, where a joint is removed and surrounding bones are fused together, and synovectomy, where inflamed tissue around a joint is removed.

These surgeries don't generally work as well as replacement procedures; they have a higher risk of symptom recurrence and often limit your range of motion. But in some cases, it may be a better option for you than a full replacement surgery. It may also be an option to repair a damaged joint, although this, too, isn't always effective.

Heat and ice

Whether heat or ice works better for inflamed joints depends on your preferences and what kind of relief you're looking for. Usually, heat is better for relaxing joints and soothing achy or tight muscles; on the flip side, ice can dull pain and often reduce swelling (though it won't last forever).

Like NSAIDs, this treatment doesn't actually target your RA itself, but can go a long way toward reducing pain without the use of OTC medications.

Exercise

When you're in pain, exercising might feel like the last thing you want to do, but Dr. Gallucci says that physical activity is crucial to keeping inflammation levels low, so you don't end up in pain in the first place.

"What decreases inflammation is blood circulation," he explains, "so [doing activities] like using an exercise bike or walking can increase your heart rate, which increases circulation and relieves the symptom of pain."

Relaxation and mindfulness

Tension and stress can contribute to painful symptoms of RA, not only because they leave you vulnerable to illness and injury but because they can disrupt your sleep cycles, influence your diet, and steer you away from healthy activities like exercise.

Learning to move your body in beneficial ways—through yoga and relaxation techniques—can help you prevent the natural worsening of joint pain and stiffness and practicing mindfulness and meditation can help train your brain to process stress in more productive ways.

While taking a yoga class or meditating for ten minutes every day won't make your RA disappear, living a more relaxed, tension-free life might go a long way towards limiting the overall progression of your disease. At the very least, it can't hurt—we all could benefit from a little less stress.

Topical creams

Many people turn to topical treatments to treat arthritis pain on the spot, and this isn't a bad thing—but you should know the limitations of this approach.

For example, it literally is an "on the spot" treatment, says Dr. Gallucci, and one that very rarely gets down deep enough to the source of the problem to provide long-lasting relief.

"These analgesics cause a histamine reaction to the nerve endings and give a feeling of warmth," he explains, "and most people prefer a feeling of warmth as opposed to one of pain."

However, studies have shown that while some of these topical treatments get past the skin barrier, most do not—so you're only masking your symptoms, not treating them, Dr. Gallucci adds.

Still, some people like having a fast relief option in the form of topical creams, like those including capsaicin, which also provides a warming sensation and can be used three or four times per day.

You might also want to consider using diclofenac (Voltaren), a topical NSAID that used to be prescription-only but is now available OTC; a 2020 review published in Rheumatology and Therapy found diclofenac to be similarly effective as other treatments in reducing pain, without the added GI side effects that come with oral NSAIDs.

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