What do psoriasis and psoriatic arthritis (PsA) have in common? Both are autoimmune diseases. Psoriasis affects the skin and nails. Psoriatic arthritis (PsA) causes sore, stiff, and swollen joints.
Psoriasis and psoriatic arthritis are separate conditions. But sometimes they overlap.
If your doctor has already diagnosed you with psoriasis, you might wonder if you're destined to get PsA, too. Not necessarily. Around 30% of people with psoriasis will eventually get PsA. The other 70% won't.
The more you know about these two related conditions, the better you'll understand your risk of PsA, and the more prepared you'll be to deal with arthritis if you are diagnosed.
What's the Connection Between Psoriasis and PsA?
PsA is a type of arthritis that affects some people with psoriasis. Both psoriasis and PsA start from an overactive immune system. Inflammation is the common factor in both diseases.
In psoriasis, your immune system creates inflammation in your skin and causes skin cells to divide too quickly. Those extra cells pile up and form scaly, itchy patches called plaques. PsA causes your immune system to also attack and produce inflammation in your joints. That inflammation causes joint swelling, pain, and stiffness. Doctors refer to psoriasis and PsA together as "psoriatic disease."
Most people develop psoriasis first. Joint symptoms might not show up until 10 years or more after skin symptoms. Less often, PsA symptoms appear first or the two conditions start at the same time. A small number of people with PsA never get psoriasis, but most of them have family members with psoriasis or PsA.
Both psoriasis and PsA cause episodes called flares. These are periods when your symptoms get worse. Often something triggers a flare, such as:
- Stress
- An infection
- Alcohol or tobacco use
- A lack of sleep
- Temperature changes
A flare can last for weeks or months. Then you enter a symptom-free period known as a remission. Getting on the right treatment can help put psoriasis and PsA into remission and keep you there long-term.
Symptoms Psoriasis and PsA Have in Common
Sore, stiff joints are unique to PsA, but both conditions can share these symptoms:
- Patches of white or silvery scales called plaques on the skin
- Dry, itchy skin
- Pitted, cracked, or crumbling nails
- Eye pain, redness, and blurred vision called uveitis
Because both of these conditions cause visible symptoms, they can affect your self-esteem and quality of life. They might also affect your overall health. Having psoriasis, PsA, or both could put you at higher risk for obesity, high cholesterol, and type 2 diabetes.
Could Having Psoriasis Put You at Risk for PsA?
Once you're diagnosed with psoriasis, it's impossible to predict whether you'll get PsA. A combination of genes and factors in the environment cause both diseases. In general, the severity and activity of рѕoriаsiѕ is not strongly correlated with arthritic involvement. But you might be at higher risk for PsA if you have:
- Severe psoriasis, which means scales cover more than 10% of your body
- Psoriasis in your nails, scalp, or in places where skin rubs together, like your armpits and groin
- Family members with PsA
- Joint, neck, or back pain
- A high body mass index (BMI)
Researchers are studying gene changes linked to these two conditions. They hope that genetic tests might one day help predict which people with psoriasis will develop PsA.
Diagnosing PsA When You Have Psoriasis
If you have psoriasis and you start having joint pain, it might not be PsA. You could have osteoarthritis, rheumatoid arthritis, or another type of arthritis. Because many types of arthritis share the same symptoms, it's important to get the right diagnosis.
You may already see a dermatologist to treat your psoriasis. To diagnose and treat PsA, you'll probably see a rheumatologist, too.
Tests like these can help your rheumatologist figure out which type of arthritis you have:
- Blood tests. These tests check for conditions like rheumatoid arthritis or excluding other conditions that have the same symptoms as PsA.
- X-ray. This test uses a small amount of radiation to show changes in your joints.
- Ultrasound. It uses sound waves to make pictures of your joints.
It's important to get a diagnosis quickly. The sooner you start on a PsA treatment, the less likely you'll have joint damage.
Are the Severity of Psoriasis and PsA Linked?
Having severe psoriasis could increase your risk of getting PsA. But if you already have both conditions, one could be more severe than the other. You might have very few psoriasis scales but a lot of sore joints, or a lot of scales but few sore joints.
How to Treat Psoriasis and PsA Together
The goal of treatment is something called “treat to target” in which medications are adjusted every 3 months or so until you achieve remission or low disease activity.
Treatments like these stop skin cells from multiplying as quickly:
- Topical gels or creams like corticosteroids, vitamin D analogs, retinoids, and calcineurin inhibitors
- Light therapy
- Systemic treatments like corticosteroids, retinoids, and disease-modifying antirheumatic drugs (DMARDs) such as methotrexate and biologics
Psoriatic arthritis treatments include:
- Nonsteroidal anti-inflammatory drugs (NSAIDs)
- Conventional DMARDs like methotrexate and sulfasalazine
- Biologic drugs
- Oral targeted therapies
Some biologic medicines are approved to treat both psoriasis and PsA. These drugs both clear skin and slow joint damage:
- Adalimumab (Humira)
- Apremilast (Otezla)
- Etanercept (Enbrel)
- Infliximab (Remicade)
- Secukinumab (Cosentyx)
- Ustekinumab (Stelara)
Show Sources
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SOURCES:
American Academy of Dermatology: "Psoriatic Arthritis: Diagnosis and Treatment."
Arthritis Foundation: "Expert Q&A: PsA Without Psoriasis?"
Cleveland Clinic: "Psoriasis," "Ways to Prevent Psoriatic Arthritis Flare-Ups."
Current Rheumatology Reports: "From Psoriasis to Psoriatic Arthritis: Insights from Imaging on the Transition to Psoriatic Arthritis and Implications for Arthritis Prevention."
Federal Practitioner: "Management of Psoriasis and Psoriatic Arthritis in a Multidisciplinary Rheumatology/Dermatology Clinic."
Indian Dermatology Online Journal: "Body Image, Self-Esteem, and Quality of Life in Patients with Psoriasis."
JAAD International: "Diabetes and Obesity Burden and Improvements in Cardiometabolic Parameters in Patients with Psoriasis or Psoriatic Arthritis Receiving Apremilast in a Real-World Setting."
Johns Hopkins Medicine: "Psoriatic Arthritis."
Journal of Clinical and Aesthetic Dermatology: "Psoriasis and Psoriatic Arthritis."
Mayo Clinic: "Psoriasis," "Psoriatic Arthritis."
National Institute of Arthritis and Musculoskeletal and Skin Diseases: "Psoriasis," "Psoriatic Arthritis."
National Psoriasis Foundation: "About Psoriatic Arthritis," "Psoriasis Statistics," "Understanding Psoriatic Disease."
Psoriasis Forum: "Which Psoriasis Patients Develop Psoriatic Arthritis?"
Rheumatology and Therapy: "Usage of C-Reactive Protein Testing in the Diagnosis and Monitoring of Psoriatic Arthritis (PsA): Results from a Real-World Survey in the USA and Europe."
StatPearls: "Psoriatic Arthritis."
