Connect with others who understand.

sign up log in
About MyPsoriasisTeam

Psoriatic Arthritis Causes

Posted on March 31, 2021
See how 656 members reacted on this article
Medically reviewed by
Ariel D. Teitel, M.D., M.B.A.
Article written by
Candace Crowley, Ph.D.

Psoriatic arthritis (PsA) is a complex disease with many possible causes and risk factors. PsA is a form of inflammatory arthritis that occurs in up to one‐third of people with psoriasis, causing joint damage in any part of the body. PsA commonly causes dactylitis (severe inflammation of the finger and toe joints), enthesitis (inflammation where tendons and ligaments attach to the bone), and spondylitis (inflammation of the spine).

What Causes Psoriatic Arthritis?

Psoriatic arthritis is an autoimmune disease, meaning the body’s immune system mistakenly attacks healthy cells and tissues, leading to damage and inflammation. In psoriatic arthritis, the immune system attacks the ligaments and joints, causing symptoms of psoriatic arthritis such as joint pain, stiffness, and swelling.

There is no known cause of psoriatic arthritis. However, rheumatologists and researchers believe psoriatic arthritis is triggered by a combination of biological and environmental factors.

Genetic Causes

Research has identified genetic factors associated with the development of psoriatic arthritis. Many of these genetic factors are involved in the abnormal function of the immune system. Activation of these genes is linked to joint inflammation, suggesting their role in PsA symptoms.

Immunological Factors

T cells, a type of immune cell, are heavily involved in psoriatic arthritis. These cells release proteins (called cytokines) that stimulate inflammation. This inflammation causes joint swelling, pain, and damage. Studies show that higher numbers or activity of these T cells and the cytokines they release are linked to PsA symptoms and severity. Several antirheumatic drugs work by turning down the immune response mediated by T cells and cytokines.

Many injectable drugs used in the treatment of psoriatic arthritis are inhibitors for immune mediators such as cytokines. For example, PsA drugs such as Humira (adalimumab), Enbrel (etanercept), and Remicade (infliximab) block the activity of a cytokine called tumor necrosis factor (TNF). By turning down the immune response mediated by TNF, these drugs ease PsA symptoms. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, also work by reducing pain from immune-mediated inflammation.

Environmental Causes

Research suggests that infections can overactivate the immune system, triggering an attack on healthy cells and tissues. Streptococcal throat infection (strep throat) is strongly linked to PsA.

Other environmental factors potentially involved in psoriatic arthritis include physical trauma, injuries, and work-related physical activities. The connection between injuries and trauma and the development of psoriasis and PsA is known as the Koebner phenomenon.

What Are the Risk Factors for Psoriatic Arthritis?

There are many risk factors for psoriatic arthritis. Although these risk factors have been associated with PsA, additional research is needed to determine why and how they contribute to disease.

Psoriasis

Psoriasis, a skin condition characterized by scaly lesions, is the most significant risk factor for psoriatic arthritis. However, people without skin psoriasis can also develop psoriatic arthritis. Psoriatic arthritis affects nearly 30 percent of people with psoriasis. Psoriatic arthritis most commonly begins about 10 years after skin psoriasis. In approximately 10 percent to 15 percent of people, psoriatic arthritis begins before skin psoriasis.

Severe psoriasis may increase the risk of PsA more than mild or moderate psoriasis does. People with psoriasis lesions or plaques on their nails (nail pitting), scalp, or genital region are also more likely to develop PsA.

Family History

Psoriatic arthritis runs in families. Nearly 40 percent of people with psoriatic arthritis have a family member with psoriasis or arthritis. The data suggests that genetics play a role in the development of psoriatic arthritis.

Race and Ethnicity

White people are at an increased risk of psoriatic arthritis compared to other ethnicities.

Medical Treatments

Although researchers don’t yet understand why, some medical treatments have been linked to PsA, including:

  • Antibiotic treatment for infections
  • Rubella vaccination
  • Recent corticosteroid use

Gender

Men and women are equally likely to develop psoriatic arthritis, so gender is not a risk factor. Although some studies have suggested a link between hormones and PsA, no definite connection has been proven.

Age

PsA can occur at any age. Psoriatic arthritis usually appears between the ages of 30 and 50, although children with psoriasis are also at risk.

Other Environmental Factors

Other health and environmental factors can increase the risk of PsA, including:

  • Obesity, especially at age 18
  • Smoking
  • High cholesterol
  • Frequent oral ulcers
  • Moving to a new house
  • Lifting heavy loads at work

Talk With Others Who Understand

MyPsoriasisTeam is the social network for people with psoriasis and psoriatic arthritis, and their loved ones. More than 90,000 members come together to ask questions, give advice, and share their stories with others who understand life with psoriasis and psoriatic arthritis.

Do you have psoriatic arthritis? Share your experience in the comments below, or start a conversation by posting on MyPsoriasisTeam.

Ariel D. Teitel, M.D., M.B.A. is the clinical associate professor of medicine at the NYU Langone Medical Center in New York. Review provided by VeriMed Healthcare Network. Learn more about him here.
Candace Crowley, Ph.D. received her doctorate in immunology from the University of California, Davis, where her thesis focused on immune modulation in childhood asthma. Learn more about her here.

A MyPsoriasisTeam Member said:

This article confused me. I had psoriasis since i was about 6/7, psoriatic arthritis since early teen years (13/14), drs passed off as growing pains. I had no environmental factors, no family history… read more

posted about 2 months ago

hug (3)

Recent articles

Figuring out what to eat when you have psoriasis can feel like solving a riddle. Since there’s no...

Healthy Snacks for Psoriasis: Ideas for Quick and Easy Bites

Figuring out what to eat when you have psoriasis can feel like solving a riddle. Since there’s no...
Figuring out what to eat when you have psoriatic arthritis can feel like trying to solve a...

Snacks for Psoriatic Arthritis: Ideas for Quick and Easy Bites

Figuring out what to eat when you have psoriatic arthritis can feel like trying to solve a...
If you’re living with psoriasis — or you have a loved one with the condition — it’s likely that...

Quiz: Do You Know These Key Facts About Psoriasis?

If you’re living with psoriasis — or you have a loved one with the condition — it’s likely that...
During the COVID-19 pandemic, MyPsoriasisTeam will provide summaries and links to articles of...

COVID-19 and Psoriasis Essential Updates

During the COVID-19 pandemic, MyPsoriasisTeam will provide summaries and links to articles of...
Psoriasis is an autoimmune condition that has no cure, but certain treatments and natural...

Argan Oil for Psoriasis: Can It Help?

Psoriasis is an autoimmune condition that has no cure, but certain treatments and natural...
Living with psoriasis is different for everyone with the condition, but in some cases, it can...

MyPsoriasisTeam Member Portrait: Meet Katya

Living with psoriasis is different for everyone with the condition, but in some cases, it can...
“It used to be that when you had psoriasis, you just learned how to live with the condition. You...

Watch on Demand: Managing and Treating Psoriasis

“It used to be that when you had psoriasis, you just learned how to live with the condition. You...
To sign up for the next live Q&A and watch past Q&A videos, go to (and bookmark)...

MyPsoriasisTeam Live Events Hub

To sign up for the next live Q&A and watch past Q&A videos, go to (and bookmark)...
If you’ve been researching ways to improve your psoriasis or psoriatic arthritis symptoms, you’re...

The Simplicity of the Anti-Inflammatory Diet for Psoriasis and Psoriatic Arthritis

If you’ve been researching ways to improve your psoriasis or psoriatic arthritis symptoms, you’re...
The term “leaky gut syndrome” refers to a condition known as increased intestinal permeability....

Leaky Gut Syndrome and Psoriasis: What’s the Connection?

The term “leaky gut syndrome” refers to a condition known as increased intestinal permeability....
MyPsoriasisTeam My psoriasis Team

Thank you for signing up.

close