Psoriatic arthritis is a condition characterized by inflammation in the joints. It occurs in people who have a skin condition called psoriasis, which causes patches of red, scaly, itchy skin.
The symptoms of psoriatic arthritis include joint pain, feelings of stiffness and redness, swelling, and heat in the tissues around the joints. In most cases, the skin symptoms of psoriasis occur before the joint symptoms of psoriatic arthritis.
There is no cure for psoriasis or psoriatic arthritis, but the conditions can be managed.
About 30% of people who have psoriasis develop psoriatic arthritis, and roughly 2.4 million people in the United States have psoriatic arthritis. It’s estimated that around 15% of people with psoriasis may have undiagnosed psoriatic arthritis.
Psoriasis is believed to affect 2% to 3% of the global population—about 125 million people. In the United States, more than eight million people have psoriasis.
Learn more about the data relating to psoriatic arthritis, where it comes from, and what it means.
Who Collects the Data?
The National Psoriasis Foundation collects and shares data on the prevalence of psoriasis and psoriatic arthritis. The data comes from studies published in journals like JAMA Dermatology, Journal of the American Academy of Dermatology, and Journal of Clinical and Aesthetic Dermatology.
One of the most recent studies on the prevalence of psoriasis in adults in the United States was published in JAMA Dermatology in June 2021. The study used data from January 1, 2011, to December 31, 2014, from a sample of a general, non-institutionalized population of U.S. civilians. The participants were aged 20 or older and had an in-person interview followed by a medical exam.
The researchers found that the prevalence of psoriasis among these adults was 3%. The prevalence was similar between men and women. The highest prevalence of psoriasis was among White people; the lowest prevalence was among Black people. The most recent prevalence figures for psoriasis were not notably different from the prevalence recorded in 2003.
What the Data Means
Understanding the prevalence of psoriasis and psoriatic arthritis is necessary to identify the people who are most affected by the condition. The data is also needed to form health policies to address the challenges of the disease.
When Does Psoriatic Arthritis Develop?
Psoriasis and psoriatic arthritis can appear at any age. Psoriasis often has two stages where onset is most common. The first is between the ages of 20 and 30, and the second is between the ages of 50 and 60.
Studies suggest that one in three people with psoriasis have a relative who also had psoriasis. If one parent has psoriasis, their child has a 10% chance of also having psoriasis. If both parents have psoriasis, their child has a 50% chance of having psoriasis.
Roughly 30% of people who have psoriasis also have psoriatic arthritis—that’s roughly 37.5 million people around the world and approximately 2.4 million people in the United States.
Almost 60% of people with psoriasis say that the disease causes them major problems in their daily life. Nearly 40% of people with psoriatic arthritis report feeling the same way about the effects of the condition on their lives.
Research has shown that people with psoriasis are at greater risk of cardiovascular disease, heart attack, metabolic syndrome, depression, and stroke.
A Word From Verywell
Roughly eight million people in the United State have psoriasis, and around 2.4 million of them also have psoriatic arthritis. However, it is believed that more than 15% of people with psoriasis have undiagnosed psoriatic arthritis.
Statistics suggest that psoriasis is less common in Black people than in White people. Specifically, the prevalence of psoriasis is 3.6% in White people and 1.5% in Black people.
However, researchers think that psoriasis is likely under-diagnosed in non-White patients because the clinical presentation of the condition is different in these racial/ethnic groups than it is in White people.
Many people with psoriasis and psoriatic arthritis say that the condition causes them problems in their day-to-day lives. If you have psoriasis and/or psoriatic arthritis, know that even though the conditions are chronic and incurable, there are ways that you can manage them.
If you have psoriasis and think that you might also have psoriatic arthritis, talk to your doctor about your symptoms.
Frequently Asked Questions
What percentage of the population has psoriatic arthritis?
Globally, 2% to 3% of the population has psoriasis—around 125 million people worldwide. About 30% of people who have psoriasis also have psoriatic arthritis (about 37.5 million around the world).
In the United States, more than eight million people have psoriasis, and roughly 2.4 million of those people have psoriatic arthritis.
However, it’s believed that many people with psoriasis have undiagnosed psoriatic arthritis. In the United States, it is estimated that more than 15% of people with psoriasis may have psoriatic arthritis but have not been diagnosed.
That means that there could be up to 1.2 million more people in the United States with psoriatic arthritis than current data indicates, bringing the total closer to 3.6 million people.
What is the life expectancy of someone with psoriatic arthritis?
Psoriatic arthritis is a chronic condition, and there is no cure. While psoriatic arthritis does not specifically lower a person’s life expectancy, some studies have suggested that people with psoriatic arthritis may have a shorter life expectancy than people in the general population because they are at an increased risk of other conditions that do affect life expectancy. These other conditions include diabetes, high blood pressure, lung problems, rheumatoid arthritis, and heart disease.
How many people with psoriasis develop psoriatic arthritis?
About one in three (30%) people with psoriasis will develop psoriatic arthritis. About 85% of people with psoriatic arthritis develop psoriasis first.
Typically, psoriatic arthritis occurs between the ages of 30 and 50, but it can occur at any time.
In many people, psoriatic arthritis develops about 10 years after the onset of psoriasis.
Is psoriatic arthritis a progressive disease?
Psoriatic arthritis can be an unpredictable condition, and the course that the disease takes can be different from one person to the next. In many people with psoriatic arthritis, the condition is progressive—which means that it gets worse over time.
If untreated, psoriatic arthritis can cause deformities and permanent damage to the joints.
Signs that psoriatic arthritis has progressed include:
- More flaresLoss of mobility in the jointsNew bone formationsBone erosionLoss of bone
Not everyone with psoriatic arthritis will experience disease progression. Medications can help reduce symptoms and active disease. Being in remission is when there are no signs of active disease present. For some people with psoriatic arthritis, remission is possible with proper treatment.
However, being in remission does not mean the disease will never return. It is possible that the symptoms will come back and the disease will progress.
