Reviewed by: HU Medical Review Board | Last reviewed: September 2019.
How common is psoriasis?
Although it is difficult to estimate exactly how many people are living with psoriasis, it is thought that the disease affects at least 125 million people around the world. This means that about 2 percent to 3 percent of the global population have some form of psoriasis.1,2
Surveys suggest that around 3 percent of all people over age 20 living in the U.S. have been diagnosed with psoriasis, or 7 million adults.-3
However, researchers think that it is likely that many more than 7 million people in the United States have the disease. This is because many people may not have been diagnosed by a healthcare provider yet, or do not know for sure that they have psoriasis.3
Are some people more likely than others to develop psoriasis?
People of all ages can develop psoriasis. About one-third of people with psoriasis are diagnosed with the disease before the age of 20, and around three-quarters of people are diagnosed before the age of 40. Some people who have never had the condition before will develop it for the first time between the ages of 50 and 60.1,3
Psoriasis affects men and women at equal rates.3
About one-third of people with psoriasis report having a relative with the condition. If a parent has psoriasis, their child has about a 10 percent chance of developing it too. If both parents have psoriasis, their child has about a 50 percent chance of developing the disease.2 Incident rates in children have more than doubled since 1970. Children also are more likely to have serious co-occurring health issues such as depression, anxiety, obesity, diabetes, high blood pressure, high cholesterol, and rheumatoid arthritis.4
Psoriasis can affect people of all ethnicities. In the U.S., research has shown that psoriasis is more common among people of certain ethnicities than others. For example, researchers estimate that in the United States, around 2.5 percent of non-Hispanic Caucasians have psoriasis compared to 1.3% of African Americans. About 80 percent, reported mild disease.1,3
People with psoriasis report more mental distress or mild to severe depression than those without psoriasis. They are also more likely to be obese and be a former smoker.3
What types of psoriasis are the most common?
There are five types of psoriasis:
- Plaque psoriasis is the most common type of the disease.
- Guttate psoriasis is the next most common type, affecting around 10% of people with the disease.2 This type is more common among children and younger adults.
The other three types of psoriasis are much less common, with each affecting around 2 percent to 3 percent of people with psoriasis. Pustular psoriasis, a very severe type, is more common among older people than younger people. Inverse psoriasis tends to affect the skin folds, while psoriatic erythroderma is a very severe form of the disease that affects more than 90% of the body.
Between 10 percent and 30 percent of people with psoriasis will also be diagnosed with a related condition called psoriatic arthritis at some point during their lives.2
What are the financial costs of psoriasis?
Because psoriasis is a condition that affects so many Americans, it has a large financial impact on the economy of the United States. Researchers think that it may cost as much as $135 billion each year.2
Living with psoriasis can also impact a person’s ability to work and earn money. It can cause a person to miss work due to the disease, and it can affect productivity when a person goes to work when they are bothered by their symptoms. One study found that around 20 percent of people with psoriasis missed work due to the disease, while around one-third of people went to work despite feeling unwell due to symptoms related to psoriasis. For example, lesions on the hands may make certain jobs, sports, or caring for others difficult or impossible.5