Psoriasis fact file

1. The prevalence of psoriasis is approximately 2-3 % in Sweden.1

The prevalence of psoriasis is approximately 2-3% in the Sweden.1

The condition tends to occur before 35 years of age, although it is not common in children.1

Psoriasis affects men and women equally.2

2. Environmental factors and genetic susceptibility are causes of psoriasis.2

Environmental factors and genetic susceptibility are causes of psoriasis.3
The exact causes of psoriasis are not fully understood; however, studies have shown that certain factors, such as environmental factors and genetic susceptibility, play a role in the development of psoriasis.3

3. Psoriasis is generally characterised by well-delineated red, scaly plaques distributed in a symmetrical pattern.2,4

Presenting symptoms of psoriasis vary among individuals with the condition; however, patients tend to have itchy red skin lesions with well-defined edges and silvery-white scales.4

The plaques can be located on any part of the skin, but are generally found on the scalp, elbows and knees.4

4. Plaque psoriasis is the most common form of the condition, affecting 90% of patients with psoriasis.2

There are a number of different types of psoriasis that are classed according to their appearance:

  • Plaque psoriasis, the most frequently occurring type, is characterised by sharp-edged,round/oval plaques that tend to affect the knees, elbows, torso and scalp3

  • Guttate psoriasis usually presents as widespread small lesions distributed over the torso and limbs, and can be precipitated by streptococcal bacteria3

  • Flexural psoriasis affects body folds and genitals. The lesions tend to be smooth and free of scales and appear as red, shiny, well-defined plaques. The skin can be colonised by Candida yeasts4

  • Pustular psoriasis is a rare type of the disease that is characterised by red inflamed skin that is studded with pustules (pus-filled spots)3

  • Palmoplantar psoriasis generally affects the soles and/or palms3

5. Stress can trigger psoriasis flare-ups.3

Risk factors that have been noted to trigger psoriasis include stress, infection, drug reactions, alcohol consumption, smoking, trauma to the skin and obesity.3,4

6. Patients with psoriasis are at increased risk of developing cardiovascular disease.2

Patients with psoriasis have an increased risk of cardiovascular disease, lymphoma and nonmelanoma skin cancer.2

Patients may have other co-morbidities such as type 2 diabetes, coeliac disease and inflammatory
bowel disease.4

Studies have shown that psoriasis is associated with an increased risk of depression.3

7. Psoriasis can have a major effect on patients’ lives.1b

Psoriasis can have negative effects on patients’ lives, including functional, psychological and social morbidity.2
In addition to symptoms like itching, bleeding and scaling, psoriasis is a visible disease that can be distressing for the patient.2

8. A skin biopsy may be required to support a diagnosis of psoriasis.4

Clinical examination, including a total body evaluation and careful medical history, are often required to diagnose psoriasis. A skin biopsy may also be used for confirmation. Tools such as the Psoriasis Area and Severity Index (PASI) are used to determine the extent and severity of the condition.4 If psoriatic arthritis is suspected, patients may be referred to a rheumatologist for diagnosis and management.

9. Psoriatic arthritis occurs in 30% of patients with moderate-to-severe psoriasis.5

Approximately up to 40% of patients with psoriasis will develop psoriatic arthritis. Patients who develop psoriatic arthritis should be referred to a rheumatologist for specific management of the condition.5