Psoriasis is a frequent skin disease, which is accompanied by both physical and mental stress. As with other dermatoses, visible physical deficiency can provoke a negative reaction of others, causing a significant psychological burden of disease.
Compared to a set of other chronic diseases, including cancer, myocardial infarction and congestive heart failure, only depression and chronic lung disease psychologically degrade quality of life more than psoriasis. Severe physical stress is not as well understood by scientists, but may be associated with symptoms such as itching or burning.
Symptoms that patients regularly complain about include pain, itching and bleeding. The severity of the disease is also increased by various related diseases such as metabolic syndrome and cardiovascular disease as a result of metabolic syndrome. In 2013, after reviewing a report on the incidence of psoriasis, the Executive Board of WHO recommended 67th session of the World Health Assembly a resolution that requires the Director-General to raise awareness of psoriasis as a major global health problem. The prevalence of psoriasis is also an important factor for WHO. In Europe and North America the prevalence of psoriasis is about 2%.
The prevalence increases approximately linearly throughout life, from 0.12% at age 1 to 1.2% at age 18. About 70-80% of patients have a mild course of psoriasis, which can be controlled only by topical steroids. The prevalence of psoriasis is believed to be influenced by climate, exposure to sunlight, and national origin; however, a recent study found a weak correlation between geographic latitude and psoriasis prevalence, suggesting that other factors, or combinations of factors, may be involved.
Ultraviolet (UV) index is a useful value in the diagnosis and treatment of psoriasis, as the course of skin psoriasis and psoriatic arthritis usually worsens in winter and improves in summer. Patients with psoriasis have an increased risk of developing other serious chronic diseases. These comorbid conditions include psoriatic arthritis, metabolic syndrome or its components, cardiovascular disease, and a variety of other diseases, such as anxiety, depression, non-alcoholic steatogepatosis, Crohn’s disease, and lymphoma.