๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
EPIDEMIOLOGY
Depending on the age range and method of sampling, estimates of the lifetime prevalence of acute and chronic urticaria in the general population range from 8% to 22%. In a recent meta-analysis, chronic urticaria had overall lifetime and point prevalence rates of 1.4% and 0.7%, respectively. The prevalence of specific subtypes of chronic urticaria, e.g. the inducible urticarias, is lower.
Urticaria is a worldwide disease and may present at any age, with the peak incidence dependent upon etiology. The proportion of cases due to different etiologic agents is likely related to the frequency of environmental exposures, such as infections and allergens, in different countries, but estimates of this are not available. It is also often difficult to prove a cause and effect, and so an underlying condition may be inappropriately โblamedโ for causing urticaria. Overall, urticaria is more common in women, with a femaleโ:โmale ratio of ~2โ:โ1 for CSU, but the ratio varies with the different physical urticarias. For example, women outnumber men in dermographism and cold urticaria, but more men develop delayed pressure urticaria. Hereditary angioedema has an autosomal dominant inheritance pattern and occurs in ~1 in 50โ000 individuals, with a range that varies from 1 in 20โ000 to 1 in 60โ000.