Natural history and clinical course of patients with dermographism in a tropical country: a questionnaire-based survey.

Background: Dermographism is the most common form of chronic inducible urticaria. However, the natural history and clinical course of patients with dermographism in tropical countries has not fully been described.

Objective: To examine clinical features, natural history and clinical course of dermographism in Thai patients according to their experiences.

Methods: A cross-sectional, internet-based survey was conducted in 2021. All study respondents completed a 45-item questionnaire that was circulated on social media regarding dermographism.

Results: Among the 2,456 respondents who reported dermographism, 1,900 had symptomatic dermographism (SD), while 556 had simple dermographism (SimD). Of the respondents who reported SD and SimD, the female to male ratio was 2.2:1 and 2.4:1, respectively. The median age of the first episode of SD and SimD was 16 and 15 years, respectively. Older age, greater body weight, cardiovascular diseases, allergic conjunctivitis, atopic dermatitis, changes in temperature, and family history of dermographism were all factors linked to an increased probability of SD. Half of the respondents with SD reported moderate itch severity. Moreover, about half of SD and almost all of SimD respondents let the wheal resolve on its own. Second generation H₁-antihistamines were most commonly prescribed while over-the-counter medicines were taken by both SD and SimD respondents.

Conclusion: This survey highlights several aspects of dermographism in Thai patients which can be useful for healthcare providers. SD is troublesome and affects the quality of life of many patients, leading some to seek medication themselves.