Clinical characteristics and treatment response of chronic spontaneous urticaria according to age: A single-center Korean study

BACKGROUND Little information exists regarding the incidence of chronic spontaneous urticaria (CSU) or differences in its characteristics according to age. OBJECTIVE To evaluate the incidence, clinical characteristics and treatment response of CSU according to age. METHODS The relevance of gender, age, history of allergic disease, pre-diagnosis duration, and treatment response were retrospectively evaluated in patients diagnosed with CSU at Pusan National University Hospital between 2011 and 2018. RESULTS A total of 970 patients were included in the study, consisting of 198 children and 772 adults. The CSU incidence increased during the study period in children, but not in adults. CSU was more common in adults than in children and the peak age of occurrence was 20-59 years. Increased female incidence was noted in adults, whereas patient and family allergic history was frequently observed in children than in adults. The overall rate of improvement was remarkably higher in children than in adults (P < 0.01), with pre-diagnosis duration and treatment duration both shorter in children than in adults. (P = 0.001). The proportion of men was higher and treatment duration was shorter in adolescence than in the other age groups, whereas the treatment duration was shorter in patients greater or equal to 60 years than in adults under 60 years, and the step 1 treatment rate was higher. CONCLUSION CSU incidence increased annually in children, but not in adults. The clinical characteristics and treatment response of CSU may differ depending on age and clinicians should be made aware of this fact.