Natural History of Chronic Urticaria in Korea

Background: Data on the natural history and prognostic variables of chronic urticaria (CU) are rare and information about spontaneous remission of CU is limited. Objective: This study evaluated the natural history of CU and identified predictors for remission. Methods: Total 329 Korean patients with CU, who had follow-ups more than 6 months after diagnosis during a 7-year period in the department of dermatology in three university hospitals were enrolled. Clinical data and laboratory findings obtained by medical records and telephone interviews were analyzed, retrospectively. Results: The proportion recovered in 1, 3, and 5 years after the onset of CU was 10.8%, 18.8%, and 32.9%, respectively. The mean duration of CU was 6.3 years. There were no significant differences in median recovery time depending on sex, age group, severity of CU, and type of CU. The presence of angioedema was significantly related to CU severity. There were no differences in prognosis with respect to the presence of dermographism or angioedema. Patients with atopic dermatitis (AD) had a significantly worse prognosis than patients without a history of AD; but not in patients with the history of allergic rhinitis or asthma. Patients with abnormal laboratory findings did not differ significantly in prognosis. Conclusion: CU remission rate significantly differ according to the presence of AD. This study provides information about the natural course of CU of Korean patients.