Prognosis of Chronic Spontaneous Urticaria in 117 Patients Not Controlled by a Standard Dose of Antihistamine

Background: Chronic spontaneous urticaria (CSU) is a common skin disorder, but its clinical course reported so far is largely variable, probably due to the heterogeneity of the clinical background of patients and pathogenesis of this disease.

Methods: To reveal the prognosis of refractory CSU, we retrospectively studied the patients who suffered from spontaneous urticaria for six weeks or longer at their first visit to our outpatient clinic, who were insufficiently controlled by a standard dose of antihistamine, and revisited from 2003 to 2009.

Results: Among 223 patients with CSU, 117 patients fulfilled the criteria mentioned above. Mean disease duration at first visit and mean duration of follow-up at our hospital were 27.4 ± 4.2 months and 18.7 ± 1.9 months, respectively. By using Kaplan-Meier methods, the estimated improved rates at 12 months, 24 months, and 60 months were 36.6%, 51.2%, and 66.1%, respectively. The overall improvement rate of childhood cases (<19 years) was significantly higher than that of adult cases (P = 0.007, log-rank test). Moreover, the improvement rate of patients with short disease durations (<1 year at the first visit) was significantly (P = 0.003, log-rank test) higher than that of patients with long disease durations (one year or more).

Conclusion: Our data indicate that the condition of patients with CSU can be gradually improved even in intractable cases. Information about the clinical course and prognostic factors of CSU in this study could help physicians predict the prognosis of patients and ensure medication adherence of patients with CSU.