Prognostic Factors for Chronic Spontaneous Urticaria: A 6-Month Prospective Observational Study

Abstract

PURPOSE: Chronic urticaria (CU) has a substantial impact on the quality of life. Little clinical data on the prognosis of CU has been reported. This study aimed to investigate the control status and remission rate of CU and to explore potential predictors of good responses to the treatment during a 6-month treatment period. METHODS: A total of 75 patients with chronic spontaneous urticaria (CSU) were enrolled from 3 university hospitals in Korea. Urticaria control state was classified into 2 groups: group I (remission and well-controlled) and group II (partly and uncontrolled). CU-specific quality of life (CU-QoL) and the urticaria activity score (UAS) were measured before and after the treatment. Autologous serum skin test (ASST), and anti-nuclear and anti-thyroid antibodies were measured at the enrollment into the study. Aspirin intolerance was confirmed by an oral provocation test. RESULTS: Of 59 patients completing the study, 21 (35.6%) arrived at well-controlled status and only 2 (3.4%) achieved remission, whereas 26 (44.1%) remained at partly controlled status and 10 (16.9%) were at uncontrolled status. Mean changes in CU-QoL (36.5+/-2.7 vs 20.6+/-4.3, P=0.017) and UAS (-7.9+/-0.8 vs -3.0+/-1.0, P=0.001) were significantly different between groups I and II. The presence of serum autoantibodies and aspirin intolerance had no influence on the control of urticaria in this study. However, ASST positivity was identified as a significant predictor of CU control in multivariate analysis (OR=6.106, P=0.017). CONCLUSIONS: The proportion of CSU patients that achieved remission or a well-controlled state was 39% for the 6 months of stepwise treatment. Longer observations are necessary to assess the exact prognosis of CSU. ASST results may be a useful parameter for predicting a better response to treatment and both UAS and CU-QoL are helpful to monitor therapeutic response.