Recurrence of Chronic Urticaria: Incidence and Associated Factors

Background: Chronic urticaria (CU) is urticaria that has been present continuously or intermittently for at least 6 weeks. Although the prevalence and characteristics of CU are well established, little is known about recurrent CU (RCU). Objectives: We sought to establish a definition, determine the frequency, and evaluate risk factors for RCU. Methods: A retrospective chart review of adult patients with CU evaluated at the University of Texas Southwestern allergy and immunology clinic was performed. RCU was defined as CU recurring at least 6 months after cessation of controller therapy and resolution of prior CU symptoms. Charts were reviewed for symptom resolution and recurrence, subtypes of CU (idiopathic, physical, and urticarial vasculitis), and medication usage (first-line agents, alternative agents, and steroid dependence). Results: Forty-five of 341 patients (13%) had RCU. The recurrence group had a higher frequency of alternative agent use at 57.8% (n = 26) compared with the nonrecurrence group at 34.8% (n = 103), which was statistically significant (P <.01). The rate of steroid dependence was similar in both groups (13.3% in the recurrence group vs 14.5%) and not statistically significant. Individuals exposed to anti-inflammatory agents, immunosuppressants, and omalizumab had a significantly higher relative risk of recurrence compared with those who only used first-line agents (relative risk [RR] 2.32, P <.01; RR 2.69, P <.01; and RR 2.18, P =.05, respectively). Conclusions: RCU occurs in approximately 13% of patients with CU in our clinic population. Alternative agent use and antihistamine refractoriness appear to place patients at increased risk for recurrence compared with first-line agent use alone.