Chronic Spontaneous Urticaria Combined Atopic Dermatitis/Other Atopic Comorbidities: Clinical Characteristics, Therapeutic Response to Omalizumab, and Drug Survival.

BACKGROUND

Atopic comorbidities are common in chronic spontaneous urticaria (CSU), yet their impact on clinical presentation and omalizumab response remains poorly defined.

OBJECTIVE

To compare clinical profiles and omalizumab treatment outcomes in CSU patients with atopic dermatitis (AD) and other atopic comorbidities (OACs).

METHODS

This single-center retrospective study included 381 CSU patients treated with ≥3 doses of omalizumab (300 mg/4 weeks) and followed ≥6 months (January 2023-March 2025). Based on the presence or history of atopic comorbidities, patients were stratified into 3 groups: CSU with AD (CSU-AD, n = 76), CSU with OACs (CSU-OACs, n = 93), and CSU with no atopic comorbidities (CSU-NA, n = 212). Clinical features, treatment response (efficacy, speed, and adverse events), and-among 12-month completers-dose reduction/discontinuation and drug survival rates were analyzed.

RESULTS

Of all enrolled patients, 44.4% had comorbid allergic diseases. CSU-OACs patients had earlier onset (P = 0.033) and higher angioedema prevalence (P = 0.042); CSU-AD showed higher baseline UAS7 (P = 0.031). Overall omalizumab response rates did not differ significantly among the 3 groups (P = 0.115), but a significantly higher portion of faster-response speed was observed in CSU-OAC (P = 0.019). Adverse events were significantly higher in CSU-OACs (P = 0.004), especially injection-site reactions (P = 0.033) and systemic effects (eg, headache and fatigue; P = 0.025). Drug survival was significantly higher in the CSU-OAC vs. CSU-NA group (P = 0.007).

CONCLUSION

CSU-AD differs only in higher baseline activity, otherwise resembling CSU-NA in treatment response and drug survival. CSU-OACs exhibit not only distinct features such as earlier onset, higher angioedema risk, faster response, and higher drug survival but also more adverse events, indicating that CSU-OAC requires individualized management. Larger multicenter studies are needed to further define the impact of AD and OACs in CSU.