Heterogeneity in clinical appearance of chronic spontaneous urticaria: A cross-sectional analysis of a retrospective cohort

Aim: The study aimed to analyse the characteristics of subtypes of chronic spontaneous urticaria (CSU) and determine the factors that may influence treatment response. Methods: Clinical and laboratory characteristics of CSU patients were compared between 3 groups: (1) those with isolated urticaria (CSUwoAE, n = 50, 27.93%), (2) those with both urticaria and angioedema (CSUwAE, n = 86, 48.04%), and (3) those with isolated angioedema, also referred to as chronic histaminergic angioedema (CHA, n = 43, 24.02%). The Visual Analogue Scale for the worst attack (VAS-WA), Visual Analogue Scale for angioedema control (VAS-AEC), angioedema control test (AECT), Urticaria Control Test (UCT) and Angioedema Quality of Life (AEQoL) were the assessment tools. Results: A weak correlation was observed between disease onset age and BMI (r = 0.295, p < 0.001). The age of onset was higher in CHA than in CSUwAE (p < 0.001). Oropharyngeal angioedema was more frequent in CHA (p = 0.022), whereas eyelid angioedema occurred more often in CSUwAE (p = 0.001). CHA patients had more impaired AEQoL (p = 0.043) and poorer disease control per AECT and VAS-AEC (p < 0.001, p = 0.001, respectively). The rate of high-dose antihistamine response among patients with angioedema was lower in the CHA group (n = 1; 12.5%) compared with the CSUwAE group (n = 10; 66.7%; p = 0.027). Irrespective of CSU subtypes, omalizumab response varied by BMI in patients with angioedema (n = 51; p = 0.002), with the least response in obese patients (p = 0.033). Conclusion: Our study observed that obesity appeared to be associated with a later age of CSU onset and with a lower likelihood of omalizumab responsiveness in patients with angioedema; however, these findings should be interpreted as associations rather than suggesting any causal relationship. Additionally, CHA patients seem to have more severely impaired quality of life and a less controlled disease compared to CSUwAE.