Predictive value of baseline hematological parameters for the risk of recurrence in chronic urticaria

To investigate the predictive value of baseline hematological parameters for 1year recurrence risk of chronic urticaria (CU) and to construct a clinically practical prediction model.

This retrospective study enrolled 155 newly diagnosed CU patients, with an additional 48 independent patients included for external validation. Baseline clinical characteristics and haematological parameters, including total IgE, C-reactive protein (CRP) and D-dimer (DD), were collected. Univariate and multivariate logistic regression analyses were performed to screen independent influencing factors for recurrence. A nomogram prediction model was subsequently established and comprehensively validated using receiver operating characteristic (ROC) curve, calibration curve, decision curve analysis and SHAP analysis. Kaplan-Meier survival curves and Cox regression analysis were adopted to evaluate recurrence-free survival outcomes.

Among the 155 enrolled patients, 41 developed disease recurrence, corresponding to a recurrence rate of 26.5%. Disease duration (OR = 1.07), total IgE level (OR = 1.01), CRP level (OR = 1.16) and DD level (OR = 1.01) were confirmed as independent predictive factors (all P < 0.05). The combined prediction model achieved an AUC of 0.83 (95% CI: 0.75-0.90), with favorable calibration performance (Hosmer-Lemeshow test, P = 0.446) and stable net clinical benefit within the risk threshold range of 10%-90%. External validation results demonstrated an accuracy of 79.2%, a specificity of 78.4% and a negative predictive value of 93.5%. Patients with disease duration ≥ 20.5 months, total IgE ≥ 173.7 KU/L, CRP ≥ 11.7 mg/L or DD ≥ 142.8 ng/mL had significantly shorter recurrencefree survival time (P < 0.05).

Baseline disease duration, total IgE, CRP and D-D are independent predictors of 1-year recurrence in CU patients. The constructed nomogram model exhibits reliable predictive performance and good clinical applicability, which can serve as a convenient tool for early recurrence risk stratification and individualized clinical management of CU patients.