Coagulation and Blood Factors and Clinical Disease Indicators in Patients with Chronic Angioedema and Urticaria—A Validation Study

Background: The interaction between coagulation pathways, inflammatory markers, and hematological parameters has not been sufficiently clarified in patients with chronic angioedema (AE) and urticaria. This study aimed to validate previously observed associations and to further explore their relationship with clinical disease control. Methods: In this cross-sectional validation study, 102 participants were enrolled and stratified into three groups: isolated AE (n = 33), AE associated with urticaria (AE/Urt; n = 34), and healthy controls (n = 35). Serum levels of coagulation factors (D-dimer, fibrinogen, factor VII), inflammatory markers (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR]), and complete blood count parameters were analyzed. Disease control was assessed using the Angioedema Control Test (AECT). Appropriate non-parametric statistical tests were applied. Results: Only D-dimer values differed significantly between groups and were higher in patients with AE/Urt than in controls. At the same time, D-dimers were significantly more often elevated in both AE groups than in healthy individuals. Additionally, CRP values in both AE groups were significantly more often elevated than in controls, with significantly higher values in both AE groups (in both groups 85%) than in controls (57%). Coagulation markers and CRP demonstrated a positive correlation with age (r = 0.268–0.392; p ≤ 0.007), with fibrinogen of all coagulation markers showing the strongest age dependency (r = 0.334; p = 0.001). Gender-related differences in coagulation parameters were not statistically significant, although elevated fibrinogen levels were more common in male participants (p = 0.030). Disease control did not correlate linearly with any inflammatory markers, coagulation factor, age or gender. Conclusions: The findings support a contributory role of coagulation pathway activation and systemic inflammation in the pathophysiology of chronic angioedema and urticaria. These mechanisms may influence clinical disease expression and could represent potential targets for improved diagnostic stratification and therapeutic approaches. However, the interpretation of the present results should be approached with caution in light of several important study limitations, including demographic heterogeneity between the study groups and the relatively limited sample size.