Supplementary Material for: Risk Factors for Severe Allergic Rhinitis and the Association with Serum sIgE Levels: A Study in Guangzhou, China

Background: The control of risk factors is crucial for the management of allergic rhinitis (AR), and it contributes to reduce both direct medical costs and indirect economic burdens. The research on risk factors for severe AR and the association between serum allergen-specific immunoglobulin E (sIgE) and the severity of AR is currently limited and inconsistent.
Methods: The study utilized data from a cross-sectional epidemiological survey conducted in Guangzhou, China, from April 2023 to March 2024, involved 638 AR patients. We used Visual Analogue Scale (VAS) scores to assess the severity of AR. Data of daily risk factors were collected through face-to-face questionnaires, and serum sIgE levels were measured using the AllergyScreen assay (Mediwiss-Analytic GmbH, Moers, Germany). A generalized linear model was used to investigate the associations.
Results: Our findings indicate that patients with severe AR exhibited more unhealthy lifestyle habits and lived in high-risk environments compared to non-severe patients. Physical activity more than three times per week was associated with a reduced risk of severe symptoms (OR: 0.55, 95% CI: 0.36, 0.82). Frequent indoor cleaning also lowered the risk of severe AR (OR: 0.70, 95% CI: 0.56, 0.87). Additionally, a one-level increase in serum sIgE was linked to higher odds of severe AR (OR: 1.26, 95% CI: 1.11, 1.43) after adjusting for risk factors.
Conclusion: Severe AR is associated with poor household cleaning and less exercise. Higher serum sIgE levels correspond to a higher risk of severe AR