Epidemiological Investigation of Allergic Rhinitis in Yulin, Northwest China: A Prospective Case-Control Study.

Background Allergic rhinitis (AR), a chronic inflammatory condition of the nasal mucosa mediated by immunoglobulin E (IgE) responses to environmental allergens, represents a significant and escalating global public health challenge. Yulin City ("China's Kuwait") borders the ecologically restored, -dominant Mu Us Desert. An estimated 27% of its population suffers from seasonal AR, yet local epidemiology remains uncharacterized. Objective To elucidate region-specific allergens and risk factors for AR in Yulin's unique semi-arid ecosystem. Methods In this prospective case-control study conducted across 15 municipal hospitals in Yulin, Northwest China, we recruited 300 patients with physician-diagnosed AR and 300 controls without AR from allergy and otolaryngology clinics between August 1, 2023, and July 31, 2024. Cases and controls were matched on age using individual matching (1:1 ratio) with a caliper of ±5 years. Control participants were systematically screened to exclude AR diagnosis through clinical evaluation and symptom assessment. All participants underwent questionnaire surveys and had peripheral venous blood drawn for complete blood count (CBC), C-reactive protein (CRP), and allergen-specific IgE testing. Results This study enrolled 300 AR patients (mean age: 38.17 years; 183 [61.0%] female) and 300 matched controls (mean age: 41.67 years; 194 [64.6%] female). Baseline characteristics, including gender, age, geographic residence, occupation, and prior antibiotic use, demonstrated significant intergroup differences (all <0.01 by chi-square/t-tests). Among AR patients, serum allergen-specific IgE testing identified three predominant allergens: Spreng (181 [60.3%]), common ragweed (70 [23.3%]), and pine (62 [20.7%]). Multivariate logistic regression analysis, adjusted for gender, age, residence, and occupation, revealed antibiotic exposure as an independent risk factor for AR (adjusted odds ratio [aOR]=1.70; 95% confidence interval [CI]: 1.22-2.37; <0.01). This association indicates a 70% increase in the odds of developing AR with antibiotic use. Conclusion The prevention and control of AR in Yulin should focus on managing  Spreng allergens and antibiotic use. These findings provide a scientific basis for optimizing the allocation of regional health resources.