Inflammatory Shift in Chronic Rhinosinusitis Amidst Guangzhou's Urbanization (2000–2018)

ABSTRACT Background Chronic rhinosinusitis (CRS) exhibits temporal and geographic diversity in pathological endotypes with progressive eosinophilic infiltration, while the underlying causes remain unclear. Current pathological endotypes determination relies on mean cell count per high‐power field, requiring accuracy optimization. Methods In this retrospective study, 970 CRS patients in Guangzhou from 2000 to 2018 undergoing endoscopic sinus surgery were divided into five biennial cohorts. Demographic, clinical, and pathological data were analyzed to compare subgroup differences and assess correlations between pathological features and urbanization indicators, including land use, socioeconomic status, and motor vehicle ownership. Pathological outcomes were assessed via artificial intelligence‑based whole‐slide imaging. Results Allergic comorbidity of CRS patients increased from 5.38% to 15.36% ( p < 0.05). Pathological eosinophil density surged from 7.58 to 265.98 counts/mm², with eosinophilic CRS prevalence rising from 10.75% to 40.85%. Urbanization indicators were strongly associated with overall inflammation and eosinophilia, underscoring urbanization's role in CRS inflammatory progression. Motor vehicle ownership ( R ² = 0.91, p < 0.01) and population density ( R ² = 0.90, p < 0.01) ranked as the top two correlates of eosinophil density. Furthermore, population density ( R ² = 0.94, p < 0.01) and per capita gross regional product ( R ² = 0.92, p < 0.01) ranked as the top two correlates of total inflammation cell density. Conclusions Among CRS patients in Guangzhou, pathological overall inflammation and eosinophilic infiltration progressively increased, while the proportion of lymphocytes declined. Additionally, urbanization indicators, notably population density, were strongly associated with shifts in the inflammatory profile and the rising prevalence of allergic comorbidities.