The impact of air quality on tissue eosinophilia and the severity of chronic rhinosinusitis phenotypes

Abstract

Background: Particulate matter ≤2.5 µm (PM2.5) exposure exacerbates inflammatory pathways associated with chronic rhinosinusitis (CRS). This study aimed to investigate the impact of PM2.5 exposure on tissue eosinophilia and the severity of CRS. Methodology: One hundred and twenty-nine patients with CRS were enrolled in a cross-sectional study conducted in Thailand and Vietnam. PM2.5 exposure levels in Bangkok, Ho Chi Minh City, and Hue were collected from surface air quality monitoring stations. Presence of CRS with polyps (CRSwNP), eosinophilic CRS (ECRS), tissue eosinophil count (TEC), serum eosinophil count, Visual Analogue Scale (VAS) score, 22-item Sino-Nasal Outcome Test (SNOT-22), rhinologic subscale, endoscopic score (Lund–Kennedy endoscopic score), CT score (Lund–Mackay score), and osteitis score (Kennedy Osteitis score) were assessed. Results: Elevated PM2.5 levels of exposure were independently associated with increased tissue eosinophilia (adjusted prevalence rate ratio (PRR) = 1.015, 95% CI: 1.006–1.024, p = 0.001), higher odds of ECRS (adjusted odds ratio (OR) = 1.020, 95% CI: 1.007–1.034, p = 0.003), CRSwNP (adjusted OR = 1.015, 95% CI: 1.001–1.029, p = 0.035), serum eosinophilia (adjusted mean ratio (MR) = 1.007, 95% CI: 1.003–1.012, p = 0.002), and radiologic severity (adjusted PRR = 1.004, 95% CI: 1.002–1.006, p< 0.001). There were no statistically significant associations withVAS score, SNOT-22 score, rhinologic subscale, endoscopic score, or osteitis. Conclusion: Elevated PM2.5 exposure was independently associated with greater tissue and serum eosinophilia, and CRSwNP phenotype with increased radiologic disease severity. No associations with patient-reported symptom burden or endoscopic severity were demonstrated.