Air Pollution Is Associated With Increased Sinus Tissue Eosinophilia In Chronic Rhinosinusitis

Abstract

Racial and ethnic minorities living in neighborhoods with lower socioeconomic status (SES) are at risk for poor CRS outcomes. While low SES is linked to poor health care access, residents of low-income neighborhoods are also exposed to higher pollution. This study aimed to assess the relationship of multiple pollution-related indices to sinonasal histopathology in CRS patients. In this cross-sectional study, sinus tissue was collected from the ethmoid or maxillary sinus during functional endoscopic sinus surgery. Samples were examined for multiple histopathologic markers associated with CRS including eosinophilic and neutrophilic infiltration, fibrosis, decreased glands and basement thickening. The primary exposure variable was ambient particulate matter <2.5 μm in size (PM2.5). The secondary exposure variables were earth level ozone and distance from major roads. Pollution indices were obtained using Environmental Protection Agency data for each individual’s address at the block-group level. Regression analyses and analysis of variance were performed to investigate the association of pollution with histopathology markers. Seventy-eight patients with CRS were included. PM2.5 levels in air (μg/m3) were significantly higher for patients with eosinophil aggregates in the sinus tissue (PM2.5 (mean±SD) was 11.46±0.18 for those with eosinophilic aggregates vs. 11.03±0.54 in cases without eosinophilic aggregates; p=0.013). Earth level ozone and distance from major roads were not associated with any of the histopathology variables. Air pollution, specifically PM2.5, influences eosinophilic infiltration in the sinonasal tissue. Larger studies are needed to validate this association and, the possible mechanism linking pollution to Th-2 inflammation in CRS.