Age, gender, and race differences in nasal morphology: Linking air conditioning and filtration efficiency to disparities in air pollution health outcomes and COVID-19 mortality

Abstract

COVID-19 mortality disparities underscore the critical role of environmental factors, age, sex, and racial demographics. This study investigates how individual variations in nasal morphology – specifically its air conditioning (temperature and humidity regulation) and filtration functions – may influence respiratory health and contribute to differential COVID-19 outcomes.

Analysis reveals significant differences in nasal structure and function across racial, sex, and age groups, demonstrating associations with disparities in respiratory vulnerability to environmental stressors such as air pollution, infectious aerosols, and climatic conditions. Specifically, wider nasal cavities (more common in certain populations), larger male nasal passages, and age-related changes like mucosal atrophy and increased endonasal volume impair air conditioning and filtration efficiency.

These morphological variations influence the nose's protective capacity, which is critical for shielding the middle and lower airways from environmental exposures. Populations with inherently reduced nasal filtration and conditioning efficiency demonstrate higher vulnerability, aligning with U.S. mortality patterns for both COVID-19 and air pollution across demographic groups. This suggests a direct link between nasal anatomy and population-level health disparities.

These findings provide novel insights into the role of nasal anatomy in mediating respiratory health disparities by modulating individual responses to environmental exposures, air pollution, and pathogens. They highlight the need to address critical gaps in understanding how airway characteristics influence susceptibility to environmental stressors and to develop targeted interventions aimed at reducing health disparities.