Short- and medium-term exposure to ambient air pollutants and severity of obstructive sleep apnea: A population-based study in Nanjing.

Short- and medium-term exposure to air pollution and its distinct effects on the severity of obstructive sleep apnea (OSA) remain insufficiently studied. This research investigated the association between short- and medium-term exposure to multiple air pollutants and OSA severity, and identified potential susceptible subgroups. A total of 659 participants diagnosed with OSA were recruited from the affiliated hospital of Nanjing Medical University. OSA severity was measured by the apnea-hypopnea index (AHI) using polysomnography. Air pollution and meteorological data were obtained from the China Meteorological Data Sharing Service System. Multiple linear regression and restricted cubic splines were used to analyze the associations between pollutant exposures and AHI. Subgroup analyses were stratified by age and sex. After adjusting for confounders, short- and medium-term exposure to O3, CO, NO2, and SO2 was significantly associated with increased AHI. Over a 30-day cumulative exposure period, each increment of 10 μg/m3 in O3, 0.1 mg/m3 in CO, 1 μg/m3 in SO2, and 10 μg/m3 in NO2 corresponded to AHI elevations of 2.094, 1.191, 0.504, and 1.225 events/h, respectively. Stratified analyses showed that the effects of these pollutants on AHI were more pronounced in males, while the impacts of O3 and CO were stronger in participants under 65 years of age. In conclusion, short- and medium-term exposure to gaseous pollutants, including O3, CO, NO2, and SO2, is associated with worsened OSA severity. These findings underscore the importance of air quality management for respiratory sleep health and support targeted pollution control strategies, especially for vulnerable groups such as males and younger individuals.