DOI: https://doi.org/10.21203/rs.3.rs-1168107/v1
Objective: There is limited evidence concerning the association between air pollution and outpatient visits in moderately polluted areas. This paper investigates the effects of moderate level ambient air pollution on the number of outpatient visits associated with five categories of medical conditions.
Methods: We analyzed a total of 1,340,791 outpatient visits for five medical departments (pediatrics, respiratory, ENT, cardiovascular, and orthopedics) in Xiβan from 2016 to 2018. A distributed non-linear model was used to analyze the associations and was fitted and stratified by age and season.
Results: We found ππ2 had the largest effect on pediatrics visits (RR=1.105 (1.090, 1.121)). The relationships among ππ2.5 and π3 and ENT were more statistically significant in a heating season than those in a non-heating season. Meanwhile, ππ2.5, ππ10, and ππ2 had bigger impacts on ENT visits for people under 50 years. The results showed a strong association between π3 and cardiovascular outpatient visits in a non-heating season (RR=1.026 (1.020,1.032)). The results also showed that ππ10 was not significantly associated with respiratory outpatient visits, and every 10 ππ/π3 increase of ππ2 reduced the number of respiratory outpatient visits by 3%. We found ππ2.5 and ππ2 were significantly related to orthopedic outpatient visits for people under 60.
Conclusion: Our findings indicated short-term exposure to air pollutants had varying associations with outpatient visits to four medical departments. We also proposed a new set of air pollution thresholds, which could help hospitals optimize outpatient resource allocation and the government determine appropriate air quality standards.