Study of the Impact of Air Pollution on Convulsions in Children: A Hospital-Based Retrospective Study in Hangzhou, China

Background: To investigate the relationship between the occurrence of convulsions in children and air pollution in Hangzhou. Methods: From January 1, 2018, to December 31, 2020, 775 children admitted with convulsion to the pediatric outpatient clinic of The Affiliated Hospital of Hangzhou Normal University (Hangzhou, China) were enrolled in this study. The clinical data and the corresponding weather data of the day in Hangzhou were collected and analyzed. Also, the monthly etiological classification of convulsions and the monthly average air data of Hangzhou were statistically analyzed. Results: The highest incidence of convulsion was observed in children 1 to 2 years old, and higher in boys than in girls. The top three main causes were febrile seizure, benign infantile convulsion with mild gastroenteritis, and epilepsy. Among the meteorological factors, the increase in the level of 2.5 micron particulate matter (PM 2.5 ) in the air per month led to an increase in the number of patients with febrile seizure, benign infantile convulsion with mild gastroenteritis, and epilepsy, where the increase of ozone in 8 hours (O 3 -8h) per month led to a decrease in the number of patients with such conditions. Conclusions: PM 2.5 , PM 10 , and SO 2 are the main meteorological factors affecting the occurrence of convulsions in children in Hangzhou, and PM 2.5 and SO 2 are risk factors. The increase in the level of PM 2.5 in the air per month could increase occurrence of child convulsions, but the increase of O 3 -8h per month could decrease occurrence of child convulsions.