Association between air pollutants and blood cell counts in pediatric patients with asthma: A retrospective observational study

Abstract Background Asthma is a common respiratory disease in children, and air pollution is a risk factor for pediatric asthma. However, how air pollution affects blood cells in pediatric patients with asthma remains unclear. Methods This retrospective observational study, performed in 2007–2018 at a medical center, enrolled non-trauma patients aged 2.5, PM10, sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3) were measured from 11 air-monitoring stations in Kaohsiung City. Results One-unit increases in PM2.5 (regression coefficient = 0.098; S.E. =5.937; p 10 (regression coefficient = 0.129; S.E. =3.541; p 2 (regression coefficient = 0.110; S.E. =15.857; p 2 (regression coefficient = 0.049; S.E. =30.339; p = 0.007), and O3 (regression coefficient = 0.048; S.E. =8.831; p = 0.022) on lag 0–6 (7 d average) correlated positively with ANC. One-unit increases in PM2.5 (regression coefficient = 0.055; S.E. =0.357; p = 0.016), PM10 (regression coefficient = 0.078; S.E. =0.213; p = 0.001), and SO2 (regression coefficient = 0.041; S.E. =1.811; p = 0.024) on lag 0–6 correlated positively with eosinophil count. Additionally, one-unit increases in PM2.5 (regression coefficient = 0.068; S.E. =0.101; p = 0.003) and PM10 (regression coefficient = 0.086; S.E. =0.06; p 2.5 and PMC on ANC and platelet count remained statistically significant after adjusting for other air pollutants. Additionally, PMC correlated significantly with eosinophil count after adjusting for PM2.5, NO2, SO2, and O3. Quartile increases in PM2.5 and PMC levels correlated positively with ANC, eosinophil count, and platelet count, with differences of approximately 13.8% and 16.2%, 18.5% and 17.3%, and 4.4% and 4.6% between the upper and lower quartiles, respectively. Conclusions PM2.5, PMC, and NO2 were independently and positively associated with ANC, PMC was positively associated with eosinophil count, and PM2.5 and PMC were positively associated with platelet count in pediatric patients with asthma. Our results highlight the impact of air pollution on immunity and coagulation in pediatric patients with asthma.