Short-term effects of air pollutants on hospitalization for childhood respiratory diseases in Suzhou City: a time-stratified case-crossover study.

Background: Short-term exposure to air pollution has been demonstrated in previous studies to correlate with respiratory disease (RD) in children. Due to regional heterogeneity, our objective was to explore the correlation between short-term exposure to ambient air pollution and hospital admissions for respiratory ailments in children in Suzhou City from January 1, 2017, to December 31, 2022, alongside assessing the influence of the COVID-19 pandemic on this relationship.

Methods: We collected data on air pollutant levels and hospital admissions for childhood respiratory disease (RD) in Suzhou, China, from 2017 to 2022. We utilized a time-stratified case-crossover design along with a conditional logistic regression model to assess the short-term impacts of air pollutants on RD in children through stratified analysis and sensitivity analysis.

Results: A total of 13,408 children with respiratory diseases were included in the study. The findings revealed significant associations between hospitalization for respiratory diseases in children and exposure to PM_2.5, PM₁₀, SO₂, NO₂, and CO. The maximum effect values (95%CI, best lag days) for each 10 µg/m³ increase in the concentrations of PM_2.5, PM₁₀, SO₂, and NO₂ were as follows: 1.017 (1.003-1.031, lag0-2), 1.015 (1.004-1.026, lag0-2), 1.117 (1.001-1.247, lag0-1), and 1.036 (1.009-1.064, lag0-7). Additionally, the maximum effect value (95%CI, best lag days) for each 1 mg/m³ increase in CO concentration was found to be 1.267 1.017-1.579, lag0-7). Stratified analysis indicated that sex, season of admission, and stage of admission did not modify these correlations significantly; however, differential effects on various age groups and sexes were primarily observed among school-age and older children as well as boys.

Conclusions: The short-term exposure to PM_2.5, PM₁₀, SO₂, NO₂, and CO in Suzhou, China, exhibited a positive correlation with RD hospitalization. Prior to the COVID-19 pandemic, the adverse impacts of air pollutants on hospitalizations for childhood respiratory disease were mitigated compared to the period following the pandemic. Local governments should continue promoting decisions and measures for air pollution prevention and control to reduce further pollutant concentration, which is crucial for public health in reducing the burden of childhood respiratory diseases.