PM_2.5 and hospitalizations through the emergency department in people with disabilities: a nationwide case-crossover study in South Korea

Background: Little is known about the impact of PM_2.5 on people with disabilities. We aimed to explore the association between PM_2.5 and hospitalization via the emergency department (ED admission) among people with disabilities, together with the attributable ED admission cases and costs. Methods: We applied a time-stratified case-crossover design adjusting ozone, holiday, and temperature using seven years (2015–2021) of claim-based data on ED admissions from the Korean National Health Insurance Database. The analysis included all ED admission cases of beneficiaries with disabilities living in Korea (physical, intellectual, and mental disabilities; brain lesion disorders; blindness or vision loss; deafness or hearing loss; and autism) as well as selected controls without disabilities. Findings: There were 900,311 ED admissions among the 3,624,590 people with disabilities. The odds ratios of ED admissions associated with a 10 μg/m³ increase in PM_2.5 were 1.039 (95% CI: 1.036–1.042) in people with disabilities and 1.022 (95% CI: 1.019–1.025) in people without disabilities. Individuals with mental disability, intellectual disability, and brain lesion disorder showed higher risk estimates compared to other disabilities. The risk estimates of ED admissions for cardiovascular and genitourinary diseases were more prominent among people with disabilities than those without disabilities. Interpretation: The impacts of PM_2.5 on ED admissions was generally higher in the population with disabilities than those without disabilities, especially for certain causes of admission. These results could contribute to establishing targeted action plans including early warning system referring different threshold concentrations. Funding: National Research Foundation.