Short-term exposure to PM₁₀ and cardiovascular hospitalization in persons with and without disabilities: Invisible population in air pollution epidemiology

Persons with disabilities (PwD), the world's largest minority, can be more susceptible to particulate matter (PM) than persons without disabilities. Although numerous studies have addressed population susceptibility to PM, PwD have not been studied in air pollution epidemiology. This study investigated the association between short-term exposure to PM with an aerodynamic diameter smaller than 10 μm (PM₁₀) and cardiovascular hospital admissions by the existence of a disability, while also considering intersections of disability and other socio-demographic characteristics in South Korea. We used the National Health Insurance Service-National Sample Cohort (NHIS-NSC) to investigate the association between short-term exposure to PM₁₀ and cardiovascular hospital admissions in seven metropolitan cities from 2002 to 2015. We conducted a time-stratified case-crossover analysis using conditional logistic regression and adjusted for daily temperature, relative humidity, air pressure, and national holidays. We conducted stratified analyses according to the existence of a disability, disability type and severity, and socio-demographic characteristics. The results showed that a 10 μg/m³ increase in the 0–3 moving average level of PM₁₀ was associated with 1.9 % (95 % confidence interval [CI]: 0.7 %, 3.2 %) and 0.0 % (95 % CI: −0.5 %, 0.5 %) increase in cardiovascular admissions in persons with and without disabilities, respectively. Among PwD, the associations were pronounced in people with brain lesion disorders (percent change [PC]: 2.7 %, 95 % CI: 0.5 %, 5.0 %), people with visual impairment (PC: 3.0 %, 95 % CI: −1.0 %, 7.1 %), and people with severe disability (PC: 3.0 %, 95 % CI: 0.9 %, 5.0 %). We found that PwD may be more adversely affected by PM₁₀ than their non-disabled counterparts. This suggests that PwD is a social identity reflecting the socially marginalized and disadvantaged population in air pollution epidemiology.