<b><i>Background:</i></b> Fine particulate matter (particulate matter with diameter <2.5 µm [PM<sub>2.5</sub>]) is associated with CKD progression and may impact the health of patients living with kidney failure. While older (aged ≥65 years) adults are most vulnerable to the impact of PM<sub>2.5</sub>, it is unclear whether older patients on dialysis are at elevated risk of mortality when exposed to fine particulate matter. <b><i>Methods:</i></b> Older adults initiating dialysis (2010–2016) were identified from US Renal Data System (USRDS). PM<sub>2.5</sub> concentrations were obtained from NASA’s Socioeconomic Data and Application Center (SEDAC) Global Annual PM<sub>2.5</sub> Grids. We investigated the association between PM<sub>2.5</sub> and all-cause mortality using Cox proportional hazard models with linear splines [knot at the current Environmental Protection Agency (EPA) National Ambient Air Quality Standard for PM<sub>2.5</sub> of 12 μg/m<sup>3</sup>] and robust variance. <b><i>Results:</i></b> For older dialysis patients who resided in areas with high PM<sub>2.5</sub>, a 10 μg/m<sup>3</sup> increase in PM<sub>2.5</sub> was associated with 1.16-fold (95% CI: 1.08–1.25) increased risk of mortality; furthermore, those who were female (aHR = 1.26, 95% CI: 1.13–1.42), Black (aHR = 1.31, 95% CI: 1.09–1.59), or had diabetes as a primary cause of kidney failure (aHR = 1.25, 95% CI: 1.13–1.38) were most vulnerable to high PM<sub>2.5</sub>. While the mortality risk associated with PM<sub>2.5</sub> was stronger at higher levels (aHR = 1.19, 95% CI: 1.08–1.32), at lower levels (≤12 μg/m<sup>3</sup>), PM<sub>2.5</sub> was significantly associated with mortality risk (aHR = 1.04, 95% CI: 1.00–1.07) among patients aged ≥75 years (P<sub>slope difference</sub> = 0.006). <b><i>Conclusions:</i></b> Older adults initiating dialysis who resided in ZIP codes with PM<sub>2.5</sub> levels >12 μg/m<sup>3</sup> are at increased risk of mortality. Those aged >75 were at elevated risk even at levels below the EPA Standard for PM<sub>2.5</sub>.
Non-accidental mortality risk of short-term exposure to fine particulate matter and its components in Tokyo
