Associations of ambient coarse particulate matter, nitrogen dioxide, and carbon monoxide with the risk of kidney disease: a cohort study

Abstract

Background: Experimental evidence and preliminary clinical evidence suggest that environmental air pollution adversely effects kidney health. Previous work has examined the association between fine particulate matter and risk of kidney disease; however, the association between ambient coarse particulate matter (PM₁₀; ≤10 μm in aerodynamic diameter), nitrogen dioxide (NO₂), and carbon monoxide (CO) and risk of incident chronic kidney disease, chronic kidney disease progression, and end-stage renal disease is not clear.

Methods: We merged multiple large databases, including those of the Environmental Protection Agency and the Department of Veterans Affairs, to build a cohort of US veterans, and used survival models to evaluate the association between PM₁₀, NO₂, and CO concentrations and risk of incident estimated glomerular filtration rate (eGFR) of less than 60 mL/min per 1·73 m², incident chronic kidney disease, eGFR decline of 30% or more, and end-stage renal disease. We treated exposure as time-varying when it was updated annually and as cohort participants moved.

Findings: Between Oct 1, 2003, and Sept 30, 2012, 2 010 398 cohort participants were followed up over a median of 8·52 years (IQR 8·05-8·80). An increased risk of eGFR of less than 60 mL/min per 1·73 m² was associated with an IQR increase in concentrations of PM₁₀ (hazard ratio 1·07, 95% CI 1·06-1·08), NO₂ (1·09, 1·08-1·10), and CO (1·09, 1·08-1·10). An increased risk of incident chronic kidney disease was associated with an IQR increase in concentrations of PM₁₀ (1·07, 1·05-1·08), NO₂ (1·09, 1·08-1·11), and CO (1·10, 1·08-1·11). An increased risk of an eGFR decline of 30% or more was associated with an IQR increase in concentrations of PM₁₀ (1·08, 1·07-1·09), NO₂ (1·12, 1·10-1·13), and CO (1·09, 1·08-1·10). An increased risk of end-stage renal disease was associated with an IQR increase in concentrations of PM₁₀ (1·09, 1·06-1·12), NO₂ (1·09, 1·06-1·12), and CO (1·05, 1·02-1·08). Spline analyses suggested a monotonic increasing association between PM₁₀, NO₂, and CO concentrations and risk of kidney outcomes.

Interpretation: Environmental exposure to higher concentrations of PM₁₀, NO₂, and CO is associated with increased risk of incident chronic kidney disease, eGFR decline, and end-stage renal disease.

Funding: US Department of Veterans Affairs.