Long-term exposure to ambient particulate matter and kidney function in older adults

Abstract

BackgroundAccumulating studies have linked ambient particulate matter (PM) pollution to impaired kidney function, but the results are still inconsistent and the effect of particulate matter with an aerodynamic diameter ≤1 μm (PM1) on the kidney remains less clear. ObjectiveThis study aimed to investigate the association of long-term exposure to ambient PM1, particulate matter with an aerodynamic diameter ≤2.5 μm (PM2.5), and particulate matter with an aerodynamic diameter ≤10 μm (PM10) with kidney function in older adults. MethodsIn this cross-sectional study, we investigated 199,635 adults who were ≥65 years and underwent physical examinations in 695 community health service centers in Shenzhen, China from 2018 to 2019. An estimated glomerular filtration rate (eGFR) of each subject was derived by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Chronic kidney disease (CKD) was defined as eGFR <60 ml/min/1.73 m2. Proteinuria was assessed by a urine dipstick test on freshly voided urine. A validated 10 km × 10 km grid dataset was used to assess long-term residential exposure to PM1, PM2.5, and PM10 for each subject. Linear regression models and logistic regression models were implemented to quantify the association of exposure to PM with eGFR level, CKD, and proteinuria. ResultsEach 10 μg/m3 increase of exposure to PM1, PM2.5, and PM10 was associated with a 0.9%, 2.7%, and 1.0% decrease in eGFR level, an 18%, 36%, and 17% increase in odds of CKD, and a 15%, 11%, and 10% increase in odds of proteinuria, respectively (all p < 0.05). The associations of exposure to PM with the eGFR level and CKD were stronger among women and subjects who were aged <75 years, never smoked, and never drank alcohol. ConclusionsLong-term exposure to ambient PM1, PM2.5, and PM10 was significantly associated with kidney function impairment in older adults.