Associations between Long-Term Particulate Matter Exposure and Adult Renal Function in the Taipei Metropolis

Background: Studies on the effect of air pollutions on kidney diseases are still limited.

Objective: We aimed to investigate the associations between particulate matter (PM) exposures and renal function among adults.

Methods: We recruited 21,656 adults as participants from 2007 to 2009. The Taiwanese Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to derive the estimated glomerular filtration rate (eGFR). Subjects with an eGFR lower than 60 mL/min/1.73 m² were defined as having chronic kidney disease (CKD). Land use regression (LUR) models were used to estimate individual exposures to PM with an aerodynamic diameter < 10 μm (PM₁₀), coarse particles (PM_Coarse), fine particles (PM_2.5), and PM_{2.5Absorbance}. Generalized linear and logistic regression models were used to estimate the associations between PM exposure and renal function.

Results: An IQR increase in PM₁₀ (5.83 μg/m³) was negatively associated with eGFR by -0.69 (95% CI: -0.89, -0.48) mL/min/1.73 m² and positively associated with the prevalence of CKD with adjusted OR = 1.15 (95% CI: 1.07, 1.23). An IQR increase in PM_Coarse (6.59 μg/m³) was significantly associated with lower eGFR by -1.07 (95% CI: -1.32, -0.81) mL/min/1.73 m² and CKD with OR = 1.26 (95% CI: 1.15, 1.38). In contrast, neither outcome was significantly associated with PM_2.5 or PM_{2.5Absorbance}. Stratified analyses indicated that associations of CKD with both PM₁₀ and PM_Coarse were limited to participants < 65 years of age, and were stronger (for PM₁₀) or limited to (PM_Coarse) women. Associations also appeared to be stronger in those without (vs. with) hypertension, and in normal versus overweight participants.

Conclusions: Exposure during the previous year to PM₁₀ and PM_Coarse, but not PM_2.5 or PM_{2.5Absorbance}, was associated with reduced renal function among Taiwanese adults.