Association between exposure to ambient air pollution and renal function in Korean adults

Background: Ambient air pollution has a negative effect on many diseases, such as cardiovascular and respiratory diseases. Recent studies have reported a relationship between air pollution and renal function, but the results were limited to exposure to particulate matter (PM). This study was to identify associations between various air pollutants and renal function among Korean adults. Methods: Nationwide survey data for a total of 24,407 adults were analyzed. We calculated the estimated glomerular filtration rate (eGFR) for each individual to assess their renal function and used this to categorize those with chronic kidney disease (CKD). To evaluate exposure to ambient air pollution, we used the annual mean concentrations of four ambient air pollutants: PM with an aerodynamic diameter <= 10 mu m (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO). Results: We identified significant inverse relationships between the air pollutants PM10 and NO2 and eGFR in all statistical adjustment models (all p < 0.05). In the full covariate model, interquartile range increases in the annual mean concentrations of PM10 and NO2 were associated with decreases in eGFR levels of 0.46 (95% CI = -0.87, -0.04) and 0. 85 (95% CI = -1.40, -0.30), respectively. Three of the ambient air pollutants were significantly related to an increased risk of CKD in the unadjusted model (p < 0.0001), but all significant associations disappeared after adjusting for covariates (all p> 0.05). Conclusions: Exposures to PM10 and NO2 were significantly associated with decreases in eGFR levels, but not CKD, in Korean adults.