Chronic kidney disease (CKD) is a worldwide public health problem with a variety of adverse outcomes and heavy health burden. In addition to a dozen well-documented traditional risk factors, several studies recently showed that particulate air pollution may be a novel environmental risk factor of CKD. However, the effects of demographic vulnerabilities and source-specific air pollution exposures on CKD are inconclusive. A recent study by Dr. Chang-Chuan Chan, dean of National Taiwan University College of Public Health, and colleagues examined long-term exposures to particulate matters (PM) in different sizes and traffic-related air pollution in association with a variety of CKD outcomes in Taiwanese elderly. The findings were published in March, 2018 by Environmental Pollution.
This cross-sectional study enrolled 8,497 Taipei City residents older than 65 years from the Taipei City Elderly Health Screening Program in 2009. A variety of pre-clinical to prognostic outcomes, including estimated glomerular filtration rate (eGFR), proteinuria, CKD prevalence, and risk of CKD progression were defined according to KDIGO 2012 guidelines. The participants’ one-year exposures to PM of different sizes, PM2.5 absorbance, nitrogen dioxide (NO2), and nitrogen oxides (NOx) were estimated by land-use regression models, which were developed from the European Study of Cohorts for Air Pollution Effects (ESCAPE) project. One-year exposures to traffic-related air pollutants, including PM2.5 absorbance, NO2 were found to associate with lower eGFR, higher CKD prevalence, and increased risk of CKD progression among the elderly population. The air pollution-related impaired renal function was magnified in non-CKD and non-diabetic subjects.
“Continuing our previous findings on ambient particles in association with CKD among young population, this extended study further suggests that long-term exposure to traffic-related air pollution more adversely affect kidney function in elderly population from preclinical to clinical stage, even the prognosis,” said the first author of this research, Dr. Szu-Ying Chen, who is also the intensivist and adjunct associate professor of E-Da Hospital/I-Shou University.
“Although the risk estimates of CKD regarding the association of air pollution were modest compared to other traditional risk factors, small changes either in the distribution of eGFR levels or CKD prevalence could have a substantial impact on kidney-related illnesses and complications,” concluded Dr. Chan. “Our new findings provide important information in CKD education. Also, it may be helpful to establish more comprehensive air quality control strategies based on the health impact levels of different emission sources.”