Air pollution is already linked to a variety of cardiovascular and respiratory diseases, including heart disease, lung cancer, and asthma. The World Health Organization estimates that air pollution causes 3.7 million premature deaths each year. Recent research by scientists in China, published in the Journal of the American Society of Nephrology, suggests that outdoor pollution in cities can also lead to kidney damage.
Scientists from different universities in China, led by Southern Medical University, collaborated in an 11 year study. They took measurements of the air pollution and collected data from kidney biopsies, controlling for age and region. Over 11 years, they studied a total of 71,151 patients throughout 282 different cities in China.
The researchers found that the chance of developing membranous nephropathy increased by 13% each year during the study period. Membranous nephropathy is a kidney disorder that results in blood vessels becoming thick and inflamed. If untreated, the patient can go into kidney failure. The chance of developing other kidney disorders and diseases remained stable throughout the 11 year period. The highest rates of membranous nephropathy were found in the regions with the highest concentration of fine particulate matter in the air. A person’s chance of developing membranous nephropathy increased in proportion to how much air pollution they were exposed to over time.
Overall, the rate of membranous nephropathy in Chinese cities doubled during the study period. These findings show that air pollution, specifically fine particulate matter, can cause kidney damage. The authors are hopeful that this study will prompt further investigations into how pollution affects the kidneys and other organs. Air pollution is already connected to other health problems, including cardiovascular diseases and strokes. This research highlights the need for reducing air pollution in urban areas and working to identify which organs are most at risk of being damaged.
Fan Fan Hou, MD, PhD and Xin Xu, MD, PhD et al. Long-Term Exposure to Air Pollution and Increased Risk of Membranous Nephropathy in China. Journal of the American Society of Nephrology (2016).