Running in Polluted Air Is a Two-edged Sword

Physical Exercise in Low Air Pollution Areas Is Cardioprotective But Detrimental for the Heart in High Air Pollution Areas

Thomas Münzel; Omar Hahad; Andreas Daiber


Eur Heart J. 2021;42(25):2498-2500. 

In This Article

Air Pollution as a Cardiovascular Risk Factor

In 2015, the Lancet Commission on Pollution and Health concluded that 'Pollution is the largest environmental cause of disease and premature death in the world today. Diseases caused by pollution were responsible for an estimated 9 million premature deaths in 2015—16% of all deaths worldwide'.[1] Also the World Health Organization (WHO) calculates that 12.6 million premature deaths per year are attributable to an unhealthy environment, 8.2 million of which are due to non-communicable diseases, with cardiovascular disease (CVD) (including stroke) being the largest contributor, accounting for nearly 5 million of these deaths.[2] Among all environmental pollutants, air pollution is the most important risk factor, and ambient outdoor air pollution due to particulate matter <2.5 μm (PM2.5) exposure ranked fifth among all global risk factors in 2015, leading to 4.2 million deaths annually as estimated by the Global Burden of Diseases (GBD) study.[3] Nine out of 10 people worldwide are exposed to ambient air pollutant levels above WHO guidelines (>10 μg/m3). Using a novel exposure response hazard function [global estimate of exposure mortality model (GEMM)], the mortality attributable to air pollution was estimated to be 9 million premature deaths at the global level[4] and 790 000 excess deaths in Europe alone.[5] These figures are also in line with the substantial impact of air pollution on cardiovascular morbidity and mortality as reported by a position paper by the American Heart Association.[6] Mounting evidence suggests that health risks attributable to PM2.5 persist even at low levels, below WHO air quality guidelines and European standards (annual levels <10 and <25 μg/m3, respectively).