Particulate matter air pollution and cardiovascular disease: An update to the scientific statement from the American Heart Association
In 2004, the first American Heart Association scientific statement on “Air Pollution and Cardiovascular; Disease” concluded that exposure to particulate matter (PM) air pollution contributes to cardiovascular morbidity and; mortality. In the interim, numerous studies have expanded our understanding of this association and further elucidated; the physiological and molecular mechanisms involved. The main objective of this updated American Heart Association; scientific statement is to provide a comprehensive review of the new evidence linking PM exposure with cardiovascular; disease, with a specific focus on highlighting the clinical implications for researchers and healthcare providers. The; writing group also sought to provide expert consensus opinions on many aspects of the current state of science and; updated suggestions for areas of future research. On the basis of the findings of this review, several new conclusions; were reached, including the following: Exposure to PM ?2.5; m in diameter (PM2.5) over a few hours to weeks can; trigger cardiovascular disease–related mortality and nonfatal events; longer-term exposure (eg, a few years) increases; the risk for cardiovascular mortality to an even greater extent than exposures over a few days and reduces life expectancy; within more highly exposed segments of the population by several months to a few years; reductions in PM levels are; associated with decreases in cardiovascular mortality within a time frame as short as a few years; and many credible; pathological mechanisms have been elucidated that lend biological plausibility to these findings. It is the opinion of the; writing group that the overall evidence is consistent with a causal relationship between PM2.5 exposure and; cardiovascular morbidity and mortality. This body of evidence has grown and been strengthened substantially since the; first American Heart Association scientific statement was published. Finally, PM2.5 exposure is deemed a modifiable; factor that contributes to cardiovascular morbidity and mortality.