Soot?s Impact on Heart Comparable to Risk for Former Smokers
In a follow-up analysis to the American Cancer Society cohort study, researchers have reported a striking link between chronic exposure to fine particle air pollution and increased risk of death from cardiovascular disease in the United States.
The increased risk was comparable to that associated with being a former smoker. The new analysis is based on data collected by the American Cancer Society on the cause of death of 500,000 adults over a 16-year period, and on data on air pollution levels in cities nationwide. Data on other risk factors such as body mass, smoking, occupational exposures, and diet were also considered.
The study identifies a strong link between particulate air pollution and ischemic heart disease (which causes heart attacks), and also a link between pollution and irregular heart rhythms, heart failure, and cardiac arrest. It also suggests general biological pathways through which pollution might cause these diseases that lead to death — increased inflammation and nervous system aberrations that change heart rhythm. Mortality attributable to respiratory disease had relatively weak associations in this study.
Researchers conclude that “the results of this analysis are largely consistent with the proposition that the general pathophysiological pathways that link long-term PM exposure and cardiopulmonary mortality risk include pulmonary and systemic inflammation, accelerated atherosclerosis, and altered cardiac autonomic function.”
Pope, C.A. III, Burnett, R.T., Thurston, G.D., Thun, M.J., Calle, E.E., Krewski, D., and Godleski, J.J. Cardiovascular Mortality and Long-Term Exposure to Particulate Air Pollution: Epidemiological Evidence of General Pathophysiological Pathways of Disease. Circulation. 2004;109:71-77
The American Heart Association [www.circ.ahajournals.org/] offers the abstract online.
