Featured Research

from universities, journals, and other organizations

Short-term exposure to most major air pollutants associated with increased risk of heart attack

Date:
February 14, 2012
Source:
JAMA and Archives Journals
Summary:
Short-term exposure (for up to 7 days) to all major air pollutants, with the exception of ozone, is significantly associated with an increased risk of heart attack, according to a new review article.

Short-term exposure (for up to 7 days) to all major air pollutants, with the exception of ozone, is significantly associated with an increased risk of heart attack, according to a review and meta-analysis of previous studies appearing in the February 15 issue of JAMA.

Related Articles


The potentially harmful effect of episodes of high air pollution on health has been suspected for more than 50 years. "In industrialized countries, cardiovascular disease is the leading cause of mortality and is associated with significant morbidity. These countries have high pollution levels. Since the 1990s, many epidemiological studies have demonstrated associations between air pollution levels and human health in terms of hospital admissions and overall mortality, including respiratory or cardiovascular mortality. However, the association between air pollution and near-term risk of myocardial infarction [MI; heart attack] remains controversial. Some studies have shown an association, while other studies have found either no association or association only for selected pollutants," according to background information in the article.

Hazrije Mustafic, M.D., M.P.H., of the University Paris Descartes, INSERM Unit 970, Paris, and colleagues conducted a systematic review and meta-analysis to examine the association between short-term exposure to air pollutants and the risk of heart attack, and to quantify these associations. The major air pollutants included in the analysis were ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter (PM) with an aerodynamic diameter of 10 μm (micrometers; PM10) or less and those 2.5 micrometers (PM2.5) or less.

The researchers conducted a search of the medical literature and identified 34 studies that met criteria for inclusion in the analysis, which indicated associations of statistical significance between all analyzed air pollutants and heart attack risk, with the exception of ozone. The subgroup analysis, based on study quality, yielded results comparable with those from the overall analysis.

The authors suggest a number of possible mechanisms for the associations found. "The first potential mechanism is inflammation. Studies have shown that levels of inflammatory markers such as C-reactive protein are higher as a result of exposure to air pollution. The second potential mechanism is abnormal regulation of the cardiac autonomic system. Several observational studies have linked high levels of air pollution with increased heart rate and decreased heart rate variability. The third possible mechanism is an increase in blood viscosity as a result of air pollution. This association can promote thrombus [blood clot] formation, accelerate the progression of atherosclerosis, and weaken the stability of atherosclerotic plaques."

The researchers acknowledge that the magnitude of association found in this study is relatively small compared with those of classic heart attack risk factors, such as smoking, hypertension, or diabetes. "Nevertheless, the population attributable fractions of each pollutant is not negligible because the majority of the population, including young and disabled patients, is exposed to air pollution, particularly in urban settings, and thus an improvement in air quality could have a significant effect on public health."

"In conclusion, our meta-analysis is the first to our knowledge to evaluate the quality and magnitude of associations between short-term exposure to major air pollutants and the risk of MI," the authors write. "Further research is needed to determine whether effective interventions that improve air quality are associated with a decreased incidence of MI."


Story Source:

The above story is based on materials provided by JAMA and Archives Journals. Note: Materials may be edited for content and length.


Journal Reference:

  1. H. Mustafic, P. Jabre, C. Caussin, M. H. Murad, S. Escolano, M. Tafflet, M.-C. Perier, E. Marijon, D. Vernerey, J.-P. Empana, X. Jouven. Main Air Pollutants and Myocardial Infarction: A Systematic Review and Meta-analysis. JAMA: The Journal of the American Medical Association, 2012; 307 (7): 713 DOI: 10.1001/jama.2012.126

Cite This Page:

JAMA and Archives Journals. "Short-term exposure to most major air pollutants associated with increased risk of heart attack." ScienceDaily. ScienceDaily, 14 February 2012. <www.sciencedaily.com/releases/2012/02/120214171040.htm>.
JAMA and Archives Journals. (2012, February 14). Short-term exposure to most major air pollutants associated with increased risk of heart attack. ScienceDaily. Retrieved February 28, 2015 from www.sciencedaily.com/releases/2012/02/120214171040.htm
JAMA and Archives Journals. "Short-term exposure to most major air pollutants associated with increased risk of heart attack." ScienceDaily. www.sciencedaily.com/releases/2012/02/120214171040.htm (accessed February 28, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Saturday, February 28, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Whale-Watching Scientists Spot Baby Orca

Whale-Watching Scientists Spot Baby Orca

AP (Feb. 28, 2015) Researchers following endangered killer whales spotted a baby orca off the coast of Washington state, the third birth documented this winter but still leaving the population dangerously low. (Feb. 28) Video provided by AP
Powered by NewsLook.com
Bridge Collapses Due to Flooding in Bolivia

Bridge Collapses Due to Flooding in Bolivia

Reuters - News Video Online (Feb. 28, 2015) Heavy rain and flooding sweep through parts of Bolivia causing damage and leaves more than 2,000 people homeless. Sophia Soo reports. Video provided by Reuters
Powered by NewsLook.com
Death Toll from Afghan Avalanches Tops 200

Death Toll from Afghan Avalanches Tops 200

AFP (Feb. 27, 2015) More than 200 people have been killed in a series of avalanches triggered by heavy snowfall in Afghanistan. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
France, Philippines Call for Agreement on Climate Change

France, Philippines Call for Agreement on Climate Change

Reuters - News Video Online (Feb. 27, 2015) The presidents of France and the Philippines issue a joint appeal for a binding agreement on climate change. Katie Sargent reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins