| The type of stroke that results when a
| |
| | stroke, which is caused by bleeding in
|
| blood clot travels to the brain -- called
| |
| | the brain, during the same "high
|
| an ischemic stroke -- is more likely to
| |
| | pollution" days, notes Wellenius, but
|
| occur on days when the air contains a
| |
| | found no association between the
|
| larger concentration of particulate
| |
| | two.Reducing Exposure May Lower RiskThe
|
| matter, according to a study published
| |
| | air pollution in question -- particulate
|
| online in Stroke: Journal of the American
| |
| | matter smaller than 10 micrometers in
|
| Heart Association.Researchers at Beth
| |
| | diameter -- includes particles from car
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| Israel Deaconess Medical Center (BIDMC)
| |
| | and truck exhaust, power plants and
|
| and the Harvard School of Public Health
| |
| | refineries. The measurements were
|
| (HSPH) examined air quality on a total of
| |
| | provided by the US Environmental
|
| 37,000 days in nine cities. Risk of
| |
| | Protection Agency from nine US cities:
|
| hospitalization for ischemic stroke was 1
| |
| | Birmingham, Ala., Chicago, New Haven,
|
| percent higher on days with relatively
| |
| | Conn., Cleveland, Detroit, Minneapolis,
|
| high levels of air pollution, compared
| |
| | Pittsburgh, Salt Lake City and
|
| with low-air pollution days, reports lead
| |
| | Seattle.The authors analyzed hospital
|
| author Gregory Wellenius, ScD,
| |
| | admissions among a group of Medicare
|
| postdoctoral fellow in cardiology at
| |
| | patients with an average age of 79.
|
| BIDMC.Third Cause of Death in US"Although
| |
| | Seventy-five percent of the patients were
|
| these effects sound relatively small,"
| |
| | white, and 61 percent were female. Their
|
| says Wellenius, "given the large number
| |
| | findings showed that during the course of
|
| of people exposed to air pollution and
| |
| | their study, there were 155,503 hospital
|
| the large number of people at risk for
| |
| | admissions for ischemic stroke.The final
|
| stroke ... the actual number of strokes
| |
| | analysis demonstrated a 1.03 percent rise
|
| could be significant."Stroke is the third
| |
| | in ischemic stroke on the days with the
|
| leading cause of death in the US,
| |
| | highest pollution measures."We don't know
|
| affecting more than 700,000 individuals
| |
| | exactly what mechanisms are involved that
|
| each year.A "consistent increased risk"
| |
| | trigger these cardiac events," says
|
| for cardiac health problems associated
| |
| | Wellenius. "However, we do know that
|
| with exposure to ambient air particles
| |
| | particulates in the air promote
|
| was established in earlier research by
| |
| | inflammation, which is a significant risk
|
| Wellenius and coauthors Murray Mittleman,
| |
| | factor for cardiac events; that exposure
|
| MD, DrPH, of BIDMC's Cardiovascular
| |
| | to particulates can lead to changes in
|
| Epidemiology Research Unit and Joel
| |
| | heart rate and blood pressure; and that
|
| Schwartz, PhD, of HSPH."Air pollution has
| |
| | pollution can cause changes in coaguable
|
| been shown to trigger heart attacks and
| |
| | states (related to blood clotting
|
| to aggravate the conditions of patients
| |
| | abilities)."The authors say that future
|
| with congestive heart failure," says
| |
| | research will focus on finding out which
|
| Mittleman, who is also an associate
| |
| | pollutants are most toxic, as well as
|
| professor of medicine at Harvard Medical
| |
| | which patients are at greatest risk for
|
| School."These new findings, demonstrating
| |
| | health problems stemming from air
|
| that incidence of clot-based strokes also
| |
| | pollution."Taken together with previous
|
| increase, [are] in keeping with our
| |
| | work, these latest results support the
|
| earlier data showing a relationship
| |
| | idea that reducing exposure to
|
| between air pollution and heart and lung
| |
| | particulate matter may reduce the risk of
|
| disorders," he notes.The researchers also
| |
| | strokes and heart attacks," they
|
| looked at the incidence of hemorrhagic
| |
| | conclude.
|
