Smog May Induce Heart Attacks
LOS ANGELES (AP) - Smog apparently doesn't hurt just your lungs: New
scientific research suggests that even moderate smog may induce sudden death
in people with existing heart problems.
The newfound evidence, culled from more than a dozen studies on humans and
animals, shows that tiny pieces of soot called particulates may alter the
heart rate in some people, the Los Angeles Times reported Monday.
The link has not yet been proven, but there is a strong likelihood that the
particles cause the heart problems, possibly indicating air pollution poses a
greater public health threat than previously thought, the newspaper said.
Heart disease is the top killer in the United States, responsible for about
half of all deaths.
At smog levels found in many U.S. cities, the inhalation of particulates can
disrupt a person's ability to regulate the pumping of blood. The threat is
particularly severe for older people who have arrhythmia, a condition marked
by an irregular heartbeat.
``When particulate pollution increases, the heart rate seems to go up a
little bit and the variability in the heart rate seems to go down. Those are
things classically seen (in people) with heart failure,'' said Dr. Timothy
Denton, a cardiologist at Cedars-Sinai Medical Center in Los Angeles.
``Studies suggest that people are dying relatively rapidly after you see an
increase in particles. Sometimes it's within 24 hours,'' said Robert Devlin
of the Environmental Protection Agency's clinical research branch.
Changes in heart rhythm that occur after breathing particulates are subtle on
an electrocardiogram and do not affect healthy people.
Arden Pope, an epidemiologist at Brigham Young University, said ``it's
incredibly good news'' if the link can be proven.
``We already know that about half of us die of cardiopulmonary disease, and
if this is true about particulates, we have found a preventable cause,'' Pope
said.
