Can the length of strands of DNA in patients with
heart disease predict their life expectancy?
Researchers from the Intermountain Heart Institute
at Intermountain Medical Center in Salt Lake City,
who studied the DNA of more that 3,500 patients with
heart disease, say yes it can.
In the new study, presented Saturday, March 9 at the
American College of Cardiology’s Annual Scientific
Session in San Francisco, the researchers were able
to predict survival rates among patients with heart
disease based on the length of strands of DNA found
on the ends of chromosomes known as telomeres—the
longer the patient’s telomeres, the greater the
chance of living a longer life.
The study is one of 17 studies from the
Intermountain Heart Institute at Intermountain
Medical Center that are being presented at the
scientific session, which is being attended by
thousands of cardiologists and heart experts from
around the world.
Previous research has shown that telomere length can
be used as a measure of age, but these expanded
findings suggest that telomere length may also
predict the life expectancy of patients with heart
disease.
Telomeres protect the ends of chromosome from
becoming damaged. As people get older, their
telomeres get shorter until the cell is no longer
able to divide.
Shortened telomeres are associated with age-related
diseases such as heart disease or cancer, as well as
exposure to oxidative damage from stress, smoking,
air pollution, or conditions that accelerate
biologic aging.
“Chromosomes by their nature get shorter as we get
older,” said John Carlquist, PhD, director of the
Intermountain Heart Institute Genetics Lab. “Once
they become too short, they no longer function
properly, signaling the end of life for the cell.
And when cells reach this stage, the patient’s risk
for age-associated diseases increases dramatically.”
Dr. Carlquist and his colleagues from the
Intermountain Heart Institute at Intermountain
Medical Center tested the DNA samples from more than
3,500 heart attack and stroke patients.
“Our research shows that if we statistically adjust
for age, patients with longer telomeres live longer,
suggesting that telomere length is more than just a
measure of age, but may also indicate the
probability for survival. Longer telomere length
directly correlate with the likelihood for a longer
life—even for patients with heart disease,” said Dr.
Carlquist.
Dr. Carlquist and his colleagues from the
Intermountain Heart Institute at Intermountain
Medical Center drew on two unique resources that
offer unparalleled opportunity for researchers to
study the effects of telomere length and survival
rates of heart patients:
An archive of peripheral blood DNA samples collected
from almost 30,000 heart patients, with as much as
20 years of follow-up clinical and survival data.
This is stored in Intermountain Healthcare’s
world-renowned computerized medical informatics
record system.
“With so many samples and very complete electronic
records, it’s a unique resource,” said Dr. Carlquist.
“It’s unmatched in the world, and it allows us to
measure the rate of change in the length of a
patient’s telomeres over time rather than just a
snapshot in time, which is typical for most studies.”
The opportunity to work with experts from around the
world, including Richard Cawthon, MD, PhD, who’s an
international expert on telomere measurement and
function.
“I believe telomere length could be used in the
future as a way to measure the effectiveness of
heart care treatment,” said Dr. Carlquist. “We can
already test cholesterol and blood pressure of a
patient to see how treatment is working, but this
could give us a deeper view into how the treatment
is affecting the body and whether or not the
treatment is working.”
Other members of the research team include: Stacey
Knight, PhD; Benjamin Horne, PhD; Jeffrey Rollo, BS;
John Huntinghouse, BS; Brent Muhlestein, MD; and
Jeffrey Anderson, MD.
The Intermountain Medical Center Heart Institute at
Intermountain Medical Center in Murray, Utah, is one
of the premier cardiac centers in the country, and
serves as the flagship center for the Intermountain
Healthcare system, based in Salt Lake City.
See also
Offspring of older fathers may live longer
(23/07/2012)
Ultra short telomeres linked to osteoarthritis
(24/01/2012)
For more information
Intermountain Healthcare
(MDN)
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