Diet, exercise slow rising blood
sugar levels
February 15, 2005
By David Wahlberg
Richard Mehlan knew he was at risk for diabetes. He
is overweight, he has high blood fat levels, and his
mother had the disease.
But until last month, the 57-year-old from Marietta
didn't know he had "pre-diabetes." The term,
recently coined by health officials, indicates a partly
elevated blood sugar level that will likely develop
into full diabetes within 10 years if nothing is done
to stop it.
Scientists now have proof that something can: a healthy
diet and exercise.
Doctors have known for years that type 2, or adult-onset,
diabetes usually comes on gradually, often as people
gain weight. Their insulin production dips or their
bodies don't use insulin effectively anymore; their
blood sugar level rises, but not high enough to have
diabetes right away.
Until recently, doctors didn't know for sure if anything
could be done to ward off diabetes in people whose blood
sugar levels had started to creep up.
That changed three years ago. In a major study, researchers
found that diet, exercise and certain medications can
slow or even reverse the progression of pre-diabetes
to diabetes. That can prevent diabetes complications
such as blindness, kidney disease and amputation.
The landmark study has led health authorities on a
twofold quest: Doctors want to identify the 41 million
Americans thought to have pre-diabetes (another 18 million
have diabetes; the vast majority, type 2) and encourage
them to take action to improve their health.
"If you know you're at risk and you can do something
about it, it's a powerful motivator," said Dr.
Michael Engelgau, with the national Centers for Disease
Control and Prevention's Division of Diabetes Translation.
The challenge is to pick out the people with pre-diabetes
without wasting time and money testing a lot of people
who don't.
One approach is being studied at Emory University.
Researchers are looking at expanding to the general
population the two-step screening process routinely
performed on pregnant women, who sometimes develop diabetes
temporarily.
Mehlan was one of the first people in the Emory study
found to have pre-diabetes.
He wasn't surprised: At 6 feet 2, he weighs 295 pounds;
his triglycerides, or levels of fat in the blood, are
high; his mother, who died two years ago, had diabetes.
Mehlan had already been trying to eat better and exercise
more, but the news of having pre-diabetes has given
those efforts a boost. Now he's cooking broccoli, cauliflower
and chicken — baked, not fried — and trying
to walk half an hour a day.
As spring approaches, he is also planning to get more
physical activity out of mowing the lawn.
There is strong evidence that making lifestyle changes,
as Mehlan is doing, helps.
The Diabetes Prevention Program study, funded by the
federal government and published in the New England
Journal of Medicine in 2002, tracked 3,200 people with
pre-diabetes. Those who exercised half an hour, five
days a week, and lost 7 percent of their weight through
a low-fat diet were 58 percent less likely to progress
to diabetes after three years.
Other people who took the drug metformin were 31 percent
less likely to get diabetes. Another trial found that
another drug, acarbose, reduced the risk of diabetes
by 25 percent.
"That was the turning point," said Dr. Charles
Clark of Indiana University, former chair of the National
Diabetes Education Program. "It got everybody's
attention."
The study led the American Diabetes Association to
issue new guidelines: anyone 45 and older who is overweight
should be checked for pre-diabetes, along with younger
people who also have other risk factors, such as high
blood pressure, low levels of HDL (or "good")
cholesterol or being African-American or Latino.
Some doctors are already testing more people for pre-diabetes.
But the two tests normally used aren't patient-friendly.
The Emory study is looking at a simpler alternative,
now done on pregnant women. It's called a glucose challenge
test. People have to drink a sugar solution, but they
don't have to fast. Blood is taken only once, and it's
possible a finger stick may do.
People who test positive would then take the more intensive
oral glucose tolerance test, considered the gold standard
for diagnosing pre-diabetes or diabetes.
The study, which started in January and is funded by
the National Institutes of Health, aims to test 2,100
people over three years. It is limited for now to employees
of Emory, Grady Memorial Hospital and Morehouse School
of Medicine and their family and friends.
If the Emory researchers find that the glucose challenge
test works well in the general population — and
is cost-effective — it could someday become part
of routine medical checkups.
SCREENING FOR PRE-DIABETES
• Who should be tested? People 45 and older who
are overweight; younger adults who are overweight and
have other risk factors: high blood pressure, high triglycerides,
low HDL ("good" cholesterol), a family history
of diabetes, gestational diabetes or birth to a child
more than 9 pounds, being African-American or Latino.
• What tests are performed: fasting plasma glucose
test or oral glucose tolerance test. Both require fasting
and blood drawn from the arm; the tolerance test also
requires a sugar drink and a second blood draw and takes
two hours.
• What is new: Researchers at Emory University
are looking at screening more of the general public
for pre-diabetes with a test routinely given to pregnant
women. It doesn't require fasting, and it may involve
only a finger stick. The study is limited for now to
employees and associates at Emory, Grady Memorial Hospital
and Morehouse School of Medicine.
Source:www.ajc.com
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