Test Reveals Early
Evidence of Heart Disease in Persons With Diabetes
Test can
detect calcium deposits in arteries
People with diabetes face
an increased risk of heart disease. But a new study finds a simple
screening test can detect evidence of cardiovascular disease long
before any symptoms are apparent.
In a recent issue
of the Journal of the American College of Cardiology,
researchers using results from electron-beam tomography (EBT) scans
found that people with diabetes were 70 percent more likely to have
significant calcium deposits in their arteries. They also found
that, in general, young persons with diabetes already have calcium
build-up similar to that of older people without diabetes.
EBT provides x-ray images
similar to, but more detailed than, those obtained from CT scanning.
It is particularly useful for detecting calcium deposits in the
arteries, which are associated with the development of heart disease.
"[This test] could be
helpful in treatment and in compliance, as well as in seeing what
[diabetes] is doing to the heart," says study author Julie Anne
Hoff, an assistant research professor at the University of Illinois
at Chicago.
Hoff says people with
diabetes are notoriously non-compliant when it comes to making lifestyle
changes. So, she says, if someone has this test and learns they
are already developing calcium build-up in their arteries, it might
motivate them to change.
For this study, Hoff and
her colleagues reviewed data from more than 30,000 people who had
chosen to have EBT to check on their heart health. Their ages ranged
from 30 to 90 years old, but on average, the study participants
were in their 50s. None had symptoms of heart disease.
Prior to the screening
test, each person filled out a questionnaire about their diabetes
status and other cardiovascular disease risk factors, such as high
blood pressure or high cholesterol. One thousand seventy five individuals
reported having diabetes. No distinction was made between type 1
and type 2 diabetes.
According to Hoff, 39
percent of the men with diabetes had the highest calcium deposit
scores, compared to 24 percent of the men without diabetes. In women,
those numbers were 45 percent and 23 percent, respectively. Overall,
someone with diabetes was 70 percent more likely to score in the
highest calcium deposit category than someone without the disease.
There were two groups,
however, that did not show significant differences in coronary artery
calcium scores between people with diabetes and those without the
disease. They were women between the ages of 40 and 44, and both
men and women over age 70.
In all age groups, men—whether
they had diabetes or not—had higher coronary artery calcium
scores than women did.
Younger people with diabetes
had coronary artery calcium scores comparable to older people without
diabetes, according to the study. For example, men with diabetes
between the ages of 40 and 44 had roughly the same calcium score
as men between 50 and 54 without diabetes.
Since the scans were done
on a group of "worried well" people who are actively concerned about
their health and usually taking extra steps to stay healthy, Hoff
says these results are probably an underestimation of the problem.
Dr. John Reilly, a cardiologist
at the Ochsner Clinic Foundation Hospital in New Orleans, says he
is not surprised by the findings.
"This study corroborates
what we already know. Diabetics are at risk for coronary artery
disease," Reilly says. In fact, the risk is so much higher, people
with diabetes should be treated as aggressively as someone who has
already been diagnosed with heart disease, he says.
Reilly doubts the $400
EBT scan will become a commonplace screening tool. He notes that
while some people might be encouraged to adopt a healthier lifestyle
because of high calcium scores, the opposite may also be true. People
who score low on the test may feel they do not need to monitor their
blood sugar as carefully.
Always consult your physician
for more information.
The
Link Between Diabetes and Heart Disease
Heart and vascular disease
often go hand-in-hand with diabetes. Persons with diabetes are at
a much greater risk for heart attacks, strokes, and high blood pressure.
Other vascular problems due to diabetes include poor circulation
to the legs and feet. Unfortunately, many of the cardiovascular
problems can go undetected and can start early in life.
Causes
of Heart Disease in Persons With Diabetes
Persons with diabetes
often experience changes in the blood vessels that can lead to cardiovascular
disease. In persons with diabetes, the linings of the blood vessels
may become thicker, making it more difficult for blood to flow through
the vessels. When blood flow is impaired, heart problems or stroke
can occur. Blood vessels can also suffer damage elsewhere in the
body due to diabetes, leading to eye problems, kidney problems,
and poor circulation to the legs and feet.
Prevention
and Treatment of Heart Disease in Persons With Diabetes
Even when taking proper
care of yourself, heart disease may still occur. When risk
factors are eliminated (or reduced) in a person with diabetes, the
risk for heart disease may be reduced. Taking care of yourself and
controlling your blood sugar can often slow down or prevent the
onset of complications. Other preventive treatment measures may
include:
-
See a physician
regularly.
-
Have annual electrocardiograms,
or EKGs (a test that records the electrical activity of the
heart, shows abnormal rhythms, and detects heart muscle damage),
cholesterol and blood pressure check-ups, and pulse measurement
in legs and feet.
-
Pay attention to
your symptoms and report them promptly to your physician.
-
Control your blood sugar
levels.
-
Control blood pressure
levels with lifestyle and diet changes, and/or medication.
-
Keep low-density lipoprotein
(LDL) levels (the "bad" cholesterol) at less than 100 mg/dL.
-
-
-
Eat a healthy and balanced
diet.
-
-
Limit consumption
of alcoholic beverages.
Always consult your physician
for more information.
Online
Resources
(Our Organization is not
responsible for the content of Internet sites.)
American
Diabetes Association
American
Heart Association
Diabetes
Care
Journal
of the American College of Cardiology
Nature
Medicine
|
April 2003
Diabetes
Test Can Detect Calcium Deposits in Arteries
The
Link Between Diabetes and Heart Disease
Causes
of Heart Disease in Persons With Diabetes
Prevention
and Treatment of Heart Disease in Persons With Diabetes
Thiamine
Derivative May Halt Diabetic Complications
Online
Resources
In Other Diabetes Health
News:
Thiamine
Derivative May Halt Diabetic Complications
People with diabetes often
suffer circulatory problems, vision loss, and heart attacks, to
name just a few of the untoward effects that can result from a buildup
of sugar in their tissues.
Now researchers report
that a derivative of vitamin B1 halts much of that sugar buildup,
which may lead to a vastly improved quality of life for many with
the disease.
"It's a huge breakthrough,"
says Dr. Michael Brownlee, an endocrinologist at the Albert Einstein
College of Medicine in New York City and one of the authors of the
new report, which appears in the journal Nature Medicine.
Since 1968, four major
pathways have been pinpointed for causing much of the damage of
diabetes by helping glucose-derived compounds, known as triosephosphates,
to accumulate in vascular and nerve cells, he explains.
Through his research,
Brownlee realized that by activating the enzyme transketolase, triosephosphates
could be turned into harmless chemicals.
Transketolase is a thiamine-dependent
enzyme. "Thiamine [also known as vitamin B1] itself activates it
about 20 percent," Brownlee says, but this isn't enough to stop
the glucose-derived compounds from building up in healthy cells.
"Serendipitously, I decided to give a lipid-soluble derivative so
it would be better absorbed."
In research in the laboratory
on cultured cells, the researchers found that benfotiamine increased
levels of transketolase by 300 percent. "So that was kind of lucky,"
Brownlee notes.
Benfotiamine blocked three
pathways completely. While its action has not been tested on a fourth
pathway that controls nerve cells, it may work similarly there,
he adds. At any rate, blocking three pathways is enough to prevent
many diabetes-related complications.
When 20 rats that had
suffered diabetes for nine months were given benfotiamine, diabetic
retinopathy was averted, Brownlee adds. Not a single rat developed
the retinopathy, which is a condition that occurs in many persons
with diabetes when high blood sugar damages the retina of the eye,
leading to visual problems and often blindness.
While several pharmaceutical
companies are working on releasing drugs that will halt one of the
pathways, "this is one compound that prevents all three of the pathways,"
Brownlee says.
There is every reason
to think benfotiamine will work equally well in humans, he notes,
since the mechanism in humans is the same as that of rats.
Brownlee plans to study
the effect of this compound in surrogate human cells.
Those with diabetes should
not run out to buy thiamine-rich foods or vitamins, he stresses.
"Thiamine doesn't do the same thing" as benfotiamine, and the derivative
is not sold in North America, he says.
However, there is good
news, Brownlee adds. A small company in Germany has been producing
and selling benfotiamine for some time, to treat various neuropathies.
Therefore, the medication is already used in humans and is deemed
safe, he notes.
How much benfotiamine
would be the right amount to halt the harmful pathways in humans
with diabetes is not known, Brownlee adds: "I know it's not harmful,
but I don't know what the right dose is."
Dr. Richard Hellman, an
endocrinologist at the University of Missouri-Kansas City School
of Medicine says he thinks this finding is "very promising." The
researchers have shown a very particular effect on an enzyme that
can possibly halt complications of diabetes, he notes. "I think
it's a very good study."
However, "the question,
when looking at a particular agent, always is: What else does it
do? We need to know what it [benfotiamine] does over time" and ascertain
that it doesn't cause damage in other areas of the body, he says.
"This is an important
first step," Hellman says, but "there is so much more we need to
know about this substance. I would strongly recommend that people
not try to procure it" before more extensive tests have been done
to ensure it is not harmful.
Brownlee agrees that double-blind,
placebo-controlled trials are needed. Still, "it has the potential
of being something that in quite the near future could be taken."
Always consult your physician
for more information.
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