參考資料

Journal Report
01/28/2003

CRP improves cardiovascular risk prediction in metabolic syndrome


DALLAS, Jan. 28 – In women with metabolic syndrome, blood levels of C-reactive protein (CRP)
can help predict cardiovascular risk, researchers reported today in Circulation: Journal of
the American Heart Association.

CRP is an indicator of inflammation. High levels of CRP have been linked to increased risk of
heart attack, stroke, and type 2 (non-insulin dependent) diabetes.

Metabolic syndrome is the clustering of three or more of five conditions: abdominal obesity,
high triglycerides, low levels of “good” HDL cholesterol, high blood pressure,
and high glucose (blood sugar). It is associated with a significant increase in cardiovascular risk.

In the study, Harvard researchers examined data from 14,719 healthy participants enrolled in
the ongoing Women’s Health Study (WHS), which began in late 1992. They excluded women
receiving estrogen replacement therapy or who had diabetes.

Among the women, 3,597 had metabolic syndrome when they entered the WHS study.

After eight years of follow-up, the age-adjusted rate for heart attacks, strokes, operations
to restore blood flow to the heart, and death from cardiovascular disease for those with
metabolic syndrome and CRP levels above 3.0 milligrams per Liter (mg/L) was 5.9 per 1,000
people per year. For those with the metabolic syndrome but CRP levels less than 3.0 mg/L,
the event rate was 3.4.

An analysis of the women with metabolic syndrome showed that those with the highest CRP
levels (greater than 3.0 mg/L) were 2.1 times more likely to have a cardiovascular event
than those with the lowest CRP levels (less than 1.0 mg/L).

“We have previously shown that CRP predicts cardiovascular risk in healthy individuals.
Now we have evidence that CRP also does a very good job of distinguishing lower, moderate,
and higher risk, even among people with metabolic syndrome,” says lead author Paul M.
Ridker, M.D., a professor of medicine at Harvard and director of the Center for
Cardiovascular Disease Prevention at Brigham and Women’s Hospital in Boston.

Although his team studied only women, “we believe these data are likely true for men because
other studies have linked CRP to individual components of the metabolic syndrome,” he says.

These results also add evidence to the hypotheses that inflammation plays a significant role
in cardiovascular disease.

He also notes that “we don’t yet have evidence that lowering CRP will necessarily lower
cardiovascular risk. Studies evaluating this idea are only now starting.”

Lifestyle changes such as a heart-healthy diet, regular exercise, weight loss and stopping
smoking can reduce the risk of heart disease and diabetes.

Ridker’s results support the new American Heart Association/Centers for Disease Control
recommendations on the clinical use of CRP testing, which are published in the same issue
of Circulation, says Thomas A. Pearson, M.D., Ph.D., co-chair of the writing group that
crafted the new recommendations. “These recommendations suggest that CRP testing should
be limited to those patients with intermediate risk, such as women with metabolic syndrome,
and that hs-CRP testing is an optional tool to further define their coronary risk.

“Dr. Ridker’s results confirm the importance of the metabolic syndrome as a predictor of
coronary events in women,” Pearson adds.

Co-authors are Julie E. Buring, M.D.; Nancy R. Cook, M.D.; and Nader Rifai, M.D.

This study was supported partly by the National Heart, Lung, and Blood Institute.



NR03 – 1006 (Circ/Ridker)

Blood urea nitrogen (BUN) is a measure of how well the kidneys are working.
Urea is a nitrogen-containing waste product created in the body through the
metabolism and breakdown of protein. If the kidneys are not working properly,
the levels of BUN will build up in the blood. Dehydration and excessive
bleeding can also elevate the BUN content of blood. Malnutrition may be
associated with low BUN values.

Creatinine is a compound created by the breakdown of muscle protein. Creatinine
is measured to determine kidney function, and the kidneys filter and excrete
creatinine. If they are not functioning properly, creatinine can build up in
the bloodstream. Kidney failure may result from high creatinine levels. Both
dehydration and muscle damage from trauma can raise creatinine levels. Compar
ing BUN and creatinine helps to locate the reason for kidney dysfunction.
Measuring glucose

Glucose is a simple sugar that is released into the body during digestion as
the cells main source of energy. When the body metabolizes glucose, energy
to fuel essential body functions is produced. Blood glucose is tightly
regulated in the body by two hormones called insulin and glucagon. Insulin
increases the amount of glucose available to the bodys cells, and glucagon
causes the bodys stores of glucose - called glycogen - to break down,
releasing glucose into the blood. Glucose levels in children may be high
if they have diabetes or are attempting to fight off severe infections.
Low blood glucose levels - or hypoglycemia - can occur if a child has
liver damage or is malnourished.