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By now, most Americans
know that too much low-density lipoprotein (LDL) cholesterol
in the blood?the “bad” type—can increase
the risk of heart disease. They might even be familiar
with statin drugs, such as Crestor, Lipitor, Zocor,
or Pravachol, that can lower cholesterol levels. But
few people know that elevated levels of another substance,
C-reactive protein, can be indicative of cardiovascular
problems, even if a person’s LDL is within an
acceptable range.
While C-reactive protein
is unfamiliar to many, it has been—and continues
to be—of special interest to medical researchers.
One clinical trial that seeks to gain more information
about C-reactive protein is the JUPITER study, which
plans to enroll about 15,000 people from around the
world. The study seeks to determine whether the cholesterol-lowering
statin drug Crestor, or rosuvastatin calcium, can reduce
the risk of cardiovascular disease in people with low
LDL but high C-reactive protein levels.
New Jersey Medical School
is participating in the study, with Dr.
Norman Lasser, professor of medicine and director
of the preventive cardiology program, the investigator
at the site. “More people could potentially benefit
from taking statins, even if they don’t fit the
classic criteria for cardiovascular disease,”
says Dr. Lasser. In his practice, Dr. Lasser orders
a blood test to measure levels of C-reactive protein
in patients who might otherwise be considered borderline
for statin treatment. “If the C-reactive protein
levels are high in an otherwise healthy person, that
information convinces me to prescribe the medicine,”
he says. When a person’s C-reactive protein level
is at or above 2 mg/L, he or she could have an increased
risk of heart disease.
A Warning Sign
So what is C-reactive
protein? Dr. Lasser describes the substance as a protein
that is secreted in the liver in response to inflammation
somewhere in the body. An inflammatory response in a
healthy person is part of the way the immune system
contends with foreign substances, such as bacteria.
Usually, the inflammatory response ends, but sometimes,
with certain conditions, there remains chronic low-level
inflammation. People with inflammatory conditions such
as rheumatoid arthritis and ulcerative colitis are likely
to have high levels of C-reactive protein, as might
people who smoke, have a sedentary lifestyle and are
overweight.
When there are elevated
levels of C-reactive protein in healthy people, however,
doctors consider the molecule to be an indicator, or
marker, of cardiovascular disease. “High C-reactive
protein levels are a very early warning of heart disease,
but not the cause of it,” says Dr. Lasser. “However,
long-term inflammation can contribute to blockage within
blood vessels.”
The JUPITER Study
Preventing heart attacks
is one of the loftiest goals in preventive medicine.
One pharmaceutical company, in conjunction with major
medical research centers around the globe, is trying
to reach this goal through clinical testing of its statin
drug, rosuvastatin calcium. One of the trials is Justification
for the Use of statins in Primary prevention: an Intervention
Trial Evaluating Rosuvastatin, or the JUPITER study.
“Other studies
suggest that statins, in addition to lowering cholesterol,
can also reduce C-reactive protein levels,” says
Dr. Lasser. “This study involves people whose
cholesterol levels are within a normal range.”
The JUPITER study will
enroll thousands of people, who will be given either
rosuvastatin or a placebo (a “sugar pill”)
for about three years and have their blood tested at
specified periods to measure the levels of C-reactive
protein. People eligible for the JUPITER study include
men age 55 or older and women age 65 or older who do
not have cardiovascular disease, uncontrolled high blood
pressure, diabetes or other significant health problems.
Their LDL cholesterol levels must be normal—that
is, below 130 mg/d,.and their CRP levels at or above
2 mg/L.
Currently, Dr. Lasser
and his staff are enrolling participants in the JUPITER
study. Anyone meeting the enrollment criteria can call
for more information – a doctor’s referral
is not necessary. At the initial screening, a health
history will be taken and the person’s blood drawn
to measure levels of C-reactive protein. If the person
is found eligible for the study, he or she will be asked
to come back to the Doctors Office Center on the Newark
campus for a complete physical and a more comprehensive
panel of blood tests. The exam and blood tests are free,
and, once in the study, participants will be reimbursed
for travel. After the first three visits, patients will
be given either the placebo or the statin to take each
day and scheduled to come in twice a year for blood
testing.
“This is a very
important study that could influence how statins are
used and hopefully, help prevent cardiovascular disease,”
says Dr. Lasser.
Interested in enrolling
in the JUPITER study at New Jersey Medical School—
Call (973) 972-6107 for more information.
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