TUESDAY, Feb. 12 (HealthDay News) -- A new study showing that
high levels of triglycerides were strong predictors of cardiac
trouble strengthens the case for including measurement of the blood
fats in prevention programs.
"Triglycerides traditionally have been viewed as second-class
citizens," said Dr. Michael Miller, director of preventive
cardiology at the University of Maryland Medical Center and lead
author of the report in the Feb. 12 issue of the
Journal of the American College of Cardiology.. "LDL
cholesterol has always taken center stage. We know that LDL is
intimately involved in bringing cholesterol to scavenger cells,
which deposit them to form plaques in the arteries. This study
shows that triglycerides in and of themselves are also lipids to
blame."
The original study was designed to test the effectiveness of two
LDL-lowering statins, Pravachol and Lipitor, in reducing recurring
coronary disease after a heart attack. The new study went over the
data on the 4,162 participants in the trial, looking at the
association between triglyceride levels and the incidence of heart
problems and death.
"The patients who had heart attacks came back after 30 days,"
said Miller. "We measured LDL levels and triglyceride levels and
followed them over the next two years, evaluating for the
occurrence of new events and death. If a patient had triglyceride
levels below 150 [milligrams per deciliter], there was a 27 percent
lower risk of having a new event over time. After multiple
adjustments, for such things as age, diabetes, high blood pressure
and obesity, the risk reduction was 20 percent."
Unlike LDL cholesterol, for which there is a recommended blood
level, 70 or below, there is no recommended blood triglyceride
level, Miller said, but 150 milligrams per deciliter or below is
"considered as desirable."
When the participants were divided into four groups on the basis
of both LDL and triglyceride levels, those in the group with under
150 for triglycerides and under 70 for LDL did the best, with a 28
percent lower risk than those in the group with the highest
readings for both LDL and triglycerides, he said.
The results obviously need verification, Miller said. "At the
present time, we don't have a recommendation for triglyceride
lowering, so the next logical step is a study to determine whether
lowering triglycerides and LDL reduces risk more than lowering LDL
alone," he said. Two such studies are in progress, Miller
noted.
Previous research has already pointed toward such a connection:
A study that appeared in
Neurology last December found a link between triglycerides
and stroke risk, while research published in the
Journal of the American Medical Association last July showed
that when high triglyceride levels showed up in nonfasting
cholesterol tests, there was an increased risk for a future heart
attack.
Dr. Leslie Cho, an interventional cardiologist who is director
of the Women's Cardiovascular Center of the Cleveland Clinic, noted
that the new report "is not a huge surprise."
"The unique thing about this study is that even if you control
bad LDL cholesterol to less than 70, you still need to look at
triglycerides," Cho said.
The problem with triglycerides is that "they are the most
unstable fats in the body," so that at least two readings are
needed to get an accurate measure of blood levels, she
explained.
Meanwhile, Miller said, "I am proactive about both LDL
cholesterol and triglycerides." Several measures can be taken to
lower triglyceride levels -- many of them already recommended on
general principles for reduction of coronary risk.
One is to eat a Mediterranean diet, rich in fish. Omega-3 fatty
acids can lower triglyceride levels, as can niacin, and exercise
has a beneficial effect, Miller said. Statins also have some
triglyceride-lowering effect, he noted.
"If you can effectively get both LDL cholesterol and
triglycerides down, you are going to do better," Miller said.
More information
You can learn what triglycerides are and why they matter from
the
American Heart Association.
