HDL: Why it’s so important
Q: What is the most common lipid abnormality that
causes heart attack?
A: Low HDL cholesterol
That’s right—it’s not high LDL cholesterol. Look at the HDL levels in
people with heart attacks. More than likely, people with heart attacks
have low HDL of 40 mg/dl or less, and LDL will be in the 100–160 mg/dl
range (i.e., in the middle range, neither high nor low). Should these
people be treated with an LDL-lowering agent alone? Will lowering LDL
eliminate the risk posed by low HDL?
The evidence suggests that both abnormalities need to be treated. And in
the patients who already have a low LDL, strategies to raise HDL should
be initiated. The combined strategy of lowering LDL and raising HDL can,
in fact, be a powerful means of preventing future coronary events and
achieving plaque regression. In this report, we discuss the very
important findings of Dr. Greg Brown’s “HATS” Trial, conducted at the
University of Washington.
The HDL-Atherosclerosis Treatment Study (HATS) trial enrolled 160
patients (149 males), all of whom had documented coronary disease.
Coronary plaque was measured with heart catheterization. There were four
treatment arms: simvastatin (Zocor) + niacin, placebo, simvastatin +
niacin +anti-oxidant vitamins, and anti-oxidant vitamins alone.
The anti-oxidant treatment arms proved of no value in lowering coronary
events or achieving plaque regression. Let’s focus on the HDL
observations. This boils down to a comparison of two groups: the placebo
group vs. the simvastatin + niacin. Simvastatin therapy was adjusted to
achieve an LDL of 90 mg/dl or lower; niacin was adjusted to achieve an
increase in HDL of 10 mg/dl. As expected, the treatment arm patients
achieved a mildly greater reduction in plaque progression.
But what is eye-opening in this study is the magnitude of reduction of
events comparing the simvastatin + niacin group to the placebo group:
There was a 90% reduction in death and myocardial infarction (12 events
placebo;1 event simvastatin + niacin) over three years. In other words,
coronary events were nearly shut off.
 |
Want to read the rest of this Track Your Plaque Special Report?
Already a member? CLICK HERE to log-in. |
Copyright 2005, Track Your Plaque.