Primary as well as secondary prevention trials have shown the relevance of lowering
LDL-cholesterol to reduce coronary heart disease (CHD) risk. However, although the
association between LDL-cholesterol and CHD is well recognized, there is a considerable
overlap in the distribution of plasma LDL-cholesterol levels between CHD patients
and healthy subjects. The objective of the present review article is to use data from
the Quebec cardiovascular study to demonstrate that in men, a low HDL-cholesterol
may be even more of a risk factor and a target for therapy than a high LDL-cholesterol.
Results of the Quebec cardiovascular study, a prospective study of 2103 middle-aged
men followed for a period of 5 years, have confirmed results of previous studies in
showing that plasma HDL-cholesterol concentration was an independent predictor of
a first ischemic heart disease (IHD) event which included typical effort angina, coronary
insufficiency, nonfatal myocardial infarction and coronary death. In addition, a reduced
plasma HDL-cholesterol concentration was found to have a greater impact than raised
LDL-cholesterol on the atherogenic index (total cholesterol/HDL-cholesterol ratio),
this ratio being the best variable of the traditional lipid profile for the prediction
of IHD events in the Quebec cardiovascular study. However, a low HDL-cholesterol concentration
is not often observed as an isolated disorder but also includes hypertriglyceridemia,
elevated apo B concentration, and an increased proportion of small, dense LDL particles.
These abnormalities are features of an insulin resistant-hyperinsulinemic state resulting
from abdominal obesity.
It is therefore recommended that we need to go beyond LDL-cholesterol measurement
lowering therapy for the optimal management of CHD risk. Raising plasma HDL-cholesterol
through weight loss and a healthy diet, by an increased physical activity and, if
required, by proper pharmacotherapy is therefore a legitimate therapeutic target for
the optimal prevention of CHD in a large proportion of high risk patients.