Nutrition and Coronary Heart Disease
between the levels of HDL cholesterol and CHD. This relationship is even robust
against the inclusion of the levels of LDL cholesterol into the analysis. See Gordon
(1989) for a review of the evidence on HDL and CHD (also see Pocock et al, 1989).
The inverse relationship was also found to exist in women (see Castelli et al, 1986, who
used the Framingham Study).
One could conservatively find that HDL is an important component in the reduction of
total lipoprotein risk to CHD. Risk assessments based purely upon total serum
cholesterol levels may be incorrect if there is also high levels of HDL.
From a public health perspective, concentrating on total serum cholesterol levels may be
improved upon by focusing on the LDL levels only. If more evidence comes to light in
the future (for example, that HDL does in fact have a protective effect on the risk of
CHD) then some better measure will have to be used which takes into account the
combined effects of both HDL and LDL.
Other Lipids
In addition to lipoprotein levels, apolipoproteins have been the focus of some recent
studies into CHD. Some cross-sectional clinical studies have shown a positive
relationship between apo 13, the principle component of LDL, and an inverse
relationship with apo А-l, the principle protein of HDL, and CHD. However, one
comprehensive study found that apolipoproteins had insignificant predictive power after
taking into account the standard Confounders and the ratio of total to HDL cholesterol
(Stampfer51991).
It is too early to conclude whether the measurement of apolipoprotiens should be
considered in a risk assessment of CHD. This was also the conclusion of Stampfer et al
(1991).
Triglycerides are another form of lipid that have been identified as a risk factor for
CHD9. The evidence for triglycerides as an independent risk factor for CHD is less
substantial than that of cholesterol. The relationship between triglycerides and HDL-C
9 SWSAHS Health Improvement Plan for CHD names triglycerides as one of the major modifiable risk
factors for CHD.
CHERE Project Report II- November 1999
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