Information On Homocysteine (High)
A high serum concentration of homocysteine is associated with increased risk for Coronary Heart Disease (CHD).
The AHA recently published an advisory on homocysteine that provides an
in-depth review of the relation between homocysteine and CVD. Several
mechanisms whereby elevated homocysteine predisposes to CVD have been
postulated. However, it remains to be proved in controlled clinical
trials that a reduction in serum homocysteine levels will reduce risk
for CHD. In some patients, nonetheless, high levels of homocysteine can
be lowered by recommended daily intake of folic acid. If homocysteine
levels are elevated, patients should be encouraged to consume the
recommended daily intake of folic acid, as well as vitamins B6 and B12.
Routine measurement of homocysteine levels was not recommended for
purposes of risk assessment, but measurement is optimal in high-risk
patients.
The observation that many heart attack victims have normal
cholesterol levels underscores the need to identify other risk factors
for atherosclerosis. Of several
substances in the blood that are now thought to predict odds for
vascular disease, the amino acid, homocysteine, is the one for which
the case is strongest. The findings suggest a simple way to prevent
heart attacks because homocysteine levels can be lowered by taking the
B vitamin, folic acid. In a 1995 review of work exploring the
relationships among homocysteine levels, folic acid and blood vessel
disease (JAMA, vol. 274, pp.1049-1057), University of Washington
researchers proposed that increasing folic acid intake might prevent as
many as 50,000 heart attack deaths a year.
An important risk factor for vascular disease is elevated blood
concentrations of homocysteine, and one of the risk factors for
hyperhomocysteinemia is inadequate intake of the vitamins involved in
homocysteine metabolism. Homocysteine is an intermediate in the
interconversion of the amino acids methionine and cysteine, a process
requiring at various stages, activated folic acid (tetrahydrofolate and
N-methyl-tetrahydrofolate) and enzymes containing the cofactors vitamin
B6 (pyridoxal phosphate) and vitamin B12 (methyl- cobalamin).
Homocysteine is toxic to the vascular endothelium but undergoes rapid
enzymatic metabolism so it is not normally present in the bloodstream.
However, a surprisingly large number of people have elevated blood
levels of homocysteine, in some cases because of a genetic inability to
metabolize homocysteine and in other cases because of a deficiency of
one or more vitamin cofactors required for its conversion. Such
individuals are at increased risk of peripheral vascular,
cardiovascular, and cerebrovascular disease.
Folic acid is thought to protect against heart disease because it
breaks down homocysteine and allows it to be cleared from the blood
stream. The University of Washington review referred to 11 studies of
folic acid's effects on homocysteine levels. Among these was the Tufts
research, which showed for the first time that inadequate intake of the
vitamin is the main determinant of the homocysteine-related increase in
the risk of carotid blockage.
The
nutrients mentioned above reflect the major nutritional supplements
that may help the condition. Please do remember however that
nutritional supplementation is an adjunct to medical treatment and in
no way replaces medical treatment.