Authors | Tsimikas S, Brilakis ES, Miller ER, McConnell JP, Lennon RJ, Kornman KS, Witztum JL, Berger PB. | |
Title | Oxidized
phospholipids, Lp(a) lipoprotein, and coronary artery disease. |
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Full source | N Engl J Med. 2005 Jul 7;353(1):46-57. | |
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Abstract | BACKGROUND:
Lp(a) lipoprotein binds proinflammatory oxidized phospholipids. We investigated
whether levels of oxidized low-density lipoprotein (LDL) measured with use
of monoclonal antibody E06 reflect the presence and extent of obstructive
coronary artery disease, defined as a stenosis of more than 50 percent of
the luminal diameter. METHODS: Levels of oxidized LDL and Lp(a) lipoprotein
were measured in a total of 504 patients immediately before coronary angiography.
Levels of oxidized LDL are reported as the oxidized phospholipid content
per particle of apolipoprotein B-100 (oxidized phospholipid:apo B-100 ratio).
RESULTS: Measurements of the oxidized phospholipid:apo B-100 ratio and Lp(a)
lipoprotein levels were skewed toward lower values, and the values for the
oxidized phospholipid:apo B-100 ratio correlated strongly with those for
Lp(a) lipoprotein (r=0.83, P<0.001). In the entire cohort, the oxidized
phospholipid:apo B-100 ratio and Lp(a) lipoprotein levels showed a strong
and graded association with the presence and extent of coronary artery disease
(i.e., the number of vessels with a stenosis of more than 50 percent of
the luminal diameter) (P<0.001). Among patients 60 years of age or younger,
those in the highest quartiles for the oxidized phospholipid:apo B-100 ratio
and Lp(a) lipoprotein levels had odds ratios for coronary artery disease
of 3.12 (P<0.001) and 3.64 (P<0.001), respectively, as compared with
patients in the lowest quartile. The combined effect of hypercholesterolemia
and being in the highest quartiles of the oxidized phospholipid:apo B-100
ratio (odds ratio, 16.8; P<0.001) and Lp(a) lipoprotein levels (odds
ratio, 14.2; P<0.001) significantly increased the probability of coronary
artery disease among patients 60 years of age or younger. In the entire
study group, the association of the oxidized phospholipid:apo B-100 ratio
with obstructive coronary artery disease was independent of all clinical
and lipid measures except one, Lp(a) lipoprotein. However, among patients
60 years of age or younger, the oxidized phospholipid:apo B-100 ratio remained
an independent predictor of coronary artery disease. CONCLUSIONS: Circulating
levels of oxidized LDL are strongly associated with angiographically documented
coronary artery disease, particularly in patients 60 years of age or younger.
These data suggest that the atherogenicity of Lp(a) lipoprotein may be mediated
in part by associated proinflammatory oxidized phospholipids. |