To determine the association of serum levels of lipoprotein (a) (Lp(a)) with coronary artery disease (CAD) in relation to other risk factor variables in black and white women.Design.
Retrospective case-control study.Setting.
Community of Bogalusa, Louisiana and Cardiac Catherization Laboratory at the Medical Center of Louisiana, New Orleans, USA.Subjects.
The study included 47 female cases (52% black; mean ± SD age: 50.8 ± 6.3 years) with confirmed myocardial infarction (MI) or at least 75% blockage of one or more major epicardial coronary arteries determined by angiography, and 55 controls (60% black; mean ± SD age: 49.6 ± 7.9 years) with no high grade obstructive lesion (<50% blockage) and no history of CAD.Main outcome measures.
Lipoprotein variables, homocysteine, body mass index and cigarette smoking.Results.
In the whole group, mean values of Lp(a), total cholesterol, low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (apoB) and very-low-density lipoprotein cholesterol (VLDL-C) were higher (P < 0.05-0.001) and apoA-I was lower (P < 0.05) in cases than in controls. The multivariate logistic regression analysis showed elevated levels of Lp(a) (>500 mg L−1) and LDL-C (>3.36 mmol L−1) as strong independent risk factors, with odds ratios (with 95% confidence intervals) of 13.6 (4.00-46.30) and 4.64 (1.31-16.49), respectively. ApoA-I, with an odds ratio of 0.11 (0.02-0.64), was a protective factor only at high levels (>53.6 μmol L−1). Between races, significant odds ratios were noted in the black women for Lp(a) (OR = 15.98; P < 0.01) and LDL-C (OR = 7.69; P < 0.05) and in the white women for only Lp(a) (OR = 15.23; P < 0.01).Conclusions.
Lp(a) is an important risk factor for CAD both in black and in white women.