Apolipoprotein A-I and B levels and the risk of ischemic heart disease during a five-year follow-up of men in the Québec cardiovascular study

• Published in: Circulation (New York, N.Y.) N.Y.), 1996-08, Vol.94 (3), p.273-278
• Main Authors: LAMARCHE, B, MOORJANI, S, LUPIEN, P. J, CANTIN, B, BERNARD, P.-M, DAGENAIS, G. R, DESPRES, J.-P
• Format: Article
• Language: English
• Subjects: Aged; Apolipoprotein A-I - blood; Apolipoproteins B - blood; Biological and medical sciences; Cardiology. Vascular system; Cholesterol, HDL - blood; Cohort Studies; Coronary heart disease; Follow-Up Studies; Forecasting; Heart; Humans; Male; Medical sciences; Middle Aged; Myocardial Ischemia; Proportional Hazards Models; Prospective Studies; Risk Factors; Survival Analysis
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/01.CIR.94.3.273

Results obtained largely from case-control studies have suggested that an elevated plasma concentration of apolipoprotein (apo) B may be considered an important risk factor for ischemic heart disease (IHD). Prospective data on the relevance of measuring apo A-I and apo B levels in the assessment of IHD risk, however, remain sparse as well as controversial. Plasma lipid, apo B, and apo A-I levels as well as other risk factors were evaluated at baseline in 1985 in a sample of 2155 men (45 to 76 years old) who were followed for a period of 5 years for clinical signs of IHD. Proportional-hazards analyses indicated that plasma apo B concentrations measured at entry were strongly associated with onset of IHD (relative rate, 1.4; 95% confidence interval [CI], 1.2 to 1.7), independent of covariables such as age, smoking, diabetes mellitus, and systolic blood pressure. Controlling for triglycerides, HDL cholesterol, and total/HDL cholesterol ratio did not eliminate the relationship between plasma apo B levels and IHD. The association between apo A-I and IHD was of lower magnitude (relative rate, 0.85; 95% CI, 0.7 to 1.0), and adjustment for selected plasma lipid and lipoprotein levels eliminated this association. Stepwise logistic regression analysis revealed that, among metabolic variables, apo B was the strongest correlate of IHD. These prospective results emphasize the importance of apo B as a risk factor for IHD. Apo B may be regarded as a relevant tool in the assessment of IHD risk in men, because it may provide information that would not be obtained from the conventional lipid-lipoprotein profile.