Role of lipid, apolipoprotein levels and apolipoprotein E genotype in young Italian patients with myocardial infarction

Background and Aim: Studies of young patients with acute myocardial infarct ion (AMI) have demonstrated that conventional risk factors are usually resp onsible for their premature atherosclerosis. No account has yet been publis hed of the risk profile of young Italians surviving an AMI. In this study t he conventional risk factors, lipids and apolipoproteins, and apolipoprotei n E (APOE) allele distribution were evaluated m 98 consecutive AMI survivor s (94 males, 4 females) aged 40.1+/-3.9 for at least three months after the ir acute event. These survivors were matched for age, sex, body mass index and presence of diabetes mellitus with 98 controls selected from subjects a dmitted to the same hospital for other reasons. Methods and Results: Lipid profiles and APOE polymorphism were determined i n both groups. Coronary angiography during hospitalization showed the absen ce of critical stenosis in 6.6% of the survivors, mono-vessel disease in 57 .7%, and multi-vessel disease in 35.5%. The survivors had a higher frequenc y of smoking, hypertension, family history for coronary artery disease (CAD ) and dyslipidemia, and a much greater frequency of 3 or more risk factors than the controls: Odd ratios (OR) 7.4, 95% confidence interval (CI) 2.5-18 .6 p=0.0000. Significant differences were found between the groups for trig lycerides (p=0.000002), total cholesterol (p=0.003), LDL-cholesterol (p=0.0 12), HDL-cholesterol (p=0.0002), apolipoprotein AI (p=0.00001), and Apolipo -protein B (p=0.000001). No differences were observed in APOE allele distri bution (APOE*4 0.11 vs 0.08, APOE*3 0.86 vs 0.89, APOE*2 0.03 vs 0.03), nor in lipid profile when both higher risk genotype (E3/4, E4/4, E2/4) and low er risk genotype groups (E2/2, E2/3, E3/3) were analysed OR were calculated as measures of the association of the E4-positive genotypes with AMI. They indicated a non-significant increase in risk of AMI when the survivors wer e compared with the controls (OR 1.78, 95% CI 0.84-3.70, p=0.13). Conclusions: This study provides further evidence that conventional coronar y risk factors are usually present in young AMI patients. The APOE*4 allele was associated with a 1.8 non-significant increase in the risk of AMI in o ur group with premature CAD. Comparison with controls showed that the prese nce of three or more risk factors sharply increased the probability of prem ature CAD and that hyper-triglyceridemia is art independent risk factor The data on APOE polymorphism are less certain and a larger study is needed Nu tr Metab Cardiovasc Dis (1999) 9: 118-124. (C) 1999, Medikal Press.