Acute myocardial infarction in young adults: Prognostic role of angiotensin-converting enzyme, angiotensin II type I receptor, apolipoprotein E, endothelial constitutive nitric oxide synthase, and glycoprotein IIIa genetic polymorphisms at medium-term follow-up

Background A number of reports have investigated the association between va rious gene polymorphisms and the phenotypic expression of myocardial infarc tion. No investigations have evaluated the prognostic role of genetic facto rs in young people with premature coronary disease. The aim of this study w as to investigate the influence of genetic factors compared with that of co nventional risk factors on follow-up events in a population of Italian youn g adults with myocardial infarction. Methods and Results The study population consisted of 106 young patients (m ean age 40 +/- 4 years, range 23 to 45 years) with diagnosis of acute myoca rdial infarction. Clinical and genetic data from the group of patients with events during follow-up were compared with those from patients without eve nts. The following genetic polymorphisms were tested. angiotensin I convert ing enzyme, angiotensin II type I receptor, apolipoprotein E (ApoE), endoth elial constitutive nitric oxide synthase, and platelet glycoprotein IIIa. C oronary angiography was performed in 94 patients. Coronary angiography show ed coronary artery disease in 93% of patients. During follow-vp (46 +/- 12 months, range 25 to 72) the overall combined end points (cardiac death, myo cardial infarction, and revascularization procedures) accounted for 21 even ts. Family history of coronary artery disease, smoking, stenosis of the lef t anterior descending artery at coronary angiography, and ApoE polymorphism (presence of epsilon 4 allele) were significantly more prevalent (univaria te analysis) in the group of patients with events. logistic multivariate an alysis showed that ApoE polymorphism (P = .004, odds ratio [OR] 6.8, 95% co nfidence interval [Cl] 2 to 22), family history (P = .005, OR 8.3, 95% CI 2 to 35), smoking after acute myocardial infarction (P = .008, OR 10.9, 95% CI 2 to 62), and left anterior descending coronary artery disease (P = .02. OR 6.6, 95% CI 1.3 to 33) were independent predictors of adverse events. Conclusions Myocardial infarction at a young age is commonly characterized by evidence of multiple cardiovascular risk factors and by a favorable prog nosis in short- acid medium-term follow-up. Evidence of significant disease at coronary angiography suggests the presence of a premature atherosclerot ic process. ApoE polymorphism (presence of epsilon 4 allele) appears to be a strong independent predictor of adverse events, suggesting a remarkable i nfluence in the accelerated coronary disease.