Influence of plasma lipids, APOE genotype and type of LDL receptor gene mutations on myocardial infarction in subjects with familial hypercholesterolemia

BACKGROUND: Our goal was to analyze the relationship of lipids and lipoproteins, APOE genotype and mutations of the LDL receptor gene with the prevalence of myocardial infarction (MI) in patients with familial hypercholesterolemia (FH) from a Southern European FH population. PATIENTS AND METHOD: We studied 108 heterozygous FH subjects aged > 35 years (41 males). It was a cross-sectional study comparing individuals with FH and MI with individuals with FH without MI. In 88 FH subjects, a mutation of the LDL receptor gene was detected. These FH subjects were divided in carriers of null mutation or no null mutations. We compared lipids and lipoproteins and prevalences of LDL receptor type mutation and APOE genotype. RESULTS: Parameters associated with MI were: age, presence of xanthomas and arcus comealis, plasma Concentrations of total cholesterol (TC), LDLc, TC/HDLc ratio > 5.3 and epsilon4 genotype of the APOE gene. Odds ratio for MI were as follows: presence of xanthomas and arcus comealis, 1.36 (Cl 95%, 1.08-1.71; P = 0.01), age > 54 years (50 th of FH group), 1.56 (Cl 95%, 1.19-2.04; P = 0.001) and plasma TC values > 332 mg/dl (50 th of PH group), 1.34 (Cl 95%, 1.05-1.71; P = 0.019). In the logistic regression model, only age and TC were significantly associated with MI. CONCLUSIONS: In FH subjects aged over 35 years from a Southern European population, MI is associated with age, plasma TIC and LDLc values, TC/HDLc ratio and the epsilon4 genotype. In addition, MI is related with age and TC plasma levels on an independent basis.