The effect of apolipoprotein E gene polymorphism and Lp(a) levels on coronary artery disease with atrial fibrillation

Objective To explore the influence of apolipoprotein E (APOE) genotypes and blood lipid metabolism on coronary artery disease (CAD) with atrial fibrillation (AF). Methods Patients with suspected CAD were consecutively enrolled and divided into groups with or without CAD and/or AF. Blood lipid levels and APOE genotypes were determined and analysed for associations with CAD and AF. Results A total of 2048 patients were included (400 patients without CAD or AF [controls], 126 patients without CAD but with AF, 1294 patients with CAD without AF, and 228 patients with CAD and AF). Age and lipoprotein (a) (Lp[a]) levels were significantly higher in patients with CAD and AF versus those with CAD without AF. Among patients with CAD, the E3/E3 genotype and epsilon 3 allele frequencies were significantly lower in patients with AF than in those without AF, and the E4/E4 genotype and epsilon 4 allele frequencies were significantly increased. Multivariate logistic regression revealed that increased Lp(a) levels and age were independent risk factors for AF in patients with CAD. Conclusion Among patients with CAD, those with AF had increased age, epsilon 4 frequencies and Lp(a) levels. Age and Lp(a) levels may be independent risk factors for AF in patients with CAD.