Association of Apolipoprotein E Gene Polymorphism with Ischemic Stroke in Coronary Heart Disease Patients Treated with Medium-intensity Statins

Objective: To study the association of apolipoprotein E(APOE) gene polymorphism with ischemic stroke (IS) in coronary heart disease (CHD) patients treated with medium-intensity statins. Methods: The retrospective study was performed on 662 samples including 169 CHD subjects complicated with IS, 296 subjects with CHD, and 197 control subjects. The APOE gene was obtained from case files. Univariable and multivariable logistic regression analyses were utilized to recognize the possible risks of CHD and IS. Results: The frequency of epsilon 3-epsilon 4 genotype was increased in the CHD group (p=0.013) and CHD-IS group (p=0.001), the frequency of epsilon 4 allele was also increased in the CHD group (p=0.047) and the CHD-IS group (p=0.009) compared with control group. epsilon 3-epsilon 4 genotype was the independent risk for CHD and CHD-IS after adjusting for traditional risk factors with adjusted odds ratio (AOR) 2.210, 95%CI: 1.263-3.867, p=0.005) and (AOR 2.794, 95% CI: 1.539-5.072, p=0.002). The epsilon 4 allele was also significantly associated with CHD (AOR 2.126, 95%CI: 1.265-3.575,=0.004) and CHD-IS (AOR 2.740, 95%CI: 1.569-4.784, p=0.001). Conclusion: These results demonstrated that epsilon 4 allele influenced the development of CHD with or without IS, especially for the genotype of epsilon 3-epsilon 4. CHD patients carrying the epsilon 3-epsilon 4 genotype and the epsilon 4 allele were significantly associated with the incidence of IS, even if medium-intensity statins had been used.