Apolipoprotein E ε4 allele is associated with vascular cognitive impairment no dementia in Chinese population

Background: The association between apolipoprotein E (APOE) epsilon 4 allele and vascular cognitive impairment no dementia (VCIND) is still controversial. Objective: To examine the relationship between the APOE epsilon 4 allele and patients with VCIND after cerebral infarction. Methods: This study included first-ever cerebral infarction patients 3-12 months after the attack at the Xuanwu Hospital between June 2012 and December 2014. Patients were divided into VCIND group and normal cognition group (NC group).The APOE epsilon 4 carriers (including epsilon 2/epsilon 4, epsilon 3/epsilon 4 and epsilon 4/epsilon 4 genotypes) and epsilon 4 allele frequency were analyzed in relation to cognition grouping after cerebral infarction. MRI features of infarctions and some known risk factors for VCIND , as confounding factors, were also analyzed for correlation with VCIND at the same time. Results: Participants (n = 707) were divided into the VCIND (n = 361) and NC (n = 346) groups. The percentage of APOE epsilon 4 carriers was higher in the VCIND group (23.6%) than in the NC group (12.7%, P < .001).The APOE 84 allele frequency was higher in the VCIND group (12.5%) than in the NC group (6.7%, P = .001). Regardless of other confounding factors, such as male gender (OR = 1.963, 95%Cl: 1.394-2.763, P < .001), age (OR = 1.034, 95%Cl: 1.017-1.052, P < .001), education (OR = 0.834, 95%Cl: 0.795-0.875, P < .001), hypertension (OR = 2.044, 95%Cl: 1.460-2.861, P < .001), hyperlipidemia (OR = 0.682, 95%Cl: 0.482-0.965, P = .031), infarction lesion diameter (OR = 1.044, 95%CI: 1.017-1.072, P = .001) and white matter lesions (OR = 1.330, 95%Cl: 1.126-1.571, P = .001), the APOE epsilon 4 allele was independently associated with VCIND (OR = 2.244, 95%Cl: 1.454-3.463, P < .001). Conclusion: These results confirms the hypothesis that the APOE epsilon 4 allele is a risk factor associated with VCIND after cerebral infarction.