Apolipoprotein E Polymorphism and Stroke Subtypes in an Italian Cohort

Abstract

Background: Studies have indicated that apolipoprotein E (ApoE)-ε4 is a risk factor for ischemic cerebrovascular diseases (ICVD), but the existence of this association is still controversial. The aims of this study were: (1) to compare ApoE genotype and allele frequencies in Italian cases with ICVD and in healthy control subjects and (2) to compare ApoE allele frequencies among ischemic stroke subtypes. Methods: A hospital-based cohort of 302 Italian subjects with ICVD and 228 healthy subjects have been recruited to investigate the role of ApoE polymorphisms as risk factors for ICVD. TOAST criteria were employed to stratify ICVD cases by subtypes. Results: No significant differences in ApoE genotype and allele frequencies were found between cases and control subjects. The frequency of ApoE-ε4 was lower in cases than in control subjects (6% vs. 10.1%), although not significantly. No differences in ApoE genotype and allele frequencies were evident among ICVD subtypes. However, out of 36 ApoE-ε4 alleles 23 (3.7%) were found in subjects with ICVD related to primary degenerative arterial disease related to large vessel disease and small vessel disease, and 13 (2.1%) in remaining subjects. Using logistic regression analysis we assessed whether ApoE-ε4 allele was independently associated with risk of ICVD related to a primary degenerative arterial disease compared to other ICVD subtypes. While classical risk factors were significantly associated with higher risk for ICVD due to large vessel disease and small vessel disease than other ICVD subtypes, the role of ApoE-ε4 allele was not significant (OR 1.25, 95% CI 0.57–2.74). Conclusion: Our study shows similar ApoE-ε4 genotype and allele frequencies in patients with ICVD and in control subjects. No differences were found among different ICVD subtypes either.

Association of APOE (E2, E3 and E4) gene variants and lipid levels in ischemic stroke, its subtypes and hemorrhagic stroke in a South Indian population

“…Investigations on association of this gene with stroke have reported a number of positive associations however, there are reports that state negative association in Italian and Scottish cohorts for both IS and HS [18][19][20] [28]. Contrary to all these findings, our study however, is the first report to explain association in subtypes based on widely accepted TOAST classification of stroke.…”

Ischaemic Stroke Subtypes and Their Genetic Basis: A Comprehensive Meta-Analysis of Small and Large Vessel Stroke

“…The ApoE/ε4 polymorphism was investigated in seven studies [25,26,27,28,29,30,31] for SVD (cases 530, controls 2,101) and LVD (cases 652, controls 1,739) (fig. 4a, b).…”

Meta-Analysis of Genetic Studies from Journals Published in China of Ischemic Stroke in the Han Chinese Population

“…Despite a strong association between ApoE and stroke observed in Asian populations (OR = 1.47, 95% CI = 1.00–2.15) [81], this positive association has not yet been confirmed in studies of European populations [6, 88]. Similar to the findings in Asian populations, our data confirm that ApoE polymorphism increases the risk of stroke (OR = 2.39, 95% CI = 1.94–2.95).…”