Association between Apolipoprotein ε4 Gene Polymorphism and Risk of Ischemic Stroke: A Meta-Analysis.
Amit Kumar1, Pradeep Kumar1, Manya Prasad1
1Department of Neurology, All India Institute of Medical Sciences, New Delhi, India.
Annals of Neurosciences
|September 21, 2016
Summary
The apolipoprotein E (APOE) ε4 allele is linked to an increased risk of ischemic stroke (IS). This association is stronger in Asian populations compared to Caucasian populations, according to a meta-analysis of genetic studies.
Area of Science:
- Genetics
- Neurology
- Epidemiology
Background:
- Conflicting results exist regarding the association between apolipoprotein E (APOE) gene polymorphism and ischemic stroke (IS) risk.
- The APOE ε4 allele is a key genetic factor under investigation for its role in IS.
- Previous studies have not definitively established the link between APOE ε4 and IS risk.
Purpose of the Study:
- To conduct a meta-analysis investigating the association between APOE ε4 gene polymorphism and ischemic stroke risk.
- To clarify the conflicting findings from previous studies on APOE ε4 and IS.
- To assess the influence of ethnicity on the APOE ε4 and IS association.
Main Methods:
- A comprehensive literature search was performed in PubMed, EMBASE, and Google Scholar for genetic association studies up to May 30, 2015.
- Included studies focused on apolipoprotein E (APOE) gene polymorphism, specifically the ε4 allele, and its association with ischemic stroke (IS) or cerebral infarction (CI).
- Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, and Begg's funnel plot was used to assess publication bias. A total of 26 case-control studies (6,397 IS cases, 19,053 controls) were analyzed.
Main Results:
- An overall significant association was found between carrying the APOE ε4 allele and an increased risk of ischemic stroke (OR 1.43, 95% CI 1.10-1.85, p = 0.007).
- Subgroup analysis by ethnicity revealed a significant association in Asian studies (OR 1.53, 95% CI 1.04-2.25, p = 0.031).
- A borderline significant association was observed in Caucasian studies (OR 1.36, 95% CI 0.95-1.93, p = 0.093).
Conclusions:
- The APOE ε4 allele is associated with a higher risk of ischemic stroke.
- The risk associated with the APOE ε4 allele appears to be greater in the Asian population compared to the Caucasian population.
- This meta-analysis provides stronger evidence for the role of APOE ε4 in ischemic stroke, particularly among Asians.
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