Association between Apolipoprotein E polymorphism and myocardial infarction risk: A systematic review and meta-analysis.

Published data regarding the association between Apolipoprotein E (ApoE) genetic variation and myocardial infarction (MI) risk were not always consistent. Therefore, the current meta-analysis was conducted to derive a more precise estimation of the association between ApoE polymorphism and MI risk. PubMed and Web of Science were searched to identify relevant studies. Summary odds ratio (ORs) and 95% confidence intervals (CIs) were calculated using random-effect or fixed-effect models based on the heterogeneity of included studies. All the tests were performed using Stata 11.0. A total of 22 eligible studies were identified in this meta-analysis. The results show that ApoE ε2 and ε4 alleles were associated with MI risk. The study suggests that there is close association between ApoE polymorphism and MI risk. It shows that ApoE ε2 allele is a protective factor of MI, while ε4 allele is a risk factor of MI, especially in Caucasian and Asian population. Nevertheless, well-designed, unbiased and larger sample size studies are required to confirm the results.