Systematic Review on Apolipoprotein E: A Strong Genetic Cause of Hemorrhagic Stroke.

Stroke is one of the commonest causes of mortality among the world. Hemorrhagic stroke accounts nearly 15% of all the strokes. Different risk factors have been identified, of them hypertension, anti-coagulation therapy and previous history of ischemic strokes are significant. Regarding the genetic causes of intracerebral hemorrhage (ICH) monogenic causes play a small role. It was found that Apolipoprotein E (APOE) gene has a strong association with ICH. This is a 299 amino acids long protein located in chromosome 19. APOE has three alleles, they are epsilon 2, 3 and 4. Total 10 meta-analysis were reviewed in this article which involved 52,705 participants. When looking for the association, ∈2 and ∈4 showed positive and ∈3 showed negative association with ICH. Association of ∈4 (OR mean 1.77) was stronger than that of ∈2 (OR mean 1.71).