Background: Ischemic stroke (IS) is a complex multifactorial and polygenic disease. Studies on association between Factor V G1691A gene polymorphism and ischemic stroke have shown conflicting results. To address this issue, we conducted a meta-analysis to determine the precise role of Factor V gene polymorphism with risk of ischemic stroke
Materials and Methods: We searched electronic databases PubMed, Trip Data Base, Medline, EMBASE and Google Scholar (last search dated March 2017). Pooled odds ratios (ORs) with 95% confidence intervals (CIs) from random- and fixed-effects models were calculated.
Results: Forty case-control studies fulfilled our inclusion criteria comprising 6860 patients and 18025 controls. 19 studies were conducted in young adults (mean age < or = 40 years), 17 studies were conducted in the subjects with old onset of stroke (mean age > 40) years and 5 studies did not report the mean age at recruitment. The significant associations between Factor V G1691A gene polymorphism and risk of ischemic stroke were observed in dominant model (odds ratio [OR] 1.40; 95% CI:1.22 to 1.62, P-value = <0.001. Stratified analysis suggested strong association of Factor V and risk of Ischemic stroke in cases with young onset (<=40 years) odds ratio 1.84; 95% CI: 1.47 to 2.30) but failed to reach to threshold of statistical significance in cases who had onset of stroke at old age (>40 years). Across all the included studies, Factor V heterozygous state was observed in 423 of 6860 cases (6.1%) and 1069 of 18025 controls (5.9%), yielding a fixed effect odds ratio of 1.40 (95% CI: 1.22 to 1.62).
Conclusion: Factor V G1691A genetic polymorphism was associated with risk of ischemic stroke mainly in young adults. Further prospective studies are needed to validate these findings.
Keywords: Factor V gene polymorphism, Meta-analysis,Ischemic stroke, Cardiovascular Disorder, Stroke