Associations of TNFα-308G/A and TNFα-238G/A Polymorphisms with Ischemic Stroke in East Asians and Non-East Asians: A Meta-Analysis.

AIMS

Two well-characterized polymorphisms in the tumor necrosis factor (TNF) gene, TNFα-308G/A and TNFα-238G/A, are thought to play important roles in the etiology and pathogenesis of ischemic stroke. Due to ethnic diversity, studies of the associations between these polymorphisms and ischemic stroke are inconclusive. Thus, we conducted a meta-analysis to derive more precise estimates of these associations in East Asians and non-East Asians.

MATERIALS AND METHODS

We searched relevant publications in the PubMed, Embase, and Medline databases. A total of 18 studies with 8075 patients and 8217 controls were included. The odds ratios (OR) and 95% confidence intervals (CIs) were evaluated to identify associations.

RESULTS

Analyses of the full dataset failed to identify any significant association between ischemic stroke and the TNFα-308G/A (A vs. G: OR = 0.86, 95% CI: 0.72-1.02, p = 0.08) or TNFα-238G/A (A vs. G: OR = 0.94, 95% CI: 0.67-1.32, p = 0.72) polymorphism. In subgroup analysis by ethnicity, TNFα-308G/A was found to be a protective factor (A vs. G: OR = 0.69, 95% CI: 0.56-0.85, p = 0.01) against ischemic stroke in the East Asians. No significant association was detected between ischemic stroke risk and TNFα-238G/A in the East Asians (A vs. G: OR = 0.82, 95% CI: 0.57-1.16, p = 0.26) or non-East Asians (A vs. G: OR = 1.61, 95% CI: 0.90-2.88, p = 0.11).

CONCLUSIONS

The results of this meta-analysis suggest that there is no significant relationship between ischemic stroke and TNFα-308G/A or TNFα-238G/A. However, according to subgroup analysis of East Asians, TNFα-308G/A is a protective factor against ischemic stroke.