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Several epidemiologic studies have evaluated the association between intercellular adhesion molecule-1 (ICAM-1) gene K469E polymorphism and stroke, but the results were inconsistent. The present meta-analysis was performed to investigate the relationship between K469E polymorphism and stroke in the Chinese population. A comprehensive search for related studies from the electronic databases of PubMed, Embase, Web of Science, CBMdisc and CNKI as well as a manual search of the references of identified articles was performed. Data were extracted to calculate for allelic, additive, dominant and recessive models using pooled odds ratios (ORs) along with 95% confidence intervals (CIs) by Review Manager 5.0 and Stata 11.0. Different effect models, subgroup analysis, sensitivity analysis, publication bias and power calculations were used to improve the comprehensive analysis. Finally, a total of 12 studies containing 1593 cases and 1555 controls were included in the final meta-analysis. No evidence of significant association between ICAM-1 gene K469E polymorphism and stroke was found in all four models (allelic model: OR = 1.07, 95%CI = 0.78-1.47; additive model: OR = 1.21, 95% CI = 0.67-2.16 (EE vs. KK); OR = 1.04, 95%CI = 0.75-1.45 (EK vs. KK); dominant model: OR = 1.07, 95% CI = 0.73-1.56; and recessive model: OR = 1.18, 95% CI = 0.77-1.83, respectively) based on the overall population, as well as subgroup analysis and sensitivity analysis. In conclusion, the present meta-analysis showed no evidence of significant association between ICAM-1 gene K469E polymorphism and stroke in the Chinese population. Nonetheless, this conclusion should be interpreted cautiously due to the low statistical power and considerable heterogeneity. Therefore, larger sample-size studies with homogeneous cases and well-matched controls are needed to further address this correlation. [ABSTRACT FROM AUTHOR]

Background: The association between methylenetetrahydrofolate reductase (MTHFR) gene A1298C polymorphism and adult stroke remains controversial. The present article was designed to clarify this relationship through pooled analysis of the numerous epidemiological studies focusing on this association. Methods: We comprehensively searched all published papers in electronic database including PubMed, Embase, Web of Science, Chinese Biomedical Literature on disc (CBMdisc) and China National Knowledge Infrastructure (CNKI) up to 2013. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) for allelic (C allele vs. A allele), additive (CC vs. AA), dominant (CC+AC vs. AA), and recessive (CC vs. AA+AC) models were calculated. Subgroup and sensitivity analyses were performed to detect the heterogeneity and examine the reliability of results, respectively. Begg's funnel plots and Egger's regression test were used to assess the potential publication bias. Results: A total of fifteen studies containing 2,361 cases and 2,653 controls were included in the final meta-analysis. The combined results of overall analysis showed that there was significant association between MTHFR gene A1298C polymorphism and adult stroke (allelic model: OR = 1.36, 95% CI = 1.11-1.67; additive model: OR = 1.88, 95% CI = 1.12-3.18; dominant model: OR = 1.33, 95% CI = 1.08-1.65 and recessive model: OR = 1.77, 95% CI = 1.07-2.94, respectively). On subgroup analysis by ethnicity of study population, significant association was shown in meta-analysis based on Asian population (allelic model: OR = 1.40, 95% CI = 1.19-1.65; additive model: OR = 2.58, 95% CI = 1.34-4.96; dominant model: OR = 1.44, 95% CI = 1.20-1.73 and recessive model: OR = 2.12, 95% CI = 1.20-3.76, respectively), but not in Caucasian population (allelic model: OR = 1.30, 95% CI = 0.93-1.82; additive model: OR = 1.65, 95% CI = 0.81-3.33; dominant model: OR = 1.17, 95% CI = 0.86-1.61 and recessive model: OR = 1.70, 95% CI = 0.83-3.50, respectively). In addition, the heterogeneity was effectively removed or decreased by limiting the included studies with population of Asian ethnicity. Furthermore, the corresponding pooled ORs were not materially changed in all genetic models of meta-analysis after limiting the included studies with population-based controls. However, except the recessive model, publication bias presented in the allelic, additive, dominant models identified by the Begg's funnel plots and Egger's regression test. Conclusions: In conclusion, the overall analysis suggests that MTHFR gene A1298C polymorphism plays an important role in the development of adult stroke. Genotype CC of MTHFR-1298A/C could increase the risk of stroke and may act as a predictor for clinical evaluation, especially in the Asian population. More studies with large-scale and different ethnicities are required to further confirm our findings. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Epidemiological studies have evaluated the association between Toll-like receptor 4 (TLR4) gene Asp299Gly (rs4986790) polymorphism and the risk of ischemic cerebrovascular disease, but the results are inconsistent. In an effort to clarify earlier inconclusive results, a meta-analysis was performed. We searched the PubMed, Web of Science, Embase, Cochrane database, Clinicaltrials.gov, Current Controlled Trials, CNKI, CBMdisc, Chinese Clinical Trial Registry and Google Scholar until up to 20 July 2013. Additionally, hand searching of the references of identified articles was performed. Original observational studies investigating the association between TLR4 gene Asp299Gly polymorphism and ischemic cerebrovascular disease risk were included. All statistical analyses were performed using Stata 11.0. The search strategy identified 1038 potentially relevant articles, seven of which were included in the final meta-analysis, covering a total of 1767 cases and 2785 controls. Overall, no significant association was found between TLR4 gene Asp299Gly polymorphism and ischemic cerebrovascular disease risk (for G allele versus A allele: OR = 0.95, 95% CI = 0.75-1.21, p = 0.69; for G/G+A/G versus A/A: OR = 0.96, 95% CI = 0.75-1.22, p = 0.73). In addition, the similar results were obtained in the sensitivity analysis based on studies with the high quality. In summary, the present meta-analysis indicates that TLR4 gene Asp299Gly polymorphism is not associated with increased ischemic cerebrovascular disease risk. [ABSTRACT FROM AUTHOR]

Background: Numerous epidemiological studies have evaluated the associations between ATP-binding cassette transporter 1 (ABCA1) R219K (rs2230806) and M883I (rs4149313) polymorphisms and atherosclerosis (AS), but results remain controversial. The purpose of the present study is to investigate whether these two polymorphisms facilitate the susceptibility to AS using a meta-analysis. Methods: PubMed, Embase, Web of Science, Medline, Cochrane database, Clinicaltrials.gov, Current Controlled Trials, Chinese Clinical Trial Registry, CBMdisc, CNKI, Google Scholar and Baidu Library were searched to get the genetic association studies. All statistical analyses were done with Stata 11.0. Results: Forty-seven articles involving 58 studies were included in the final meta-analysis. For the ABCA1 R219K polymorphism, 42 studies involving 12,551 AS cases and 19,548 controls were combined showing significant association between this variant and AS risk (for K allele vs. R allele: OR = 0.77, 95% CI = 0.71–0.84, P<0.01; for K/K vs. R/R: OR = 0.60, 95% CI = 0.51–0.71, P<0.01; for K/K vs. R/K+R/R: OR = 0.69, 95% CI = 0.60–0.80, P<0.01; for K/K+R/K vs. R/R: OR = 0.74, 95% CI = 0.66–0.83, P<0.01). For the ABCA1 M883I polymorphism, 16 studies involving 4,224 AS cases and 3,462 controls were combined. There was also significant association between the variant and AS risk (for I allele vs. M allele: OR = 0.85, 95% CI = 0.77–0.95, P<0.01). Conclusions: The present meta-analysis suggested that the ABCA1 R219K and M883I polymorphisms were associated with the susceptibility to AS. However, due to the high heterogeneity in the meta-analysis, the results should be interpreted with caution. [ABSTRACT FROM AUTHOR]

Abstract: Increasing epidemiological studies have focused on the associations between interleukin-6 (IL-6) gene −174G>C polymorphism and atherosclerotic diseases, but the results are still controversial. This meta-analysis was designed to identify whether this association exists. PubMed, Embase, Web of Science, Cochrane database, Clinicaltrials.gov and Current Controlled Trials, Chinese Clinical Trial Registry, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. The crude odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the IL-6 gene −174G>C polymorphism and atherosclerosis ( AS ) risk. The subgroup analyses were made on the following: ethnicity, atherosclerotic diseases and source of controls. Finally, 50 studies (15,029 cases and 18,485 controls) were included in this meta-analysis. Overall, no significant association was found between the IL-6 gene −174G>C polymorphism and AS risk (for C allele vs. G allele: OR=1.02, 95% CI=0.94–1.11, p =0.64; for C/C vs. G/G: OR=1.01, 95% CI=0.85–1.21, p =0.88; for C/C vs. C/G+G/G: OR=0.97, 95% CI=0.84–1.12, p =0.68; for C/C+C/G vs. G/G: OR=1.07, 95% CI=0.97–1.17, p =0.18). In the subgroup analyses, significant associations were found between the IL-6 gene −174G>C polymorphism and AS in non-Caucasian group (for CC+CG vs. GG: OR=1.22, 95% CI=1.06–1.41, p =0.005), other atherosclerotic diseases group (for C allele vs. G allele: OR =0.75, 95% CI=0.61–0.93, p =0.008; for C/C vs. G/G: OR=0.56, 95% CI=0.38–0.81, p =0.002; for C/C vs. C/G+G/G: OR=0.60, 95% CI=0.45–0.79, p =0.0004) and population-based group (for C allele vs. G allele: OR=1.09, 95% CI=1.00–1.18, p =0.04; for CC+CG vs. GG: OR=1.15, 95% CI=1.04–1.27, p =0.005). In summary, the present meta-analysis suggests that the IL-6 gene −174GC polymorphism is associated with the susceptibility to AS. However, due to the high heterogeneity in the meta-analysis, the results should be interpreted with caution. [Copyright &y& Elsevier]