The relationship between Helicobacter pylori chronic infection and ischemic stroke subtypes:meta-analysis

Objective To conduct a meta-analysis of case-control studies for assessing association between Helicobacter pylori(Hp) and different types of ischemic stroke(IS) in order to explore whether Hp infection is the risk factor for IS and its subtypes.Methods MEDLINE,EMBASE and Cochrance Collaboration database with the time limit of 1995 to 2009 were searched.Meta-analyses were performed for case-control studies after strict screening.Heterogeneity test,sensitivity analysis and publication bias assessment were also performed.Results Eleven case-control studies were included-of which,9(1575 patients,1720 controls) were related to IS and 7 were related to large artery atherosclerotic stroke(LAA,510 patients,944 controls).The pooled OR was 1.57(95%CI:1.23—1.99).Patients with LAA had higher odds for Hp infection than controls(OR =2.24,95%CI:1.46—3.43) according to the seven studies.Random-effects model was adopted to perform heterogeneity test because of significant study heterogeneity(I~2= 58%, I~2=60%).Sensitivity analysis suggested the results of meta-analysis were reliable.However,the funnel plot suggested that the experimental results may be affected by bias,possibly resulting from lack of published studies reporting negative results in small-size sample.Conclusion Association between Hp and IS is significant and seems higher with LAA.Relation between Hp and IS needs to be further confirmed by future large sample and prospective investigations.