title: Association between Helicobacter pylori infection and stroke: a meta-analysis of prospective observational studies.
abstract: BACKGROUND
  Some studies have suggested an association between Helicobacter pylori infection and the risk of stroke, but the relationship remains controversial. The aim of this study was to obtain a more comprehensive estimate of H. pylori on the risk of stroke by performing a meta-analysis.
  
  
  METHODS
  A computerized search of PubMed, EMBASE, and the Cochrane library (including CENTRAL) up to February 2014 was performed to identify eligible studies. Prospective studies reported that a multivariate-adjusted estimate for the association between H. pylori and stroke were included. A random-effects model was used to calculate the overall combined risk.
  
  
  RESULTS
  Ten prospective observational studies (6 cohort studies, 4 nested case-control, or case-cohort studies within cohort studies) were included in the meta-analysis. The overall combined odds ratio for H. infection and stroke was .96 (95% confidence interval, .78-1.14). Similar results were yielded in patients with cytotoxin-associated gene-A seropositive strains. The combined estimates were robust across sensitivity analyses and had no observed publication bias.
  
  
  CONCLUSIONS
  In conclusion, our formal meta-analysis indicated no strong association between H. pylori infection and stroke, neither in those with cytotoxin-associated gene-A-positive infection. We believe that future epidemiologic studies of H. pylori and stroke are unlikely to be fruitful.
authors.affiliation: Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Yu
authors.affiliation: Department of Neurology, The Second Affiliated Hospital of Nanchang University, Guangzhou, People's Republic of China.
authors.forename: Yangbo
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Oncology, The Second Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China.
authors.forename: Jiangwu
authors.initials: J
authors.lastname: Ding
authors.affiliation: Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Xie
authors.affiliation: Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China. Electronic address: lunonghua@163.com.
authors.forename: Nonghua
authors.initials: N
authors.lastname: Lu
mesh_terms: D016022:Case-Control Studies; D015331:Cohort Studies; D016481:Helicobacter Infections / Q000150:complications* / Q000453:epidemiology*; D016480:Helicobacter pylori / Q000235:genetics; D006801:Humans; D064887:Observational Studies as Topic; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000150:complications* / Q000453:epidemiology*
keywords: Helicobacter pylori; meta-analysis; prospective study; stroke