Question: Does helicobacter pylori infection increase risk for ischemic stroke?

Context:
Helicobacter pylori (H. pylori) infection is reported to be associated with many extragastrointestinal manifestations, such as hematological diseases [idiopathic thrombocytopenic purpura (ITP) and unexplained iron deficiency anemia (IDA)], cardiovascular diseases (ischemic heart diseases), neurological disorders (stroke, Parkinson's disease, Alzheimer's disease), obesity and skin disorders.
Helicobacter pylori infection contributes to high risk of ischemic stroke: evidence from a meta-analysis.
This meta-analysis indicated that chronic H. pylori infection was significantly associated with an increased risk of IS, especially for non-cardioembolic IS. 
In the last years, a considerable number of studies have been performed on the relationship between infection from Helicobacter Pylori and atherosclerotic diseases, like stroke and ischemic heart disease. 
However, there are conflicting results on the relevance of chronic infection by Helicobacter pylori as a risk factor for ischemic stroke.
CONCLUSIONS: This case-control study does not reveal any strong association between chronic Helicobacter pylori infection and ischemic stroke. 
Case-control and prospective studies indicate that chronic infections, such as periodontitis, chronic bronchitis and infection with Helicobacter pylori, Chlamydia pneumoniae or Cytomegalovirus, might increase stroke risk, although considerable variation exists in the results of these studies, and methodological issues regarding serological results remain unresolved.
Chronic infections, presently discussed as stroke risk factors mainly include periodontitis and infections with Helicobacter pylori (Hp) and Chlamydia pneumoniae (Cp). 
CONCLUSION: H. Pylori gastritis is not independently associated with increased risk for stroke. 
CONCLUSIONS: Our results support the hypothesis that CagA-seropositive strains infection is significantly associated with susceptibility to ischemic strokes and coronary heart diseases. 
BACKGROUND: Previous studies suggested an association between CagA-positive H. pylori strains and ischemic stroke. 
CONCLUSIONS: Our findings suggest that CagA-positive strains of H. pylori are significantly associated to atherosclerotic stroke.
We concluded that H pylori infection is common in DM and seems to be linked to the presence of atherosclerosis and ischemic cerebrovascular stroke. 
Interesting results show that H. pylori infection affects atherosclerosis and is weakly associated with ischemic heart disease and stroke. Moreover, CagA-positive H. pylori strains may play a role in the natural history of atherosclerotic stroke.
Interestingly, the majority of the extradigestive-related literature is focused on two vascular manifestations: stroke and ischemic heart disease. 
Chronic infectious diseases that may increase the risk of stroke include periodontitis, chronic bronchitis and infections with microbial antigens, such as Helicobacter pylori and Chlamydia pneumoniae. 
CONCLUSIONS: These results suggest that H. pylori infection is a risk factor for ischemic stroke and that CD14 polymorphism is not.
 CONCLUSIONS: Our case-control study provides evidence of an association between the immune response to H. pylori , a marker of prior infection with this organism and noncardioembolic ischemic stroke.
Case-control studies and a few prospective studies have indicated that chronic infections may add to the risk of stroke and that acute infections may act as trigger factors for stroke. Such chronic infections include periodontal disease, infection with Chlamydia pneumoniae or Helicobacter pylori, and chronic bronchitis
Chronic H. pylori infection still showed an overall association with ischemic stroke (odds ratio for all subtypes combined: 2.57; 95% CI: 1.09-6.08) after adjusting for major cardiovascular risk factors. These results suggest that chronic H. pylori infection may be a triggering factor that increases the risk of acute ischemic stroke.
BACKGROUND AND PURPOSE: Studies on Helicobacter pylori infection and risk of ischemic stroke yielded variable results. 
CONCLUSIONS: Our results support the hypothesis of an association between infection with CagA-positive H. pylori strains and acute cerebral ischemia.
 Chronic infections (eg, infection with Chlamydia pneumoniae or Helicobacter pylori) were found to increase the risk of stroke; however, study results are at variance, residual confounding is not excluded, and causality is not established at present. 
CONCLUSIONS: Infection with Helicobacter pylori is associated with an increased risk of stroke and increased fibrinogen levels but these findings can be attributed to a confounding effect of socio-economic status.
 CONCLUSIONS: Hp infection represents risk factor of ischemic stoke via an interaction of Hp cytotoxins or cytokines with atherosclerotic plaques in carotic arteries.
CONCLUSIONS: The association between H pylori and acute cerebrovascular disease seems to be due to a higher prevalence of more virulent H pylori strains in patients with atherosclerotic stroke.
CONCLUSIONS: H. pylori infection appears to be significantly more frequent in middle-aged patients with acute ischemic stroke than in controls.
Chronic H pylori infection was associated with a higher risk of stroke caused by small-artery occlusion (adjusted odds ratio, 3.31; 95% CI, 1.15 to 9.56) and a lower risk of cardioembolic stroke (adjusted odds ratio, 0.21; 95% CI, 0.06 to 0.71). Overall, elevated H pylori as well as elevated C pneumoniae antibodies were not associated with ischemic stroke.
Presently, it is insufficiently established whether Helicobacter pylori infection represents a risk factor for ischemic stroke.
 H. pylori seropositivity may be an independent risk factor for stroke of atherothrombotic origin.
Appropriately randomized studies employing an antibiotic treatment for patients affected by ischemic vascular disease will answer the question of whether H. pylori has a causal role in the pathogenesis of acute myocardial infarction and ischemic stroke.
Results on the association between this bacterium and acute myocardial infarction or stroke are controversial, due to the degree of studies heterogeneity. 
Interventional randomized studies employing an antibiotic treatment for patients affected by ischemic vascular diseases will rapidly answer the question of wheather Helicobacter pylori has a causal role in the pathogenesis of acute myocardial infarction and ischemic stroke.
 CONCLUSION: Chronic H pylori infection is an independent risk factor for ischaemic cerebrovascular disease and may act, at least in part, by increasing atherosclerosis.
Presently, it is insufficiently established whether Helicobacter pylori infection represents a risk factor for ischemic stroke.
This case-control study does not reveal any strong association between chronic Helicobacter pylori infection and ischemic stroke.
However, there are conflicting results on the relevance of chronic infection by Helicobacter pylori as a risk factor for ischemic stroke.
Chronic infections (eg, infection with Chlamydia pneumoniae or Helicobacter pylori) were found to increase the risk of stroke; however, study results are at variance, residual confounding is not excluded, and causality is not established at present.
BACKGROUND AND PURPOSE: Studies on Helicobacter pylori infection and risk of ischemic stroke yielded variable results.
This case-control study does not reveal any strong association between chronic Helicobacter pylori infection and ischemic stroke.
Presently, it is insufficiently established whether Helicobacter pylori infection represents a risk factor for ischemic stroke
Chronic infectious diseases that may increase the risk of stroke include periodontitis, chronic bronchitis and infections with microbial antigens, such as Helicobacter pylori and Chlamydia pneumoniae
Studies on Helicobacter pylori infection and risk of ischemic stroke yielded variable results
Presently, it is insufficiently established whether Helicobacter pylori infection represents a risk factor for ischemic stroke
However, there are conflicting results on the relevance of chronic infection by Helicobacter pylori as a risk factor for ischemic stroke

Answer: Findings regarding association between helicobacter pylori infection and ischemic stroke risk are conflicting. There is evidence to suggest that helicobacter pylori infection is associated with increased risk for ischemic stroke and should be considered stroke risk factors. However, some studies reported no association between helicobacter pylori infection and stroke.