Association between Helicobacter pylori infection and stroke: a meta-analysis of prospective observational studies

Risk of Ischemic Stroke in Relation to Helicobacter pylori Infection and Eradication Status: A Large-Scale Prospective Observational Cohort Study

Background/Aims

: A few studies have suggested the association between Helicobacter pylori (HP) infection and ischemic stroke. However, the impact of HP eradication on stroke risk has not been well evaluated. This study aimed to assess the influence of HP eradication on the incidence of ischemic stroke, considering the potential effect of sex.

Methods

: This prospective observational cohort study was conducted at Seoul National University Bundang Hospital, from May 2003 to February 2023, and involved gastroscopy-based HP testing. Propensity score (PS) matching was employed to ensure balanced groups by matching patients in the HP eradicated group (n=2,803) in a 3:1 ratio with patients in the HP non-eradicated group (n=960). Cox proportional hazard regression analysis was used to evaluate the risk of ischemic stroke.

Results

: Among 6,664 patients, multivariate analysis after PS matching indicated that HP eradication did not significantly alter the risk of ischemic stroke (hazard ratio, 0.531; 95% confidence interval, 0.221 to 1.270; p=0.157). Sex-specific subgroup analyses, both univariate and multivariate, did not yield statistically significant differences. However, Kaplan-Meier analysis revealed a potential trend: the females in the HP eradicated group exhibited a lower incidence of ischemic stroke than those in the HP non-eradicated group, although this did not reach statistical significance (p=0.057).

Conclusions

: This finding suggests that HP eradication might not impact the risk of ischemic stroke. However, there was a trend showing that females potentially had a lower risk of ischemic stroke following HP eradication, though further investigation is required to establish definitive evidence.

Causal associations of circulating Helicobacter pylori antibodies with stroke and the mediating role of inflammation

BACKGROUND

Observational studies have shown that Helicobacter pylori (H. pylori) infection and H. pylori antibodies are associated with an increased risk of stroke. However, which and how H. pylori antibodies serve as the causal determinant of the development of stroke remains largely unknown.

METHODS

Genome-wide association studies (GWAS) on seven different antibodies of H. pylori-specific proteins, stroke, and stroke subtypes were included in this study. Mendelian randomization (MR) and multivariable MR (MVMR) analysis were performed to assess the causal associations between H. pylori antibodies and the development of stroke and to determine the potential mechanisms underlying the associations.

RESULTS

Genetically predicted serum H. pylori vacuolating cytotoxin-A (VacA) antibody level was associated with an increased risk of all-cause stroke (odds ratio [OR] = 1.04, 95% CI 1.01-1.07, P = 0.017) and cardioembolic stroke (CES, OR = 1.11, 95% CI 1.04-1.18, P = 0.001). The results of multivariable MR (MVMR) showed that C-reactive protein (CRP), but not monocyte chemoattractant protein-1 and peptic ulcer, mediated the causal effects of VacA-positive H. pylori infection on all-cause stroke and CES. No strong causal associations were found between other H. pylori antibodies and stroke and its subtypes.

CONCLUSIONS

Our results demonstrate that H. pylori VacA antibody is the only causal determinant associated with the risk of stroke in the spectrum of H. pylori-related antibodies, in which CRP may mediate the association. This study suggests that inhibition of the CRP signaling pathway may reduce the risk of stroke in patients with VacA-positive H. pylori infection.

Helicobacter pylori-Related Extraintestinal Manifestations—Myth or Reality

It is well documented that Helicobacter pylori (H. pylori) can cause both gastrointestinal and extraintestinal manifestations. The latter one represents a major burden in terms of diagnosis and treatment. H. pylori-associated systemic subclinical inflammation is mostly responsible for the development of extraintestinal manifestations, and its early eradication might result in preventing all adverse events related to their occurrence. Thus, it was suggested that H. pylori might be associated with iron deficiency anemia, thrombocytopenia (immune thrombocytopenic purpura), Schonlein Henoch purpura, failure to thrive, vitamin B12 deficiency, diabetes mellitus, body mass index, cardiovascular diseases, as well as certain neurological conditions. Nevertheless, studies showed both pros and cons in terms of the role of H. pylori in the development of previously mentioned clinical entity underlining the crucial need for further studies on these topics. Although most of these extraintestinal manifestations occur during adulthood, we must not forget that H. pylori infection is acquired mainly during childhood, and thus its early diagnosis and eradication might represent the cornerstone in the prevention of H. pylori-induced inflammatory status and consequently of all related extraintestinal conditions.

Helicobacter pylori Infection Is Associated With Carotid Intima and Media Thickening: A Systematic Review and Meta-Analysis

Background

Helicobacter pylori (H. pylori) infection affects ≈4.4 billion people worldwide. Several studies suggest that this pathogen impacts the digestive system, causing diverse and severe conditions, and results in extragastrointestinal disorders like vascular diseases. Our study aims to examine the association between H. pylori infection and carotid intima‐media thickness.

Methods and Results

Electronic databases (MEDLINE, Embase, CENTRAL, Web of Science, and Scopus) were searched for studies, comparing the thickness of the carotid intima‐media in H. pylori–infected and noninfected individuals listed until October 20, 2020. Statistical analyses were performed using the random effects meta‐analysis of model of weighted mean differences with the corresponding 95% CI using the DerSimonian and Laird method. The protocol was registered in advance in PROSPERO (International Prospective Register of Systematic Reviews; CRD42021224485). Thirteen studies were found meeting inclusion criteria for our systematic review and meta‐analysis, presenting data on the thickness of the carotid intima‐media considering the presence of H. pylori infection. Altogether, 2298 individuals’ data were included (1360 H. pylori positive, 938 negative). The overall carotid intima‐media thickness was significantly larger among infected patients compared with uninfected participants (weighted mean difference: 0.07 mm; 95% CI, 0.02–0.12; P=0.004; I²=91.1%; P<0.001). In case of the right common carotid artery, the intima‐media thickening was found to be significant as well (weighted mean difference, 0.08 mm; 95% CI, 0.02–0.13, P=0.007; I²=85.1%; P<0.001), while it showed no significance in the left common carotid artery (weighted mean difference, 0.12 mm; 95% CI, −0.05 to 0.28, P=0.176; I²=97.4%; P<0.001).

Conclusions

H. pylori infection is associated with increased carotid intima‐media thickness. Therefore, the infection may indirectly contribute to the development of major vascular events.

Helicobacter pylori Infection Acts as an Independent Risk Factor for Intracranial Atherosclerosis in Women Less Than 60 Years Old

Background: Studies show inconsistent results regarding the relationship between Helicobacter pylori (H. pylori) infection and stroke. The present study assessed a potential association between H. pylori infection and an important risk factor for stroke, intracranial atherosclerosis.

Methods: In total, 15,798 subjects with transcranial Doppler (TCD) and 13C-urea breath test (13C-UBT) were enrolled from March 2012 to March 2017. Intracranial atherosclerosis was further measured using intracranial carotid artery calcification (ICAC) on past or recent head CT, and 14,084 subjects were ultimately included in the study. Baseline demographics, atherosclerosis risk factors, and laboratory results were investigated. Since endothelial dysfunction is critical to the development of atherosclerosis, the role of H. pylori in migration, tube formation, and proliferation of human brain microvascular endothelial cells (HBMECs) was assessed in vitro.

Results: The intracranial atherosclerosis group had a higher proportion of women and a greater rate of H. pylori infection than those without intracranial atherosclerosis. H. pylori infection was significantly more common in women with intracranial atherosclerosis than males. In addition, the incidence of intracranial atherosclerosis was significantly higher in women with H. pylori infection than uninfected women (53.8 vs. 46.4%, p &lt; 0.001). In an adjusted model, H. pylori was shown to be an independent risk factor for intracranial atherosclerosis in women ≤ 60 years of age [odds ratio (OR) = 2.261, 95% CI = 1.839–2.780, p &lt; 0.001]. Serum exosomes from patients with H. pylori infection had significantly reduced brain endothelial cell migration, tube formation, and proliferation in vitro.

Conclusion:Helicobacter pylori infection may be an important independent risk factor for intracranial atherosclerosis in women ≤ 60 years of age.

Effect of <i>Helicobacter pylori</i> Treatment on Long-term Mortality in Patients with Hypertension

Background/Aims

A meta-analysis of randomized trials performed in healthy asymptomatic individuals suggested that overall mortality may increase after Helicobacter pylori eradication despite a significant decrease in the gastric cancer incidence and mortality rates. This retrospective population-based cohort study investigated if H. pylori treatment is associated with an increase in overall mortality in patients with hypertension.

Methods

From the database of the Korean National Health Insurance Sample Cohort, we selected 198,487 patients treated for hypertension between 2002 and 2010. Those who received H. pylori treatment (H. pylori treatment cohort, 5,541 patients) were matched to those who did not (nontreatment cohort, 11,082 patients) at the ratio of 1 to 2. The primary outcome was the risk of overall mortality. The secondary outcomes were the risks of mortality due to cardiovascular disease, cerebrovascular disease, and cancer. The outcomes were evaluated from 6 months after H. pylori treatment to December 2013. A Cox proportional hazard model was used to estimate the hazard ratios (HRs).

Results

During a median follow-up period of 4.8 years, death from any cause was reported in 4.1% of the patients in the H. pylori treatment cohort and 5.5% of the patients in the nontreatment cohort. The adjusted HR (aHR) for overall mortality in the H. pylori treatment cohort was 0.70 (95% confidence interval [CI], 0.60 to 0.82; p<0.001). With regard to cause-specific mortality, compared with the nontreatment cohort, the H. pylori treatment cohort had a lower risk of mortality due to cerebrovascular disease (aHR, 0.46; 95% CI, 0.26 to 0.81; p=0.007). The risks of mortality due to cancer and cardiovascular disease were not different between the cohorts.

Conclusions

H. pylori treatment is not associated with an increase in overall mortality in patients treated for hypertension.

Association between Helicobacter Pylori infection and stroke: a meta-analysis of 273,135 patients

BACKGROUND

Stroke stands among the most leading causes of mortality worldwide. Although modifiable risk factors for stroke have been identified, current risk factors do not sufficiently explain the risk in young patients. Previous studies have postulated an association between infection by Helicobacter pylori (HP) and stroke.

OBJECTIVE

To investigate the association between HP infection and stroke by using a systematic review and meta-analysis approach.

METHODS

Four electronic search engines/libraries were systematically searched for relevant observational studies. Studies were screened for eligibility and data were extracted. The odds ratio (OR) and 95% confidence interval (95% CI) were combined under the random-effect model. The protocol was registered in PROSPERO (CRD42019123689).

RESULTS

Among the included studies, 25 studies were analyzed for anti-HP IgG, 9 studies were for anti-Cag A, and 6 studies were for the C-urea breath test. The results showed that positive anti-HP IgG was significantly associated with an increased risk of stroke [OR (95% CI) = 1.43 (1.25-1.46)]. Similarly, both antiCag A and C-urea breath test were significantly associated with an increased risk of stroke with [OR (95% CI) = 1.77 (1.25-2.49)], and [OR (95% CI) = 2.21 (1.33-3.66)], respectively. Furthermore, our results indicated that positive anti-HP IgG was associated with stroke caused by atherothrombosis and small artery disease.

CONCLUSIONS

This study suggests that HP infection is significantly associated with increased risk of stroke. However, more well-designed studies are required to investigate if early HP eradication might decrease the incidence of stroke.

Role of Helicobacter pylori infection in the manifestation of old age-related diseases

Helicobacter pylori is one of the most prevalent infection worldwide. It affects individuals of different age groups. Elderly people tend to resist eradication treatment and worsening of infection can lead to several gastric and non-gastric pathologies. Aging-associated cellular and molecular alteration can increase the risk of other pathologies such as osteoporosis, Alzheimer's disease, Parkinson's disease, respiratory and renal dysfunction, and cancer in geriatric patients, more than other age groups. This review article highlights some of the most common old age diseases and the role of H. pylori infection as a risk factor to worsen the conditions, presented by the molecular evidences of these associations. These studies can help clinicians to understand the underlying pathogenesis of the disease and identify high-risk patients, aiding clearer diagnosis and treatment.

Association between H. pylori infection and health Outcomes: an umbrella review of systematic reviews and meta-analyses

OBJECTIVE

Systematic reviews and meta-analyses have revealed the associations between H. pylori infection and various health outcomes. We aimed to evaluate the strength and breadth of evidence on the associations.

DESIGN

Umbrella review of systematic reviews and meta-analyses.

SETTING

No settings.

PARTICIPANTS

No patients involved.

DATA SOURCES

Embase, PubMed, Web of Science, Cochrane Library Databases, CNKI, VIP database and Wangfang database from inception to February 1, 2019.

OUTCOMES MEASURES

Diverse diseases (such as cancer and ischaemic heart disease).

RESULTS

Sixty articles reporting 88 unique outcomes met the eligible criteria. 74 unique outcomes had nominal significance (p<0.05). Of the outcomes with significance, 61 had harmful associations and 13 had beneficial associations. Furthermore, 73% (64) of the outcomes exhibited significant heterogeneity . Of the these meta-analyses, 32 had moderate to high heterogeneity (I²=50%-75%) and 24 had high heterogeneity (I²>75%). Moreover, 20% exhibited publication bias (p<0.1). In addition, 97% of the methodological qualities were rated 'critically low'. 36% of the evidence qualities of outcomes were rated 'low', 56% of the evidence qualities were rated 'very low' and 8% of the evidence qualities were rated 'moderate'. H. pylori infection may be associated with an increased risk of five diseases and a decreased risk of irritable bowel syndrome.

CONCLUSION

Although 60 meta-analyses explored 88 unique outcomes, moderate quality evidence only existed for six outcomes with statistical significance. H. pylori infection may be associated with a decreased risk of irritable bowel syndrome and an increased risk of hypertriglyceridemia, chronic cholecystitis and cholelithiasis, gestational diabetes mellitus, gastric cancer and systemic sclerosis.

TRIAL REGISTRATION

CRD42019124680.

Hellenic consensus on Helicobacter pylori infection

The Hellenic Society of Gastroenterology recently organized the “Hellenic consensus on Helicobacter pylori (H. pylori) infection”. The aim of this publication is to report the guidelines in order to aid the national gastroenterology community in the management of H. pylori infection. Forty-one delegates from all Greek regions, including gastroenterologists, pathologists, clinical microbiologists, epidemiologists and basic scientists, were invited to this meeting. The participants were allocated to 1 of the 4 main topics of the meeting: i.e., H. pylori diagnosis and association with diseases; H. pylori and gastric cancer; H. pylori and extragastric associated disorders; and H. pylori treatment. The results of each subgroup were submitted to a final consensus vote that included all participants. Relevant data based on international and Greek publications were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. The cutoff level of 70% was considered as acceptance for the final statement. It is hoped that the recommendations and conclusions of this report will guide Greek doctors in their daily practice concerning the management of H. pylori infection.

Helicobacter pylori, Vascular Risk Factors and Cognition in U.S. Older Adults

Previous studies suggested that Helicobacter pylori infection could be a risk factor for stroke, dementia, and Alzheimer's disease (AD). The authors examined data from participants, 60 years old and older in the Third National Health and Nutrition Examination Survey (NHANES-III) to assess the relation between Helicobacter pylori infection and results of the Mini-Mental State Examination (n = 1860) using logistic regression analysis controlling for age, gender, race/ethnicity, education, poverty and history of medically diagnosed diabetes. Moreover, we examined performance on the digit-symbol substitution test (DSST) of 1031 participants in the 1999-2000 NHANES according to their H. pylori infection status controlling for potential confounders using multiple linear regression analyses. In 1988-1991, older adults infected with CagA strains of H. pylori had a 50% borderline statistically significant increased level of cognitive impairment, as measured by low Mini-Mental State Examination (MMSE) scores (age-education adjusted prevalence ratio: 1.5; 95% confidence interval: 1.0, 2.0). In 1999-2000, older US adults infected with H. pylori scored 2.6 fewer points in the DSST than those uninfected (mean adjusted difference: -2.6; 95% confidence interval -5.1, -0.1). The authors concluded that H. pylori infection might be a risk factor for cognitive decline in the elderly. They also found that low cobalamin and elevated homocysteine were associated with cognitive impairment.

Ischemic stroke and infectious diseases in low-income and middle-income countries

PURPOSE OF REVIEW

To address the important relationships between stroke and infection, focusing on the most frequent infections found in low-income and middle-income countries.

RECENT FINDINGS

Stroke is one of the leading causes of mortality and disability worldwide, with a great proportion of the stroke burden occurring in low-income and middle-income countries. Infectious diseases are still a great health problem in developing countries and it is possible that the proportion of infection-related strokes is greater in these nations. Infectious diseases and stroke have a bidirectional relationship. Common infections may act as risk factors and can trigger stroke through different mechanisms in their acute phase. Several intracranial and systemic infections can cause stroke as a direct complication, such as Chagas disease, neurosyphilis, tuberculous meningitis, and neurocysticercosis. These conditions are of particular interest to low-income and middle-income countries, but also relevant to high-income nations because of increasing migration. Finally, infection is a frequent poststroke complication, with great impact in the patient outcome.

SUMMARY

Infectious diseases and stroke are common problems in low-income and middle-income countries. More studies are necessary to fully elucidate the real impact of infectious diseases on stroke burden, especially in countries where epidemiological data are still scarce.

Helicobacter pylori infection and prevalence of stroke

BACKGROUND

Helicobacter pylori causes peptic ulcer disease; however, conflicting evidence exists regarding its role in extragastric conditions. We aimed to examine associations of H pylori infection and peptic ulcer disease with stroke.

METHODS

A cross-sectional study was undertaken using data of 147 936 individuals aged 25-95 years who underwent the urea breath test during 2002-2012, based on the computerized database of the second largest health maintenance organization in Israel. Logistic regression models were fitted to control for potential confounders.

RESULTS

Overall, 1397 (0.9%) patients had stroke and 76 965 (52.0%) had a H pylori positive test. The likelihood of prevalent stroke increased in relation to H pylori infection: adjusted odds ratio (aOR) 1.16 (95% confidence intervals [CI]: 1.04-1.29), gastric ulcer: aOR 1.50 (95% CI: 1.18-1.91), and duodenal ulcer: aOR 1.25 (95% CI: 1.07-1.46).

CONCLUSIONS

The results support the premise that stroke may be associated with a history of H pylori infection.

Environmental Risk Factors for Stroke and Cardiovascular Disease

Besides the classical individual stroke risk factors a new class has appeared, the environmental risk factors. After a review of the evidences demonstrating that air pollution is a potent risk factor (Part 1), we propose an update of other physical, chemical, and biological factors, now considered as risk factors (Part 2). One of the challenges is to precise their specific roles as they can be combined in their noxious impacts (traffic air pollution + noise + weather + infections). This knowledge has practical consequences; From now on, medical advices cannot be limited to individual recommendations but must also deal with environmental public health issues.

Viral and parasitic pathogen burden and the association with stroke in a population-based cohort

Background Higher cumulative burden of viral and bacterial pathogens may increase the risk of stroke, but the contribution of parasitic infections in relation to cumulative pathogen burden and risk of stroke has rarely been examined. Aim To estimate the association of multiple persistent viral and parasitic infections with stroke in a representative sample of adults in the United States. Methods Serological evidence of prior infection was categorized as positive for 0-1, 2, 3, or 4-5 infections based on immunoglobulin G seropositivity to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. in 13,904 respondents from the National Health and Nutrition Examination Survey III. Regression analysis was used to estimate the cross-sectional association between serological evidence of prior infection and history of stroke adjusting for demographic risk factors, and potential mediators of stroke. Results Age-adjusted models that included serological evidence of prior infection to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. showed that adults in the highest serological evidence of prior infection category (4-5 infections) had a higher prevalence of stroke (5.50%, 95% confidence interval 2.44-10.46%) than those in the lowest serological evidence of prior infection categories (1.49%, 95% confidence interval 1.01-2.11%), and a trend test suggested a graded association between serological evidence of prior infection and stroke ( p = 0.02). In multivariable logistic regression models, the positive association of serological evidence of prior infection with stroke prevalence remained significant after adjustment for other significant risk factors (odds ratio = 1.4, p = 0.01) but was only significant among those aged 20-59 (odds ratio = 2.0, p = 0.005) and not among those aged 60-69 ( p = 0.78) or 70 and older ( p = 0.43). Conclusion We found support for a connection between serological evidence of prior infection to cytomegalovirus, hepatitis A virus, hepatitis B virus, Toxoplasma gondii, and Toxocara spp. and stroke among those aged 20-59. There may be a need to consider common parasitic infections in addition to viral and bacterial pathogens when calculating serological evidence of prior infection in relation to cerebrovascular disease.

幽门螺杆菌感染与心血管疾病

随着社会经济的发展与生活方式的改变, 心血管疾病的发生率明显上升, 相关的危险因素包括年龄、吸烟、肥胖、糖尿病、高血压和血脂异常等, 但仍有一部分心血管疾病尚未发现确切病因. 近年来, 随着幽门螺杆菌(Helicobacter pylori, H. pylori)研究的不断深入, 发现其与多种胃肠外疾病的发生发展密切相关. 目前国内外多项研究探讨了H. pylori感染与心血管疾病的相关性, 多数研究认为心血管疾病患者H. pylori感染率明显增加, 联合H. pylori根除治疗有益于心血管疾病的防治, 但也有结果并不完全一致. 本文就心血管疾病中H. pylori感染的研究现状, 根除H. pylori对心血管疾病的影响以及H. pylori感染诱导心血管疾病的机制等方面的相关研究作一综述.

A meta-analysis of stroke risk following herpes zoster infection

Background

The incidence of herpes zoster (HZ) is increasing and poses a significant health concern to aging populations. Several studies suggest an increased risk of stroke following zoster infection, but the results are conflicting. We conducted a systematic review and meta-analysis to determine if stroke risk is increased following HZ infection.

Methods

A search of MEDLINE, EMBASE, Google scholar, Web of Science, CAB Direct, Cumulative Index to Nursing and Allied Health Literature, and Evidence Based Medicine Reviews was conducted for observational studies of adults with HZ infection that examined stroke and TIA risk from January 1, 1966 to May 31, 2016. Adjusted relative risks reported for similar follow-up durations were pooled across studies separately using random-effects inverse variance models.

Results

Data were pooled from nine studies. Relative risk for stroke after zoster was 1.78 (95% CI 1.70–1.88) for the first month following herpes zoster, dropping progressively to 1.43 (95% CI 1.38–1.47) after 3 months, to 1.20 (95% CI 1.14–1.26) after 1 year. We found that stroke risk increases by a larger margin during the first month after a herpes zoster ophthalmicus episode: relative risk 2.05 (95% CI 1.82–2.31). The risk remains elevated one year after the acute episode.

Conclusions

Herpes zoster is an established risk factor for increasing the risk of stroke, especially shortly after infection. Vaccination should be encouraged in patients at high risk of cardiovascular disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2278-z) contains supplementary material, which is available to authorized users.

Association between Helicobacter pylori infection and angiographically demonstrated coronary artery disease: A meta-analysis

Coronary artery disease (CAD) is a leading cause of mortality globally. However, the etiology and pathogenesis of CAD are not fully understood. The aim of the present meta-analysis was to estimate the association between the risk of CAD and Helicobacter pylori (H. pylori) infection. A literature search was performed to identify eligible studies published prior to August 14, 2014. Fixed or random effect meta-analytical methods were used to pool the data and perform the subgroup analyses. The effect measures estimated were the odds ratios (OR) for dichotomous data reported with 95% confidence intervals (95% CI). Of the 109 studies identified using the search parameters, 26 cross-sectional studies were eligible involving 3,901 CAD patients and 2,751 controls. H. pylori infection was associated with an increased risk of CAD (OR: 1.96, 95% CI: 1.47-2.63, P<0.00001). When the adjusted ORs were used to conduct another meta-analysis, the OR value decreased, but the association remained significant (OR: 1.42, 95% CI: 1.09-1.86, P=0.008). The association between H. pylori infection and CAD risk was stronger in younger individuals than in older individuals (OR: 2.36, 95% CI 1.50-3.73 vs. OR: 1.59, 95% CI: 1.19-2.11). A significant association was observed in studies from Europe (OR: 2.11, 95% CI: 1.54-2.88, P=0.01) and the USA (OR: 1.43, 95% CI: 1.08-1.91, P=0.36). There is a potential association between H. pylori infection and the risk of CAD. The association may be influenced by age and ethnicity.

Development of a liquid formulation of poorly water-soluble isosteviol sodium using the co-solvent technology

An intravenously injectable liquid formulation of the poorly water-soluble isosteviol sodium (ISVNa) that has a great clinical potential for cardiovascular diseases was developed using the co-solvent technology. The pH and composition of the co-solvent were optimized to obtain a stable liquid formulation (termed as STVNa) based on saline at pH 10.0 containing 25% (v/v) of ethanol and 20% (v/v) of propylene glycol. STVNa was physicochemically stable upon storage for more than 3 months under various conditions. In vitro studies showed that STVNa did not induce hemolytic effects up to 9.1% (v/v) after 3 h of incubation and it was cytocompatible up to 50 μg/mL in H2C9 cells. Furthermore, STVNa showed acceptable safety and pharmacokinetic parameters comparable with those of ISVNa in saline (dissolved at 60 °C) upon i.v. injection in Wistar rats. Overall, the results demonstrated that STVNa is a promising formulation of ISVNa for clinical translation.

Association between Helicobacter pylori Infection and Cerebral Small Vessel Disease

Background

Small vessel disease is an important cause of cerebrovascular diseases and cognitive impairment in the elderly. There have been conflicting results regarding the relationship between Helicobacter pylori infection and ischemic stroke. This study aimed to examine the association between H. pylori infection and cerebral small vessel disease.

Methods

The study included 1,117 patients who underwent brain magnetic resonance imaging and H. pylori identification between 2005 and 2013 at Health Promotion Center, Seoul National University Hospital. Multivariable logistic regression analysis was used to assess the association between H. pylori infection and small vessel disease with adjustment for age, sex, hypertension, diabetes mellitus, dyslipidemia, body mass index, smoking status, problem drinking, and antiplatelet use.

Results

The adjusted odds ratios (aORs) for the association between H. pylori infection and silent brain infarction and cerebral microbleeds were 1.03 (95% confidence interval [CI], 0.66-1.61) and 0.70 (95% CI, 0.38-1.28), respectively. The aORs for silent brain infarction and cerebral microbleeds were 0.81 (95% CI, 0.44-1.44) and 0.59 (95% CI, 0.30-1.18) in patients aged <65 years and 1.59 (95% CI, 0.78-3.22) and 1.89 (95% CI, 0.38-9.33) in those aged >65 years, respectively. Moreover, the aORs for silent brain infarction and cerebral microbleeds were 0.96 (95% CI, 0.54-1.71) and 0.74 (95% CI, 0.33-1.69) in H. pylori-infected patients without atrophic gastritis and 0.89 (95% CI, 0.48-1.62) and 0.99 (95% CI, 0.43-2.27) in those with atrophic gastritis, respectively.

Conclusion

No association between H. pylori infection and small vessel disease was observed. H. pylori-induced inflammation may not be a risk factor for microcirculatory damage in the brain.

Extragastric Diseases and Helicobacter pylori

The extragastric manifestations of Helicobacter pylori infection still remain a very strong topic throughout the H. pylori world. Indeed, H. pylori may interfere with many biological processes, both inside and outside of the stomach, possibly influencing or determining the occurrence of many diseases outside of the stomach. While its role in idiopathic thrombocytopenic purpura and sideropenic anemia has already been recognized, emerging evidence suggests that H. pylori may increase the risk of acute coronary syndrome, contribute to insulin resistance and be associated with neurodegenerative, respiratory, and other miscellaneous disorders previously associated with other conditions. Different pathogenic mechanisms have been hypothesized, including the induction of a low-grade inflammatory state and the occurrence of molecular mimicry mechanisms. This review summarizes the results of the most relevant studies published on this topic in the last year.

Peripheral to central: Organ interactions in stroke pathophysiology

Stroke is associated with a high risk of disability and mortality, and with the exception of recombinant tissue-type plasminogen activator for acute stroke, most treatments have proven ineffective. Clinical translation of promising experimental therapeutics is limited by inadequate stroke models and a lack of understanding of the mechanisms underlying acute stroke and how they affect outcome. Bidirectional communication between the ischemic brain and peripheral immune system modulates stroke progression and tissue repair, while epidemiological studies have provided evidence of an association between organ dysfunction and stroke risk. This crosstalk can determine the fate of stroke patients and must be taken into consideration when investigating the pathophysiological mechanisms and therapeutic options for stroke. This review summarizes the current evidence for interactions between the brain and other organs in stroke pathophysiology in basic and clinic studies, and discusses the role of these interactions in the progression and outcome of stroke and how they can direct the development of more effective treatment strategies.

Helicobacter pylori: Does it add to risk of coronary artery disease

Helicobacter pylori (H. pylori) is a known pathogen implicated in genesis of gastritis, peptic ulcer disease, gastric carcinoma and gastric lymphoma. Beyond the stomach, the organism has also been implicated in the causation of immune thrombocytopenia and iron deficiency anemia. Although an area of active clinical research, the role of this gram negative organism in causation of atherosclerosis and coronary artery disease (CAD) remains enigmatic. CAD is a multifactorial disease which results from the atherosclerosis involving coronary arteries. The major risk factors include age, diabetes mellitus, smoking, hypertension and dyslipidemia. The risk of CAD is believed to increase with chronic inflammation. Various organisms like Chlamydia and Helicobacter have been suspected to have a role in genesis of atherosclerosis via causation of chronic inflammation. This paper focuses on available evidence to ascertain if the role of H. pylori in CAD causation has been proven beyond doubt and if eradication may reduce the risk of CAD or improve outcomes in these patients.