Influence of Helicobacter pylori infection and eradication on blood lipids and fibrinogen

The influence of Helicobacter pylori infection on acute coronary syndrome and lipid metabolism in the Chinese ethnicity

Background

Acute coronary syndrome (ACS) patients frequently present a relatively high prevalence of Helicobacter pylori (H. pylori) infection. H. pylori was previously hypothesized to induce ACS through the regulation of lipid levels. However, the risk of H. pylori-induced ACS varies significantly among different ethnic groups, and the associations between H. pylori and lipid parameters remain unclear. This study aimed to systematically assess the risk of ACS in Chinese populations with H. pylori infection while also evaluating the effects of H. pylori on lipid parameters.

Materials and methods

A hospital-based case-control study involving 280 participants was conducted. Immunoblotting was used for the detection and genotyping of H. pylori. The associations between H. pylori and ACS, as well as lipid parameters, were analyzed via the chi-square test and a multiple logistic regression model.

Results

H. pylori infection significantly increased the risk of ACS among all participants (adjusted odds ratio (OR) = 4.04, 95% confidence interval (CI): 1.76-9.25, P < 0.05), with no associations with virulence factors (cytotoxin-associated gene A (CagA) or vacuole toxin geneA (VacA)). Subgroup analysis revealed a significant increase in the risk of ACS among the elderly population aged 56-64 years with H. pylori infection. Additionally, a substantial association was observed between H. pylori and acute myocardial infarction (AMI). No significant differences were found in lipid parameters, including low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and the LDL/HDL ratio, between individuals positive and negative for H. pylori infection. Similar results were observed between the ACS group and the control group.

Conclusions

Our study has demonstrated for the first time that H. pylori does not significantly impact lipid metabolism but increases the risk of ACS fourfold in the Chinese population (OR = 4.04, 95% CI: 1.76-9.25). Furthermore, the virulence factors of H. pylori (CagA and VacA) may not be involved in the mechanisms by which they promote the development of ACS. This finding provides additional evidence for the association between H. pylori and ACS among different ethnic groups and refutes the biological mechanism by which H. pylori affects ACS through lipid metabolism regulation. Regular screening for H. pylori and eradication treatment in elderly individuals and those at high risk for ACS may be effective measures for reducing the incidence of ACS. Future research should include multicenter randomized controlled trials and explore host genetics and the effects of H. pylori on the gut microbiota as potential biological pathways linking H. pylori and ACS.

Traditional and nontraditional lipid parameters in Helicobacter pylori infection

Aims: This study sought to evaluate the relationship between Helicobacter pylori infection and traditional and nontraditional lipid parameters, including atherogenic index of plasma, cardiogenic risk ratio, atherogenic coefficient and remnant cholesterol. Methods: After the application of exclusion criteria, 309 patients were allocated according to the absence (n = 52) or presence (n = 257) of H. pylori infection. Results: Total cholesterol, low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) levels were nonsignificantly higher, and HDL-C levels were nonsignificantly lower, in the H. pylori-infected patient group. Triglyceride-to-HDL-C ratio, LDL-C-to-HDL-C ratio, atherogenic index of plasma, cardiogenic risk ratio, atherogenic coefficient and remnant cholesterol were comparable among groups. Conclusion: There was no significant association between H. pylori infection and traditional and nontraditional novel lipid parameters and indices.

Effect of Helicobacter Pylori Infection on Glucose Metabolism, Lipid Metabolism and Inflammatory Cytokines in Nonalcoholic Fatty Liver Disease Patients

Objective

To probe into the influence of Helicobacter pylori (Hp) infection on glucose metabolism, lipid metabolism, and inflammatory cytokines in patients with nonalcoholic fatty liver disease (MASLD).

Methods

A total of 140 MASLD patients admitted to our Hospital between June 2020 and May 2021 were selected as the research objects. Based on the presence or absence of Hp infection, they were divided into the study group (73 cases with infection) and control group (67 cases without infection). Glucose metabolism indicators [fasting blood glucose (FBG), 2-hour postprandial glucose (2hPG), fasting insulin (FINS), glycated hemoglobin (HbAlc)], lipid metabolism indicators [total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C)], and inflammatory indicators [interleukin-37 (IL-37), interleukin-18 (IL-18)] were measured and compared between the two groups.

Results

In terms of glucose metabolism indicators, the study group exhibited higher levels of FBG (5.84±0.49 vs 5.40±0.51, t=2.535, P=0.012), 2hPG (7.26±1.30 vs 6.50±1.53, t=3.321, P<0.001), and FINS (11.13±4.13 vs 9.12±3.72, t=3.224, P<0.001), and Insulin resistance index (HOMA-IR) (2.97±0.35 VS 2.13±0.54, t=3.761, P<0.001) and a lower level of HbAlc (5.25±0.56 vs 6.12±0.57, t=5.473, P<0.001) compared to the control group. Regarding lipid metabolism indicators, the study group exhibited higher levels of TC (5.64±1.49 vs 5.01±1.32, t=3.332, P<0.001), TG (1.89±0.34 vs 1.32±0.43, t=3.411, P<0.001), and LDL-C (3.31±0.43 vs 2.12±0.29, t=4.142, P<0.001), and a lower level of HDL-C (1.45±0.21 vs 1.78±0.42, t=4.347, P<0.001) compared to the control group. As for the inflammatory indicators, the study group exhibited higher levels of IL-37 (45.56±6.02 vs 34.02±3.28, t=9.332, P<0.001) and IL-18 (73.57±5.82 vs 60.34±4.84, t=10.141, P<0.001) compared to the control group.

Conclusion

It is crucial to place appropriate emphasis on the impact of Hp infection on the glucose metabolism, lipid metabolism, and inflammatory response in MASLD patients, warranting careful consideration during the treatment of these patients.

The causal effect of Helicobacter pylori infection on coronary heart disease is mediated by the body mass index: a Mendelian randomization study

The association between Helicobacter pylori (H. pylori) infection and coronary heart disease (CHD) remains controversial, with an unclear causal link. This study employed bidirectional Mendelian randomization (MR) method, using H. pylori infection as the exposure, to investigate its causal relationship with CHD diagnosis, prognosis, and potential pathogenesis. H. pylori infection exhibited a causal association with body mass index (BMI) (β = 0.022; 95% CI 0.008-0.036; p = 0.001). Conversely, there was no discernible connection between H. pylori infection and the diagnosis of CHD (OR = 0.991; 95% CI 0.904-1.078; p = 0.842; IEU database; OR = 1.049; 95% CI 0.980-1.118; p = 0.178; FinnGen database) or CHD prognosis (OR = 0.999; 95% CI 0.997-1.001; p = 0.391; IEU database; OR = 1.022; 95% CI 0.922-1.123; p = 0.663; FinnGen database). Reverse MR analysis showed no causal effect of CHD on H. pylori infection. Our findings further support that H. pylori infection exerts a causal effect on CHD incidence, mediated by BMI. Consequently, eradicating or preventing H. pylori infection may provide an indirect clinical benefit for patients with CHD.

Association between Helicobacter pylori infection and metabolic syndrome and its components

Background and aim

The association between Helicobacter pylori (H. pylori) infection and metabolic syndrome (MetS) has been studied previously; however, the results remain controversial, which could be partly due to the different criteria used for defining MetS. We adopted five MetS criteria to provide better understanding of the association between H. pylori infection and MetS.

Methods

Physical examination data of 100,708 subjects were obtained from January 2014 to December 2018. MetS was defined based on five criteria including: International Diabetes Federation (IDF), The Third Report of the National Cholesterol Education Program Expert Panel, Adult Treatment Panel III (ATP III), Joint Statement of International Multi-Societies (JIS), Chinese Diabetes Society (CDS), and the Guidelines for the Prevention and Treatment of Type 2 Diabetes in China (2017 edition)(CDS DM). Multivariate logistic regression analysis was performed to elucidate the association between H. pylori infection and MetS and its components.

Results

The prevalence of MetS defined assessed using IDF, ATP III, JIS, CDS and CDS DM criteria was 15.8%, 19.9%, 23.7%, 8.7% and 15.4%, respectively. In males, the prevalence of MetS assessed using the five criteria in H. pylori-positive group was higher than that in negative-group; however, in females, same results were obtained using the three international criteria. In males, the prevalence of all MetS components was found to be higher in the H. pylori-positive group than those in the negative group; however, in females, only the prevalence of dyslipidemia and waist circumferences exhibited significant differences. Multivariate logistic regression analysis revealed that H. pylori infection in males was positively correlated with MetS. Additionally, H. pylori infection was found to be positively correlated with the waist circumference in the general population, and with hypertension and hyperglycemia in males.

Conclusions

H. pylori infection was found to be positively associated with MetS in males in China.

No evidence for a causal link between Helicobacter pylori infection and nonalcoholic fatty liver disease: A bidirectional Mendelian randomization study

Although clinical studies have shown the possible relationship between Helicobacter pylori (H. pylori) infection and the development of nonalcoholic fatty liver disease (NAFLD), their causal relationship is still unknown. This bidirectional Mendelian randomization (MR) study aimed to investigate the causal link between H. pylori infection and NAFLD. Two previously reported genetic variants SNPs rs10004195 and rs368433 were used as the instrumental variables (IVs) of H. pylori infection. The genetic variants of NAFLD were extracted from the largest genome-wide association study (GWAS) summary data with 1,483 cases and 17,781 controls. The exposure and outcome data were obtained from the publicly available GWAS dataset. Then, a bidirectional MR was carried out to evaluate the causal relationship between H. pylori infection and NAFLD. In addition, the GWAS data were also collected to explore the causal relationship between H. pylori infection and relevant clinical traits of NAFLD, including triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), and body mass index (BMI). Genetically predicted H. pylori infection showed no association with NAFLD both in FinnGen GWAS (OR, 1.048; 95% CI, 0.778-1.411; value of p = 0.759) and the GWAS conducted by Anstee (OR, 0.775; 95% CI, 0.475-1.265; value of p = 0.308). An inverse MR showed no causal effect of NAFLD on H. pylori infection (OR,0.978;95% CI, 0.909-1.052; value of p = 0.543). No significant associations were observed between H. pylori infection and the levels of triglycerides, LDL-C, HDL-C, or FBG, while H. pylori infection was associated with an increase in BMI. These results indicated that there was no genetic evidence for a causal link between H. pylori and NAFLD, suggesting that the eradication or prevention of H. pylori infection might not benefit NAFLD and vice versa.

The association of Helicobacter Pylori infection with dyslipidaemia and other atherogenic factors in dyspeptic patients at St. Paul's Hospital Millennium Medical College

Background

Studies showed that more than half of Ethiopians were presumed to be chronically infected with H. pylori. Nowadays, evidence has come to the literature strongly suggesting the potential association between H. pylori and extra gastric disorders including atherosclerosis.

Objective

To assess the association of helicobacter pylori infection with dyslipidaemia and other atherogenic factors in dyspeptic patients at St. Paul's Hospital Millennium Medical College, from November 2019 to June 2020.

Materials and methods

This institution-based cross-sectional study was examining 346 dyspeptic patients at SPHMMC from November 2019 to June 2020. A structured questionnaire was used to collect socio-demography data and anthropometric measurement was taken. Biochemical parameters were measured in serum samples by using Cobas 6000 clinical chemistry analyzer. Data were coded and entered into a statistical package for social sciences (SPSS) version 23 for analysis. Risk factors were identified using logistic regression. Hence, a bivariate logistic regression analysis test was conducted and variables with a p < 0.25 were included in the multivariate logistic regression model. P-values ≤0.05 were considered as a cut point for statistical significance in the final model.

Results

An overall prevalence of dyslipidemia among study participants was 253 (73.12 %). Among those who tested positive for H. pylori, 119/174 (68.39 %) had dyslipidemia in at least one lipid profile, while 8 (4.60%) had dyslipidemia in all four lipid profiles. After adjusting for traditional dyslipidemia risk factors, age >45 (AOR 4.864, 95% CI 2.281-4.080, P < 0.001), systolic blood pressure >120mmHg (AOR 1.036, 95% CI 1.009-1.065, P = 0.036) and being H. Pylori seropositive (AOR 0.555, 95% CI 0.318-0.967, P = 0.038) were an independent predictors of dyslipidemia.

Conclusion

This study reported that more than two-thirds of the H. pylori seropositive groups had exhibited dyslipidemia in at least one lipid profile, which can accelerate the incidence of atherosclerosis process.

Relationship Between Helicobacter pylori Infection and Arteriosclerosis

It is reported that Helicobacter pylori (H. pylori) infection may be linked to non-digestive tract diseases, such as arteriosclerosis including dyslipidemia, diabetes, obesity, hypertension, and cardiovascular disease. Therefore, we reviewed recent studies available in PubMed dealing with the mechanisms of arteriosclerosis due to H. pylori infection and the effects of H. pylori eradication. Conventional studies suggested that H. pylori infection may increase the risk of arteriosclerosis. A large interventional study is required to clarify the causal relationships and the effects of bacterial eradication.

The Effect of Helicobacter pylori Eradication on Lipid Levels: A Meta-Analysis

Introduction:Helicobacter pylori (H. pylori) infection is positively associated with cardiovascular diseases, but the involvement of lipids in this association remains unclear. The present study reviewed the changes in circulating lipid levels following H. pylori eradication. Methods: A PubMed database was searched until December 2020 to identify randomized control trials (RCTs) and non-RCTs investigating the effect of H. pylori eradication on the lipid levels in inverse variance-weighted, random-effects meta-analyses. Results: A total of 24 studies (four RCTs and 20 non-RCTs) with 5270 participants were identified. The post-eradication levels were increased for high-density lipoprotein cholesterol (HDL-C; mean difference (MD) 2.28 mg/dL, 95% confidence interval (CI) 1.90 to 2.66) and triglyceride (TG; MD 3.22 mg/dL, 95% CI 1.13 to 5.31) compared with the pre-eradication levels. H. pylori eradication resulted in little to no difference in the low-density lipoprotein-cholesterol levels (MD −2.33 mg/dL, 95% CI −4.92 to 0.26). In the analyses of RCTs only, the findings for elevated HDL-C levels, but not TG, were robust. Conclusions:H. pylori eradication increases the HDL-C levels. Further studies are needed to elucidate the effects of lipid changes following H. pylori eradication on cardiovascular diseases.

Gut Microbiota: The Missing Link Between Helicobacter pylori Infection and Metabolic Disorders?

Helicobacter pylori (H. pylori) is a gram-negative bacterium that infects approximately 4.4 billion individuals worldwide. Although the majority of infected individuals remain asymptomatic, this bacterium colonizes the gastric mucosa causing the development of various clinical conditions as peptic ulcers, chronic gastritis and gastric adenocarcinomas and mucosa-associated lymphoid tissue lymphomas, but complications are not limited to gastric ones. Extradigestive pathologies, including metabolic disturbances such as diabetes, obesity and nonalcoholic fatty liver disease, have also been associated with H. pylori infection. However, the underlying mechanisms connecting H. pylori with extragastric metabolic diseases needs to be clarified. Notably, the latest studies on the topic have confirmed that H. pylori infection modulates gut microbiota in humans. Damage in the gut bacterial community (dysbiosis) has been widely related to metabolic dysregulation by affecting adiposity, host energy balance, carbohydrate metabolism, and hormonal modulation, among others. Taking into account that Type 2 diabetic patients are more prone to be H. pylori positive, gut microbiota emerges as putative key factor responsible for this interaction. In this regard, the therapy of choice for H. pylori eradication, based on proton pump inhibitor combined with two or more antibiotics, also alters gut microbiota composition, but consequences on metabolic health of the patients has been scarcely explored. Recent studies from our group showed that, despite decreasing gut bacterial diversity, conventional H. pylori eradication therapy is related to positive changes in glucose and lipid profiles. The mechanistic insights explaining these effects should also be addressed in future research. This review will deal with the role of gut microbiota as the linking factor between H. pylori infection and metabolic diseases, and discussed the impact that gut bacterial modulation by H. pylori eradication treatment can also have in host's metabolism. For this purpose, new evidence from the latest human studies published in more recent years will be analyzed.

Both diet and Helicobacter pylori infection contribute to atherosclerosis in pre- and postmenopausal cynomolgus monkeys

A number of viruses and bacterial species have been implicated as contributors to atherosclerosis, potentially providing novel pathways for prevention. Epidemiological studies examining the association between Helicobacter pylori and cardiovascular disease have yielded variable results and no studies have been conducted in nonhuman primates. In this investigation, we examined the relationship between H. pylori infection and atherosclerosis development in socially housed, pre- and postmenopausal cynomolgus macaques consuming human-like diets. Ninety-four premenopausal cynomolgus monkeys (Macaca fascicularis) were fed for 36 months an atherogenic diet deriving its protein from either casein lactalbumin(CL) or high isoflavone soy (SOY). Animals were then ovariectomized and fed either the same or the alternate diet for an additional 36 months. Iliac artery biopsies were obtained at the time of ovariectomy and iliac and coronary artery sections were examined at the end of the study. Evidence of H. pylori infection was found in 64% of the monkeys and 46% of animals had live H. pylori within coronary atheromas as determined by mRNA-specific in situ hybridization. There was a significant linear relationship between the densities of gastric and atheroma organisms. Helicobactor pylori infection correlated with increased intimal plaque area and thickness at both the premenopausal and postmenopausal time points and regardless of diet (p< 0.01), although animals consuming the SOY diet throughout had the least amount of atherosclerosis. Additionally, plasma lipid profiles, intimal collagen accumulation, ICAM-1, and plaque macrophage densities were adversely affected by H. pylori infection among animals consuming the CL diet, while the SOY diet had the opposite effect. Plaque measurements were more highly associated with the densities of cagA-positive H. pylori within coronary atheromas than with the densities of gastric organisms, whereas plasma lipid changes were associated with H. pylori infection, but not cagA status. This study provides strong evidence that live H. pylori infects atheromas, exacerbates atherosclerotic plaque development, and alters plasma lipid profiles independently of diet or hormonal status. Finally, socially subordinate animals relative to their dominant counterparts had a greater prevalence of H. pylori, suggesting a stress effect. The results indicate that early H. pylori eradication could prevent or delay development of cardiovascular disease.

Helicobacter pylori eradication increases the serum high density lipoprotein cholesterol level in the infected patients with chronic gastritis: A single-center observational study

Background

Extra-gastric manifestation of Helicobacter pylori infection involves systemic inflammation, which results in the production of several cytokines. Only a few clinical trials have investigated the effect of H. pylori eradication therapy on lipid metabolism in the infected patients with chronic gastritis. We aimed to evaluate the effect of H. pylori eradication therapy on lipid metabolism in a Japanese population with chronic gastritis.

Methods

One hundred and sixty-three patients with H. pylori-associated chronic gastritis were enrolled in this study between June 2015 and March 2017. They underwent H. pylori eradication therapy; the effects of the therapy were assessed by the urea breath test performed at least 4 weeks after the therapy. After confirming H. pylori eradication, the health screening examination was repeated between May 2016 and August 2018. The clinical parameters were compared before and after the administration of the eradication therapy.

Results

The mean age of the enrolled patients was 56.7 years, and the mean follow-up duration was 514.7 days. Weight, body mass index, and obesity index were significantly increased post-eradication therapy compared to those pre-eradication therapy. White blood cell and platelet counts were significantly decreased, and high density lipoprotein cholesterol (HDL) level was significantly increased (P = 0.001), while low density lipoprotein cholesterol (LDL), total cholesterol, and triglycerides levels were not altered significantly. Hence, the LDL/HDL ratio was significantly decreased.

Conclusions

This study reported that H. pylori eradication therapy increase the HDL levels in the infected patients with chronic gastritis. Hence, the LDL/HDL ratio, which is used to evaluate the risk of atherosclerosis, was significantly decreased post-eradication therapy compared to that pre-eradication therapy.

Helicobacter pylori infection as a risk factor for serum bilirubin change and less favourable lipid profiles: a hospital-based health examination survey

Background

Helicobacter pylori infection is associated with several extragastric conditions including dyslipidemia and metabolic syndrome. This study aimed to investigate additional metabolic parameters associated with H. pylori infection in a Chinese population.

Methods

Using a case-control approach we studied 617 subjects with ¹³C-urea breath test (¹³C-UBT) values ≥10‰ who were defined as being positive for H. pylori (cases), while 617 sex and age- matched subjects with ¹³C-UBT values ≤1‰ were defined as H. pylori negative (controls) in Beijing Tongren Hospital from March 2016 to May 2017. Biochemical parameters including serum bilirubin and lipids were tested.

Results

A total of 1982 subjects participated in this study. The H. pylori infected subjects had significantly lower serum direct bilirubin concentrations (2.34 ± 0.38 vs. 2.47 ± 0.90 μmol/L, P = 0.008). H. pylori infection was independently associated with lower direct bilirubin levels (OR = 1.497, 95% CI =1.121–1.999, P = 0.006) or total bilirubin levels (OR = 1.322, 95% CI =1.005–1.738, P = 0.046) after adjustment for age, sex, body mass index (BMI), alanine aminotransferase (ALT), aspartate aminotransferase (AST), high-density lipoprotein cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), total cholesterol (TC) and triglycerides(TG). In addition, the H. pylori infected subjects had higher LDL-C levels (2.98 ± 0.76 vs. 2.89 ± 0.75 mmol/L, P = 0.033) and lower HDL-C levels (1.39 ± 0.37 vs. 1.44 ± 0.41 mmol/L, P = 0.044). LDL-C was negatively correlated with direct bilirubin concentration (R = − 0.260, P < 0.0001).

Conclusions

Bilirubin has been found to be a potent endogenous antioxidant and negatively associated with metabolic syndrome. Our results suggest that H. pylori infection is an independent risk factor for serum bilirubin reduction and less favorable lipid profiles.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-3787-8) contains supplementary material, which is available to authorized users.

The effects of helicobacter pylori eradication on modification of metabolic syndrome parameters in patients with functional dyspepsia

BACKGROUND

Helicobactor pylori (H. pylori) have the potential role in the pathogenesis of various extra-gastric disorders such as metabolic disorders. But, it is now questioned about whether H. pylori eradication reduces or induces the risk for metabolic disorders especially in patients with dyspepsia. Hence, the present study aimed to assess the effects of H. pylori eradication on criteria of metabolic syndrome.

METHODS

H. pylori infected patients with dyspepsia were included. The patients were treated with omeprazole (20mg, q12h), amoxicillin (1g, q12h), and clarithromycin (500mg, q12h) for two weeks, then H. pylori eradication was evaluated by C¹⁴ Breathing test (UBT) 6 weeks after the end of the treatment. Demographic data, clinical manifestation and metabolic parameters were recorded before and three months after completing treatment regimen. The data was analyzed by SPSS version 16.0.

RESULTS

Of 110 patients were initially enrolled, 91 patients completed the study. Overall eradication rate was 61.5%. Significant differences in the serum level of total cholesterol(180.7±34 vs. 172.1±28, p=0.001), LDL(107.0±25 vs. 100.8±20, p<0.001), HDL(46.2±8.7 vs. 48.9±8.6, p<0.001), fasting blood sugar (93.7±12 vs. 90.9±10, p=0.001), hemoglobin A1c(5.37±0.52 vs 5.25±0.53, p=0.006), and as well as for waist circumference(92.2±14 vs. 91.4±13.9, p=0.03) was found after treatment. Data for body weight, systolic and diastolic blood pressure and triglyceride level remained without any significant changes.

CONCLUSION

H. pylori eradication could relatively reduce the risk of metabolic syndrome criteria such as fasting blood sugar, hemoglobin A1c, lipid profile and waist circumference.

Helicobacter pylori is associated with dyslipidemia but not with other risk factors of cardiovascular disease

Epidemiologic and clinical data suggest that Helicobacter pylori infection is a contributing factor in the progression of atherosclerosis. However, the specific cardiovascular disease risk factors associated with H. pylori remain unclear. We performed a cross-sectional study of 37,263 consecutive healthy subjects who underwent a routine health check-up. In multivariable log Poisson regression models adjusted for potential confounders, the associations of H. pylori seropositivity with higher LDL-C (relative risk [RR], 1.21; 95% confidence interval [CI], 1.12–1.30) and lower HDL-C level (RR, 1.10; 95% CI, 1.01–1.18) were significant and independent. In multiple linear regression analyses, H. pylori infection was significantly associated with higher total cholesterol level (coefficient = 2.114, P < 0.001), higher LDL-C level (coefficient = 3.339, P < 0.001), lower HDL-C level (coefficient = −1.237, P < 0.001), and higher diastolic blood pressure (coefficient = 0.539, P = 0.001). In contrast, H. pylori infection was not associated with obesity-related parameters (body mass index, waist circumference), glucose tolerance (fasting glucose, glycated hemoglobin), and systolic blood pressure. We found that H. pylori infection was significantly and independently associated with dyslipidemia, but not with other cardiometabolic risk factors, after adjusting for potential risk factors of atherosclerosis.

Association between Bacterial Infection and Peripheral Vascular Disease: A Review

There are an increasing number of data showing a clinically important association between bacterial infection and peripheral artery disease (PAD). Bacteria suspected of being involved in PAD pathogenesis are: periodontal bacteria, gut microbiota, Helicobacter pylori, and Chlamydia pneumoniae. Infectious agents may be involved in the pathogenesis of atherosclerosis via activation of a systemic or local host immunological response to contamination of extravascular tissues or the vascular wall, respectively. A systemic immunological reaction may damage vascular walls in the course of autoimmunological cross-reactions between anti-pathogen antibodies and host vascular antigens (immunological mimicry), pathogen burden mechanisms (nonspecific activation of inflammatory processes in the vascular wall), and neuroendocrine-immune cross-talk. Besides activating the inflammatory pathway, bacterial infection may trigger PAD progression or exacerbation by enhancement of platelet reactivity, by a stimulatory effect on von Willebrand factor binding, factor VIII, fibrinogen, P-selectin activation, disturbances in plasma lipids, increase in oxidative stress, and resistance to insulin. Local inflammatory host reaction and induction of atherosclerotic plaque progression and/or instability result mainly from atherosclerotic plaque colonization by microorganisms. Despite these premises, the role of bacterial infection in PAD pathogenesis should still be recognized as controversial, and randomized, controlled trials are required to evaluate the outcome of periodontal or gut bacteria modification (through diet, prebiotics, and probiotics) or eradication (using antibiotics) in hard and surrogate cardiovascular endpoints.

The relationship between cytotoxin-associated gene A positive Helicobacter pylori infection and autoimmune thyroid disease

OBJECTIVE

The aim of this study was to determine whether there is an association between cagA [cytotoxin-associated gene A] positivity and thyroid autoimmunity and thyroid volume.

METHODS

This prospective study included 78 Helicobacter pylori-positive (H. pylori) dyspeptic patients in the study group, and 50 age-, gender-, and body mass index-matched H. pylori-negative dyspeptic patients in the control group. All the controls were evaluated via upper gastrointestinal endoscopic biopsy or breath test, and were found as H. pylori negative. Gastric biopsy specimens were obtained via endoscopy and histological examination was performed for documentation of H. pylori.

RESULTS

In all, 55.1% (n = 43) of the H. pylori-positive patients were cagA positive. There was no significant difference in metabolic syndrome parameters or thyroid function test results between the study and control groups. The frequency of anti-TPO and Hashimoto's thyroiditis positivity was significantly higher in the study group than in the control group. Thyroid volume was higher and severe parenchymal heterogeneity was more common in the H. pylori-positive patients.

CONCLUSIONS

H. pylori infection might be a risk factor for autoimmune thyroid disease and high thyroid volume in patients diagnosed with histological evaluation. However, cagA positivity has no additional effect on these parameters.

Metabolic consequences of Helicobacter pylori infection and eradication

Helicobacter pylori (H. pylori) is still the most prevalent infection of the world. Colonization of the stomach by this agent will invariably induce chronic gastritis which is a low-grade inflammatory state leading to local complications (peptic ulcer, gastric cancer, lymphoma) and remote manifestations. While H. pylori does not enter circulation, these extragastric manifestations are probably mediated by the cytokines and acute phase proteins produced by the inflammed mucosa. The epidemiologic link between the H. pylori infection and metabolic changes is inconstant and controversial. Growth delay was described mainly in low-income regions with high prevalence of the infection, where probably other nutritional and social factors contribute to it. The timely eradication of the infection will lead to a more healthy development of the young population, along with preventing peptic ulcers and gastric cancer An increase of total, low density lipoprotein and high density liporotein cholesterol levels in some infected people creates an atherogenic lipid profile which could promote atherosclerosis with its complications, myocardial infarction, stroke and peripheral vascular disease. Well designed and adequately powered long-term studies are required to see whether eradication of the infection will prevent these conditions. In case of glucose metabolism, the most consistent association was found between H. pylori and insulin resistance: again, proof that eradication prevents this common metabolic disturbance is expected. The results of eradication with standard regimens in diabetics are significantly worse than in non-diabetic patients, thus, more active regimens must be found to obtain better results. Successful eradication itself led to an increase of body mass index and cholesterol levels in some populations, while in others no such changes were encountered. Uncertainities of the metabolic consequences of H. pylori infection must be clarified in the future.

Clinical significance of Helicobacter pylori infection in patients with acute coronary syndromes: an overview of current evidence

Although Helicobacter pylori (Hp) primarily colonizes gastric mucosa, it can occasionally inhabit in atherosclerotic plaques. Both forms of Hp infection may be involved in the pathogenesis of atherosclerosis via activation of a systemic or local inflammatory host reaction and induction of plaque progression and/or instability, possibly leading to coronary syndromes. The association between Hp infection and cardiovascular endpoint prevalence remains uncertain; however, it has been reported in many epidemiological investigations and may be reasonably explained by pathophysiological mechanisms. Besides the inflammatory pathway, Hp infection may trigger acute coronary syndromes by enhanced platelet reactivity and increased risk of gastrointestinal bleeding (type 2 myocardial infarction). The former seems to be predominantly related to the stimulatory effect of Hp infection on von Willebrand factor-binding and P-selectin activation, and the latter results from cytotoxic bacteria properties and aggravation of digestive tract injury related to aspirin or dual antiplatelet therapy. Despite these premises, the role of Hp infection in cardiovascular syndromes should still be recognized as controversial and requiring randomized, controlled trials to evaluate the outcome of Hp eradication in both cardiac and gastroenterological endpoints. Such need is also justified by potential bias of previous studies resulting from (1) using different diagnostic methods for identification of Hp infection, since only a small number of studies required confirmation of active Hp infection; and from (2) common lack of adjustment for important confounders such as socioeconomic status, smoking and effectiveness of eradication therapy, as well as the genetic characteristics of both the host and the bacterium.

Helicobacter pylori infection and diabetes: Is it a myth or fact?

Helicobacter pylori (H. pylori) is one of the most common human bacterial pathogens, and infection causes a wide array of gastric disorders, including simple gastritis, peptic ulcers and gastric malignancies. Gastrointestinal inflammation caused by H. pylori can influence the absorption of glucose and lipids, which are also abnormal in diabetes mellitus. Type 2 diabetes mellitus (T2DM), formerly known as non-insulin-dependent diabetes mellitus or adult-onset diabetes, is a metabolic disorder that is characterized by high levels of blood glucose resulting from insulin resistance and relative insulin deficiency. It is an emerging pandemic and is rapidly becoming a serious threat to public health. Emerging data now indicate a strong relationship between H. pylori infection and the incidence of T2DM. The mechanisms underlying the pathogenesis of diabetes are complex, involving insulin resistance, chronic inflammation, insulin secretion deficiency as a result of pancreas β-cell dysfunction, glucotoxicity, and lipotoxicity. H. pylori infection is known to be involved in the pathogenesis of insulin resistance, and the growing awareness of its role in diabetes is important for the early detection of glucose dysregulation and prevention of T2DM in high-risk communities. This review probes the possible relationship between H. pylori and diabetes according to epidemiological surveys and discusses putative mechanisms underlying this correlation.

Review article: the effectiveness of standard triple therapy for Helicobacter pylori has not changed over the last decade, but it is not good enough

BACKGROUND  A decrease in the Helicobacter pylori eradication rate after standard triple therapy has been suggested in recent years. AIM  To assess the efficacy of standard triple therapy in the eradication of H. pylori through an epidemiological analysis of all published Spanish trials. A secondary aim was to review the prevalence of clarithromycin resistance in Spain. METHODS  Articles on H. pylori eradication in Spain published in peer-reviewed journals were identified through MEDLINE searches. Studies that included a triple therapy consisting of any proton pump inhibitor with clarithromycin (500 mg b.d.) and amoxicillin (1 g b.d.) for up to 14 days were selected. Spanish studies evaluating the prevalence of clarithromycin resistance were also reviewed. Meta-analysis was performed using the generic inverse variance method. RESULTS The pooled eradication rates by year from Spanish studies evaluating the efficacy of the standard triple regimen revealed a relatively constant rate over the years. Overall, the analysis of the 32 studies (4727 patients) showed a mean H. pylori cure rate of 80% (95% CI = 77-82%) by intention-to-treat and 83% (81-86%) by per-protocol. When only peptic ulcer disease or 7-day regimens were considered, results were similar. Based on 13 studies (3293 patients), mean clarithromycin resistance rate was 8% (5-10%). CONCLUSION Although a decrease in the H. pylori eradication rate after triple therapy has been suggested in recent years, cure rates with this regimen did not change in Spain between 1997 and 2008. However, this by no means indicates that the efficacy of standard triple therapy in Spain is acceptable, as it has been calculated to be around only 80%. Therefore, it is evident that new strategies to improve first-line treatment are urgently needed.

Helicobacter pylori infection and endocrine disorders: Is there a link?

Helicobacter pylori (H pylori) infection is a leading world-wide infectious disease as it affects more than half of the world population and causes chronic gastritis, peptic ulcer disease and gastric malignancies. The infection elicits a chronic cellular inflammatory response in the gastric mucosa. However, the effects of this local inflammation may not be confined solely to the digestive tract but may spread to involve extra-intestinal tissues and/or organs. Indeed, H pylori infection has been epidemiologically linked to extra-digestive conditions and diseases. In this context, it has been speculated that H pylori infection may be responsible for various endocrine disorders, such as autoimmune thyroid diseases, diabetes mellitus, dyslipidemia, obesity, osteoporosis and primary hyperparathyroidism. This is a review of the relationship between H pylori infection and these endocrine disorders.

Serological proteomics of gastritis: degradation of apolipoprotein A-I and alpha1-antitrypsin is a common response to inflammation irrespective of Helicobacter pylori infection

Proteomic technology was employed to analyze serum samples from healthy subjects (10 cases) and gastritis patients with negative and positive Helicobacter pylori (Hp) infection (15 cases each). The serum proteins were separated by two-dimensional (2-D) gel electrophoresis and analyzed by a computer-aided program. The altered proteins in expression were then identified by mass spectrometry and validated by Western blotting. Compared to those in normal control, proteins in at least six areas of 2-D gels were found to significantly increase their expression levels in both Hp-negative and Hp-positive serum samples. These proteins were identified by mass peptide fingerprinting and confirmed by Western blotting to be the truncated or cleaved protein fragments of apolipoprotein A-I and alpha-1 antitrypsin, two well-known acute-phase proteins. We conclude that the degradation or metabolization of acute-phase proteins, apolipoprotein A-I, and alpha1-antitrypsin, is a common response to gastric inflammation irrespective of Hp infection.

Patients with duodenal ulcer have lower levels of serum cholesterol compared to other dyspeptic patients independently of Helicobacter pylori status

OBJECTIVE

The association between Helicobacter pylori (H. pylori) infection and serum lipid profile is still controversial. The aim of this study was to determine any possible relationship between H. pylori infection and the lipid profile of patients with upper gastrointestinal symptoms.

MATERIAL AND METHODS

Consecutively selected 20-70 year-old dyspeptic patients who had undergone esophagogastroduodenoscopy were evaluated for H. pylori infection using both the CLO test and Giemsa staining. Serum total cholesterol (C), HDL-C, LDL-C, apo-A1, apo-B and triglyceride levels were measured.

RESULTS

A total of 137 patients (median age 52.0 years) were studied. Total cholesterol levels were lower in H. pylori-infected patients than in H. pylori-negative patients (mean +/- SEM: 199.3 +/- 5.9 versus 212.6 +/- 4.6 mg/dl, p = 0.08). Patients with duodenal ulcer (DU) had significantly lower levels of all measured lipidemic parameters including cholesterol, with the exception of triglycerides, in comparison with either H. pylori-positive or -negative dyspeptic patients (cholesterol: 177.6 +/- 6.5 versus 214.6 +/- 4.2 mg/dl, p < 0.0001). However, there was no difference in the total cholesterol/HDL-C ratio between DU patients and the rest of the dyspeptic patients.

CONCLUSIONS

Among H. pylori-positive and H. pylori-negative patients there was no difference in lipid profile apart from a trend towards total cholesterol levels being lower in H. pylori-positive patients. However, cholesterol, HDL-C, LDL-C, apo-A and apo-B were all decreased in DU patients even though this reduction did not result in a fall in the total cholesterol/HDL-C ratio. The etiologic factor differentiating the lipid profiles among dyspeptics only in H. pylori-positive patients carrying a DU could be dietetic, microbial, genetic or a combination of all three.

A review of the postulated mechanisms concerning the association of Helicobacter pylori with ischemic heart disease

Since its discovery, Helicobacter pylori has been implicated in the pathogenesis of several diseases, both digestive and extradigestive. Interestingly, the majority of the extradigestive-related literature is focused on two vascular manifestations: stroke and ischemic heart disease. Potential mechanisms for the establishment of a H. pylori-induced ischemic heart disease have been proposed with regard to chronic inflammation, molecular mimicry, oxidative modifications, endothelial dysfunction, direct effect of the microorganism on atherosclerotic plaques as well as changes regarding traditional or novel risk factors for ischemic heart disease or even platelet-H. pylori interactions. A positive link between H. pylori infection and ischemic heart disease has been suggested by a series of studies focusing on epidemiologic evidence, dyslipidemic alterations, upregulation of inflammatory markers or homocysteine levels, induction of hypercoagulability, oxidation of low-density lipoprotein, causation of impaired endothelial function, detection of H. pylori DNA in atherosclerotic plaques, and participation of certain antigens and antibodies in a cross-reactivity model. There are studies, however, which investigated the relationship between H. pylori and ischemic heart disease with regard to the same parameters and failed to confirm the suggested positive association. Further studies in the direction of interaction between H. pylori and the host's genotype as well as a quest for evidence towards novel risk factors for ischemic heart disease such as oxidative stress, vascular remodeling, vascular calcification, or vasomotor activity, may reveal a field of great interest, thus contributing to the determination of new potential mechanisms.

A randomized factorial study of the effects of long-term garlic and micronutrient supplementation and of 2-wk antibiotic treatment for Helicobacter pylori infection on serum cholesterol and lipoproteins

BACKGROUND

Little is known about the long-term effects of garlic or micronutrient supplementation on total, HDL, and LDL cholesterol in disease-free persons.

OBJECTIVE

We aimed to assess the effects of long-term supplementation with garlic and micronutrients and of short-term amoxicillin and omeprazole treatment on serum total, HDL, and LDL cholesterol in a rural Chinese population.

DESIGN

We conducted a randomized, double-blind, placebo-controlled, 2 x 2 x 2 and 2 x 2 factorial study of precancerous gastric lesions in 3411 subjects in Linqu County, Shandong Province, China. Thirty-four subjects were randomly selected from each of 12 treatment strata. Sera were analyzed at 3.3 and 7.3 y to measure effects on total, HDL, and LDL cholesterol after 2-wk twice-daily treatment with 1 g amoxicillin and 20 mg omeprazole and supplementation throughout the study with 1) 2 capsules twice daily, each containing 200 mg aged garlic extract and 1 mg steam-distilled garlic oil, or 2) twice-daily micronutrient capsules containing 250 mg vitamin C, 100 IU vitamin E, and 37.5 mg selenium.

RESULTS

Regressions adjusted for covariates indicated increases of 0.22 mmol total cholesterol/L (P = 0.01) and 0.19 mmol LDL/L (P = 0.02) after 7.3 y of micronutrient supplementation, but no effect of garlic supplementation or short-term amoxicillin and omeprazole treatment.

CONCLUSIONS

In this rural Chinese population with low meat intake and moderate cholesterol concentrations, long-term garlic supplementation had no effect on lipid profiles, whereas micronutrient supplementation was associated with small but significant increases in total and LDL-cholesterol concentrations at 7.3 y.

Effects of Helicobacter pylori eradication on platelet activation and disease recurrence in patients with acute coronary syndromes

BACKGROUND

Platelet activation is consistently observed in animal models of Helicobacter pylori infection and could help to explain the alleged epidemiological association between H. pylori and coronary heart disease.

MATERIALS AND METHODS

Ninety-two patients with recent acute coronary syndromes were enrolled. Helicobacter pylori-positive patients were randomized to receive a 7-day course of omeprazole, amoxycillin and metronidazole or placebos. Two months later, H. pylori status was reassessed and baseline parameters, including soluble P-selectin and platelet surface expression of CD62P, CD63 and CD41, were measured again. Patients were followed-up for 1 year or until death or readmission.

RESULTS

No baseline differences were observed between H. pylori-positive and -negative cases. Among H. pylori-positive patients, 18 received placebo and 31 received active medication resulting in eradication in 21 cases. No differences were observed in inflammatory parameters or platelet activation markers between patients with persistent or resolved H. pylori infection. However, coronary events recurred at 6 and 12 months, respectively, in 35% and 55% of patients with persisting H. pylori infection compared with 10% and 25% of patients in whom H. pylori was either absent or eradicated (p = .01). Only final H. pylori status [RR 3.07 (95% CI 1.35-98)] and number of coronary risk factors [RR 2.58 (95% CI 1.51-4.41)] were independent predictors of recurrence.

CONCLUSIONS

Infection with H. pylori does not induce significant platelet activation in patients treated for coronary disease. Helicobacter pylori-infected patients, however, may have an increased risk of recurrence of coronary events.

Helicobacter pylori eradication decreases blood neutrophil and monocyte counts

BACKGROUND

The effect of Helicobacter pylori infection on systemic disorders is not well understood.

AIM

The purpose of this study was to elucidate the systemic effects of H. pylori infection by comparing differential counts of leukocytes and platelets in peripheral blood before and after eradication of H. pylori.

METHODS

A total of 164 H. pylori-positive patients underwent eradication therapy, and populations of peripheral blood leukocytes and platelets before and 0 (just after therapy), 1, 3 and 12 months after eradication were retrospectively analysed.

RESULTS

In the eradicated group (n = 138), blood leukocytes, neutrophils and monocytes decreased significantly after eradication, but there was no significant change in eosinophils, basophils, lymphocytes or platelets. In the non-eradicated group (n = 26), there was no significant change in any studied parameter. With regard to smoking status, although leukocytes and neutrophils did not decrease after eradication in the smoking group, they significantly decreased after eradication in the nonsmoking group.

CONCLUSIONS

These findings suggest that: (1) H. pylori infection increases neutrophil and monocyte counts in the peripheral blood, which indicates a significant role of H. pylori infection in systemic disorders; and (2) Smoking may mask the effect of H. pylori eradication on peripheral leukocytes, which would explain the controversy in previous reports concerning H. pylori infection and peripheral leukocytes.

Five month persistence of Helicobacter pylori infection in guinea pigs

Seven Dunkin-Hartley guinea pigs were infected with the Sydney strain of H. pylori (SS1). Gastric histopathology was evaluated and serum antibody response to H. pylori cell-surface proteins was analysed by enzyme immunoassay (EIA) and immunoblot. Tissue and faecal samples from five control animals were analysed for the presence of naturally occurring Helicobacter spp. infection by culture and Helicobacter genus-specific PCR. The H. pylori infection persisted for 5 months, in most animals accompanied by a histologically severe antral gastritis, exhibiting focal degeneration and necrosis of gastric crypt epithelium. Increased numbers of mitotic figures were observed in the gastric epithelium, indicating a regenerative process. Infected animals displayed specific antibodies towards H. pylori cell-surface proteins in immunoblot, whereas EIA was of dubious value creating false-positive results. Serum complement C3 and cholesterol levels appeared to be elevated in infected animals. Helicobacter spp. infection was not detected in the control animals. The persistent infection, accompanied by severe gastritis and a prominent serum antibody response, and the apparent absence of a natural Helicobacter spp. infection makes the guinea pig model useful in H. pylori research.