Gastric Helicobacter pylori infection associated with risk of diabetes mellitus, but not prediabetes

Association between Helicobacter pylori antibodies and otolaryngological diseases

OBJECTIVE

Observational studies have shown that Helicobacter pylori is related to some otolaryngological diseases. However, it is unclear if H. pylori infection causally affects these diseases. To elucidate H. pylori role in 12 common otolaryngological diseases, we conducted two-sample Mendelian randomization analysis.

METHODS

Single-nucleotide polymorphisms associated with 7 H. pylori antibodies (IgG, CagA, Catalase, GroEL, OMP, UREA and Vac A) served as instrumental variables. We primarily employed random-effects inverse variance weighting for causal estimation, supplemented by MR Egger, weighted median, simple mode, and weighted mode. Sensitivity analyses, including heterogeneity, pleiotropy, and leave-one-out tests, validated robustness.

RESULTS

MR analysis using inverse variance weighting (random effects) revealed genetically predicted H. pylori CagA antibodies correlated with increased risk of nonsuppurative otitis media (OR = 1.0778, 95% CI 1.0114-1.1487, p-value = 0.021). No causal relationship was observed between H. pylori antibodies and other common otolaryngological diseases. Sensitivity analyses found no pleiotropy or heterogeneity, affirming result reliability.

CONCLUSION

This study suggests that the levels of H. pylori CagA antibodies may contribute to the development of nonsuppurative otitis media. Further studies are needed in the future to elucidate the specific mechanism of H. pylori in this disease.

LEVEL OF EVIDENCE

Level III.

Is Diabetes Mellitus a Predisposing Factor for Helicobacter pylori Infections?

PURPOSE OF REVIEW

This review aims to analyse the consistency of reports suggesting the role of Diabetes Mellitus in the pathogenesis of Helicobacter pylori (H. pylori).

RECENT FINDINGS

There have been numerous controversies citing the prevalence of H. pylori infections in patients suffering from type 2 diabetes mellitus (T2DM). This review investigates the possible crosstalk between H. pylori infections and T2DM and also designs a meta-analysis to quantify the association. Subgroup analyses have also been conducted to deduce factors like geography and testing techniques, in playing a role in stratification analysis. Based on a scientific literature survey and meta-analysis of databases from 1996 to 2022, a trend towards more frequent H. pylori infections in patients with diabetes mellitus was observed. The highly diversified nature of H. pylori infections across age, gender, and geographical regions requires large interventional studies to evaluate its long-term association with diabetes mellitus. Further possible linkage of the prevalence of diabetes mellitus concomitant with that of H. pylori infected patients has also been delineated in the review.

Peptic Ulcer Disease Associated with Central Obesity

This retrospective cross-sectional study aimed to evaluate associations between peptic ulcer disease (PUD), bone mineral density, and metabolic syndrome (MetS) and its components in healthy populations. Data were collected from the health examination database of a tertiary medical center in southern Taiwan from January 2015 to December 2016. Subjects who had undergone metabolic factors assessment, upper gastrointestinal endoscopy, and dual energy X-ray absorptiometry scans were enrolled. In total, 5102 subjects were included, with mean age 52.4 ± 12.0 years. Among them, 1332 (26.1%) had PUD. Multivariate logistic regression analysis showed that age (OR 1.03, p < 0.001), male (OR 1.89, p < 0.001), diabetes (OR 1.23, p = 0.004), BMI (OR 1.03, p = 0.001), and GOT (OR 1, p = 0.003) are risk factors for PUD. Regarding MetS parameters, larger waist circumference (OR 1.26, p = 0.001) is associated with PUD, and high triglycerides (OR 1.20, 95% CI 1.01−1.43) is associated with gastric ulcer, while low HDL (OR 1.31, 95% CI 1.07−1.59) and osteoporosis (OR 1.44, 95% CI 1.08−1.91) are associated with duodenal ulcer. In conclusion, central obesity is associated with PUD in a middle-aged healthy population. Subjects with high triglycerides are prone to gastric ulcers, and those with osteoporosis and low HDL are prone to duodenal ulcers.

Declining trends of prevalence of Helicobacter pylori infection and incidence of gastric cancer in Taiwan: An updated cross-sectional survey and meta-analysis

BACKGROUND

We aimed to assess the latest prevalence and secular trend of Helicobacter pylori infection and its association with the incidence and mortality of gastric cancer in Taiwan.

MATERIALS AND METHODS

Adults naive to H. pylori eradication received ¹³ C-urea breath test (¹³ C-UBT), H. pylori stool antigen test, and serology test during 2019-2020 in this prospective screening program. Children and adolescent aged between 7 and 19 years received ¹³ C-UBT for H. pylori screening. We also conducted a systematic review and meta-analysis to assess the secular trend of prevalence of H. pylori from 1990 to 2020 in Taiwan. The secular trends of age-standardized incidence and mortality of gastric cancer were obtained from the Taiwan Cancer Registry.

RESULTS

A total of 1494 participants were enrolled, including 294 children or adolescents and 1200 adults. The overall prevalence of active H. pylori infection by ¹³ C-UBT was 26.6% (397/1494), which was 30.8% in adults and 9.5% in adolescents/children. The age-standardized prevalence of active H. pylori infection was 32.3% in adults after adjustment of the population structure in Taiwan. Of the 29 studies including 38,597 subjects eligible for the meta-analysis, the pooled prevalence of H. pylori infection decreased from 63.8% (95% CI: 55.9%-71%) in 1990-2000 to 28.2% (95% CI:21.8%-35.6%) in 2016-2020. The age-standardized incidence and mortality of gastric cancer have also declined from 15.2 to 10.75 per 100,000, respectively, in 1999 to 9.29 and 5.4 per 100,000, respectively, in 2019.

CONCLUSIONS

The prevalence of H. pylori infection has declined in Taiwan, which correlates with the declining trends of age-standardized incidence and mortality of gastric cancer in Taiwan.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

Helicobacter pylori in Human Stomach: The Inconsistencies in Clinical Outcomes and the Probable Causes

Pathogenic potentials of the gastric pathogen, Helicobacter pylori, have been proposed, evaluated, and confirmed by many laboratories for nearly 4 decades since its serendipitous discovery in 1983 by Barry James Marshall and John Robin Warren. Helicobacter pylori is the first bacterium to be categorized as a definite carcinogen by the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO). Half of the world’s population carries H. pylori, which may be responsible for severe gastric diseases like peptic ulcer and gastric cancer. These two gastric diseases take more than a million lives every year. However, the role of H. pylori as sole pathogen in gastric diseases is heavily debated and remained controversial. It is still not convincingly understood, why most (80–90%) H. pylori infected individuals remain asymptomatic, while some (10–20%) develop such severe gastric diseases. Moreover, several reports indicated that colonization of H. pylori has positive and negative associations with several other gastrointestinal (GI) and non-GI diseases. In this review, we have discussed the state of the art knowledge on “H. pylori factors” and several “other factors,” which have been claimed to have links with severe gastric and duodenal diseases. We conclude that H. pylori infection alone does not satisfy the “necessary and sufficient” condition for developing aggressive clinical outcomes. Rather, the cumulative effect of a number of factors like the virulence proteins of H. pylori, local geography and climate, genetic background and immunity of the host, gastric and intestinal microbiota, and dietary habit and history of medicine usage together determine whether the H. pylori infected person will remain asymptomatic or will develop one of the severe gastric diseases.

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.

Increased Glycated Hemoglobin Levels in Patients With Helicobacter pylori Infection Are Associated With the Grading of Chronic Gastritis

Background

Recent studies have found an association between Helicobacter pylori infection and prediabetes. Whether H. pylori per se or host factors are involved in the disturbance of glycated hemoglobin needs further investigation. The aim of this study was to determine the association of glycated hemoglobin levels with endoscopic diagnosis and the inflammatory response in H. pylori infection.

Methods

A cross-sectional study was carried out in 88 dyspeptic non-diabetic adults who underwent esophagogastroduodenoscopy. The diagnosis of H. pylori infection was performed through urease test and histopathological exam. Cases were initially distributed into two groups: control (without H. pylori infection, n = 22) and HP (patients with H. pylori infection, n = 66). HbA1c was measured to determine prediabetes status according to the American Diabetes Association criteria, and then the groups were subdivided into non-prediabetic (n = 14), prediabetic (n = 8), non-prediabetic HP (n = 26) and prediabetic HP (n = 40) groups. Gastric mucosa was histologically evaluated to determine H. pylori density and inflammatory activity according to Sydney System. To investigate the balance of anti-inflammatory and pro-inflammatory cytokines we measured interleukin 10 (anti-inflammatory) and Tumor Necrosis Factor-a (pro-inflammatory) in the plasma or in the gastric mucosa.

Results

Patients with H. pylori infection had higher mean HbA1c levels than those without H. pylori infection. However, increased HbA1c levels were not associated with H. pylori-related factors but with the bacterial density, the intensity of inflammation and the activity of the chronic gastritis. In addition, H. pylori infection per se did not alter IL-10 and TNF-α neither in the plasma nor in the gastric mucosa, but the bacterial density was negatively correlated with systemic and local IL-10 expression. Although no correlation was found between systemic cytokines and HbA1c levels, local anti-inflammatory cytokine was correlated with HbA1c levels.

Conclusion

Long-term H. pylori infection is associated with prediabetes. This association is not related to the presence of H. pylori per se but depends on the extent of bacterial colonization and the degree of both local inflammation and activity of the chronic gastritis.

Comprehensive analysis of Helicobacter pylori infection-associated diseases based on miRNA-mRNA interaction network

Helicobacter pylori (H. pylori) infection remains a cause of significant morbidity and mortality worldwide. Comprehensive understanding of the pathogenic mechanism of H. pylori and its interaction with host will contribute to developing novel prophylactical and therapeutical strategies. Here, we first determined microRNA (miRNA) levels in H. pylori-infected patients with gastritis, duodenal ulcer, gastric cancer or mucosa-associated lymphoid tissue lymphoma using miRNA data sets. Thirty-four differentially expressed miRNAs were identified and functional enrichment analysis of those miRNA target genes revealed that H. pylori infection were strongly associated with pathway in cancer and regulation of mRNA synthesis. Using disease connectivity analysis of 28 hub genes, we found that H. pylori may increase the risk of many extragastric diseases (e.g. cardiovascular disease, hemic and lymphatic diseases and nervous system disease). Altogether, our integrated analysis provided a new method to predict pathogen–human disease connectivity based on miRNA-mRNA interaction network and indicated anti-H. pylori therapy as an effective means of human diseases prevention.

Helicobacter pylori infection is associated with diabetes among Chinese adults

AIMS/INTRODUCTION

Several epidemiological studies investigated the effect of Helicobacter pylori infection on diabetes, but the conclusions remained inconsistent. We aimed to explore the relationship between H. pylori infection and diabetes, as well as glycemic metabolism profiles.

MATERIALS AND METHODS

A cross-sectional study including 58,482 Chinese adults was carried out between January 2016 and December 2017. H. pylori infection was diagnosed by the 13 C-urea breath test. Multivariate regression analyses were carried out to evaluate the association of H. pylori infection with diabetes.

RESULTS

Of the 58,482 participants, 3,449 (5.9%) had diabetes. The H. pylori-positive participants had a higher rate of diabetes (7.3% vs 5.2%, P < 0.001), and higher levels of fasting plasma glucose (5.36 ± 1.12 mmol/L vs 5.28 ± 0.95 mmol/L, P < 0.001) and glycated hemoglobin A1c (5.63 ± 0.68% vs 5.57 ± 0.60%, P < 0.001) than the H. pylori negative group. Multivariate regression analyses showed that H. pylori infection was positively related to diabetes (odds ratio 1.25, 95% confidence interval 1.15-1.35). Among the H. pylori-positive participants, the elevated levels of fasting plasma glucose and glycated hemoglobin A1c were 0.033 mmol/L (95% confidence interval 0.016-0.049 mmol/L) and 0.024% (95% confidence interval 0.008-0.041%), respectively. Additionally, H. pylori infection was significantly related to diabetes in participants aged ≥44 years, but not in participants aged <44 years.

CONCLUSIONS

The present study showed that H. pylori infection is associated with diabetes among Chinese adults. More attention should be paid to adults with H. pylori infection for effective prevention of diabetes.

Factors influencing breath analysis results in patients with diabetes mellitus

Breath analysis is used to detect the composition of exhaled gas. As a quick and non-invasive detection method, breath analysis provides deep insights into the progression of various kinds of diseases, especially those with metabolism disorders. Abundant information on volatile compounds in diabetic patients has been studied in numerous articles in the literature. However, exhaled gas in diabetic patients can be altered by various complications. So far, little attention has been paid to this alteration. In our paper, we found that under air pollution conditions, diabetic patients exhale more nitric oxide. Diabetic patients with heart failure exhale more acetone than those without heart failure. After ¹³C-labeled glucose intake, patients infected with Helicobacter pylori exhaled more ¹³C and less ¹⁸O than those without infection. Exhalation with chronic kidney disease changes volatile organic compounds on a large scale. Diabetic patients with ketoacidosis exhale more acetone than those without ketoacidosis. Some specific volatile organic compounds also emanate from diabetic feet. By monitoring breath frequency, diabetic patients with obstructive sleep apnea syndrome exhibit a unique breath pattern and rhythm as compared with other diabetic patients, and sleep apnea is prevalent among diabetic patients. In addition to clinical findings, we analyzed the underlying mechanisms at the levels of molecules, cells and whole bodies, and provided suggestions for further studies.

Prediabetes and gastrointestinal (GI) symptoms; a cross-sectional study

AIMS

Prediabetes associate with known micro and macrovascular complications of diabetes. Also gastrointestinal symptoms are present in diabetics higher than general population. The aim of this study was evaluation of gastrointestinal symptoms in subjects with prediabetes.

METHODS

This analytical cross-sectional study was conducted on 130 persons 30-65 years old, 65 pre-diabetic patients and 65 persons without glucose disorders from 2014 to 2015 in YAZD province. FBS and HbA1c used for diagnosis prediabetes. Demographic and medical history were collected. A questionnaire according to Rome III Criteria was used to collect digestive information (diarrhea, abdominal pain, constipation, abdominal bloating, heartburn, increased gas passing, nausea, intermittent diarrhea and constipation in the last 6 months ago). Frequency of GI symptoms in subjects with and without glucose disorders were compared. Data were analyzed by SPSS software Version 20. Data were reported as mean ± standard deviation or frequency and T-test, Chi Square and Spearman correlation coefficient tests were used. P-value less than 0.05 were considered statistically significant.

RESULTS

Higher frequency of bloating, early satiety, nausea, heartburn, gas passing and constipation are seen in the pre-diabetes group than in the control group; (p-value 0.0001, 0.0001, 0.0001, 0.0001, 0.001 and 0.0001 respectively). 96.9% in prediabetics had at least one gastrointestinal symptom, while in the normal groups 50% had at least one GI symptom (p-value: 0.0001).

CONCLUSIONS

Gastrointestinal symptoms were seen in prediabetics higher than healthy persons. So, prediabetes can not be considered an entirely benign and asymptomatic condition. Lifestyle interventions maybe necessary at this state.

H. pylori infection and extra-gastroduodenal diseases

Helicobacter pylori infection is the principal cause of peptic ulcer disease, gastric adenocarcinoma and gastric mucosa-associated lymphoid tissue lymphoma. Recent studies have shown that it may interfere with many biological processes and determine or influence the occurrence of many diseases outside the stomach. Currently, the role of H. pylori in idiopathic thrombocytopenic purpura and iron deficiency anemia is well documented. Emerging evidence suggests that it may also contribute to vitamin B12 deficiency, insulin resistance, metabolic syndrome, diabetes mellitus and non-alcoholic liver disease. Additionally, it may increase the risk of acute coronary syndrome, cerebrovascular disease, neurodegenerative disease and other miscellaneous disorders. Different pathogenic mechanisms have been hypothesized, including the occurrence of molecular mimicry and the induction of a low-grade inflammation. This review summarizes the results of the most relevant studies on the extra-gastroduodenal manifestations of H. pylori infection.

Helicobacter pylori and extragastric diseases: A review

Helicobacter pylori (H. pylori) infection is very common and affects approximately half of the world population. It causes gastric diseases, but some authors have reported an association of H. pylori infection with other systemic manifestations beginning in 1994. The list of potential effects of H. pylori outside the stomach includes a number of extragastric manifestations and we focused on neurological, dermatological, hematologic, ocular, cardiovascular, metabolic, allergic, and hepatobiliary diseases. This review discusses these important reported manifestations that are not related to the gastrointestinal tract.

Non-invasive diagnosis of type 2 diabetes in Helicobacter pylori infected patients using isotope-specific infrared absorption measurements

Helicobacter pylori causes several gastrointestinal diseases and may also contribute to the development of type 2 diabetes (T2D). Several studies suggest that there might be a potential link between H. pylori infection and T2D, but it still remains the subject of debate. Here, we first report the cumulative effect of H. pylori infection and T2D by exploiting the excretion kinetics of ¹³C/¹²C and ¹⁸O/¹⁶O isotope ratios of exhaled breath CO₂ in response to an oral dose of ¹³C-enriched glucose in individuals with T2D and non-diabetic controls (NDC) harbouring the H. pylori infection. Using a high-resolution integrated cavity output spectroscopy (ICOS) technique in the infrared region, we observed that the isotopic fractionations of ¹³C and ¹⁸O in breath CO₂ are distinctly altered in H. pylori infected T2D patients as well as in H. pylori infected NDC. Several optimal diagnostic cut-off points of ¹³C and ¹⁸O isotopes of breath CO₂ were also determined which exhibited the diagnostic sensitivity and specificity of ∼97 % and thus suggesting that breath ¹³C and ¹⁸O isotopes might be considered as potential biomarkers for the non-invasive assessment of the gastric pathogen prior to the onset of T2D. This may open a new diagnostic strategy for treating these common diseases in an alternative way.

[New aspects of Helicobacter pylori infection: Association with metabolic disturbances]

The review is devoted to the analysis of the literature on the possible association of Helicobacter pylori infection with type 2 diabetes mellitus, metabolic syndrome and its supposed mechanisms.

Helicobacter pylori Infection Is Associated with Type 2 Diabetes, Not Type 1 Diabetes: An Updated Meta-Analysis

BACKGROUND

Extragastric manifestations of Helicobacter pylori (H. pylori) infection have been reported in many diseases. However, there are still controversies about whether H. pylori infection is associated with diabetes mellitus (DM). This study was aimed at answering the question.

METHODS

A systematic search of the literature from January 1996 to January 2016 was conducted in PubMed, Embase databases, Cochrane Library, Google Scholar, Wanfang Data, China national knowledge database, and SinoMed. Published studies reporting H. pylori infection in both DM and non-DM individuals were recruited.

RESULTS

79 studies with 57,397 individuals were included in this meta-analysis. The prevalence of H. pylori infection in DM group (54.9%) was significantly higher than that (47.5%) in non-DM group (OR = 1.69, P < 0.001). The difference was significant in comparison between type 2 DM group and non-DM group (OR = 2.05), but not in that between type 1 DM group and non-DM group (OR = 1.23, 95% CI: 0.77-1.96, P = 0.38).

CONCLUSION

Our meta-analysis suggested that there is significantly higher prevalence of H. pylori infection in DM patients as compared to non-DM individuals. And the difference is associated with type 2 DM but not type 1 DM.

Helicobacter pylori and gut microbiota in multiple sclerosis versus Alzheimer's disease: 10 pitfalls of microbiome studies

Alteration of microbiota has been associated with intestinal, inflammatory, and neurological diseases. Abundance of "good bacteria" such as Bifidobacterium, or their products have been generally believed to be beneficial for any diseases, while "bad bacteria" such as pathogenic Helicobacter pylori are assumed to be always detrimental for hosts. However, this is not the case when we compare and contrast the association of the gut microbiota with two neurological diseases, multiple sclerosis (MS) and Alzheimer's disease (AD). Following H. pylori infection, pro-inflammatory T helper (Th)1 and Th17 immune response are initially induced to eradicate bacteria. However, H. pylori evades the host immune response by inducing Th2 cells and regulatory T cells (Tregs) that produce anti-inflammatory interleukin (IL)-10. Suppression of anti-bacterial Th1/Th17 cells by Tregs may enhance gastric H. pylori propagation, followed by a cascade reaction involving vitamin B12 and folic acid malabsorption, plasma homocysteine elevation, and reactive oxygen species induction. This can damage the blood-brain barrier (BBB), leading to accumulation of amyloid-β in the brain, a hallmark of AD. On the other hand, this suppression of pro-inflammatory Th1/Th17 responses to H. pylori has protective effects on the hosts, since it prevents uncontrolled gastritis as well as suppresses the induction of encephalitogenic Th1/Th17 cells, which can mediate neuroinflammation in MS. The above scenario may explain why chronic H. pylori infection is positively associated with AD, while it is negatively associated with MS. Lastly, we list "10 pitfalls of microbiota studies", which will be useful for evaluating and designing clinical and experimental microbiota studies.

The Correlation and Risk Factors between Carotid Intima-Media Thickening and Alcoholic Liver Disease Coupled with Helicobacter pylori Infection

The aim of this study was to explore the associations and differences in influencing factors between alcoholic liver disease (ALD) coupled with Helicobacter pylori infection and atherosclerosis and to determine whether there is a "double hit phenomenon" in atherosclerosis patients with ALD and H. pylori infections. Included cases (n = 160) were categorized into 4 groups: 41 cases of ALD coupled with H. pylori infections (group A), 35 cases of H. pylori infections without ALD (group B), 37 cases of ALD without H. pylori infections (group C), and 47 normal control cases (group D). CIMT was significantly greater in group A than in groups B and D (P = 0.005 and P = 0.001, respectively). The GLM univariate analysis found that CIMT was significantly greater in group A than in groups B, C and D (P = 0.018, P = 0.001 and P = 0.009, respectively). We found that BMI and ALT, AST and ApoB levels were independent predictors of CIMT (P = 0.000, P = 0.000, P = 0.012 and P = 0.014, respectively). ALD coupled with H. pylori infection may result in significant CIMT thickening, but H. pylori infection without ALD and ALD without H. pylori infection does not, suggesting that a "double hit phenomenon" occurs. Additionally, BMI, and ALT, AST and ApoB levels were independent risk factors for increased CIMT.

The Impact of Gastric Atrophy on the Incidence of Diabetes

Gastric atrophy results in lower plasma ghrelin, higher gastrin secretion, a change in gut microbiota, and altered dietary nutrient absorption, which may be associated with the incidence of diabetes. Helicobacter pylori (H. pylori) infection is a major cause of gastric atrophy and is associated with diabetes in some reports. Since there is no study which investigates the impact of gastric atrophy on diabetes, we conduct a prospective cohort study to examine the relationship between H. pylori infection, gastric atrophy, and incident diabetes. In this study, subjects with gastric atrophy had a lower risk of incident diabetes, compared to those without gastric atrophy. The extent of gastric atrophy, measured by serum pepsinogen (PG) I/II ratio, was correlated with age, H. pylori IgG titer, HOMA2-IR, and HOMA2%B. When gastric atrophy is more extensive, presented as a lower serum PG I/II ratio, the risk of incident diabetes is lower. On the other hand, there was no significant association between H. pylori infection and the incidence of diabetes. In conclusion, the presence and the extent of gastric atrophy, but not H. pylori infection, are associated with incident diabetes. Further studies are needed to investigate the detailed mechanisms and the potential applications of the findings to guide diabetes screening and treatment strategies.

Association of Helicobacter pylori infection with type 2 diabetes

The last three decades have witnessed a rapid rise in the number of people with type 2 diabetes (T2DM), and China has the largest population of diabetes in the world. Patients with T2MD are more susceptible to a variety of infections due to impaired host immunity. Helicobacter pylori (H. pylori) hosted in the human stomach is the pathogen of a series of gastric and extragastric diseases, and has infected > 50% of the world population. H. pylori infection is rapidly becoming a serious threat to public health. Epidemiological surveys have indicated an obvious relationship between H. pylori and diabetes. H. pylori infection in T2MD cases can induce systemic inflammation, increase the risk of diabetic nephropathy and retinopathy, and is associated closely with the micro- and macro-vascular complications. Chronic H. pylori infection may have a harmful impact on pancreatic β-cells and may be a risk factor for T2MD and insulin resistance. Treatment of H. pylori infection and control of T2MD are becoming increasingly challenging due largely to the huge population of patients with the two diseases and to the relative complexity of treatment regimens. Further clinical and basic studies are needed to control H. pylori infection and T2MD effectively.

Helicobacter pylori infection and diabetes mellitus

The rate of Helicobacter pylori (H. pylori) infection increases significantly in patients with diabetes mellitus. H. pylori infection as an independent factor can promote insulin resistance. H. pylori eradication rate is much lower in diabetic patients than in normal controls. Blood glucose levels tend to fluctuate more widely, and is not easy to be controlled in diabetic patients with H. pylori infection. Eradication of H. pylori can help to improve diabetic progression. H. pylori infection is related to the occurrence of diabetic complications, such as diabetic nephropathy, atherosclerosis, and gastroparesis. The mechanism of H. pylori infection affecting diabetes mellitus may be related to systemic inflammatory response, vascular endothelial damage and changes of hormone levels such as leptin and ghrelin.

Current views of the relationship between Helicobacter pylori and Henoch-Schonlein purpura in children

Helicobacter pylori (H. pylori) is one of the factors involved in the pathogenesis of various gastrointestinal diseases and may play a potential role in certain extra-intestinal diseases. H. pylori infection are mainly acquired during childhood, and it has been reported that in endemic areas of China the infection rates are extraordinarily higher in HSP children, particular those with abdominal manifestations. Furthermore, eradication therapy may ameliorate Henoch-Schonlein purpura (HSP) manifestations and decrease the recurrence of HSP. Therefore, results suggested that detection of H. pylori infection by appropriate method ought to be applied in HSP children. Current evidences indicate that local injury of gastric mucosa and immunological events induced by H. pylori infection are involved in the development of HSP. Increased serum IgA, cryoglobulins, C3 levels, autoimmunity, proinflammatory substances and molecular mimicry inducing immune complex and cross-reactive antibodies caused by H. pylori infection might play their roles in the course of HSP. However, there are no investigations confirming the causality between H. pylori infection and HSP, and the pathogenesis mechanism is still unclear. More bench and clinical studies need to be executed to elaborate the complex association between H. pylori and HSP.

Potential effect of chronic Helicobacter pylori infection on glucose metabolism of Mongolian gerbils

AIM: To assess the effect of Helicobacter pylori (H. pylori) infection on metabolic parameters in Mongolian gerbils.

METHODS: A total of 40 male, 5- to 8-wk-old, specific-pathogen-free Mongolian gerbils (30-50 g) were randomly allocated into two groups: a control group (n = 20) and an H. pylori group (n = 20). After a two-week acclimation period, the control group was administered Brucella broth and the H. pylori group was challenged intra-gastrically five times every other day with approximately 10⁹/CFU H. pylori ATCC43504 (CagA+, VacA+). Each group was then divided into two subgroups, which were sacrificed at either 6 or 12 mo. The control and H. pylori subgroups each contained 10 Mongolian gerbils. Body weight, abdominal circumference, and body length were measured, and body mass index (BMI) and Lee’s index were calculated. Biochemical assays were used to detect serum indexes, including glucose, glycated hemoglobin (GHb), glycated hemoglobin A1c (HbA1c), triacylglycerol, and total cholesterol, using an automatic biochemistry analyzer. Inflammatory cytokines, including interleukin (IL)-1β, IL-2, IL-4, IL-10, IL-12, tumor necrosis factor-α (TNF-α) and interferon (IFN)-γ, were assayed using ELISA. The expression of insulin and insulin-like growth factor 1 (IGF-1) was detected by immunohistochemistry, and islet apoptosis was measured using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay.

RESULTS: At each time point, body weight, abdominal circumference, BMI, and Lee’s index were increased after H. pylori infection. However, these differences were not significant. H. pylori infection significantly increased the GHb (5.45 ± 0.53 vs 4.98 ± 0.22, P < 0.05) and HbA1c (4.91 ± 0.61 vs 4.61 ± 0.15, P < 0.05) levels at 12 mo. We observed no significant differences in serum biochemical indexes, including fasting blood glucose, triacylglycerol and total cholesterol, at 6 or 12 mo after infection. H. pylori infection significantly increased the expression of IGF-1 (P < 0.05). Insulin levels from the pancreas and the apoptotic rate of islet β-cells remained unchanged. Also, we observed no significant differences among cytokines levels, including IL-1β, IL-2, IL-4, IL-10, IL-12, TNF-α and IFN-γ. IL-4 was the only exception, which increased at 6 (44.36 ± 25.17 vs 17.38 ± 3.47, P < 0.05) and 12 mo (33.41 ± 10.00 vs 18.91 ± 5.31, P < 0.05) after H. pylori infection.

CONCLUSION: Long-term H. pylori infection is significantly associated with high levels of HbA1c in Mongolian gerbils, indicating a potential role of H. pylori infection in glucose dysregulation.

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.

Helicobacter pylori infection prevalence: Is it different in diabetics and nondiabetics?

BACKGROUND

Helicobacter pylori (HP) infection plays a significant role in the development of gastrointestinal complications and has a significant role in systemic inflammation. It has some extragastrointestinal manifestations like endocrine diseases. In this study, we aimed to compare the prevalence of HP infection in diabetic and nondiabetic individuals.

MATERIALS AND METHODS

In this cross-sectional study, 218 nondiabetic and 211 diabetic patients referring to Shahid Beheshti Hospital of Qom between March 2013 and 2014 were studied. The patients were divided into two HP(+) and HP(-) groups based on serological immunoglobulin G antibody against HP and the association between diabetes, and HP infection was evaluated. Data were analyzed using independent t-tests, Chi-square, Fisher's exact and Mann-Whitney tests.

RESULTS

The prevalence of HP seropositive was 65.9% versus 50.5% in diabetic and nondiabetics, respectively, and the difference was statistically significant (P = 0.001).

CONCLUSIONS

This study showed a higher prevalence of HP infection in diabetic patients.

Ureteral involvement and diabetes increase the risk of subsequent bladder recurrence after nephroureterectomy for upper urinary tract urothelial carcinoma

OBJECTIVES

To investigate the prognostic factors for bladder recurrence after radical nephroureterectomy (RNU) in patients with upper urinary tract urothelial carcinoma (UUT-UC).

METHODS

From 1994 to 2012, 695 patients with UUT-UC treated with RNU were enrolled in National Taiwan University Medical Center. Among them, 532 patients with no prior bladder UC history were recruited for analysis. We assessed the impact of potentially prognostic factors on bladder recurrence after RNU.

RESULTS

The median follow-up period was 47.8 months. In the Cox model, ureteral involvement and diabetes mellitus (DM) were significantly associated with a higher bladder recurrence rate in the multivariate analysis (hazard ratio [HR]: 1.838; P = 0.003 and HR: 1.821; P = 0.010, resp.). In the Kaplan-Meier analysis, DM patients with concomitant ureteral UC experienced about a threefold increased risk of bladder recurrence as compared to those without both factors (HR: 3.222; P < 0.001). Patients with either of the two risk factors experienced about a twofold increased risk as compared to those without both factors (with DM, HR: 2.184, P = 0.024; with ureteral involvement, HR: 2.006, P = 0.003).

CONCLUSIONS

Ureteral involvement and DM are significantly related to bladder recurrence after RNU in patients with UUT-UC.

Helicobacter pylori: the balance between a role as colonizer and pathogen

The isolation of Helicobacter pylori from the human stomach produced significant changes in how gastroenterologists, immunologists, epidemiologists, pathologists and microbiologists have approached gastro-duodenal diseases in the last half of the XX century. However, research of this organism has progressed greatly in the first decade of this century, evidence suggest that H. pylori is associated with disease only in humans older than 40 years, while, the lack of H. pylori colonization is associated with the emergence of new diseases, particularly in younger individuals. These differing effects of H. pylori colonization have created two contrasting concepts: the 'bad' and the 'good' Helicobacter. Following from renewed interest in the normal human microbiome, we need to reconsider our definitions and perhaps recognize that H. pylori might be a normal member of the human gastric microbiome in ancient humans that gradually, as results of the improvement in our environment, is disappearing.

Helicobacter pylori and extragastric diseases

While Helicobacter pylori infection was initially revealed to be associated only with some gastroduodenal diseases, further studies have shown its possible role in several extragastric diseases. For idiopathic thrombocytopenic purpura, sideropenic anemia, and vitamin B12 deficiency, the diagnosis of H. pylori infection is recommended, and there are many other conditions such as cardiovascular, neurological, dermatological, and respiratory diseases in which H. pylori may possibly play a role. Interestingly, a potential role has also been described for GI neoplastic diseases, including colorectal and pancreatic cancer. Different mechanisms of action have been proposed, ranging from the induction of a low grade inflammatory state to the occurrence of molecular mimicry mechanisms. This review summarizes the results of the most relevant studies published on this topic over the last year.