The prevalence of Helicobacter pylori in obese subjects

Frequency of periodontal pathogens and Helicobacter pylori in the mouths and stomachs of obese individuals submitted to bariatric surgery: a cross-sectional study

OBJECTIVES

This cross-sectional study compared the frequency of oral periodontopathogens and H. pylori in the mouths and stomachs of obese individuals with or without periodontitis submitted to bariatric surgery.

MATERIAL AND METHODS

One hundred and fifty-four men and women aged 18-65 were conveniently distributed into four groups. Two groups were composed of individuals who underwent bariatric surgery with (BP) (n=40) and without (BNP) (n=39) periodontitis and two obese control groups with (CP) (n=35) and without (CNP) (n=40) periodontitis. The oral pathogens Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Parvimonas micra, Treponema denticola, Tannerella forsythia, Campylobacter rectus, and Helicobacter pylori were detected by a polymerase chain reaction technique using saliva, tongue and stomach biopsy samples.

RESULTS

Statistical analysis demonstrated that periodontopathogens were highly frequent in the mouth (up to 91.4%). In the bariatric surgically treated group, orally, P. gingivalis, T. denticola and T. forsythia were more frequent in periodontitis, while C. rectus was more frequent in non-periodontitis subjects. Stomach biopsies also revealed the high frequency of five oral species in both candidates for bariatric surgery (91.6%) and the bariatric (83.3%) groups. H. pylori was frequently detected in the mouth (50.0%) and stomach (83.3%). In the stomach, oral species and H. pylori appeared in lower frequency in the bariatric group.

CONCLUSIONS

Obese individuals showed high frequencies of periodontopathogens and H. pylori in their mouths and stomachs. Bariatric surgery showed an inverse microbial effect on oral and stomach environments by revealing higher oral and lower stomach bacterial frequencies.

Impact of Helicobacter pylori Immunoglobulin G Levels and Atrophic Gastritis Status on Risk of Metabolic Syndrome

Background

Helicobacter pylori (HP) infection is implicated in gastric and extra-gastric diseases. While gastritis-related chronic inflammation represents a known trigger of metabolic disturbances, whether metabolic syndrome (MetS) is affected by gastritis status remains unclear. We aimed to clarify the effect of HP-related gastritis on the risk of MetS.

Materials and Methods

We retrospectively enrolled patients undergoing screening for MetS between 2014 and 2015. Investigations included HP-specific immunoglobulin G (IgG) antibody assays to detect HP infection, and serum pepsinogen assays to evaluate atrophic gastritis status. The risk of MetS was evaluated via multiple logistic regression analyses with two covariates: serum HP infection status (IgG levels) and atrophic gastritis status (two criteria were applied; pepsinogen I/II ratio < 3 or both pepsinogen I levels ≤ 70 μg/L and pepsinogen I/II ratio < 3).

Results

Of 1,044 participants, 247 (23.7%) were HP seropositive, and 62 (6.0%) had MetS. HP seronegative and seropositive patients had similar risks of MetS. On the other hand, AG (defined in terms of serum PG I/II <3) was significant risk of MetS (OR of 2.52 [95% CI 1.05–7.52]). After stratification according to HP IgG concentration, patients with low HP infection status had the lowest MetS risk (defined as an odds ratio [OR] adjusted for age, sex, smoking, drinking and physical activity status). Taking this result as a reference, patients with negative, moderate, and high HP infection status had ORs (with 95% confidence intervals [CI]) of 2.15 (1.06–4.16), 3.69 (1.12–16.7), and 4.05 (1.05–26.8).

Conclusions

HP-associated gastritis represents a risk factor for MetS. Research should determine why low and not negative HP infection status is associated with the lowest MetS risk.

The oesophageal microbiome: an unexplored link in obesity-associated oesophageal adenocarcinoma

The influence of diets rich in saturated fats and simple sugars on the intestinal microbiota plays a central role in obesity. Being overweight or obese predisposes individuals to several diseases including oesophageal adenocarcinoma (OAC), which develops through a cascade of events starting with gastro-oesophageal reflux disease, progressing to Barrett's oesophagus (BO), and then OAC. A range of mechanisms for the increased risk of OAC in obese individuals have been proposed; however, a role for the oesophageal microbiota has been largely ignored. This is despite the fact that it is clear that the composition of the oesophageal microbiota shifts with the development of OAC. Given the well-established impact that unhealthy diets have on the intestinal microbiota, it is plausible that exposure to unhealthy foods, and the ensuing obesity, would result in an imbalance in the oesophageal microbiota. It is also likely that these changes may mimic the changes observed in the intestinal microbiota (i.e. increase in short-chain fatty acid (SCFA) producers and bile acid biosynthesis). The modulation of SCFAs and bile acids in the oesophagus by diet could promote the transdifferentiation from squamous to intestinal-like columnar cells observed in BO, given that intestinal cells proliferate in the presence of SCFAs.

Influence of Helicobacter pylori Infection on Metabolic Syndrome in Old Chinese People

Background. H. pylori infection is one of the most common chronic infectious inflammatory diseases worldwide and is also a risk factor for atherosclerosis. Patients with metabolic syndrome are known to be at increased risk for atherosclerosis. The aim of our study was to assess the effects of H. pylori infection on serum lipids, body mass index (BMI), and metabolic syndrome in old Chinese people. Material and Method. A total of 191 (133 males and 58 females, aged 73.19 ± 11.03 years) people who had gastroscopy examination in our hospital were divided into H. pylori-positive group (n = 80) and H. pylori-negative group (n = 111). H. pylori infection was diagnosed by rapid urease test. Results. Patients with H. pylori infection had higher BMI and fasting glucose levels and incidence of metabolic syndrome (p < 0.01). It was found that BMI (p < 0.01, OR 74.469), H. pylori infection (p < 0.01, OR 5.427), total cholesterol (p < 0.01, OR 15.544), and diabetes mellitus (p < 0.01, OR 23.957) were significantly associated with the risk of metabolic syndrome by binary logistic regression analysis. Conclusions. Patients with H. pylori infection had higher BMI and fasting glucose levels and had incidence of metabolic syndrome.

The Association between Helicobacter pylori Infection and Body Weight among Children

PURPOSE

We performed to reveal the association between the Helicobacter pylori infection and body weight among children.

METHODS

Out retrospective study included patients who underwent the H. pylori immunoglobulin G testing at Konyang University Hospital between March 2011 and June 2014. These patients were classified as seropositive (28 boys, 27 girls; mean age: 9.89±3.28 years) or seronegative (55 boys, 54 girls; mean age: 9.84±3.02 years). Next, we compared various characteristics between the seropositive and negative groups, as well as between obese children (body weight ≥90th percentile) and non-obese children (body weight <90th percentile). Furthermore, we compared the change in body weight after 2 months of treatment with amoxicillin, clarithromycin and omeprazole among the 55 seropositive children (14 treated children and 41 non-treated children).

RESULTS

There were no differences in the weights and laboratory data for the 55 seropositive children and 109 seronegative children (weight; 40.96±18.11 kg vs. 36.85±13.72 kg, respectively; p=0.14). And, there was no difference in the prevalence of H. pylori infection among the 29 obese and 135 non-obese children (p=0.581). However, after 2 months of eradication, the 14 treated patients exhibited a significant weight gain (+0.91±0.52 kg), compared to the 41 non-treated patients (-0.29±1.16 kg, p=0.025).

CONCLUSION

Our findings present that obesity was not associated with the H. pylori infection, although H. pylori eradication led to significant increase in body weight.

Chronic Gastritis in Morbidly Obese Patients with Sleeve Gastrectomy

INTRODUCTION

Obesity is a condition that has significant impact on public health. Recent exciting studies have linked chronic gastritis and H. pylori infection to obesity. Chronic gastritis has shown increased prevalence in obesity, more particularly H. pylori-related gastritis. This study aimed to determine the prevalence of chronic gastritis in morbidly obese patients who were subjected to sleeve gastrectomy, with focus on H. pylori-related gastritis. The aim was to demonstrate any influence on chronic gastritis of the surgical procedure or its post-operative course.

METHODS

One hundred six morbidly obese patients were subjected to vertical sleeve gastrectomy in King Abdulaziz University Hospital (KAUH) from March 2014 to April 2015. After full pre-operative preparation, sleeve gastrectomy was carried out, followed by histological examination of the specimen to view the chronic gastritis and H. pylori-related cases. All epidemiological data of the patients, including age, gender, body mass index (BMI), as well as mean operative time, length of hospital stay, and post-operative complications were documented and analyzed by IBM-SPSS version 22.

RESULTS

Female patients presented the higher prevalence, i.e., 66% among the group of patients with sleeve resection, while 33% had chronic gastritis and 8.5% had H. pylori-related gastritis.

CONCLUSION

This study highlights the high prevalence of chronic gastritis in morbidly obese patients with reference to the high incidence of H. pylori-related gastritis among them, however no relationship was found between this infection and the post-operative outcome.

Interaction of obesity and infections

There is evidence that certain infections may induce obesity. Obese persons may also have more severe infections and have compromised response to therapies. The objective of this study is to review the available literature identifying infections that potentially contribute to greater body mass index (BMI) and differential responses of overweight and obese persons to infections. A systematic literature review of human studies examining associations between infections and weight gain, differential susceptibility, severity, and response to prevention and treatment of infection according to BMI status (January 1980-July 2014) was conducted. Three hundred and forty-three studies were eligible for inclusion. Evidence indicated that viral infection by human adenovirus Ad36 and antibiotic eradication of Helicobacter pylori were followed by weight gain. People who were overweight or obese had higher susceptibility to developing post-surgical infections, H1N1 influenza and periodontal disease. More severe infections tended to be present in people with a larger BMI. People with a higher BMI had a reduced response to vaccinations and antimicrobial drugs. Higher doses of antibiotics were more effective in obese patients. Infections may influence BMI, and BMI status may influence response to certain infections, as well as to preventive and treatment measures. These observations have potential clinical implications.

Obesity and Infection: Reciprocal Causality

Associations between different infectious agents and obesity have been reported in humans for over thirty years. In many cases, as in nosocomial infections, this relationship reflects the greater susceptibility of obese individuals to infection due to impaired immunity. In such cases, the infection is not related to obesity as a causal factor but represents a complication of obesity. In contrast, several infections have been suggested as potential causal factors in human obesity. However, evidence of a causal linkage to human obesity has only been provided for adenovirus 36 (Adv36). This virus activates lipogenic and proinflammatory pathways in adipose tissue, improves insulin sensitivity, lipid profile and hepatic steatosis. The E4orf1 gene of Adv36 exerts insulin senzitizing effects, but is devoid of its pro-inflammatory modalities. The development of a vaccine to prevent Adv36-induced obesity or the use of E4orf1 as a ligand for novel antidiabetic drugs could open new horizons in the prophylaxis and treatment of obesity and diabetes. More experimental and clinical studies are needed to elucidate the mutual relations between infection and obesity, identify additional infectious agents causing human obesity, as well as define the conditions that predispose obese individuals to specific infections.

From the stomach to other organs: Helicobacter pylori and the liver

Many recent studies have examined the importance of Helicobacter pylori (H. pylori) infection in the pathogenesis of the diseases outside the stomach and explored the significance of this bacterium in the pathogenesis of some metabolic and cardiovascular diseases. Recent studies have provided evidence that H. pylori is also involved in the pathogenesis of some liver diseases. Many observations have proved that H. pylori infection is important in the development of insulin resistance, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, liver fibrosis and cirrhosis. The worsening of liver inflammation of different origins also occurs during H. pylori infection. Some studies have indicated that H. pylori infection induces autoimmunological diseases in the liver and biliary tract. The potential significance of this bacterium in carcinogenesis is unclear, but it is within the scope of interest of many studies. The proposed mechanisms through which H. pylori impacts the development of hepatobiliary diseases are complex and ambiguous. The importance of other Helicobacter species in the development of hepatobiliary diseases is also considered because they could lead to the development of inflammatory, fibrotic and necrotic injuries of the liver and, consequently, to hepatocellular carcinoma. However, many contrary viewpoints indicate that some evidence is not convincing, and further studies of the subject are needed. This review presents the current knowledge about the importance of H. pylori in the pathogenesis of liver and in biliary diseases.

Adenovirus 36 and Obesity: An Overview

There is an epidemic of obesity starting about 1980 in both developed and undeveloped countries definitely associated with multiple etiologies. About 670 million people worldwide are obese. The incidence of obesity has increased in all age groups, including children. Obesity causes numerous diseases and the interaction between genetic, metabolic, social, cultural and environmental factors are possible cofactors for the development of obesity. Evidence emerging over the last 20 years supports the hypothesis that viral infections may be associated with obesity in animals and humans. The most widely studied infectious agent possibly linked to obesity is adenovirus 36 (Adv36). Adv36 causes obesity in animals. In humans, Adv36 associates with obesity both in adults and children and the prevalence of Adv36 increases in relation to the body mass index. In vivo and in vitro studies have shown that the viral E4orf1 protein (early region 4 open reading frame 1, Adv) mediates the Adv36 effect including its adipogenic potential. The Adv36 infection should therefore be considered as a possible risk factor for obesity and could be a potential new therapeutic target in addition to an original way to understand the worldwide rise of the epidemic of obesity. Here, the data indicating a possible link between viral infection and obesity with a particular emphasis to the Adv36 will be reviewed.

Helicobacter Pylori Infection is Positively Associated with Metabolic Syndrome in Taiwanese Adults: a Cross-Sectional Study

BACKGROUND

Helicobacter pylori infection and metabolic syndrome have been reported to be positively associated. However, only a few studies have focused on this issue, and H. pylori serum antigen was used to diagnose infection in most of them. We aimed to investigate the association between metabolic syndrome factors and H. pylori infection, as diagnosed via a (13)C-urea breath test.

MATERIALS AND METHODS

This cross-sectional study consisted of 3578 subjects (18-64 years old) enrolled from one health management center between 2008 and 2013. H. pylori infection was defined as a positive urea breath test. The risk of metabolic syndrome from H. pylori infection was assessed using a multiple logistic regression model.

RESULTS

The prevalence of the H. pylori was similar in both genders (20.6% in men and 19.7% in women). H. pylori -infected participants had significantly higher body mass index, fasting glucose, low-density lipoprotein, and triglycerides, and lower high-density lipoprotein (p < 0.05), than uninfected ones (p < 0.05). The prevalence of metabolic syndrome was higher in H. pylori -infected subjects than uninfected ones (men: 12.4% vs. 7.4%, p < 0.001; women: 7.4% vs. 2.5%, p < 0.001). Furthermore, H. pylori infection prevalence increased with metabolic score (P for trend <0.001, both sexes). Moreover, the association between metabolic syndrome and UBT positivity was significant in females (OR 1.91, 95% CI:1.03-3.53), but only borderline significant in males (OR 1.38, 95% CI: 0.97-1.95).

CONCLUSION

H. pylori infection is positively associated with metabolic syndrome, especially in females. The causal relationship between H. pylori infection and metabolic syndrome warrants further investigation.

Prevalence of Helicobacter pylori infection and its relation with body mass index in a Chinese population

BACKGROUND

Helicobacter pylori infection is highly prevalent worldwide. The association between obesity and H. pylori infection is controversial in the literature. This study aims to investigate the prevalence of H. pylori infection and its relation with body mass index (BMI) in a Chinese population.

MATERIALS AND METHODS

A cross-sectional study was performed among adults who underwent health checkups at the First Affiliated Hospital, College of Medicine, Zhejiang University in 2013. The prevalence of H. pylori infection was examined by (13)C urea breath tests, and the association between prevalence of H. pylori infection and BMI was analyzed.

RESULTS

Of the 8820 participants enrolled, 3859 (43.8%) were positive for H. pylori infection. H. pylori-positive participants had a more unfavorable metabolic profile than H. pylori-negative participants. Overweight/obese participants showed a higher prevalence of H. pylori infection than that of lean participants, and a positive linear correlation between BMI and prevalence of H. pylori infection was observed. Both unadjusted and adjusted analysis revealed that BMI was significantly associated with risk factors of H. pylori infection.

CONCLUSIONS

Our results showed that BMI was significantly and positively associated with H. pylori infection, and a high BMI was associated with an increased risk of the infection.

Influence of Helicobacter pylori infection on metabolic parameters and body composition of dyslipidemic patients

Helicobacter pylori infection may contribute to the development of extra-gastroduodenal diseases. The aim of this study was to explore whether this infection could influence metabolic parameters and body composition of dyslipidemic patients. In an 8-month period, 155 patients attended our clinic; 110 patients (48 men and 62 women, age 35-55 years) fulfilled inclusion criteria. Metabolic parameters were determined by routine tests and body composition by anthropometry and bioelectrical impedance analysis. The H. pylori and CagA infectious status were examined serologically. Sixty-one patients (55.4%) had serum antibodies to H. pylori and 30 infected patients (49.1%) had anti-CagA antibodies. The mean percentage of fat mass and level of high-density protein cholesterol in seropositive patients were significantly lower than those measured in seronegative ones (P = 0.008 and P < 0.001, respectively). The mean glucose concentration in patients with anti-H. pylori serum IgG was significantly higher than in uninfected patients (P = 0.021). No significant difference was observed regarding the other parameters. The CagA status did not influence any of the considered parameters. Our results are in agreement with those of other studies; however, the level of concordance of results reported in the various publications on this topic is very low, presumably from differences concerning the age, alimentary habits and possible presence of different pathologies in the groups studied. The most plausible hypothesis for the observed alterations may exist in the low-grade systemic inflammatory status of infected individuals, which may influence the fat turnover and support the insulin resistance with consequent alteration of glucose metabolism.

Role of Helicobacter pylori infection on nutrition and metabolism

Helicobacter pylori (H. pylori) is a gram-negative pathogen that is widespread all over the world, infecting more than 50% of the world’s population. It is etiologically associated with non-atrophic and atrophic gastritis, peptic ulcer and shows a deep association with primary gastric B-cell lymphoma and gastric adenocarcinoma. Recently, the medical research focused on the modification of the gastric environment induced by H. pylori infection, possibly affecting the absorption of nutrients and drugs as well as the production of hormones strongly implicated in the regulation of appetite and growth. Interestingly, the absorption of iron and vitamin B12 is impaired by H. pylori infection, while infected subjects have lower basal and fasting serum levels of ghrelin and higher concentration of leptin compared to controls. Since leptin is an anorexigenic hormone, and ghrelin stimulates powerfully the release of growth hormone in humans, H. pylori infection may finally induce growth retardation if acquired very early in the childhood and in malnourished children. This review is focused on the nutritional effects of H. pylori infection, such as the reduced bioavailability or the malabsorbption of essential nutrients, and of gastrointestinal hormones, as well as on the relationship between H. pylori and the metabolic syndrome.

Does helicobacter pylori infection have influence on outcome of laparoscopic sleeve gastrectomy for morbid obesity?

INTRODUCTION

Among the surgical procedures for treatment of morbid obesity, laparoscopic sleeve gastrectomy has known widespread diffusion in the last years, although it is not free from significant morbidity rates. Aim of this work is to evaluate the incidence of Helicobacter pylori (HP) infection on the postoperative outcome of patients undergoing laparoscopic sleeve gastrectomy.

METHODS

Between January 2008 and December 2013, 184 patients (65 males, 119 females), mean age 35.8 ± 5.7 years, affected with morbid obesity, mean BMI 46.6 ± 6.7, underwent laparoscopic sleeve gastrectomy. All the specimens at the end of the operation were analysed by the same pathologist. Histological grading was based on the Sidney classification.

RESULTS

Seventy-two of the patients (39.1%) were HP positive, while 112 (60.9%) were negative. No significant differences were observed between the HP+ and HP- group in terms of age, sex, weight, BMI, incidence of comorbidities and duration of follow-up. All the operations were completed via laparoscopic approach. No mortality was observed. Postoperative complications occurred in 5 patients (2.7%): three leaks (1.6%), all in the HP- group and two bleedings (1.1%), one in the HP+ and one in the HP- group. In two cases a reintervention was necessary. No significant differences were observed in the morbidity rates between the two groups. Overall mean excess weight loss at 6 months, 12 months and 24 months was respectively 47.4 ± 11.3%, 61.1 ± 12.4% and 68.4 ± 13.5%, with no significant differences between the HP+ and HP- groups.

CONCLUSIONS

HP infection seems not to influence postoperative outcome of patients operated of laparoscopic sleeve gastrectomy.

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.

Socioeconomic status, personal habits, and prevalence of Helicobacter pylori infection in the inhabitants of Lanyu

BACKGROUND/PURPOSE

Lanyu Island is a closed environment inhabited by the Yami people, Taiwan's smallest and most primitive tribe. This study assessed the prevalence and risk factors of Helicobacter pylori infection among Lanyu Island residents.

METHODS

A cross-sectional study was conducted among the inhabitants of Lanyu Island, using the (13)C urea breath test to determine the prevalence of H. pylori. All study participants completed a form requesting demographic data and anthropometric measurements and a questionnaire evaluating socioeconomic characteristics and personal habits. Multiple logistic regression analyses were used to identify independent factors of H. pylori infections, and a two-sided p < 0.05 was considered significant.

RESULTS

Among 796 participants, the mean age was 45 ± 13.2 years, with a range of 12-89 years. The overall prevalence of H. pylori infection was 72.1%, and there was no significant difference between genders. The H. pylori-infected group contained higher proportions of Yami people, married individuals, as well as higher rates of alcohol consumption and betel chewing, but lower family incomes and education levels. Multiple logistic models found that Yami ethnicity [odds ratio (OR) = 2.567, 95% confidence interval (CI): 1.344-4.905], alcohol consumption (OR = 1.641, 95% CI: 1.151-2.341), and marital status (OR = 1.779, 95% CI: 1.043-3.032] were associated with H. pylori infection.

CONCLUSION

This cross-sectional study identified a high prevalence of H. pylori infection on Lanyu Island. When investigating H. pylori infection status in a closed environment, such as Lanyu Island, it is important to consider all factors relating to the host population, including environment and lifestyle.

Gastrointestinal morbidity in obesity

Obesity is a complex disease that results from increased energy intake and decreased energy expenditure. The gastrointestinal system plays a key role in the pathogenesis of obesity and facilitates caloric imbalance. Changes in gastrointestinal hormones and the inhibition of mechanisms that curtail caloric intake result in weight gain. It is not clear if the gastrointestinal role in obesity is a cause or an effect of this disease. Obesity is often associated with type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Obesity is also associated with gastrointestinal disorders, which are more frequent and present earlier than T2DM and CVD. Diseases such as gastroesophageal reflux disease (GERD), cholelithiasis, or nonalcoholic steatohepatitis are directly related to body weight and abdominal adiposity. Our objective is to assess the role of each gastrointestinal organ in obesity and the gastrointestinal morbidity resulting in those organs from the effects of obesity.

Helicobacter pylori infection in obesity and its clinical outcome after bariatric surgery

The present review summarizes the prevalence and active clinical problems in obese patients with Helicobacter pylori (H. pylori) infection, as well as the outcomes after bariatric surgery in this patient population. The involvement of H. pylori in the pathophysiology of obesity is still debated. It may be that the infection is protective against obesity, because of the gastritis-induced decrease in production and secretion of the orexigenic hormone ghrelin. However, recent epidemiological studies have failed to show an association between H. pylori infection and reduced body mass index. H. pylori infection might represent a limiting factor in the access to bariatric bypass surgery, even if high-quality evidence indicating the advantages of preoperative H. pylori screening and eradication is lacking. The clinical management of infection is complicated by the lower eradication rates with standard therapeutic regimens reported in obese patients than in the normal-weight population. Prospective clinical studies to ameliorate both H. pylori eradication rates and control the clinical outcomes of H. pylori infection after different bariatric procedures are warranted.

Potential role of Helicobacter pylori infection in nonalcoholic fatty liver disease

Accumulating evidence has implicated Helicobacter pylori (H. pylori) infection in extragastrointestinal diseases, including obesity, type 2 diabetes mellitus, cardiovascular disease, and liver disease. Recently, there has been a special focus on H. pylori infection as a risk factor for the development of nonalcoholic fatty liver disease (NAFLD). NAFLD is currently considered to be the most common liver disorder in western countries, and is rapidly becoming a serious threat to public health. The mechanisms of pathogenesis underlying NAFLD remain unclear at present and therapeutic options are limited. The growing awareness of the role of H. pylori in NAFLD is thus important to aid the development of novel intervention and prevention strategies, because the eradication of H. pylori is easy and much less expensive than long-term treatment of the other risk factors. H. pylori infection is involved in the pathogenesis of insulin resistance (IR), which is closely linked with NAFLD. It provides a new insight into the pathogenesis of NAFLD. This review probes the possible relationship between H. pylori and NAFLD, from the perspective of the potential mechanism of how H. pylori infection brings about IR and other aspects concerning this correlation.

Helicobacter pylori infection in Europe: current perspectives

There is a commonly held perception that Helicobacter pylori related diseases are declining, however these are still associated with a high risk of morbidity and mortality. In recent years worrying themes have emerged such as increasing levels of antibiotic resistance and falling cure rates which illustrate there is no room for complacency with respect to H. pylori. In addition there are many significant issues which have not been elucidated regarding the role played by H. pylori in very serious pathologies such as gastric and esophageal cancer and other more benign disorders common in the developed world such as gastroesophageal reflux disease, functional dyspepsia and perhaps obesity which carry a significant impact both economically and as regards to symptoms. Future guidelines aimed at European practitioners and patients will need to address the questions raised by these issues as well as the more familiar areas such as constituents and duration of therapy.

Gastric Helicobacter pylori infection is associated with adverse metabolic traits in severely obese subjects

OBJECTIVE

Asian studies have reported on an association of Helicobacter pylori (Hp) infection with insulin resistance (IR) in normal-weight subjects. Whether such an association likewise exists in European subjects with severe obesity was questioned.

DESIGN AND METHODS

To address this question, 370 severely obese patients from our database were identified, who had undergone a gastroscopy with a histological examination of gastric mucosal biopsies and a concurrent assessment metabolic blood parameters as a standard examination before bariatric surgery.

RESULTS

Seventy-five (20.3%) of the subjects displayed a histologically proven Hp infection (Hp+). Sex distribution, age, and body mass index of Hp+ subjects did not differ from that of the subjects with no Hp infection (Hp-; all P > 0.293), but Hp+ subjects were significantly smaller (P = 0.006). Fasting glucose, insulin, high-sensitive C reactive protein, and alanine aminotransferase levels as well as calculated indices of IR (i.e., HOMA-IR, QUICKI) did not differ between Hp+ and Hp- subjects (all P > 0.42). However, Hp+ subjects showed significantly higher triglyceride levels and a higher total chloesterol-to-HDL ratio but lower sex-hormone binding globulin (SHGB) levels than Hp- subjects (all P ≤ 0.05).

CONCLUSION

While our results obtained in European severely obese patients do not provide evidence for an enhanced IR state associated with gastric Hp infection, they suggest that the presence of the bacterium in gastric biopsies is associated with an adverse lipid profile and reduced SHGB levels.

Correlation between Helicobacter pylori infection and hemoglobin A1c expression

Helicobacter pylori (H. pylori) is a gram-negative bacterium that is closely related with the pathogenesis of chronic gastritis, peptic ulcer, gastric carcinoma as well as many extra-gastrointestinal tract diseases such as coronary heart disease, iron deficiency anemia, idiopathic thrombocytopenic purpura, and diabetes mellitus (DM). Hemoglobin A1c (HbA1c) level is useful in diagnosing and monitoring DM. Recent studies showed that H. pylori is involved in the up-regulation of HbA1c level in DM patients through modulating the expression of leptin and ghrelin, whose interactions affect obesity, insulin sensitivity, glucose homeostasis and DM. Further studies on the association between H. pylori infection and HbA1c will certainly provide new prospects for early diagnosis and treatment of H. pylori-related DM and its complications.

Extragastrointestinal manifestations of Helicobacter pylori infection: facts or myth? A critical review

Helicobacter pylori (H. pylori) infection is reported to be associated with many extragastrointestinal manifestations, such as hematological diseases [idiopathic thrombocytopenic purpura (ITP) and unexplained iron deficiency anemia (IDA)], cardiovascular diseases (ischemic heart diseases), neurological disorders (stroke, Parkinson's disease, Alzheimer's disease), obesity and skin disorders. Among these, the best evidence so far is in ITP and unexplained IDA, with high-quality studies showing the improvement of IDA and ITP after H. pylori eradication. The evidence of its association with coronary artery disease is weak and many of the results may be erroneous. The role of H. pylori infection in affecting serum leptin and ghrelin levels has attracted a lot of attention recently and available data to date have been conflicting. There have also been many uncontrolled, small sample studies suggesting an association between H. pylori infection and neurological disorders or chronic urticaria. However, more studies are required to clarify such proposed causal links.

Obesity and the risk and outcome of infection

The interactions between obesity and infectious diseases have recently received increasing recognition as emerging data have indicated an association between obesity and poor outcome in pandemic H1N1 influenza infection. Obesity is an established risk factor for surgical-site infections, nosocomial infections, periodontitis and skin infections. Several studies indicate that acute pancreatitis is more severe in the obese. Data are controversial and limited as regards the association between obesity and the risk and outcome of community-acquired infections such as pneumonia, bacteremia and sepsis and obesity and the course of HIV infection. As the cause-effect relationship between obesity and infection remains obscure in many infectious diseases, further studies are warranted. The consequences of obesity may have substantial effects on the global burden of infectious diseases.

A genome-wide association meta-analysis identifies new childhood obesity loci

Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made in establishing genetic influences on common early-onset obesity. We performed a North American, Australian and European collaborative meta-analysis of 14 studies consisting of 5,530 cases (≥95th percentile of body mass index (BMI)) and 8,318 controls (<50th percentile of BMI) of European ancestry. Taking forward the eight newly discovered signals yielding association with P < 5 × 10(-6) in nine independent data sets (2,818 cases and 4,083 controls), we observed two loci that yielded genome-wide significant combined P values near OLFM4 at 13q14 (rs9568856; P = 1.82 × 10(-9); odds ratio (OR) = 1.22) and within HOXB5 at 17q21 (rs9299; P = 3.54 × 10(-9); OR = 1.14). Both loci continued to show association when two extreme childhood obesity cohorts were included (2,214 cases and 2,674 controls). These two loci also yielded directionally consistent associations in a previous meta-analysis of adult BMI(1).

A framework for identification of infections that contribute to human obesity

WHO has declared obesity to be a global epidemic. Obesity management strategies mainly target behavioural components of the disorder, but are only marginally effective. A comprehensive understanding of the causative factors of obesity might provide more effective management approaches. Several microbes are causatively and correlatively linked with obesity in animals and human beings. If infections contribute to human obesity, then entirely different prevention and treatment strategies and public health policies could be needed to address this subtype of the disorder. Ethical reasons preclude experimental infection of human beings with candidate microbes to unequivocally determine their contribution to obesity. As an alternative, the available information about the adipogenic human adenovirus Ad36 has been used to create a template that can be used to examine comprehensively the contributions of specific candidate microbes to human obesity. Clinicians should be aware of infectobesity (obesity of infectious origin), and its potential importance in effective obesity management.

Association between HSV1 seropositivity and obesity: data from the National Health and Nutritional Examination Survey, 2007-2008

Background

Herpes simplex virus (HSV) is among the most common sexually transmitted pathogens in the United States and worldwide. HSV has a high incidence of undetected cases. In addition, there is no treatment, and there is a lack of knowledge why disparities among populations exist. Research studies suggest that fat tissue may participate in body's immune responses, and the impact of obesity on susceptibility to HSV1 infection is not clear. The purpose of this study was to examine whether obesity is a risk factor for HSV1 infection using a large sample from the general population.

Methods/Principal Findings

This cross-sectional study used data from the National Health and Examination and Nutritional Examination Survey (NHANES) from 2007–2008. Variables, gender, age, race/ethnicity, marital status, education, poverty level, and diabetes represented potential confounders and were included in analyses. The two-tailed Pearson's chi square, student's t test, and a multiple logistic regression analysis were applied to evaluate associations using a significance value of p≤0.05. Adjusted odds ratios with 95% confidence interval represented the degree of these associations. The prevalence of HSV1 infection in US population between 20 and 49 years old was 60.3% (n = 1,536). In this study, having a BMI classified as the obese group (BMI 30–39.9) was significantly associated with HSV1 infection before [unadjusted OR = 1.74 (95% CI 1.20–2.51), p = 0.006] and after controlling for socio-demographic factors [adjusted OR = 1.50 (95%CI 1.06–2.13)], p = 0.026]. This association was stronger than three already established risk factors of age, female gender, and poverty level.

Conclusions/Significance

This study provides evidence that obesity may play a role in the susceptibility to HSV1 infection. Findings from this study suggest that obesity should be considered when designing preventive measures for HSV1 infection. These results may also explain why some people acquire HSV1 infections and some do not. Further, these findings may justify an increased emphasis on the control and prevention of HSV1 transmission and other pathogens in overweight and obese populations.

The burden of obesity on infectious disease

The world is now experiencing an epidemic of obesity. Although the effects of obesity on the development of metabolic and cardiovascular problems are well studied, much less is known about the impact of obesity on immune function and infectious disease. Studies in obese humans and with obese animal models have repeatedly demonstrated impaired immune function, including decreased cytokine production, decreased response to antigen/mitogen stimulation, reduced macrophage and dendritic cell function, and natural killer cell impairment. Recent studies have demonstrated that the impaired immune response in the obese host leads to increased susceptibility to infection with a number of different pathogens such as community-acquired tuberculosis, influenza, Mycobacterium tuberculosis, coxsackievirus, Helicobacter pylori and encephalomyocarditis virus. While no specific mechanism has been defined for the decreased immune response to infectious disease in the obese host, several obesity-associated changes such as excessive inflammation, altered adipokine signaling, metabolic changes and even epigenetic regulation could affect the immune response. This review will discuss what is currently known about the relationship between obesity and infectious disease.

Extragastric manifestations of Helicobacter pylori infection

The possible role of Helicobacter pylori as a trigger for some extragastric diseases has been largely investigated in the last year. There are, in fact, several studies concerning cardiovascular diseases, neurological disorders, diabetes mellitus, ear and eyes diseases, immunological and hematological disorders, liver and bile tract diseases, gynecological and respiratory tract pathologies. Among them, idiopathic sideropenic anemia and idiopathic thrombocytopenic purpura still remain the extragastric diseases showing the most convincing results. Concerning ischemic heart disease, there are new interesting data playing in favor of the association, even though there are still some open issues to be clarified. For the other diseases, more studies are needed to clarify the reality of the proposed association.

Epidemiology of Helicobacter pylori infection and public health implications

This article summarizes the published literature concerning the epidemiology and public health implications of Helicobacter pylori infection published from April 2009 through March 2010. Prevalence of infection varied between 7 and 87% and was lower in European studies. All retrieved studies examining transmission of infection concluded that spread is from person-to-person. One study collecting stool and vomitus samples from patients with acute gastroenteritis detected H. pylori DNA in 88% of vomitus and 74% of stool samples. Proposed risk factors for infection included male gender, increasing age, shorter height, tobacco use, lower socioeconomic status, obesity, and lower educational status of the parents in studies conducted among children. Decision analysis models suggest preventing acquisition of H. pylori, via vaccination in childhood, could be cost-effective and may reduce incidence of gastric cancer by over 40%. As yet, no country has adopted public health measures to treat infected individuals or prevent infection in populations at risk.

Obesity and left ventricular assist device driveline exit site infection

Driveline exit site (DLES) infection is a persistent problem among the left ventricular assist device (LVAD) patients. This study investigated the relationship between obesity and DLES infection. Records of LVAD patients at two institutions from January 1999 to January 2009 were queried. Results were analyzed using t tests. Those with LVAD support > or =90 days were included. The body mass index (BMI) of each patient was measured at the time of implant and at the conclusion of LVAD support or currently, if the patient was ongoing. Other data included preimplant age, ejection fraction, blood urea nitrogen, creatinine, diabetes, New York Heart Association class, pulmonary capillary wedge pressure, VO2 max, and inotrope therapy. The 118 patients who qualified for the study were placed in an infection group (n = 36) or in the control group (n = 82). Both groups had similar preimplant characteristics. Variables with differences statistically significant between the groups included duration of LVAD support, indication for support, device type, and BMI. Patients who developed DLES infections had a significantly higher BMI and continued weight gain over the course of LVAD therapy compared with the control group. Although this association requires further study, implications for clinical practice may include the provision of nutrition and exercise counseling for patients undergoing LVAD therapy, especially if overweight. These results may warrant increased measures to prevent and treat infection in the preimplant and postimplant periods.