The prevalence of Helicobacter pylori infection in the Netherlands

Risk of Cancers Proximal to the Colon in Fecal Immunochemical Test Positive Screenees in a Colorectal Cancer Screening Program

BACKGROUND & AIMS

In more than half of the colorectal cancer screening participants with a positive fecal immunochemical test (FIT) result, no advanced neoplasia (AN) is detected at colonoscopy. The positive FIT result could also be generated by cancers located proximal to the colon: upper gastrointestinal, oral cavity, nose, and throat cancers. We evaluated screenees' risk of being diagnosed with a cancer proximal to the colon within the 3 years and compared risks between those with a positive vs those with a negative FIT.

METHODS

Data of Dutch colorectal cancer screening participants who underwent biennial FIT-based screening 2014-2018 were collected from the national screening database and linked to the National Cancer Registry. Screenees were classified into 3 groups: FIT-positives with AN (FIT+/AN+), FIT-positives without AN (FIT+/AN-), and FIT-negatives (FIT-). We compared the cumulative incidence of cancers proximal to the colon in each group 3 years after FIT. A Cox regression analysis with left truncation and right censoring, using FIT positivity as time-dependent variable and stratified for sex, was performed to compare the hazard of cancers proximal to the colon in participants who were FIT-positive vs FIT-negative.

RESULTS

Three-year cumulative incidence of cancers proximal to the colon in FIT+/AN+ (n = 65,767), FIT+/AN- (n = 50,661), and FIT- (n = 1,831,647) screenees was 0.7%, 0.6%, and 0.4%, respectively (P < .001). FIT-positives were older and more frequently male than FIT-negatives (P < .001). Significantly more cancers proximal to the colon were detected among FIT-positives (P < .001; hazard ratio, 1.55; 95% CI, 1.44-1.67).

CONCLUSION

FIT-positive screenees were at significantly increased risk of being diagnosed with a cancer proximal to the colon within 3 years after FIT, although the 3-year cumulative incidence was still less than 1%.

Low Prevalence of HSV-1 and Helicobacter pylori in HNSCC and Chronic Tonsillitis Patients Compared to Healthy Individuals

Recent studies identified viral and bacterial factors, including HSV-1 and H. pylori, as possible factors associated with diseases such as chronic tonsillitis and cancers, including head and neck squamous cell carcinoma (HNSCC). We assessed the prevalence of HSV-1/2 and H. pylori in patients with HNSCC, chronic tonsillitis, and healthy individuals using PCR after DNA isolation. Associations were sought between the presence of HSV-1, H. pylori, and clinicopathological and demographic characteristics and stimulant use. HSV-1 and H. pylori were most frequently identified in controls (HSV-1: 12.5% and H. pylori: 6.3%). There were 7 (7.8%) and 8 (8.6%) patients with positive HSV-1 in HNSCC and chronic tonsillitis patients, respectively, while the prevalence of H. pylori was 0/90 (0%) and 3/93 (3.2%), respectively. More cases of HSV-1 were observed in older individuals in the control group. All positive HSV-1 cases in the HNSCC group were associated with advanced tumor stage (T3/T4). The prevalence of HSV-1 and H. pylori was highest in the controls compared to HNSCC and chronic tonsillitis patients, which indicates that the pathogens were not risk factors. However, since all positive HSV-1 cases in the HNSCC group were observed only in patients with advanced tumor stage, we suggested a possible link between HSV-1 and tumor progression. Further follow-up of the study groups is planned.

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

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

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

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

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

Web-Based Educational Intervention for Patients With Uninvestigated Dyspepsia Referred for Upper Gastrointestinal Tract Endoscopy: A Randomized Clinical Trial

IMPORTANCE

Diagnostic yield of upper gastrointestinal (GI) tract endoscopy for uninvestigated dyspepsia is low, and its clinical implications are limited. There is an unmet need for better strategies to reduce the volume of upper GI tract endoscopic procedures for dyspepsia.

OBJECTIVE

To study the effectiveness of a web-based educational intervention as a tool to reduce upper GI tract endoscopy in uninvestigated dyspepsia.

DESIGN, SETTING, AND PARTICIPANTS

This open-label, multicenter, randomized clinical trial enrolled participants between November 1, 2017, and March 31, 2019, with follow-up 52 weeks after randomization, at 4 teaching hospitals in the Netherlands. Participants included patients with uninvestigated dyspeptic symptoms who were referred for upper GI tract endoscopy by their general health care clinician without prior consultation of a gastroenterologist. A total of 119 patients, aged 18 to 69 years, were included. Patients were excluded if any of the following red flag symptoms were present: (indirect) signs of upper GI tract hemorrhage (hematemesis, melena, hematochezia, or anemia), unintentional weight loss of 5% or higher of normal body weight during a period of 6 to 12 months, persistent vomiting, dysphagia, or jaundice.

INTERVENTIONS

Patients were randomly assigned (1:1) to education (intervention) or upper GI tract endoscopy (control). Education consisted of a self-managed web-based educational intervention, containing information on gastric function, dyspepsia, and upper GI tract endoscopy.

MAIN OUTCOMES AND MEASURES

Difference in the proportion of upper GI tract endoscopy procedures between those who received access to the web-based educational intervention and those who did not at 12 weeks and 52 weeks after randomization, analyzed in the intention-to-treat population. Secondary outcomes included quality of life (Nepean Dyspepsia Index) and symptom severity (Patient Assessment of Gastrointestinal Disorders Symptom Severity Index) measured at baseline and 12 weeks.

RESULTS

Of 119 patients included (median age, 48 years [interquartile range, 37-56 years]; 48 men [40%]), 62 were randomized to web-based education (intervention) and 57 to upper GI tract endoscopy (control). Significantly fewer patients compared with controls underwent upper GI tract endoscopy after using the web-based educational intervention: 24 (39%) vs 47 (82%) (relative risk, 0.46; 95% CI, 0.33-0.64; P < .001). Symptom severity and quality of life improved equivalently in both groups. One additional patient in the intervention group required upper GI tract endoscopy during follow-up.

CONCLUSIONS AND RELEVANCE

Findings of this study indicate that web-based patient education is an effective tool to decrease the need for upper GI tract endoscopy in uninvestigated dyspepsia.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03205319.

Prevalence of Helicobacter pylori Infection in Military Personnel from Northeast China: A Cross-Sectional Study

PURPOSE

Helicobacter pylori infection is an important cause of peptic ulcer disease and gastric cancer. Current knowledge regarding epidemiology of H. pylori infection in military personnel has insufficiently been updated. This cross-sectional study aimed to estimate the prevalence of H. pylori infection in military personnel and to compare the prevalences in military and civilian groups.

PATIENTS AND METHODS

We retrospectively enrolled the subjects who underwent ¹⁴C-urea breath tests at the Department of Gastroenterology of the General Hospital of Northern Theater Command between January 2017 and July 2020. Subjects were divided into military and civilian groups. H. pylori infection and major endoscopic findings were reviewed.

RESULTS

Overall, 23,496 subjects were eligible, including 2282 subjects in the military group and 21,214 subjects in the civilian group. In the overall analysis, the prevalence of H. pylori infection was not significantly different between military and civilian groups (33.9% versus 34.4%, P=0.592). In the population aged 17-25 years, the prevalence of H. pylori infection was significantly higher in the military group than in the civilian group (35.6% versus 25.9%, P=0.001). Both ¹⁴C-UBT and endoscopy were performed in 547 inpatients, including 83 military inpatients and 464 civilian inpatients. There was a significantly higher prevalence of H. pylori in inpatients with peptic ulcer and/or gastric cancer than in those without (65.5% versus 41.4%, P=0.001).

CONCLUSION

Among the adolescent population, H. pylori infection may be more common in military personnel as compared to the civilians. Well-designed prospective studies should be required to validate such a high prevalence and to explain its potential causes.

An Overview of Helicobacter pylori Infection

Helicobacter pylori (H. pylori) represents one of the most widespread bacterial infections globally. Infection causes chronic gastritis and increases the risk of peptic ulcer disease, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. The pioneering discovery of H. pylori by Marshall and Warren in the early 1980s has initiated fervent research into H. pylori as a pathogen ever since. This chapter aims to provide an overview of our understanding of H. pylori infection and its management, with a focus on current options for diagnosis, the challenges associated with H. pylori eradication, and the need for alternative therapeutic strategies based on furthering our understanding of host: H. pylori interactions.

Prevalence and associated risk factors of Helicobacter pylori infection in the Wuwei cohort of north-western China

OBJECTIVES

To evaluate the prevalence of Helicobacter pylori infection and risk factors and to serotype the strains in Wuwei, located in north-western China, which has a high incidence of gastric cancer.

METHODS

Helicobacter pylori infection was analysed in 21 291 adults by ¹⁴ C-urea breath test, and H. pylori antibody were detected in 9183 serum samples by latex immunoturbidimetric method. The correlation of H. pylori infection with demographic-economic, lifestyle factors and medical history among the participants was determined by questionnaire. The antibodies against H. pylori urease, VacA and CagA in serum were determined by dot immunobinding assay.

RESULTS

The infection rate of H. pylori was 53.0%, and 90.1% of strains were type I strains. The H. pylori infection rate was higher among farmers (OR = 1.34, 95% CI: 1.19-1.50) and individuals who had a junior high school or higher education level (OR = 1.10, 95% CI: 1.06-1.15), and was lower in older individuals (OR = 0.86, 95% CI: 0.83-0.90), individuals with high income (OR = 0.93, 95% CI: 0.90-0.95), individuals with a habit of eating quickly (OR = 0.93, 95% CI: 0.87-0.99) and individuals who consumed more fruit and vegetables (OR = 0.90, 95% CI: 0.85-0.95). Individuals with history of cholecystitis/cholecystolithiasis, hypertension and asthma were negatively correlated with H. pylori infection (P < 0.05).

CONCLUSION

The prevalence of H. pylori infection is high in Wuwei. The major prevalent strain is type I strain. Age, education, occupation, household income, consumption of fruit and vegetables, and habit of eating quickly are independent risk factors for H. pylori infection, which is also associated with individuals with a history of extragastric diseases.

Epidemiology and role of Helicobacter pylori virulence factors in gastric cancer carcinogenesis

Infection with Helicobacter pylori is associated with the development of gastric cancer. Although the prevalence of gastric cancer has declined throughout years due to improvement in early screening strategy, mortality due to gastric cancer has not changed. Incidence and mortality due to gastric cancer are higher in developing countries as compared to developed countries. Diagnosis and prognosis of gastric cancer are still poor with patients usually diagnosed with cancer at an advanced stage. Eradication of H. pylori is pertinent for the prevention of gastric cancer. However, the rise in antimicrobial resistance among H. pylori isolates has complicated the prevention strategy. H. pylori express multiple virulence factors for survival in the hostile acid gastric environment. The expression of oncogenic protein cytotoxin-associated gene A (CagA), vacuolating cytotoxin A (VacA), and outer inflammatory protein is essential for H. pylori to exert pathogenesis towards the host. Interestingly, <3% of H. pylori-infected subjects develop gastric cancer, suggesting a unique way of interaction between the host's immune response and H. pylori virulence factors. This article is aimed to review the epidemiology and role of H. pylori in gastric carcinogenesis. A better understanding of the interaction between H. pylori virulence factors and host is required for better gastric cancer prevention.

Review of current diagnostic methods and advances in Helicobacter pylori diagnostics in the era of next generation sequencing

Helicobacter pylori (H. pylori) infection is highly prevalent in the human population and may lead to severe gastrointestinal pathology including gastric and duodenal ulcers, mucosa associated tissue lymphoma and gastric adenocarcinoma. In recent years, an alarming increase in antimicrobial resistance and subsequently failing empiric H. pylori eradication therapies have been noted worldwide, also in many European countries. Therefore, rapid and accurate determination of H. pylori’s antibiotic susceptibility prior to the administration of eradication regimens becomes ever more important. Traditionally, detection of H. pylori and its antimicrobial resistance is done by culture and phenotypic drug susceptibility testing that are cumbersome with a long turn-around-time. Recent advances in diagnostics provide new tools, like real-time polymerase chain reaction (PCR) and line probe assays, to diagnose H. pylori infection and antimicrobial resistance to certain antibiotics, directly from clinical specimens. Moreover, high-throughput whole genome sequencing technologies allow the rapid analysis of the pathogen’s genome, thereby allowing identification of resistance mutations and associated antibiotic resistance. In the first part of this review, we will give an overview on currently available diagnostic methods for detection of H. pylori and its drug resistance and their implementation in H. pylori management. The second part of the review focusses on the use of next generation sequencing technology in H. pylori research. To this end, we conducted a literature search for original research articles in English using the terms “Helicobacter”, “transcriptomic”, “transcriptome”, “next generation sequencing” and “whole genome sequencing”. This review is aimed to bridge the gap between current diagnostic practice (histology, rapid urease test, H. pylori culture, PCR and line probe assays) and new sequencing technologies and their potential implementation in diagnostic laboratory settings in order to complement the currently recommended H. pylori management guidelines and subsequently improve public health.

A population-based retrospective study comparing cancer mortality between Moluccan migrants and the general Dutch population: equal risk 65 years after immigration?

OBJECTIVE

To test the hypothesis that cancer mortality rates among the Moluccan-Dutch, the oldest non-Western migrant group to arrive in the Netherlands after the Second World War, are similar to those in the general Dutch population.

DESIGN

Population-based retrospective study.

SETTING

Data from the national cause of death registry in the Netherlands and municipal registries.

PARTICIPANTS

Using historic records containing family names of all Moluccan-Dutch who arrived in the Netherlands in 1951, we identified 81 591 Moluccan-Dutch persons in the national cause of death registry of the Netherlands. The reference group consisted of 15 866 538 persons of the general Dutch population.

OUTCOME MEASURES

Mortality data were linked to demographic data from municipal registries. We calculated all-cancer and cancer-specific mortality and measured differences between the two groups using Poisson regression, adjusting for sex, age and area socioeconomic status. We conducted a sub-analysis for the first-generation and second-generation Moluccan-Dutch.

RESULTS

There was no difference in all-cancer mortality between Moluccan-Dutch and the general Dutch population. Mortality was higher among Moluccan-Dutch for liver, cervix and corpus uteri cancers, but lower for stomach, oesophagus, kidney and nervous system cancers. For most cancers, mortality risk as compared with the general Dutch population varied between different generations of Moluccan-Dutch.

CONCLUSIONS

Several decades after migration, the Moluccan-Dutch show similar all-cancer mortality, but different cancer-specific mortality rates, when compared with the general Dutch population.

Prevalence and genotyping of Helicobacter pylori in endoscopic biopsy samples from a Chinese population

Background:

Helicobacter pylori inhabit the gastric mucosa of humans and are associated with several gastrointestinal diseases which include gastric cancer, peptic ulcer, chronic gastritis and gastric mucosa-associated lymphoid tissue lymphoma. Helicobacter pylori exhibit a high degree of genetic variability and are associated with its epidemiological, pathological characteristics and dynamics of transmission. The objective of the study was to determine the prevalence and genetic heterogeneity of H. pylori isolated from endoscopic biopsy samples from a Chinese population.

Methods:

Gastric biopsy samples from 86 patients (males, 55; females, 35) who presented to the endoscopic section for various gastrointestinal abnormalities were collected. The samples were subjected to a real-time polymerase chain reaction (PCR) and microbial culture for the isolation of H. pylori. Further, the isolates were subjected to randomly amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) analysis.

Results:

Of the 86 gastric biopsy samples, 61 (70.9%) samples were positive for rapid urease test and 37 (43%) samples (28 from male and nine from female) grew H. pylori. Among the biopsy samples subjected to real-time PCR, 39 (45.3%) samples were found to be positive for H. pylori. The RAPD analysis yielded 15 different patterns (four to 17 different sized fragments per strain). The phylogenetic analysis of RAPD yielded 22 clusters at a similarity level ranging from 63% to 100%. RFLP analysis yielded nine different patterns (two to six different sized fragments per strain). Two major restriction patterns were identified, of which 14 (37.8%) strains forms the most common pattern (genotype I) followed by five (13.5%, genotype II) strains with an intra-strain similarity of 100%.

Conclusions:

The overall prevalence of H. pylori was 45.3%. Despite reports on the declining trend in the prevalence of H. pylori infections, our prevalence rate was still higher than those reported from other developed countries. However, further studies involving a large sample size and covering more regions of China is highly warranted.

Tree nut, peanut, and peanut butter consumption and the risk of gastric and esophageal cancer subtypes: the Netherlands Cohort Study

BACKGROUND

Nut consumption has been associated with reduced cancer-related mortality. However, it is unclear whether nut consumption also reduces the risk of esophageal and gastric cancer subtypes. We prospectively investigated the relationship of tree nut, peanut, and peanut butter intake with risk of esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAC), gastric cardia adenocarcinoma (GCA), and gastric non-cardia adenocarcinoma (GNCA) in the Netherlands Cohort Study.

METHODS

In 1986, 120,852 males and females, aged 55-69 years, completed a baseline questionnaire on diet and cancer risk factors. After 20.3 years of follow-up, 133 ESCC, 200 EAC, 191 GCA, and 586 GNCA cases, and 3,720 subcohort members were available for multivariable Cox regression analyses, using a case-cohort approach.

RESULTS

Increased total nut consumption was significantly associated with a decreased risk of ESCC and GNCA [HRs (95% CIs) for 10 + g/day vs. nonconsumers = 0.54 (0.30-0.96) and 0.73 (0.55-0.97), respectively], but not with EAC and GCA risk. Similar trends were observed for tree nut and peanut intake, which were mostly nonsignificant. For peanut butter intake, no significant associations were found. When excluding the first four years of follow-up to reduce the possible influence of reversed causation, the relation between nut consumption and ESCC risk attenuated, but remained inverse.

CONCLUSIONS

Our findings suggest that increased tree nut and peanut consumption is inversely associated with GNCA risk and possibly with ESCC risk, but not with the risk of the other esophageal and gastric cancer subtypes.

Risk of Oral and Upper Gastrointestinal Cancers in Persons With Positive Results From a Fecal Immunochemical Test in a Colorectal Cancer Screening Program

BACKGROUND & AIMS

European guidelines recommend screening for colorectal cancer (CRC) using the fecal immunochemical test (FIT), with follow-up colonoscopies for individuals with positive test results. However, more than half of participants with positive results from the FIT are not found to have advanced neoplasia in the colonoscopy examination. Fecal occult blood might also come from the upper gastrointestinal (GI) tract, so perhaps we should consider esophagogastroduodenoscopy (EGD), to detect upper GI cancers. We aimed to determine how many individuals are found to have oral or upper GI cancers (oral cavity, throat, esophageal, gastric, or small bowel cancer) within 3 years after a positive or negative result from a FIT in a CRC screening program.

METHODS

We performed a retrospective analysis of data from a pilot study of 3 rounds of biennial FIT-based screening for CRC in 2 regions in the west of the Netherlands, from 2006 through October 2012. Participants who developed oral or upper GI cancers were identified through linkage with the National Cancer Registry. We classified these cancers into 3 groups: those that developed in individuals with a positive result from a FIT but negative findings from colonoscopy (no advanced neoplasia), those that developed in individuals with a positive result from a FIT and a positive finding from colonoscopy (advanced neoplasia), and those that developed in individuals with negative results from a FIT. We compared oral and upper GI cancer incidence among groups.

RESULTS

Among 16,165 screening participants, linkage identified 52 persons who developed an oral or upper GI cancer within 3 years after a FIT. We found no significant difference in incidence values between individuals with a positive vs a negative FIT result: 8 cancers developed in individuals with a positive result from a FIT (0.37%; 95% CI, 0.19-0.76) and 44 developed in individuals with a negative result from a FIT (0.31%; 95% CI, 0.23-0.42) (P = .65). Of the 8 individuals with a positive result from a FIT and an oral or upper GI cancer, 6 were diagnosed after negative findings from colonoscopy and 2 after positive findings from colonoscopy. We found that only 0.14% of all persons with a positive result from a FIT were diagnosed with a gastric or esophageal cancer within 3 years.

CONCLUSION

In a study of individuals in the Netherlands undergoing screening for CRC by FIT, we found fewer than 1% of patients with a positive result from the FIT to receive a diagnosis of upper GI cancers within 3 years. Routine EGD investigation of individuals with positive results from a FIT and negative findings from colonoscopy is therefore not recommended. TrialRegister.nl, Number: NTR5385.

Prevalence of Helicobacter pylori among Alaskans: Factors associated with infection and comparison of urea breath test and anti-Helicobacter pylori IgG antibodies

BACKGROUND

Helicobacter pylori is one of the most common human infections in the world, and studies in Alaska Native people, as well as other Indigenous peoples, have shown a high prevalence of this gastric infection. This study was undertaken to determine the prevalence of H. pylori infection by urea breath test (UBT) and anti- H. pylori IgG among Alaskans living in four regions of the state and to identify factors associated with infection.

METHODS

A convenience sample of persons > 6 months old living in five rural and one urban Alaskan community were recruited from 1996 to 1997. Participants were asked about factors possibly associated with infection. Sera were collected and tested for anti- H. pylori IgG antibodies; a UBT was administered to participants > 5 years old.

RESULTS

We recruited 710 people of whom 571 (80%) were Alaska Native and 467 (66%) were from rural communities. Rural residents were more likely to be Alaska Native compared with urban residents (P < .001). Of the 710 people, 699 (98%) had a serum sample analyzed, and 634 (97%) persons > 5 years old had a UBT performed. H. pylori prevalence was 69% by UBT and 68% by anti- H. pylori IgG. Among those with a result for both tests, there was 94% concordance. Factors associated with H. pylori positivity were Alaska Native racial status, age ≥ 20 years, rural region of residence, living in a crowded home, and drinking water that was not piped or delivered.

CONCLUSIONS

Helicobacter pylori prevalence is high in Alaska, especially in Alaska Native persons and rural residents. Concordance between UBT and serology was also high in this group. Two socioeconomic factors, crowding and drinking water that was not piped or delivered, were found to be associated with H. pylori positivity.

The epidemiology of Helicobacter pylori infection in Europe and the impact of lifestyle on its natural evolution toward stomach cancer after infection: A systematic review

BACKGROUND

Helicobacter pylori is a recognized cause of stomach cancer, but only a fraction of infected subjects develop cancer. This systematic review 1, summarizes the prevalence of infection with this bacterium in Europe; and 2, reviews the possible impact of particular lifestyles in progression from infection to stomach cancer.

MATERIALS AND METHODS

A systematic literature search was conducted in two databases by two independent investigators. Studies describing prevalence of infection among European healthy adult populations and worldwide studies analyzing the impact of lifestyle factors in association with H. pylori on stomach cancer risk were included.

RESULTS

Variable H. pylori infection prevalence was observed depending on region and study period. The lowest infection prevalences were found in Northern Europe, while the highest were in Eastern and Southern Europe, up to 84% in Portugal and Poland. Studies on smoking, salt, and meat consumption demonstrated increased risks of developing stomach cancer among H. pylori-infected individuals, while studies relating the intake of fruit, vegetables, and vitamins demonstrated decreased risks, but the levels of significance differed importantly between studies. No significant interaction could be found for alcohol consumption or physical activity.

CONCLUSIONS

Recent data showed remaining high H. pylori infection rates in several European regions. This systematic review suggests that a number of correctable lifestyle factors could impact the disease progression toward H. pylori-associated stomach cancer. However, additional research is required to determine the potential role of targeted interventions in reducing stomach cancer development after H. pylori infection.

Seroprevalence of Helicobacter pylori in Hispanics living in Puerto Rico: A population-based study

BACKGROUND

Helicobacter pylori is an important etiologic factor for peptic ulcers and gastric cancer, one of the top ten leading causes of cancer death in Puerto Rico. However, the prevalence of H. pylori infections in this population was previously unknown. The aim of this study was to examine the seroprevalence of H. pylori and its associated risk factors in Puerto Rico.

MATERIALS AND METHODS

A cross-sectional study was designed using an existing population-based biorepository. Seropositivity was determined using the Premier^™ H. pylori immunoassay. Helicobacter pylori seroprevalence was estimated with 95% confidence using marginal standardization following logistic regression. To assess the risk factors associated with H. pylori seropositivity, a multivariable log-binomial model was fitted to estimate the prevalence ratio (PR) and its 95% confidence interval (95% CI).

RESULTS

A total of 528 population-based serum samples were analyzed. The mean age of the study population was 41 ± 12 years, of whom 55.3% were females. The overall seroprevalence of H. pylori was 33.0% (95% CI = 28.3%-38.1%). Increasing age and having <12 years of education were significantly (P < .05) associated with H. pylori seropositivity in the multivariable model; however, residing in counties with low population density reached marginal significance (P = .085).

CONCLUSIONS

We report that H. pylori infection is common among Hispanics living in Puerto Rico. The H. pylori seroprevalence observed in Puerto Rico is similar to the seroprevalence reported in the overall population of the United States. The association between H. pylori seroprevalence and the risk factors analyzed offers insight into the epidemiology of gastric cancer in Puerto Rico and warrants further investigation.

Helicobacter pylori-induced gastric pathology: insights from in vivo and ex vivo models

Gastric colonization with Helicobacter pylori induces diverse human pathological conditions, including superficial gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric adenocarcinoma and its precursors. The treatment of these conditions often relies on the eradication of H. pylori, an intervention that is increasingly difficult to achieve and that does not prevent disease progression in some contexts. There is, therefore, a pressing need to develop new experimental models of H. pylori-associated gastric pathology to support novel drug development in this field. Here, we review the current status of in vivo and ex vivo models of gastric H. pylori colonization, and of Helicobacter-induced gastric pathology, focusing on models of gastric pathology induced by H. pylori, Helicobacter felis and Helicobacter suis in rodents and large animals. We also discuss the more recent development of gastric organoid cultures from murine and human gastric tissue, as well as from human pluripotent stem cells, and the outcomes of H. pylori infection in these systems.

Current prevalence of Helicobacter pylori infection in patients with dyspepsia treated in Warsaw, Poland

INTRODUCTION

The prevalence of Helicobacter pylori (Hp) infection in patients with dyspepsia has important clinical and epidemiological implications. However, the current prevalence of Hp infection among patients within Poland is unknown; the last data were collected a decade ago and the majority of previous studies showed the prevalence to be between 60% and 100%.

AIM

To establish the current prevalence of Hp infection among patients with dyspepsia in Warsaw, Poland.

MATERIAL AND METHODS

The study group comprised 148 patients (126 women and 22 men) with dyspepsia, treated in two outpatient clinics in Warsaw. The mean age in the group that tested positive for Hp was 45.8 years (SD = 14.86; median = 51; min = 19; max = 64). They were tested for Hp infection with a urea breath test that uses 13C-enriched urea and isotope ratio mass spectrometry.

RESULTS

Helicobacter pylori infection was found in 53 patients (44 women and 9 men), i.e. in 35.8% of the whole study group. We did not find any significant relationship between Hp infection and the patients' age, gender, or their body mass index.

CONCLUSIONS

The current prevalence of Hp infection among patients with dyspepsia treated in Warsaw is 35.8%. However, our data suggest almost a two-fold fall in the prevalence of Hp infection compared to the previous Polish studies.

Population screening and treatment of Helicobacter pylori infection

Helicobacter pylori is an important human pathogen, associated with a substantial burden from both malignant and non-malignant diseases. The bacterium is classed as a human carcinogen, being strongly linked with gastric cancer, the third most common cause of cancer death worldwide and is also associated with common conditions such as dyspepsia and peptic ulcer. Eradication of H. pylori reduces the incidence of gastric cancer and peptic ulcer, as well as the prevalence and costs of managing dyspepsia. Economic analyses suggest that eradication of H. pylori as a means of controlling gastric cancer is cost-effective in high-risk populations. Even in populations at low risk of gastric cancer, there might be other benefits arising from screening and treatment, owing to the effects on non-malignant upper gastrointestinal diseases. However, public health authorities have been slow to consider the benefits of population-based screening and treatment as a means of reducing the morbidity and mortality associated with the infection. There are also concerns about widespread use of eradication therapy, including antimicrobial resistance and a rise in the prevalence of diseases that are negatively associated with H. pylori, such as GERD, Barrett oesophagus, asthma and obesity. This Review summarizes these issues.

Association between genetic variants in the XPG gene and gastric cancer risk in a Southern Chinese population

Xeroderma pigmentosum group G (XPG) recognizes and excises DNA damage on the 3' side during the DNA repair process. Previous studies indicated that XPG gene polymorphisms may associate with gastric cancer susceptibility, but results were inconsistent. We evaluated the association of five potentially functional XPG polymorphisms (rs2094258 C>T, rs751402 C>T, rs2296147 T>C, rs1047768 T>C, and rs873601 G>A) with gastric cancer susceptibility in 1142 gastric cancer cases and 1173 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression models. Overall, no significant association was detected between any of selected polymorphism and gastric cancer risk. However, we found that individuals carrying 3-4 risk genotypes were at significantly higher risk of gastric cancer than those with 0-2 risk genotypes (OR=1.32, 95% CI=1.04-1.68, P=0.021). The stratification analysis revealed that the cumulative effect of risk genotypes (3-4 vs. 0-2) on gastric cancer were more prominent among subgroups older than 58 years and men. In conclusion, our results indicated that none of the selected XPG polymorphism could significantly alter gastric cancer susceptibility alone. These polymorphisms might collectively confer increased gastric cancer susceptibility. These findings would be strengthened by larger prospective multicenter studies involving different ethnic populations.

The All-Age Prevalence of Helicobacter pylori Infection and Potential Transmission Routes. A Population-Based Study

BACKGROUND AND AIMS

Previous research on H. pylori epidemiology has mostly focused on adult populations. We have aimed to study H. pylori prevalence in all age groups including children and adolescents and to identify potential routes of transmission.

METHODS

Subjects from all age groups (children 0-11 years, adolescents 12-17 years and adults ≥18 years of age), recruited from both an urban and a rural community in Northern Norway, were invited to provide stool samples for the diagnosis of H. pylori antigen and to fill in a questionnaire (adult and adolescents only) on gastrointestinal symptoms, lifestyle factors and biometric data.

RESULTS

A total of 1 624 (35.3%) of the invited subjects, including 173 (39.3%) of the children, 46 (19.2%) of the adolescents, and 1 416 (36.1%) of the adults, responded to the invitation. H. pylori infection was nearly undetectable (0.6%) among the children, whereas the prevalence increased from 20% in adolescents toward a peak of 45% in the highest age group. Univariate analyses of possible risk factors of H. pylori infection showed significant associations to private well water, the use of outhouse toilet, and having farm animals in childhood, but the associations waned in multivariate analyses.

CONCLUSIONS

In our populations, with apparent high hygienic standards, the transmission of H. pylori infection may start not only in childhood, but also in adolescence, where potential transmission routes may be outdoor toilet use, private well water, and farm animals.

Does long-term profound inhibition of gastric acid secretion increase the risk of ECL cell-derived tumors in man?

OBJECTIVE

Since the description of ECL cell-derived tumors in rodents after long-term profound acid inhibition inducing hypergastrinemia, there has been concern that proton pump inhibitors (PPIs) could also do that in man. The recent description of a Spanish family with gastric ECL cell tumors at the age of about 30 years secondary to a defect in the proton pump due to mutation in the ATP4A gene clearly shows that hypergastrinemia alone also is sufficient to induce ECL cell neoplasia in man. The present review aims to evaluate the risk of gastric neoplasia secondary to gastric acid inhibition.

METHODS

Literature (MEDLINE) was searched for the role of the ECL cell in gastric carcinogenesis in animals and man in general and particularly secondary to long-term inhibition of acid secretion.

RESULTS

An important proportion of patients treated with PPI develops hypergastrinemia causing ECL cell hyperplasia and the first descriptions of ECL cell carcinoids secondary to PPI have been reported. The role of the ECL cell has hitherto been under estimated in gastric carcinogenesis in man where for instance the signet ring cell type of gastric carcinoma seems to originate from the ECL cell.

CONCLUSIONS

The first two of three steps in rodent ECL cell carcinogenesis (hyperplasia, carcinoid, and carcinoma) secondary to PPI dosing, have been described for man. It is every reason to believe that the final step, gastric carcinoma, will develop also in man. Clinical decisions should be based not only on so-called evidence based medicine, but also on physiological knowledge and animal studies.

Helicobacter pylori Infection Rates in Patients Undergoing Endoscopy in the Interior of Borneo

INTRODUCTION

Very limited data are available on the Helicobacter pylori infection among the population of interior Borneo. We aimed to investigate the H. pylori infection rate among an endoscoped interior Borneo population and to report the differences between the infected and noninfected patients.

METHODS

We retrospectively analyzed the data of the rapid urease test (RUT) records in Endoscopy Unit Hospital Keningau from January 2009 to May 2014. Student's t-test, chi-square test or Fisher's exact test were used accordingly. Multiple logistic regression analysis was used to identify independent risk factors for H. pylori infection. Birth cohort was analyzed against H. pylori infection rate with chi-square test.

RESULTS

Overall, there were 215 of 774 (27.8%) positive RUTs. Patients with H. pylori infection were younger (47.66 ± 14.93 vs 50.50 ± 15.02 years, p = .019), more likely to be female (OR = 1.54, 95% CI 1.12-2.13, p = .008) and originated from the Pensiangan district (OR = 1.63, 95% CI 1.01-2.64, p = .047). Chinese patients were less likely infected with H. pylori (OR = 0.36, 95% CI 0.16-0.80, p = .013). Birth cohort was significantly associated with H. pylori infection rate (χ(2) (7) = 14.71, p = .040) with an increasing trend of H. pylori infection rate in patients born later (χ(2) (1) = 5.26, p = .022).

CONCLUSION

The overall H. pylori infection rate in this population was unexpectedly low. Accordingly, it may be a recent arrival in this community. Gender, age, dietary practice, socioeconomic status, and ethnicity were among the factors associated with H. pylori infection.

Pathological and Clinical Correlation between Celiac Disease and Helicobacter Pylori Infection; a Review of Controversial Reports

There are overwhelming reports and descriptions about celiac associated disorders. Although there is a clear genetic association between celiac disease (CD) and some gastrointestinal disorders, there are controversial reports claiming an association between CD and Helicobacter pylori (H. pylori) infection. Different studies indicated the possible association between lymphocytic gastritis and both CD and H. pylori infection, although this evidence is not consistently accepted. Also it was shown that an increase in intraepithelial lymphocytes count is associated with both H. pylori infection and celiac disease. Therefore the following questions may raise: how far is this infection actually related to CD?, which are the underlying patho-mechanisms for these associations? what are the clinical implications? what is the management? and what would be the role of gluten free diet in treating these conditions? PubMed (PubMed Central), Ovid, ISI of web knowledge, and Google scholar were searched for full text articles published between 1985 and 2015. The associated keywords were used, and papers described particularly the impact of pathological and clinical correlation between CD and H. pylori infection were identified. In this review we tried to answer the above questions and discussed some of the recent developments in the pathological and clinical aspects of CD and H. pylori infection.

Equivalent Helicobacter pylori infection rates in Lynch syndrome mutation carriers with and without a first-degree relative with gastric cancer

BACKGROUND

Patients with Lynch syndrome (LS) are at an increased risk of developing gastric cancer. In 2010, a guideline that recommended to screen all patients for Helicobacter pylori was implemented in the Netherlands. H. pylori is an important risk factor in the development of gastric cancer in the general population, and eradication of the bacterium reduces this risk. We aimed to assess the proportion of LS patients being tested and the yield and also addressed the question whether H. pylori infection is more prevalent in LS families with known cases of gastric cancer.

METHODS

Proven mutation carriers from five different Dutch hospitals were included. The implementation of H. pylori screening and its outcome was examined. The observation period was 2008-2013. The presence of first-degree family members with gastric cancer was noted, and it was observed if H. pylori infection was more prevalent in Lynch families with known cases of gastric cancer. Obtainable endoscopy reports were reviewed.

RESULTS

Four hundred forty-three (male, 184) proven mutation carriers were included. The proportion of patients screened increased after 2010, from 37 to 68%. Twenty percent of the patients were infected. The 25 patients who had a first-degree family member with gastric cancer did not have a higher infection rate. In 30% of cases, an endoscopy was performed; in four patients, intestinal metaplasia and in eight patients, gastric cancer was found.

CONCLUSION

The recommendation to screen for H. pylori is increasingly followed. The prevalence of infection in this patient group does not differ from the general population. Patients who had a first-degree family member with gastric cancer did not have a higher infection rate.

Prevalence of Helicobacter pylori infection among preschool children in Latvia: no significant decrease in prevalence during a ten year period

Aims: Published data show a trend of decreasing prevalence of Helicobacter pylori in Eastern European countries due to socioeconomic changes. The aim of this study was to determine the prevalence of H. pylori infection among children in Latvia and to compare these results with previous studies in the same population. The risk factors associated with infection were also analysed. Methods: Preschool children in kindergartens and primary health care centres were investigated using a stool antigen test. Their parents were asked to fill out a questionnaire about possible risk factors. Statistical analysis included Pearson’s χ2 test and linear regression analysis. Results: The prevalence of H. pylori infection determined by the monoclonal stool antigen test in children aged 1–6 years (median 5 years) was 15.5% (15/101) (95% confidence interval 8.67–23.48%). In the regression analysis, H. pylori positivity was significantly negatively associated with the consumption of imported fruit at least once per week ( p=0.02). Conclusions: The prevalence of H. pylori in the studied population has not decreased significantly during the last decade and is still associated with socioeconomic factors. The role of some dietary factors (e.g. the consumption of fruit) in the spread of infection should be studied further.

Review article: the prevalence of Helicobacter pylori and the incidence of gastric cancer across Europe

BACKGROUND

There is little up-to-date review evidence on the prevalence of Helicobacter pylori across Europe.

AIM

To establish regional and national patterns in H. pylori prevalence across Europe. Secondly, to establish trends over time in H. pylori prevalence and gastric cancer incidence and, thirdly, to report on the relationship between H. pylori prevalence and age group across Europe.

METHODS

A review of H. pylori prevalence from unselected surveys of adult or general populations across 35 European countries and four European regions since 1990. Secondly, an analysis of trends over time in H. pylori prevalence and in gastric cancer incidence from cancer registry data.

RESULTS

Helicobacter pylori prevalence was lower in northern and western Europe than in eastern and southern Europe (P < 0.001). In 11 of 12 European studies that reported on trends, there were sharp reductions in H. pylori prevalence (mean annual reduction = 3.1%). The mean annual reduction in the incidence of gastric cancer across Europe from 1993 to 2007 was 2.1% with little variation regionally across Europe (north 2.2%, west 2.3%, east 1.9% and south 2.0%). Sharp increases in age-related prevalence of H. pylori often levelled off for middle age groups of about 50 years onwards, especially in areas with high prevalence.

CONCLUSIONS

This review shows that H. pylori prevalence is much higher in less affluent regions of Europe and that age-related increases in prevalence are confined to younger age groups in some areas. There were sharp reductions in both H. pylori prevalence and gastric cancer incidence throughout Europe.

Correlation of nodular gastritis with Helicobacter pylori infection

Nodular gastritis (NG) is a form of chronic Helicobacter pylori (H. pylori) associated gastritis affecting the gastric antrum, which is characterized endoscopically by the presence of small nodular lesions resembling gooseflesh. It is generally accepted that NG is characterized histologically by hyperplasia of lymphoid follicles. At present, there is a wide range of H. pylori infections in the world, and NG is an endoscopic sign of H. pylori infection. After H. pylori eradication therapy, the clinical manifestations, pathology and endoscopic performance of NG patients can be improved significantly. Therefore, H. pylori eradication should be performed as early as possible in NG patients. The research data about NG is still very limited. The relationship between NG as potentially precancerous lesions and gastroduodenal diseases is still a debate and needs to be further explored. Here we review the research progress in understanding the correlation between NG and H. pylori.

Intergenerational reduction in Helicobacter pylori prevalence is similar between different ethnic groups living in a Western city

OBJECTIVE

Helicobacter pylori colonisation rates in childhood have declined in Western populations, but it is unknown whether this trend is similar in children of non-Western ethnic backgrounds, born in a Western country. We aimed to identify H. pylori status in children, and determine mother-to-child transmission and risk factors for colonisation.

DESIGN

Antibodies against H. pylori and cytotoxin-associated gene A (CagA) were measured in children participating in a population-based prospective cohort study in Rotterdam, the Netherlands. Information on demographics and characteristics was collected using questionnaires.

RESULTS

We analysed the serum of 4467 children (mean age 6.2 years±0.4 SD) and compared the results with the H. pylori status of their mothers (available for 3185 children). Overall, 438 (10%) children were H. pylori-positive, of whom 142 (32%) were CagA-positive. Independent risk factors for colonisation were: maternal H. pylori positivity (OR 2.12; 95% CI 1.62 to 2.77), non-Dutch ethnicity (OR 2.05; 95% CI 1.54 to 2.73), female gender (OR 1.47; 95% CI 1.20 to 1.80) and lower maternal education level (OR 1.38; 95% CI 1.06 to 1.79). Comparing mothers and children, we found an intergenerational decrease of 76% and 77% for Hp(+)CagA(-) and Hp(+)CagA(+)-strains, respectively, consistent across all nine ethnic groups studied. Male gender, higher maternal educational level and no older siblings, were independently associated with absence of H. pylori.

CONCLUSIONS

Although the highest H. pylori and CagA prevalence was found in children of non-Dutch ethnicities, the decreased colonisation rates were uniform across all ethnic groups, implying the importance of environmental factors in H. pylori transmission in modern cities, independent of ethnicity.

Acid suppression and surgical therapy for Barrett's oesophagus

Gastro-oesophageal reflux disease is a common medical problem in developed countries, and is a risk factor for the development of Barrett's oesophagus and oesophageal adenocarcinoma. Both proton pump inhibitor therapy and antireflux surgery are effective at controlling endoscopic signs and symptoms of gastro-oesophageal reflux in patients with Barrett's oesophagus, but often fail to eliminate pathological oesophageal acid exposure. The current available studies strongly suggest that acid suppressive therapy, both pharmacological as well as surgical acid suppression, can reduce the risk the development and progression in patients with Barrett's oesophagus, but are not capable of complete prevention. No significant differences have been found between pharmacological and surgical therapy. For clinical practice, patients should be prescribed a proton pump inhibitor once daily as maintenance therapy, with the dose guided by symptoms. Antireflux surgery can be a good alternative to proton pump inhibitor therapy, but should be primarily offered to patients with symptomatic reflux, and not to asymptomatic patients with the rationale to protect against cancer.

Epidemiology of Helicobacter pylori infection

Medline and PubMed databases were searched on epidemiology of Helicobacter pylori for the period of April 2013-March 2014. Several studies have shown that the prevalence of H. pylori is still high in most countries. In north European and North American populations, about one-third of adults are still infected, whereas in south and east Europe, South America, and Asia, the prevalence of H. pylori is often higher than 50%. H. pylori remains highly prevalent in immigrants coming from countries with high prevalence of H. pylori. However, the lower prevalence of infection in the younger generations suggests a further decline of H. pylori prevalence in the coming decades. Low socioeconomic conditions in childhood are confirmed to be the most important risk factors for H. pylori infection. Although the way the infection is transmitted is still unclear, interpersonal transmission appears to be the main route. Finally, H. pylori recurrence after successful eradication can still occur, but seems to be an infrequent event.

Helicobacter pylori and public health

Gastric cancer and peptic ulcer between them cause the death of over a million people each year. A number of articles this year have studied changes in the prevalence of the infection in a variety of countries and ethnic groups. They confirm the known risk factors for infection, principally a low standard of living, poor education, and reduced life span. The prevalence of infection in developed countries is falling, but more slowly now than was the case before, meaning that a substantial number of the population will remain infected in the years to come. Reinfection is more common in less developed countries. The incidence of gastric cancer is highest in populations with a high prevalence of infection. Population test and treat is a cost-effective means of preventing gastric cancer. Peptic ulcer is the commonest cause of death in patients undergoing emergency surgery. The alleged risk that treatment may cause some to develop reflux esophagitis remains controversial.

Review article: the epidemiology and prevention of gastric cancer

BACKGROUND

Gastric cancer can be divided into cardia and noncardia gastric adenocarcinoma (NCGA). Non cardia gastric cancer is a disease that has declined in global incidence but has remained as an extremely lethal cancer.

AIM

To review recent advances in epidemiology and strategies in prevention of non cardia gastric cancer.

METHODS

A rapid literature search strategy was developed for all English language literature published before March 2013. The search was conducted using the electronic databases PubMed and EMBASE. The search strategy included the keywords 'stomach neoplasms', 'gastric cancer', 'epidemiology', 'risk factor', 'early detection of cancer', 'mass screening', 'cancer burden', 'prevention' and 'cost-effectiveness'. The search strategy was adjusted according to different requirements for each database. The specific search was also performed in cancer-related websites for country-specific information. The search was limited to past 10 years.

RESULTS

Gastric cancer is the fifth most common cancer but the third leading cause of cancer death. The case fatality rate is 75%. Screening by radiological or endoscopic methods has limited success in prevention of gastric cancer. Helicobacter pylori has been identified as a carcinogen, accounting for 60-70% of gastric cancer globally and eradication is a potential preventive measure. A meta-analysis in 2009 demonstrated that individuals treated with H. pylori eradication therapy can reduce gastric cancer risk. The extended Shandong Intervention trial that lasted 14.3 years showed that H. pylori eradication therapy significantly reduced gastric cancer incidence by 39%. Consensus groups from Asia, Europe and Japan have recommended H. pylori eradication as primary prevention in high-risk areas. Following eradication therapy, endoscopic surveillance of pre-malignant lesions using enhanced imaging appears to be another promising preventive strategy.

CONCLUSIONS

Gastric cancer remains a major diagnostic and therapeutic challenge. There is emerging evidence that H. pylori eradication in high gastric cancer regions can lead to a decline in the incidence of this highly lethal disease.