Helicobacter pylori infection in an Australian regional city: prevalence and risk factors

Epidemiology of Helicobacter pylori in Australia: a scoping review

Background

Helicobacter pylori (H. pylori), a bacterium implicated in the development of peptic ulcer and gastric cancer, is estimated to infect around half the world's population. Its prevalence in Australia is unclear. This scoping review aimed to evaluate all Australian literature providing estimates of the prevalence of H. pylori.

Methods

Australian studies examining H. pylori prevalence from 1982 onwards were eligible for inclusion. Medline, Embase and Scopus databases, and grey literature sources, were searched. Two independent reviewers undertook a two-stage screening process. Data were extracted by two independent reviewers using a pre-specified template.

Results

Of 444 identified studies, 75 were included in the review. H. pylori prevalence in Australian population-based studies (n = 8) ranged from 38.0% in 1991 to 15.1% in 2002; however, estimated prevalence across all non-clinical population studies in diverse sub-groups (n = 29) has varied dramatically. Decreased prevalence has been more marked in populations with gastrointestinal symptoms and conditions compared to non-clinical populations. Data on H. pyloriprevalence in vulnerable populations are lacking.

Conclusions

This is the first scoping review of Australian studies reporting H. pylori prevalence. A wide range of study designs, population groups, geographic regions, and diagnostic methods was included, involving data collected over a 50-year period (1969 to 2018). The summary of H. pylori prevalence estimates over time in this review points to a decrease in prevalence in Australia, particularly among populations with gastrointestinal symptoms and illnesses; however, it is unknown whether there is inequity in prevalence trends across vulnerable sub-groups of the Australian population. Future research and interventions supporting the health and wellbeing of vulnerable populations is required to ensure equitable health gains are made for all.

Higher Risk of Gastric Helicobacter pylori Infection in Patients with Periodontitis: A Nationwide Population-Based Retrospective Cohort Study in Taiwan

Periodontitis is the most prevalent chronic inflammatory oral disease that is characterized by tooth loss and is commonly associated with several systemic inflammatory diseases. Some epidemiological studies suggest that those suffering from periodontitis might be at a greater risk of developing gastric Helicobacter pylori (Hp) infection; however, evidence that showing the association between periodontitis and the risk of gastric Hp infection is less clear. We conducted a large-scale, population-based study in Taiwan with a 13-year follow-up period to evaluate the risk of gastric Hp in a periodontitis patient cohort. To conduct this study, we used epidemiological data from the Taiwanese Longitudinal National Health Insurance Research Database (NHIRD) from 2000 to 2013. We selected 134,474 participants (64,868 males and 69,606 females with a minimum age of 20 years), with and without periodontitis, and matched patient cohort groups for age, sex, index year, and co-morbidities. The Cox proportional hazards regression model was used to examine the risk of gastric Hp infection in patients with periodontitis. Patients with periodontitis exhibited a higher risk of developing gastric Hp infection compared to those individuals/groups without periodontitis (1.35 vs. 0.87 per 1000 person-years, adjusted the hazards ratio (aHR 1.52), and 95% confidence intervals (CIs) 1.38–1.67, p < 0.001). The risk of gastric Hp infection persisted even after stratifying by age (aHR = 1.96 (1.79–2.13) for 50–64 years and 1.70 (1.49–1.94) for ≥65 years), gender (aHR = 1.20 (1.11–1.29) for men), and presence of comorbidities of hypertension (aHR = 1.24 (1.11–1.38)), hyperlipidemia (aHR = 1.28 (1.14–1.42)), COPD (aHR = 1.45 (1.31–1.61)), CLD (aHR = 1.62 (1.47–1.77)) and CKD (aHR = 1.44 (1.04–1.99)). Overall, our findings showed that periodontitis patients have a greater risk for gastric Hp than individuals without periodontitis. Clinicians should perform regular good oral hygiene practices, along with newer treatments, for patients with periodontitis, especially those at higher risk of gastric Hp infection.

Prospective Phase II trial of radiation therapy in localised non-gastric marginal zone lymphoma with prospective evaluation of autoimmunity and Helicobacter pylori status: TROG 05.02/ALLG NHL15

BACKGROUND

This Phase 2 multicentre trial in localised non-gastric marginal zone lymphoma (MZL) evaluated the effectiveness and safety of radiotherapy and documented markers of autoimmunity and Helicobacter pylori infection.

PATIENTS AND METHODS

Eligible patients had Stages I and II or paired-organ, non-gastric MZL. Bone marrow evaluation, autoantibody panel, and H. pylori evaluation were mandatory. Involved-field or involved-site radiotherapy was delivered to 24-30.6 Gy. Detected H. pylori infections underwent eradication.

RESULTS

Between 2006 and 2014, six centres enrolled 70 patients, and 68 commenced treatment. The median age was 59 (range: 23-84) years, and 31 (46%) were male. Overall, 55 patients had Stage I disease, nine patients had Stage II disease, and four patients had paired organ-confined disease. Involved extranodal sites with three or more cases were orbital (n = 18), conjunctiva (n = 13), lacrimal (n = 8), skin (n = 8), salivary (n = 7), and muscle (n = 4). Eight patients had primary nodal MZL. At the median follow-up of 5 years (range 0.7-9.4), progression-free survival and overall survival were 79% and 95%, respectively. One lymphoma-related death and two in-field failures (after 25 and 30 Gy, respectively) occurred. Distant relapse sites were skin (n = 2), lymph nodes (n = 2), duodenum, stomach, muscle, and conjunctiva (1 each). No paired-organ MZL relapsed. Apart from cataracts (n = 18), only three treatment-related late grade ≥3 adverse events occurred. Autoantibodies or autoimmune events were detected in 26 of 68 patients (38%). H. pylori infection was detected in 15 of 63 patients (24%) tested. Neither autoimmunity nor H. pylori was detected in 27 of 68 patients (40%).

CONCLUSIONS

Radiotherapy was a potentially curative treatment with low toxicity in localised non-gastric MZL. Autoimmunity, H. pylori infection or both were detected in 60% of patients.

Antibiotic resistance of Helicobacter pylori in Australia and New Zealand: A systematic review and meta-analysis

OBJECTIVE

While the global prevalence of antibiotic-resistant Helicobacter pylori (H. pylori) is increasing, there is much regional variation, and local data are required to guide eradication therapy. We performed a systematic review and meta-analysis to determine rates of H. pylori antibiotic resistance in Australia and New Zealand.

STUDY DESIGN

Random effects meta-analysis of data from 15 published studies and three published abstracts reporting prevalence of primary or secondary H. pylori antibiotic resistance in Australasia.

DATA SOURCES

PubMed, EMBASE, MEDLINE, PROSPERO, and the Cochrane Library were searched until August, 2020.

DATA SYNTHESIS

Fifteen published studies and three published abstracts were identified; one study was excluded due to high risk of bias. Seventeen studies conducted between 1996 and 2013 were included in the final analysis, 12 reporting primary and five reporting secondary antibiotic resistance. Prevalence of primary resistance was clarithromycin 7.4% (95% confidence interval [CI], 5.3-9.7%), metronidazole 50.0% (95%CI, 23.9-56.1%), fluoroquinolones 3.7% (95%CI, 0.004-14.8%), and both amoxicillin and tetracycline <0.5%. Subgroup analysis (last 20 years) showed doubling of clarithromycin resistance to 16.1% (95%CI 11.2-21.7%) with other resistance stable. Prevalence of secondary resistance was high for all antibiotics, particularly clarithromycin 78.7% (95%CI, 64.1-90.1%) and metronidazole 68.3% (95%CI, 59.9-76.1%).

CONCLUSIONS

The outcomes reveal an increase in primary H. pylori clarithromycin resistance since the year 2000, while metronidazole resistance has remained stable and primary resistance to amoxicillin, tetracycline, and fluoroquinolones is low. Rates of secondary resistance to metronidazole and clarithromycin are high. The results highlight the need for contemporary local data on antibiotic resistance in Australia and New Zealand.

The association between chronic periodontitis and oral Helicobacter pylori: A meta-analysis

BACKGROUND

Epidemiological studies have shown that gastrointestinal Helicobacter pylori (H. pylori) infection is the main cause of chronic gastritis, but the relation between oral H. pylori and chronic periodontitis (CP) remains uncertain. A meta-analysis of published papers was performed to elucidate the correlation between oral H. pylori and CP.

METHOD

To perform this meta-analysis, we searched papers published from 2000 to 2018 on PubMed, OVID, Springer Link, Chinese National Knowledge Infrastructure (CNKI) and Chinese Biology Medicine search engines. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the correlation between H. pylori and CP were estimated. Heterogeneity, publication bias and subgroup analyses were also conducted.

RESULTS

A total of 918 papers on oral H. pylori and CP were collected, and 11 papers were in accordance with the inclusion criteria. Oral H. pylori was suggested to be correlated with CP. The results indicated that a H. pylori-positive state significantly increased the risk of CP 3.42 times (OR = 3.42; 95% CI = 2.71-4.31). A diagnostic test using polymerase chain reaction (PCR) showed a higher prevalence of H. pylori (OR = 3.70; 95% CI = 2.66-5.14) than did that using the rapid urease test (RUT) (OR = 3.13; 95% CI = 2.26-4.34).

CONCLUSIONS

This paper demonstrated that CP was potentially correlated with oral H. pylori in adults and that oral H. pylori may be a possible risk factor for CP.

A Longitudinal, Population-Level, Big-Data Study of Helicobacter pylori-Related Disease across Western Australia

Helicobacter pylori, responsible for chronic ulcers and most stomach cancers, infects half of the world’s population. The Urea Breath Test (UBT) is one of the most accurate and reliable non-invasive methods for diagnosing active H. pylori infection. The objective was to use longitudinal, population-wide UBT data for Western Australia to look for H. pylori-related disease patterns. We collected 95,713 UBT results from 77,552 individuals for the years 2010–2015, likely representing all of the UBT samples analysed in Western Australia. Data collected also included sex, age and residential postcode. Other data reported here were inferred via a comparison with the 2011 Australian Census using a specially written Python program. While women appear to have more H. pylori-related disease than men, there is no difference in the disease rates once women’s higher rates of presentation for testing are taken into account. On the other hand, while the treatment strategy for H. pylori infection is generally very effective in Western Australia, failure of the first-line treatment is significantly more common in women than men. Migrants and Aboriginal Australians have elevated rates of H. pylori-related disease, while the rate for non-Aboriginal Australian-born West Australians is very low. However, no significant associations were found with other socio-economic indicators. We conclude that, for some people, H. pylori-related disease is not a solved problem.

Prevalence of Helicobacter pylori infection in newly arrived refugees attending the Migrant Health Service, South Australia

BACKGROUND

To determine the prevalence of Helicobacter pylori infection in the refugee population attending the Migrant Health Service, South Australia, identify demographic factors associated with infection and compare prevalence of infection in refugees with that of the nonrefugee population in Australia.

MATERIALS AND METHODS

Cross-sectional study conducted between October 2010 and August 2013. Monoclonal stool antigen testing for H. pylori infection is performed as part of a comprehensive health assessment for newly arrived refugees. The sample population included 922 adults and children. Outcome measures were (i) prevalence of H. pylori infection (ii) association between demographic factors such as sex, ethnicity and age, and H. pylori infection.

RESULTS

H. pylori infection was detected in 198 (21.5%) participants (95% CI 18.9%-24.3%). The odds of infection were lower in females OR 0.71 (95% CI 0.51-0.98) compared to males. Compared to Middle Eastern participants, the odds of infection were 1.75 (95% CI 1.17-2.62) times higher in African and 1.90 (95% CI 1.10-3.26) times higher in Burmese participants. Infection was not associated with age.

DISCUSSION AND CONCLUSION

H. pylori infection is common among newly arrived refugees. The long latency of infection to development of complications and the availability of testing and relatively effective eradication regimens all add weight to a decision to screen in this population.

Epidemiology, clinical impacts and current clinical management of Helicobacter pylori infection

Helicobacter pylori infection is a major cause of morbidity and mortality worldwide. More than 50% of the global population is estimated to be infected. Differences in prevalence exist within and between countries, with higher prevalence seen among people with lower socio-economic status. Most transmission of infection occurs early in life, predominantly from person to person in the family setting. H. pylori is the cause of most peptic ulcer disease, gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and causes symptoms in a subset of patients with functional dyspepsia. Choice of diagnostic test depends on the clinical context; urea breath tests and endoscopy with biopsy are the major diagnostic tools. Evidence-based indications for eradication of H. pylori infection are well documented. The most widely used and recommended eradication therapy in Australia is triple therapy comprising a proton pump inhibitor, amoxycillin and clarithromycin, usually for 1 week. Effective alternative regimens are available for patients with proven allergy to penicillin. Antimicrobial resistance is the major determinant of the outcome of eradication therapy. Trends in antibiotic resistance need to be monitored locally, but individual patient susceptibility testing is not usually necessary as it rarely guides the choice of therapy. The outcome of treatment should be assessed not less than 4 weeks after therapy. This is usually done with a urea breath test if follow-up endoscopy is not required. When first-line therapy fails, several proven second-line therapies may be used. Repeat first-line therapy and ad hoc regimens should be avoided. Overall cumulative eradication rates should approach 99%.

Prevalence and risk factors of Helicobacter pylori in Turkey: a nationally-representative, cross-sectional, screening with the ¹³C-Urea breath test

Background

Helicobacter pylori is an important global pathogen infecting approximately 50% of the world’s population. This study was undertaken in order to estimate the prevalence rate of Helicobacter pylori infections among adults living in Turkey and to investigate the associated risk factors.

Method

This study was a nationally representative cross sectional survey, using weighted multistage stratified cluster sampling. All individuals aged ≥18 years in the selected households were invited to participate in the survey. Ninety two percent (n = 2382) of the households in 55 cities participated; 4622 individuals from these households were tested with the ¹³C-Urea breath test. Helicobacter pylori prevalence and associated factors were analysed by the t test, chi square and multiple logistic regression with SPSS11.0.

Results

The weighted overall prevalence was 82.5% (95% CI: 81.0-84.2) and was higher in men. It was lowest in the South which has the major fruit growing areas of the country. The factors included in the final model were sex, age, education, marital status, type of insurance (social security), residential region, alcohol use, smoking, drinking water source. While education was the only significant factor for women, residential region, housing tenure, smoking and alcohol use were significant for men in models by sex.

Conclusion

In Turkey, Helicobacter pylori prevalence was found to be very high. Individuals who were women, elderly adults, single, had a high educational level, were living in the fruit growing region, had social security from Emekli Sandigi, were drinking bottled water, non smokers and regular alcohol consumers, were under less risk of Helicobacter pylori infection than others.

Genetic Analysis of cagA and vacA Genes in Helicobacter Pylori Isolates and Their Relationship with Gastroduodenal Diseases in the West of Iran

Background

Helicobacter pylori have different virulence factors which are associated with several gastroduodenal diseases; however, this association is variable in different geographical regions. Data of genotypes of Iranian H. pylori isolates are few.

Objectives

The aim of the current study was to investigate the cagA/vacA genotypes of Helicobacter pylori isolates and determine the relationship between these genotypes with respect to different gastric disorders in patients of Chaharmahalo Bakhtiarian.

Materials and Methods

In this cross-sectional study, gastric biopsies were taken from 200 patients with gastrodoudenal diseases. Histopathological features were recognized by specialist. The samples were subjected to PCR for detection and identification of ureC, cagA and vacA genes.

Results

The frequency of the vacA genotypes, sa1/m1, s1a/m1b, s1a/m2, s1b/m1a, s1b/m1b, s1b/m2, s1c/m1a, s1c/m1b, s1c/m2, s2/m1a, s2/m1b and s2/m2 were 27(6.6%), 8(4.3%), 45(28.04%), 7(3.7%), 5(2.5%), 10 (6.1%), 12 (7.4%), 4 (2.5%), 18(11%), 6(3.7%), 0 and 22(13.5%) respectively. The cagA gene was detected in 92% of strains. Based on our findings, it seemed that cagPAI and vacA s1 genotypes were associated with some gastric disorders in patients with H. pylori. In this region, the isolates carrying s1a/m2 were the most prevalent.

Conclusions

We found considerable relationship between s1a/m1a, s1a/m2, s2/m2 and s1c/m1a and some gastric disorders. Further studies about the role of H. pylori virulence factors and gastric disorders were recommended.

Prevalence of Helicobacter pylori in the adolescent oral cavity: dependence on orthodontic therapy, oral flora and hygiene

BACKGROUND

Helicobacter pylori (HP) infection usually occurs in childhood. While there are various studies on the prevalence of HP in dental plaque, ours is the first to analyze its prevalence during orthodontic therapy and its interaction with competitive bacteria in adolescents.

SUBJECTS AND METHODS

The prevalence of HP was examined before and during the first 12 weeks of orthodontic therapy with fixed appliances in 11 patients with a mean age of 12.7 years. A total of 93 plaque samples were analyzed using PCR. The data acquired at every consultation were the following: PCR analysis of dental plaque and (13)C urea breath tests for HP, quantitative analyses of saliva for Lactobacilli and Streptococcus mutans, the interproximal plaque index (API), and sulcus bleeding index (SBI).

RESULTS

The prevalence of HP in plaque was 82% before orthodontic therapy, dropping to 54% during therapy (t test, p≤0.05). In contrast to HP's prevalence, the Lactobacilli count rose (p≤0.05). The number of Streptococcus mutans bacteria in saliva decreased during orthodontic therapy (p≤0.05).

CONCLUSION

The prevalence of HP in dental plaque amounted to 82%. Orthodontic treatment did not reduce its prevalence. The prevalence of Lactobacilli was inversely proportional to that of HP.

Marked increase in proton pump inhibitors use in Australia

OBJECTIVES

To examine the trends in the prescribing of subsidized proton pump inhibitors (PPIs) and histamine receptor antagonists (H2RAs), in the Australian population from 1995 to 2006 to encourage discussion regarding appropriate clinical use. PPIs and H2RAs are the second highest drug cost to the publicly subsidized Pharmaceutical Benefits Scheme (PBS).

DESIGN

Government data on numbers of subsidized scripts, quantity and doses for PPIs and H2RAs were analysed by gender and age, dose and indication.

MAIN OUTCOME MEASURE

Drug utilisation as DDD [defined daily dose]/1000 population/day.

RESULTS

The use of combined PPIs increased by 1318%. Utilisation increased substantially after the relaxation of the subsidized indications for PPIs in 2001. Omeprazole had the largest market share but was substituted by its S-enantiomer esomeprazole after its introduction in 2002. There was considerable use in the elderly with the peak use being in those aged 80 years and over. The utilisation of H2RAs declined 72% over 12 years.

CONCLUSIONS

PPI use has increased substantially, not only due to substitution of H2RAs but to expansion in the overall market. Utilisation does not appear to be commensurate with prevalence of gastro-oesophageal reflux disease (GORD) nor with prescribing guidelines for PPIs, with significant financial costs to patients and PBS. This study encourages clinical discussion regarding quality use of these medicines.

Comparison of the virulence factors of Helicobacter pylori isolated in stomach and saliva in Iran

INTRODUCTION

Helicobacter pylori is a microaerophilic, spiral-shaped motile bacterium that is strongly associated with gastroduodenal diseases, but recently, dental plaque and saliva have been implicated as possible sources of H pylori infection. Two virulence factors that are expressed by the alleles of the cytotoxin genes, cagA and vacA, have been identified. The aim of this study was to compare cagA and vacA genotypes of H pylori between stomach and saliva in a same patient.

METHODS

This study was performed on antrum gastric biopsy specimens and saliva samples, which were obtained from 250 patients undergoing upper gastrointestinal tract endoscopy in Hagar Hospital of Shahrekord Township in Iran. Initially, H pylori strains were identified by rapid urease test; then, we applied polymerase chain reaction assay to analyze cagA and vacA genotypes of H pylori from both gastric and saliva specimens.

RESULTS

One hundred eighty-nine (75.6%) and 36 (14.4%) samples were H pylori positive in gastric and saliva samples, respectively. Evaluation of virulence factors in the 36 patients whose saliva and gastric samples were both positive for H pylori showed a great deal of cytotoxin genotypic diversity between stomach and saliva in the same patient; in fact, 14 patients (38.8%) had different H pylori strains in their saliva and gastric samples.

CONCLUSIONS

The data suggest that >1 H pylori strain may exist in stomach and saliva in the same patient.

Is the presence of Helicobacter pylori in dental plaque of patients with chronic periodontitis a risk factor for gastric infection?

BACKGROUND

Helicobacter pylori is considered to be a pathogen responsible for gastritis and peptic ulcers, and a risk factor for gastric cancer. A periodontal pocket in the teeth of individuals with chronic periodontitis may function as a reservoir for H pylori.

OBJECTIVE

The present study was undertaken to evaluate whether the presence of H pylori in the dental plaque of patients with and without periodontitis correlates with gastric involvement.

METHODS

A total of 101 patients with dyspepsia were included in the present study. Subjects were divided into periodontitis and nonperiodontitis groups. For the detection of H pylori in dental plaque, samples were collected from two teeth using a periodontal curette. Subgingival plaque was obtained by inserting two sterile paper points into periodontal pockets for 20 s. This was followed by an upper gastrointestinal endoscopy and antral biopsies.

RESULTS

Sixty-five per cent of patients had dental plaque positive for H pylori and more than 50% harboured the bacteria in their stomach. Periodontitis patients had a significantly higher percentage of H pylori in their dental plaque (79% versus 43%; P<0.05) and the stomach (60% versus 33%; P<0.05) than patients with no periodontitis. Additionally, 78% of patients from the periodontitis group versus only 30% from the nonperiodontitis group had a positive test result for the coexistence of H pylori in both dental plaque and the stomach.

CONCLUSION

Patients with poor oral hygiene have a higher prevalence of H pylori in dental plaque and in the stomach. This finding suggests that the oral cavity may be a reservoir for H pylori, and potentially a source of transmission or reinfection.

HELICOBACTER PYLORI INFECTION AND TREATMENT OUTCOME IN AN URBAN AUSTRALIAN POPULATION

BACKGROUND

To examine the rate of Helicobacter pylori infection in a group of symptomatic patients using rapid urease test and antral histology and report on their treatment outcomes.

METHODS

From a single-surgeon series in a tertiary teaching hospital, 200 consecutive symptomatic patients undergoing their first diagnostic upper gastrointestinal endoscopy during 2003-2004 were included in this retrospective audit. Campylobacter-like organism (CLO) test results were compared with the results of conventional histological examination plus Giemsa staining. Eradication rates and demographic data were collected.

RESULTS

One hundred and seventy-nine of 200 (89.5%) patients had antral biopsies for histology and for CLOtest. The CLOtest was positive in 31% (56/179) of patients. Thirty-two of 56 (57%) patients had an early-positive CLOtest (<24 h). The remaining 43% (24/56) of patients had a late-positive CLOtest (>24 h). Histological examination of the antral biopsy showed evidence of H. pylori in 28/56 (50%) patients with a positive CLOtest. H. pylori eradication therapy was prescribed in 51/56 (91%) patients with a positive CLOtest. Forty-five of 51 (88%) of these patients had a subsequent urea breath test. Urea breath test was positive in 17/45 (29%) patients after H. pylori eradication therapy was prescribed.

CONCLUSION

Rate of H. pylori in this series of symptomatic patients was 31%. As nearly half of the CLOtests became positive after 24 h, we suggest that the CLOtest should be re-examined 24 h after gastroscopy. Standard antral histology and CLOtest were in agreement in only 50% of cases, suggesting that the CLOtest is a more sensitive test. The failure rate of 29% for initial H. pylori eradication therapy reinforces the need for follow up after treatment.

Dyspepsia in homeless adults

GOALS

To determine the prevalence of and risk factors for dyspepsia in a representative sample of homeless persons using shelters in Toronto, Canada.

BACKGROUND

Homeless people have many risk factors for dyspepsia, but little information is available on gastrointestinal symptoms in this population.

STUDY

Cross-sectional survey of a representative sample of 100 homeless adults, with serologic testing for Helicobacter pylori infection.

RESULTS

The prevalence of moderate, severe, or very severe symptoms within the past 3 months was 18% for upper stomach pain and 59% for any dyspeptic symptom. Nonwhite ethnicity (odds ratio, 3.5; 95% confidence interval, 1.1-10.9) and a history of gastrointestinal disease (odds ratio, 8.6; 95% confidence interval, 2.5-29.6) were significantly associated with moderate to very severe upper stomach pain. H. pylori infection was identified in 31% of participants but was not significantly associated with dyspepsia.

CONCLUSIONS

Dyspepsia is a common problem among homeless adults in Toronto. The presence of upper stomach pain is most strongly associated with a history of gastrointestinal disease.

Prevalence of Helicobacter pylori infection and associated factors among adults in Southern Brazil: a population-based cross-sectional study

BACKGROUND

Helicobacter pylori (Hp) infection is associated with several upper gastrointestinal disorders. Local data on the epidemiology of the infection are scarce in Brazil. The purpose of this study is to measure the prevalence rate and to explore the associated factors among the adult population living in Pelotas, a southern Brazilian city.

METHODS

This was a population-based cross-sectional study. Through a multi-stage sampling method all individuals 20 years and over living at the selected households at the urban area of the city were interviewed regarding past and current socio-economic indicators; demographic characteristics; nutritional and behavioural habits; and history of upper gastrointestinal symptoms.Hp infection was ascertained through the 13C-UBT. Due to the high prevalence, data were analysed through robust Poisson regression. All analyses took into account the family clustering of the data.

RESULTS

Among 563 eligible individuals, 363 agreed to perform the 13C-UBT (refusal rate of 35.5%). Refusals were associated with female sex, consumption of mate drinking, and presence of upper gastrointestinal symptoms. The prevalence rate of H. pylori infection was 63.4% (95%CI 59.3%-69.3%). In crude analyses, prevalence was associated with increasing age, non-white skin colour, lower current family income, lower education level, higher size of the family, low socio-economic conditions in childhood, higher number of siblings and attendance to day-care centres in childhood, and presence of dyspeptic symptoms. In adjusted analysis the level of education of the father was inversely associated with the infection, whereas number of siblings and attendance to day-care centre in childhood were directly associated with it. Non-white skin colour remained significantly associated with increased prevalence even after allowing for past and current socio-economic characteristics, age and sex. Compared to non-symptomatic individuals, those reporting dyspeptic symptoms presented a higher prevalence of the infection even after allowing for current and past socio-economic conditions, ethnicity, age, and sex.

CONCLUSION

Hp infection is as common among adults in southern Brazil as it is in other developing countries. Socio-economic conditions in childhood besides ethnicity and presence of dyspeptic symptoms were the factors significantly associated with the infection.

Helicobacter pylori infection in different generations of Hispanics in the San Francisco Bay Area

To quantify the contributions of household and environmental factors to Helicobacter pylori infection, the authors examined H. pylori infection among several generations of Hispanics in the San Francisco Bay Area. Between 2000 and 2004, household members were tested for H. pylori and interviewed about demographic factors and household pedigree. An immigrant was defined as someone born in Latin America with at least one Latin America-born parent; a first-generation US-born Hispanic was defined as someone born in the United States with at least one Latin America-born parent; and a second-generation US-born Hispanic was defined as someone born in the United States with at least one US-born parent. Prevalences of H. pylori in immigrants and first- and second-generation US-born Hispanics were 31.4% (102/325), 9.1% (98/1,076), and 3.1% (2/64), respectively. Compared with second-generation US-born Hispanics, the age-adjusted odds ratios for H. pylori were 9.70 (95% confidence interval (CI): 1.57, 60.00) for immigrants and 4.32 (95% CI: 0.69, 26.96) for first-generation US-born Hispanics (p(trend) < 0.001). These odds ratios decreased to 6.19 (95% CI: 1.13, 33.77) and 3.24 (95% CI: 0.59, 17.82), respectively, after adjustment for parental infection (odds ratio (OR) = 2.94, 95% CI: 1.59, 4.38), low education (OR = 1.76, 95% CI: 1.20, 2.68), and crowding (OR = 1.23, 95% CI: 0.84, 1.79). Both the household and birth-country environments probably contributed to declining H. pylori prevalence among successive generations of Hispanics.

Tooth loss and Helicobacter pylori seropositivity: the Newcastle Thousand Families Cohort Study at age 49-51 years

BACKGROUND

Helicobacter pylori, one of the commonest chronic bacterial infections of humankind, is an important risk factor for gastric carcinoma. It has also been suggested to be present in dental plaque. This study investigated the potential link between the number of teeth lost and H. pylori seropositivity at age 50 years.

METHODS

H. pylori seropositivity at age 50 years was investigated among 334 individuals born in Newcastle upon Tyne, United Kingdom, in May and June 1947 and related to the number of teeth lost, after adjusting for socioeconomic status.

RESULTS

The unadjusted risk of being seropositive for H. pylori increased with increasing number of teeth lost (odds ratio per tooth 1.03, 95% confidence interval 1.01-1.06, p = .019). However, after adjustment for socioeconomic status at birth and at age 50 years, the relationship was no longer significant (p = .36).

CONCLUSIONS

Our results, obtained using prospectively collected data, suggest that any relationship between poor oral health and seropositivity to H. pylori may be due to both tooth loss and H. pylori colonization being associated with socioeconomic status and related factors.

Tooth loss, pancreatic cancer, and Helicobacter pylori

BACKGROUND

Poor dental health has been associated with increased risks of oral, esophageal, and gastric cancer and may also be associated with pancreatic cancer. In addition, Helicobacter pylori has been found in dental plaque and has been associated with periodontal disease and pancreatic cancer.

OBJECTIVE

The objective was to investigate prospectively the relation between dentition history and pancreatic cancer in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study cohort in Finland and the association between dentition history and H. pylori seropositivity in a cross-sectional sample of subjects without cancer (n = 475) from the same cohort.

DESIGN

Of the 29,104 male smokers aged 50-69 y in the cohort for whom there were complete data, 174 developed pancreatic cancer from 1985 to 1997. Cox proportional hazard models were used to estimate age-, smoking-, education-, urban living-, and height-adjusted hazard ratios and 95% CIs for pancreatic cancer, and logistic regression models were used to estimate age- and education-adjusted odds ratios for H. pylori carriage.

RESULTS

Tooth loss was positively associated with pancreatic cancer (edentulous compared with missing 0-10 teeth: hazard ratio = 1.63; 95% CI: 1.09, 2.46; P for trend = 0.02) but was not significantly associated with H. pylori seropositivity (edentulous compared with missing 0-10 teeth: odds ratio = 1.30; 95% CI: 0.73, 2.32; P for trend = 0.37).

CONCLUSION

Additional studies are needed to evaluate the association between tooth loss and pancreatic cancer, as well as cancers at other gastrointestinal sites, particularly with respect to possible biological mechanisms.

Oral Helicobacter pylori: can we stomach it?

Helicobacter pylori infection is one of the most common in man. The bacterium primarily resides in the human stomach, where it plays a significant role in gastric disease. If the spread of H. pylori is to be prevented, an understanding of the transmission process is essential. The oral cavity has been proposed as a reservoir for gastric H. pylori, which has been detected by culture and PCR in both dental plaque and saliva. This review will discuss the evidence for the role of the oral cavity in the transmission of gastric H. pylori. Moreover, the difficulties encountered in addressing this topic, possible directions for future research, and the implications for the dental profession are discussed.

Helicobacter pylori infection in the Australian community: current prevalence and lack of association with ABO blood groups

AIMS

To assess the current prevalence of Helicobacter pylori infection in an Australian urban population sample and to relate this to age, gender and ABO and Rhesus blood groups.

METHODS

We performed a prospective epidemiological survey of H. pylori serological status in 500 consecutive voluntary blood donors who presented for the purpose of blood donation at the central -Melbourne branch of the Australian Red Cross Blood Service, Victoria, Australia, and gave a Melbourne suburban home address.

RESULTS

The overall prevalence of specific anti-H. pylori IgG antibodies in this cohort was 32% (95% confidence interval = 28-36%) and H. pylori sero-positivity increased with age. The rate of H. pylori infection was not significantly different in men and women, with anti-H. pylori IgG anti-bodies detected in 35% (97/277) of men compared with 28% (63/233) of women (P = 0.12). Similarly, H. pylori serological status was not significantly different between subjects of different ABO (P = 0.18) or Rhesus blood groups (P = 0.55).

CONCLUSION

This study showed that, contrary to expectation, the updated prevalence of H. pylori seropositivity (32%) in this Melbourne sample is at least as high as that found in previous Australian studies over the past 19 years. Seropositivity increased with age, and was not related to gender, confirming the infection pattern seen in other developed nations. Despite epidemiological evidence of increased peptic ulcer disease in ABO blood group O subjects, and recent evidence that H. pylori adhesion to gastric epithelial cells is mediated by blood group epitopes, no significant association between blood groups and H. pylori serological status was detected.

Seroepidemiology of Helicobacter pylori infection in Guadeloupe

854 sera collected from blood donors in Guadeloupe were screened for Helicobacter pylori immunoglobulin G antibodies by a commercial enzyme-linked immunosorbent assay kit. The overall prevalence was 55.2%; it increased significantly with age from 36.1% at 18-19 years to 63.7% at 50-59 years (P = 0.003).

Helicobacter pylori infection in rural China: demographic, lifestyle and environmental factors

BACKGROUND

Although Helicobacter pylori is one of the most common human bacterial infections worldwide, its mode of transmission is unclear.

METHODS

To investigate possible associations between H. pylori infection and demographic, lifestyle, and environmental factors in a rural Chinese population, a cross-sectional survey was administered to 3288 adults (1994 seropositive, 1019 seronegative, 275 indeterminate) from 13 villages in Linqu County, Shandong Province, China.

RESULTS

Helicobacter pylori prevalence was elevated for: infrequent handwashing before meals (OR = 1.7, 95% CI: 1.0-3.0), crowding (i.e. sharing a bed with >2 people [OR = 2.3, 95% CI: 1.3-4.2]), washing/bathing in a pond or ditch (OR = 1.5, 95% CI: 1.0-2.4), and medium (OR = 1.6, 95% CI: 1.3-2.0) and low (OR = 2.3, 95% CI: 1.9-2.9) compared to high village education level, and reduced for never being married or divorced (OR = 0.4, 95% CI: 0.2-1.0). There was also a suggestion that source of drinking water, especially water from a shallow village well might be related to H. pylori seropositivity. There was no evidence of an association between H. pylori prevalence and alcohol or tobacco use, raw fruit and vegetable intake, or individual social class measures.

CONCLUSIONS

The results of this study suggest that person-to-person transmission is the most plausible route of H. pylori infection in this rural Chinese population, but waterborne exposures deserve further investigation.

Helicobacter pylori infection and fasting plasma glucose concentration

BACKGROUND

Helicobacter pylori infection raises basal and meal stimulated serum gastrin concentrations and lowers iron stores, which may in turn reduce fasting plasma glucose concentrations in the population.

AIM

To determine whether H pylori infection leads to lower fasting plasma glucose concentrations in the population.

METHODS

One hundred and seventy three women and 165 men, randomly selected from the electoral rolls of an Australian city, participated in a cardiovascular risk factor survey. Plasma glucose concentrations and H pylori IgG antibody titres were measured. Non-fasting subjects and pregnant women were excluded, as were known diabetics, whose plasma glucose concentrations would be affected by diet and/or medications. Fasting plasma glucose concentrations were logarithmically transformed and the relation with H pylori infection, adjusting for age and other confounding factors, was determined for men and women separately by analyses of variance.

RESULTS

Helicobacter pylori infection was significantly associated with fasting plasma glucose concentration among women. Infected women had a lower mean fasting plasma glucose concentration (5.2 mmol/litre; range, 3.9-8.2) than did non-infected women (5.4 mmol/litre; range, 3.9-11.1).

CONCLUSIONS

Helicobacter pylori infection may lead to lower fasting plasma glucose concentrations among women and should be considered when interpreting concentrations bordering on diabetes.

Review article: the transmission of Helicobacter pylori from stomach to stomach

The mode of transmission of Helicobacter pylori is largely unknown and is a matter of circumstantial evidence and speculation rather than fact. However, the principle evidence is of two sorts: the epidemiological data, providing evidence of possible risk factors associated with transmission, and the identification of potential sources from which H. pylori could be acquired. Evidence exists for several potential sources of infection and several possible modes of transmission, and it is feasible that the transmission of H. pylori varies according to the cultural and demographic circumstances. However, the most likely recognized source for H. pylori is the human stomach, although it is not known by what route the organism is transmitted to the stomach. Evidence suggests close personal contact is important and that acquisition occurs mainly in childhood. This article reviews the evidence for the source of infection and the route of transmission of H. pylori.

Recent developments in the epidemiology of Helicobacter pylori

Prevalence determinations have been performed around the world, and regardless of how exotic a location, H. pylori is found in a substantial proportion of the population. H. pylori remains among the most universal of infections. Understanding of some features of infection has changed. Infection can be gained and lost at rates higher than previously realized. Oral-oral and oral-fecal transmission account for most, if not nearly all, cases of infection. H. pylori infection has declined rapidly in developed countries, which probably has contributed to declines in duodenal ulcer disease and gastric cancer. The full health implications of the potential elimination of infection are unknown.

Helicobacter pylori infection is not a correlate of plasma fibrinogen in the Australian population

Plasma fibrinogen concentration is an important independent risk factor for cardiovascular disease. Studies into whether Helicobacter pylori infection and fibrinogen are associated have yielded inconsistent results. Despite the geographical variation in fibrinogen and prevalence of H. pylori infection, all studies to date have been undertaken in the United Kingdom or Italy. The association between H. pylori infection and fibrinogen was investigated in 324 adults, 65% of a random sample, in an Australian regional city. The mean plasma fibrinogen concentration in 98 infected participants (2.52 g/l) was similar to that in 226 non-infected subjects (2.58 g/l, P = 0.51); 95% confidence interval on the difference was -0.23-0.11 g/l. After including all potential confounding factors in a backward multiple linear regression analysis, H. pylori was still not associated with fibrinogen (P = 0.084). Any association between H. pylori and cardiovascular disease in Australia is not mediated through fibrinogen.

Helicobacter pylori infection: an added stressor on iron status of women in the community

OBJECTIVE

To explore a possible association between Helicobacter pylori infection and iron status.

DESIGN

Cross-sectional study.

SETTING

Ballarat (a major regional city in Victoria), population 78000, October November 1997.

PARTICIPANTS

160 women and 152 men, a subsample of participants in a cardiovascular disease risk factor prevalence survey for whom frozen plasma was available.

MAIN OUTCOME MEASURES

H. pylori IgG antibody status by enzyme immunoassay; iron intake; plasma iron, transferrin and ferritin concentrations.

RESULTS

28% of women and 33% of men were infected with H. pylori. The mean (SEM) plasma ferritin concentration of infected women (59.3 [7.6] microg/L) was significantly lower than for non-infected women (88.8 [7.9] microg/L; P=0.002), after adjusting for age. Mean daily dietary iron intakes were similar in infected and non-infected women.

CONCLUSIONS

H. pylori infection appears to be an additional stressor on women's iron status, but the mechanism remains to be determined.