Relation between infection with Helicobacter pylori and living conditions in childhood: evidence for person to person transmission in early life

Early Helicobacter pylori colonisation: the association with growth faltering in The Gambia

BACKGROUND

Helicobacter pylori is one of the commonest causes of chronic infection of mankind, yet the natural history of acute infection is poorly understood. Some studies suggest that gastric colonisation with H pylori is associated with suboptimal nutrition and growth in childhood.

AIMS

To describe the clinical features of early H pylori colonisation and assess its role in the development of infant malnutrition and growth faltering.

METHODS

Two consecutive prospective longitudinal cohort studies were conducted at the Medical Research Council Laboratories in a rural community in The Gambia, West Africa. The first birth cohort of 125 infants was followed by a second of 65 children from the same community. H pylori colonisation was detected by sequential 13C urea breath tests, and infant growth was monitored by serial measurements.

RESULTS

Children with early H pylori colonisation became significantly lighter, shorter, and thinner than their peers in late infancy. The association was found in both cohorts. No socioeconomic or demographic confounding variables were identified to explain this, and the weight deficit was no longer detectable when the children were aged 5-8 years.

CONCLUSIONS

Results suggest that H pylori colonisation in early infancy predisposes to the development of malnutrition and growth faltering, although the effect did not persist into later childhood.

Appropriate strategies for testing and treating Helicobacter pylori in children: when and how?

Helicobacter pylori infection is acquired primarily during childhood and carries a significant lifetime risk for morbidity. In developing countries, approximately 70% of children are infected with the bacterium by their 15th birthday. In the United States, the rate of H pylori infection among children varies widely--approximately 10% of all 10-year-olds are infected; however, this figure is substantially higher among populations of immigrant children and children born of recent immigrants to the United States. H pylori transmission is primarily "person-to-person" via fecal-oral, gastric-oral, or oral-oral routes, with evidence suggesting contaminated water as a potential source of infection. Risk factors for infection in childhood include an infected family member, having > or =2 siblings, crowded living conditions, lower socioeconomic means, and attendance at a daycare facility. The natural history of H pylori infection includes an increased lifetime risk for peptic ulcer and gastric adenocarcinoma or lymphoma. In children and adults who develop H pylori-related peptic ulcer, cure of the infection is associated with a <5% rate of ulcer recurrence. The ideal mode of H pylori detection among children is unclear--currently available serology and whole blood tests are unreliable, while the urea breath test and stool antigen tests have not been studied adequately. Children with confirmed H pylori-related peptic ulcer disease, iron-deficiency (sideropenic) anemia, or a first-degree relative with gastric cancer should be treated for the infection using 1 of 3 available 10- to 14-day triple therapy regimens recommended by the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition.

High seroprevalence of Helicobacter pylori infection in non-institutionalised children with mental retardation

Eighty-four children with mental retardation (34 boys, 50 girls; age range 2-18 years, median 6 years) and 84 age- and gender-matched outpatient controls were studied. All children were living at home, had never stayed in an institution, and came from the same urban area. Seropositivity for Helicobacter pylori was found in 42 (50%) of 84 mentally retarded children and 16 (19%) of 84 controls (p < 0.01). Socio-economic factors did not differ between the two groups. The findings indicated that a higher prevalence of H. pylori infection occurs in children with mental retardation, regardless of whether they are institutionalised.

Age at acquisition of Helicobacter pylori infection: comparison of two areas with contrasting risk of gastric cancer

BACKGROUND

Helicobacter pylori infection is usually acquired during childhood and is a known risk factor for the development of gastric malignancies in adulthood. It has been reported that early age at first infection may determine a neoplastic outcome in adults. The purpose of this study was to determine the prevalence of Helicobacter pylori infection in children residing in areas with high (Pasto) and low risk (Tumaco) of gastric cancer in Colombia to evaluate whether differences in the age of acquisition of H. pylori infection were present in the two populations.

MATERIALS AND METHODS

The study sample was based on a census taken in 1999. Using the (13)C-urea breath test, we compared the prevalence of H. pylori infection among children aged 1-6 years.

RESULTS

Among 345 children in Pasto, 206 (59.7%) were H. pylori-positive, compared with 188 (58.6%) among 321 children in Tumaco. The two populations share a common pattern of very early age at infection and marked increase in prevalence during the first 4 years of life. No differences in any one year were observed when comparing the two groups.

CONCLUSIONS

The prevalence of infection was similarly high and increased with age in both populations. In these populations the age of acquisition of H. pylori after 1 year of age does not appear to be a primary factor responsible for the differences in the rates of gastric cancer incidence in adults. Previous findings in adults showed lower prevalence of the most virulent genotypes in Tumaco compared to Pasto, and bacterial virulence may play a key role in determining cancer outcome.

Childhood H. pylori: disappearing disease or chronic infection?

Helicobacter pylori is one of the commonest chronic bacterial infections worldwide. It is acquired during childhood and its persistence has implications for health in later life. In adults, it is the principle cause of duodenal ulcer disease and there is evidence of an association between H. pylori and gastric cancer. However, most colonized people are asymptomatic. The prevalence of H. pylori increases with age but there is a striking difference between the rates in developed and developing countries. As no significant non-human or environmental source for this infection has been identified, person to person spread is almost certainly the main mode of transmission. Community nurses should be aware of this micro-organism as a potential cause of illness in children, and that they can play a role in promoting hygiene practices and educating families so that the risk of acquisition may be reduced. This review discusses the clinical features, prevalence, risk factors for transmission, diagnosis and treatment of H. pylori.

Review article: impact of Helicobacter pylori on society-role for a strategy of 'search and eradicate'

Helicobacter pylori infection is causally related to gastric cancer, a malignancy associated with high morbidity and poor prognosis, and to peptic ulcer disease, a disease with high morbidity and modest mortality. Theoretically, H. pylori eradication is the most practical means of preventing gastric cancer and peptic ulcer disease. From a public policy perspective, the current evidence is insufficient to assess accurately the magnitude of the benefits of a universal 'search and treat' approach. Nonetheless, it is possible to identify high-risk patients for whom testing for the presence of H. pylori infection, with the intention-to-treat infected individuals is currently indicated. This list includes patients with ulcers or dyspepsia, first-degree relatives of patients with peptic ulcer or gastric cancer, gastric cancer patients after potentially curative resection of their gastric cancer, patients in whom long-term acid antisecretory therapy or long-term nonsteroidal anti-inflammatory drug therapy (including low-dose aspirin) is planned, and finally those who desire testing. Population screening among asymptomatic individuals with a high risk of gastric cancer, such as Korean- and Japanese-Americans, appears logical, but from a public health perspective should be done as a component of controlled intervention studies. There are no known H. pylori infections without risk of a symptomatic outcome, therefore screening represents a rational strategy for cancer prevention. Adoption of such a policy will require carefully balancing the costs of the programme with its benefits.

The incidence of Helicobacter pylori acquisition in children of a Canadian First Nations community and the potential for parent-to-child transmission

BACKGROUND AND AIMS

We have previously reported that Wasagamack, a Canadian First Nations community has a seroprevalence rate of Helicobacter pylori of 95% and a prevalence rate among children aged 0-12 years as measured by stool antigen testing of 56%. We aimed to determine the rate of infection acquisition and possible modes of transmission of childhood Helicobacter pylori infection in this Canadian First Nations community.

METHODS

Children who were previously negative for H. pylori by stool antigen testing in August 1999 were eligible for enrollment in August 2000; 50 (77%) eligible children underwent stool collection. H. pylori stool antigen status was tested using the Premier Platinum HpSA test. Drinking water samples, maternal saliva, breast milk, local berries and flies were tested by three complementary H. pylori-specific PCR assays. Soothers or bottle nipples, collected from 16 children whose H. pylori stool antigen status was determined, were bathed in sterile water and this water was tested by PCR.

RESULTS

Stool was positive for H. pylori in 16% (8/ 50) of children retested. Five had no other siblings infected and three had infected siblings. The mothers of all children infected were positive for H. pylori. The median age of newly infected children was 6 years (range 1-13 years). By PCR, 78% (18/23) mothers' saliva samples, 69% (11/16) soother water samples and 9% (1/11) water samples from infected homes tested positive. All of 24 sequenced PCR-produced DNA fragments from samples showed 99% homology with that from ATCC type strain H. pylori.

CONCLUSIONS

The rate of childhood H. pylori acquisition was 16% over 1 year, and was not dependent on number of siblings infected. The finding of homologous H. pylori DNA in saliva and in soother water suggests the possibility of human to human transmission, particularly via an oral-oral route. Thus, there is the potential for further investigations in this population and other endemic communities that are directed at prevention of infection transmission via this modality.

Prevalence of Helicobacter pylori infection in children from an urban community in north-east Brazil and risk factors for infection

OBJECTIVES

To investigate the prevalence of Helicobacter pylori infection in a randomly selected population of children from a low income community in Brazil and the risk factors for infection.

DESIGN

A cross-sectional, randomised study of prevalence and risk factors.

SUBJECTS

Children living in an urban community in north-east Brazil.

METHODS

H. pylori infection was determined using the C-urea breath test. Risk factors were assessed using a structured interview schedule.

RESULTS

The overall prevalence of H. pylori was 56% (197/353). The infection was most common for those aged 12-14 years. In this group 75.4% (49/65) (95% CI, 63.1-85) of all children were positive for H. pylori, while in children less than 2 years of age 35.1% (13/37) (95% CI, 20.2-52.5) were positive. The prevalence of H. pylori increased significantly with age (P < 0.0001). In the bivariate analysis, a significant difference was found in the prevalence of H. pylori infection and age, number of persons per room, the number of children per household, cup sharing, and type of drinking water (P < 0.05). However, after logistic regression modelling only age (odds ratio (OR) = 1.3; 95% confidence interval (CI), 1.07-1.65), and number of persons per room (OR = 2.58; 95% CI, 1.4-4.6) were risk factors for H. pylori infection.

CONCLUSIONS

H. pylori is highly prevalent among children in a north-eastern Brazilian community characterised by poor living conditions, and this infection is largely acquired during early childhood. The infection increased with age, and domestic overcrowding. Further longitudinal studies must examine in depth the possible modes of transmission of the organism in young children.

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Prevalence and identification of tetracycline-resistant oral bacteria in children not receiving antibiotic therapy

The prevalence of tetracycline-resistant oral bacteria in healthy 4- and 6-year-old children who had not received antibiotics during the 3 months prior to sampling was investigated. Of the 47 children sampled, 46 harboured tetracycline-resistant bacteria. The median proportion of cultivable anaerobic and aerobic oral bacteria resistant to tetracycline was 1.1% and the MIC50 of these was 64 microg ml(-1). The majority (56%) of tetracycline-resistant bacteria were resistant to at least one other antibiotic, usually erythromycin. The most commonly identified tetracycline-resistant bacteria were the oral streptococci (65%), the next most prevalent groups were Veillonella spp. (10%) and Neisseria spp. (9%). The most frequently identified tetracycline resistance determinant was tet(M). The results of this study have shown that tetracycline-resistant oral bacteria were widespread amongst the children studied.

Burden of Helicobacter pylori and H. pylori-related diseases in developed countries: recent developments and future implications

Helicobacter pylori colonizes the gastric mucosa. H. pylori infection is the main cause of peptic ulcer and gastric malignancy. This review gives an overview on the epidemiology of H. pylori infection and H. pylori-associated diseases in the developed world, mainly Europe, and it discusses very recent developments with regard to the prevalence and its future implications for H. pylori-associated diseases.

Prevalence and risk factors associated with Helicobacter pylori infection in native populations from Brazilian Western Amazon

We evaluated the prevalence of, and factors associated with, Helicobacter pylori infection in 222 subjects from 3 distinct communities of native populations (Uru-Eu-Wau-Wau Indians and 2 riverine communities living on the banks of the Machado river and in Portuchuelo) living in isolation in the rainforest of Brazilian Western Amazon. The overall prevalence was 78.8% (95% CI 72.7-83.9). The prevalence was higher in the Machado river community compared with Portuchuelo (chi2 = 3.84, P = 0.05), but no significant difference was observed between the Machado river community and the Uru-Eu-Wau-Wau Indians. Logistic regression showed that residential crowding and age were factors associated with the presence of H. pylori infection. Acquisition of the bacterium started early in life and by the age of 2 years 50% of children were infected. The prevalence increased with age, reaching near universal levels during adulthood (97.9%). Residential crowding was high with a global index of 3.3 persons/room (SD = 1.8), varying significantly between the 3 communities (P = 0.001). These data provide further evidence supporting direct person-to-person spread of the bacterium.

Helicobacter in the developing world

Helicobacter pylori in the developing world is associated with many unique challenges not encountered in an industrialized setting. The 20% prevalence of infection with H. pylori among adolescents in the United States pales in comparison to infection rates exceeding 90% by 5 years of age in parts of the developing world. While H. pylori within the developed world is associated with gastritis, which may lead to peptic ulcer and gastric carcinoma, the infection in the developing world appears to also be linked with chronic diarrhea, malnutrition and growth faltering as well as predisposition to other enteric infections, including typhoid fever and cholera. Once identified, treatment of H. pylori within the developing world presents increased difficulties due to the frequency of antibiotic resistance as well as the frequency of recurrence after successful treatment. Control, and possibly eradication, of H. pylori could likely be achieved through increased standards of living and improved public health, as it has in the industrialized world. However, these measures are distant objectives for most developing countries, making long-term control of the organism dependent on the development and administration of an effective vaccine.

Age-specific Helicobacter pylori seropositivity rates of children in an impoverished urban area of northeast Brazil

We determined age-specific Helicobacter pylori seropositivity rates of 166 children and 39 mothers in an urban shantytown in northeast Brazil. Seropositivity rates increased from 23.1% at 0 to 11 months of age to only 39.3% by 96 to 131 months of age and were 82.1% at maturity. We observed no correlation between the seropositivity of the mothers and the seropositivity of their children.

Helicobacter pylori infection in Swiss adolescents: prevalence and risk factors

OBJECTIVE

This investigation sought to study the influence exerted by demographic and socioeconomic factors on the prevalence of infection in adolescents living in Switzerland.

DESIGN

Epidemiological study spanning 3 years.

METHODS

We included 196 15- to 16-year-old adolescents from a north-eastern Swiss city in our study, recruited by the school health service during a medical check-up in the years 1999, 2000 and 2001. infection was detected by ELISA using 2nd generation anti- IgG antibodies. Demographic and socioeconomic data were collected by questionnaire.

RESULTS

infection was found in 19 of the 196 (9.7%) tested adolescents. tested positive in, respectively, 13 (7.3%) of the 176 natives and six (30%) of the 20 (P = 0.01 chi-squared) subjects from foreign countries. infection was significantly highly correlated with demographic factors but did not correlate with most of the socioeconomic factors.

CONCLUSION

The rate of infection among Swiss adolescents is one of the lowest in Europe. Nevertheless, an important disparity is evident between the rate of infection observed in the native population and that among immigrants. High living standards available to the majority of the population may explain the minor influence of socioeconomic factors on infection in our country.

Inverse relationship between alcohol consumption and active Helicobacter pylori infection: the Bristol Helicobacter project

OBJECTIVE

The aim of this study was to examine whether smoking or consumption of alcohol or coffee is associated with active Helicobacter pylori (H. pylori) infection.

METHODS

This was a cross-sectional population study conducted as part of a randomized controlled trial of H. pylori infection eradication in southwest England. A total of 10,537 subjects, recruited from seven general practices, underwent 13C-urea breath testing for active infection with H. pylori and provided data on smoking, usual weekly consumption of alcohol, and daily intake of coffee.

RESULTS

Smoking or coffee consumption were not related to active H. pylori infection. Total alcohol consumption was associated with a small, but not statistically significant, decrease in the odds of infection. After adjustment for age, sex, ethnic status, childhood and adult social class, smoking, coffee consumption, and intake of alcoholic beverages other than wine, subjects drinking 3-6 units of wine/wk had an 11% lower risk of H. pylori infection compared with those who took no wine: OR = 0.89, 95% CI = 0.80-0.99. Higher wine consumption was associated with a further 6% reduction in the risk of infection: OR = 0.83, 95% CI = 0.64-1.07. Intake of 3-6 units of beer (but no greater intake) was associated with a similar reduction in the risk of infection when compared to no beer intake (OR = 0.83, 95% CI = 0.75-0.91).

CONCLUSIONS

This study indicates that modest consumption of wine and beer (approximately 7 units/wk) protects against H. pylori infection, presumably by facilitating eradication of the organism.

Role of partner's infection in reinfection after Helicobacter pylori eradication

AIM

To evaluate whether the Helicobacter pylori status of the patient's spouse plays a role in reinfection after eradication success, and to assess the possibility of transmission of H. pylori among partners by using molecular methods.

METHODS

We studied prospectively 120 patients in whom H. pylori had been eradicated. Endoscopy with biopsies and a 13C-urea breath test were performed 1 month after completing therapy. The breath test was repeated in all patients at 6 and 12 months. At the 1-year follow-up visit (or before if reinfection occurred), a breath test was also performed on the patient's partner. Samples for the molecular study included gastric biopsies from patients and gastric content obtained by the string test from partners. The heterogeneity of ureC was studied by enzymatic digestion with MseI and HhaI enzymes of a polymerase chain reaction (PCR) product of 1179 bp belonging to the ureC gene, and different band patterns were generated after electrophoresis.

RESULTS

Four reinfections were diagnosed at 6 months, and four were diagnosed from 6 to 12 months (incidence 6.8% per patient-year). Seven of eight (87%) of the reinfected patients' spouses were infected, but H. pylori infection of spouses was also frequent (76%) among non-reinfected patients. In the multivariate analysis, age of the patient (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.87 to 0.99, P < 0.05), delta(13)CO(2) value after therapy (OR 2.51, 95% CI 1.14 to 5, P < 0.05), and therapy regimen (OR 6.23, 95% CI 1.25 to 31, P < 0.05) were the only variables that correlated with H. pylori recurrence. However, family variables (H. pylori status of spouse, breath test value of spouse, length of time couple had lived together, number of children living at home, household density) did not correlate with recurrences. Thus, the OR for the H. pylori status of spouse (adjusted by age, delta(13)CO(2) and therapy) was 2.93 (95% CI 0.29 to 29, P > 0.05). H. pylori recurrence occurred in seven of 92 (7.6%) patients when the spouse was infected (95% CI 3.7% to 15%), and in one of 28 (3.6%) patients when the spouse was H. pylori-negative (95% CI 0.6% to 18%) (P > 0.05; however, the power of this comparison was < 20%). Therefore, even if the spouse was infected, 92.4% of patients will remain uninfected 1 year after H. pylori eradication. Three reinfected patients (at 1 year) and their partners (also infected) agreed to have the endoscopy and string test performed, respectively. The molecular study revealed that H. pylori strains involved were different in all cases.

CONCLUSION

Recurrence of H. pylori infection seems to be relatively infrequent, even if the patient's spouse is H. pylori-positive. The molecular study demonstrated that the strains in reinfected patients and their partners are different, suggesting that the patient's partner does not act as a reservoir for H. pylori reinfection.

[Epidemiological aspects of Helicobacter pylori infection in childhood and adolescence]

The scope of the review is to study the epidemiological aspects of Helicobacter pylori infection and its importance during childhood and adolescence, focusing on incidence, prevalence, transmission and risk factors. The study's references included the following databases: LILACS (PAHO/ Bireme), MEDLINE, the US's National Library of Medicine and the thesis developed at University of São Paulo for the period 1983 to 1999. It was noted that Helicobacter pylori infection is mainly acquired during childhood, age-related prevalence, main risk factors are associated to low socioeconomic status, and its transmission mechanism remains unclear.

Relation of adult lifestyle and socioeconomic factors to the prevalence of Helicobacter pylori infection

INTRODUCTION

The influence of adult socioeconomic status, co-habitation, gender, smoking, coffee and alcohol intake on risk of Helicobacter pylori infection is uncertain.

METHODS

Subjects between aged 40-49 years were randomly invited to attend their local primary care centre. Participants were interviewed by a researcher on smoking, coffee and alcohol intake, history of living with a partner, present and childhood socioeconomic conditions. Helicobacter pylori status was determined by 13C-urea breath test.

RESULTS

In all, 32 929 subjects were invited, 8429 (26%) were eligible and 2327 (27.6%) were H. pylori positive. Helicobacter pylori infection was more common in men and this association remained after controlling for childhood and adult risk factors in a logistic regression model (odds ratio [OR] = 1.15; 95% CI: 1.03-1.29). Living with a partner was also an independent risk factor for infection (OR = 1.30; 95% CI: 1.01-1.67), particularly in partners of lower social class (social class IV and V-OR = 1.47; 95% CI: 1.19-1.81, compared with social class I and II). Helicobacter pylori infection was more common in lower social class groups (I and II-22% infected, III-29% infected, IV and V-38% infected) and there was a significant increase in risk of infection in manual workers compared with non-manual workers after controlling for other risk factors (OR = 1.18; 95% CI: 1.03-1.34). Alcohol and coffee intake were not independent risk factors for infection and smoking was only a risk factor in those smoking >35 cigarettes a day.

CONCLUSIONS

Male gender, living with a partner and poor adult socioeconomic conditions are associated with increased risk of H. pylori infection.

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.

A case-control study of childhood environmental risk factors for the development of inflammatory bowel disease

OBJECTIVE

To clarify the relationship between childhood environment and the risk of subsequent development of Crohn's disease or ulcerative colitis.

DESIGN AND OUTCOME MEASURES

A case-control study, assessing the risk of inflammatory bowel disease in relation to a series of historical and serological markers of childhood circumstance, analysed using the maximum likelihood form of conditional logistic regression.

SETTING

District general hospital (secondary care institution).

PARTICIPANTS

Subjects with Crohn's disease (n = 139) or ulcerative colitis (n = 137) aged between 16 and 45 years, each matched for sex and age with an outpatient control.

RESULTS

Helicobacter seroprevalence was substantially reduced in Crohn's disease (OR 0.18; 95% CI, 0.06-0.52) but not in ulcerative colitis (OR 0.91; 95% CI, 0.38-2.16). In ulcerative colitis, a strong negative association with childhood appendectomy was confirmed (OR 0.05; 95% CI, 0.01-0.51). Crohn's disease was associated with childhood eczema (OR 2.81; 95% CI, 1.23-6.42) and the frequent use of a swimming pool (OR 2.90; 95% CI 1.21-6.91). There was no association between hepatitis A seroprevalence and either disease.

CONCLUSION

The findings are consistent with the hypothesis that improved childhood living conditions are associated with increased risk of Crohn's disease. The study confirms that the negative association between appendectomy and ulcerative colitis relates primarily to events in childhood. Overall, the findings strongly support the assertion that childhood environment is an important determinant of the risk of inflammatory bowel disease in later life, with quite distinct risk factors for ulcerative colitis and Crohn's disease.

Age at acquisition of Helicobacter pylori in a pediatric Canadian First Nations population

BACKGROUND

Few data exist regarding the epidemiology of Helicobacter pylori infections in aboriginal, including the First Nations (Indian) or Inuit (Eskimo) populations of North America. We have previously found 95% of the adults in Wasagamack, a First Nations community in Northeastern Manitoba, Canada, are seropositive for H. pylori. We aimed to determine the age at acquisition of H. pylori among the children of this community, and if any association existed with stool occult blood or demographic factors.

MATERIALS AND METHODS

We prospectively enrolled children resident in the Wasagamack First Nation in August 1999. A demographic questionnaire was administered. Stool was collected, frozen and batch analyzed by enzyme-linked immunosorbent assay (ELISA) for H. pylori antigen and for the presence of occult blood. Questionnaire data were analyzed and correlated with the presence or absence of H. pylori.

RESULTS

163 (47%) of the estimated 350 children aged 6 weeks to 12 years, resident in the community were enrolled. Stool was positive for H. pylori in 92 (56%). By the second year of life 67% were positive for H. pylori. The youngest to test positive was 6 weeks old. There was no correlation of a positive H. pylori status with gender, presence of pets, serum Hgb, or stool occult blood. Forty-three percent of H. pylori positive and 24% of H. pylori negative children were < 50th percentile for height (p = 0.024). Positive H. pylori status was associated with the use of indoor pail toileting (86/143) compared with outhouse toileting (6/20) (p = 0.01).

CONCLUSIONS

In a community with widespread H. pylori infection, overcrowded housing and primitive toileting, H. pylori is acquired as early as 6 weeks of age, and by the second year of life 67% of children test positive for H. pylori.

Helicobacter pylori infection in rural China: exposure to domestic animals during childhood and adulthood

Little is known about the mode of transmission of Helicobacter pylori, one of the most common human bacterial infections. Some domestic animals, including the cat, have been suggested as a reservoir of H. pylori disease, but the data have been inconsistent. This paper evaluates the role of exposure to pets and other domestic animals in the etiology of H. pylori in a rural area of China with a high prevalence of H. pylori infection. In this double-blind, population-based, cross-sectional investigation, interviews were completed with 3,288 (1994 seropositive, 1,019 seronegative, 275 indeterminate) H. pylori-infected adults enrolled in a randomized intervention trial in Linqu County, Shandong Province, China. We found no evidence to suggest that exposure to pets or other domestic animals during either childhood or adulthood was related to the prevalence of H. pylori infection. In fact, odds ratios (ORs) were reduced for subjects who had kept a cat (OR = 0.7, 95% CI = 0.4-1.0) or any animal (OR = 0.5, 95% CI = 0.3-0.9) in the house as an adult, or a cat as a child (OR = 0.7, 95% CI =0.5-1.0). ORs were also reduced for all 11 types of animal studied that subjects had kept in their courtyard as an adult. These findings suggest that zoonotic transmission, including that from domestic cats, is an unlikely route of H. pylori infection in this rural Chinese population.

Higher seroprevalence of Helicobacter pylori infection in Korean adolescent athletes compared to age- and sex-matched non-athletes

BACKGROUND

Poor living conditions, such as overcrowding and bed-sharing, are reported to be significant risk factors for Helicobacter pylori infection throughout childhood. We investigated the prevalence of H. pylori infection in Korean athletes who are obliged to live together in training camps for more than 6 months in a year.

METHODS

Blood sampling and surveying through questionnaire were performed on 440 students from a regular high school (228 boys and 212 girls) and 220 athletes (148 boys and 72 girls) of a physical education high school. We measured serum immunoglobulin G antibody (IgG Ab) to H. pylori in order to compare the prevalence of H. pylori infection between normal adolescents and athletes. In addition, we conducted a nutritional analysis and questionnaire survey for socioeconomic status in order to compare other risk factors that might influence H. pylori infection between groups.

RESULTS

The prevalence of H. pylori infection in athletes (43.2%) was higher than that in the controls (22.7%). No significant differences in the nutritional factors or socioeconomic status, such as Hollingshead index, type of house, number of siblings, and crowding index, were found between the groups. Multivariate analysis showed that crowding and the difference in school type were the significant predictors of H. pylori seropositivity after controlling for dietary and socioeconomic factors.

CONCLUSION

The seroprevalence of H. pylori infection was higher in adolescent athletes than in age- and sex-matched regular students. Further prospective study is needed to confirm the observation.

Reinfection rate following effective therapy against Helicobacter pylori infection in Japan

BACKGROUND AND AIM

In developed countries, reinfection of Helicobacter pylori (H. pylori) after eradication of the bacterium is unusual, while the reinfection rate in developing countries is variable. In this study, we determined the reinfection rate after successful H. pylori eradication in Japan, a country with a high prevalence of H. pylori infection.

METHODS

After successful eradication, 377 patients were followed up by endoscopy and urea breath test annually. In reinfected patients, H. pylori strains isolated initially and after reinfection were compared by using random amplification of polymorphic DNA fingerprinting.

RESULTS

H. pylori became positive in four of 337 patients (1.2) 1 year after eradication and in two of 133 patients (1.5) 2 years after eradication. One patient experienced an ulcer relapse 2 years after eradication therapy. Random amplification of polymorphic DNA fingerprinting of the isolated strains from four of the six patients showed two had identical strains (at 1 year) while the other two had different strains (one at 1 year and one at 2 years). When infection in the two patients reinfected with identical strains is considered a recrudescence, the true reinfection rate is < 0.8 per patient year.

CONCLUSIONS

The reinfection rate after eradication of H. pylori is low in Japan despite the country's high prevalence of H. pylori infection.

Helicobacter: a paradigm shift in peptic ulcer disease and more?

There are many diseases where the cause is unknown and this makes a specific treatment difficult. In many cases all that can be achieved is amelioration of the illness. Peptic ulcer disease was one such condition no more that 20 years ago. The management was drastic--either an operation or life-long medication in order to reduce the acid secreted by the stomach. However, the cause of this condition was discovered in 1983. Although initially sceptical, the medical fraternity now almost universally endorse Helicobacter pylori as the cause of the majority of stomach ulcers. Peptic ulcers can now be cured by antibiotics. This is a major shift in medical practice. Continued investigations on Helicobacter pylori are bringing to light other possible associations with disease as well as delineating plausible biological mechanisms for disease pathogenesis.

Helicobacter pylori seropositivity among 963 Japanese Brazilians according to sex, age, generation, and lifestyle factors

Seropositivity of anti-Helicobacter pylori antibody (HP + ) was examined among Japanese Brazilians. The study was announced through 18 Japanese community culture associations in São Paulo, Curitiba, Mogi das Cruzes, and Mirandopolis in 2001. Among 969 participants, 963 individuals aged 33 - 69 years were analyzed. The overall HP + % was 48.1% (95% confidence interval, 44.9 - 51.3%). There was no difference in HP + % between 399 males and 564 females (49.6% and 47.0%, respectively). The HP + % increased with age; 35.3% for those aged 33 - 39 years, 46.2% for those aged 40 - 49 years, 46.5% for those aged 50 - 59 years, and 56.9% for those aged 60 - 69 years, but no differences were observed among the generations (Issei, Nisei, and Sansei) for each 10-year age group. Mogi das Cruzes, a rural area, showed a higher HP + %. Length of education was inversely associated with the positivity; the odds ratio (OR) relative to those with eight years or less of schooling was 0.61 (0.42 - 0.89) for those with 12 years or more. The associations with smoking and alcohol drinking were not significant. Fruit intake was associated with the HP + %; the OR relative to everyday intake was 1.38 (1.05 - 1.83) for less frequent intake, while intake frequencies of green tea, miso soup, and pickled vegetables (tsukemono) were not. Multivariate analysis including sex, 10-year age group, residence, education, and fruit intake showed that all factors except sex were significant. This is the largest study of HP infection among Japanese Brazilians, and the results indicated a similar pattern of age-specific infection rate to that for Japanese in Japan.

Helicobacter pylori antimicrobial resistance in the United Kingdom: the effect of age, sex and socio-economic status

BACKGROUND

Helicobacter pylori antimicrobial resistance is the most common reason for eradication failure. Small studies have shown metronidazole resistance to be more prevalent in certain population groups.

AIM

To determine the resistance rates in a large cohort of patients from a single centre in the UK, and to evaluate resistance patterns over time, according to age, sex and socio-economic status.

METHODS

Consecutive patients with H. pylori-positive antral gastric biopsy samples were studied from 1994 to 1999. Susceptibility testing was performed to metronidazole, tetracycline, macrolide and amoxicillin by the modified disk diffusion

METHOD

The Jarman under-privileged area score was used as a measure of socio-economic status.

RESULTS

A total of 1064 patients were studied. Overall metronidazole resistance was 40.3%, decreasing with age (P < 0.0001, odds ratio for patients over 60 years 0.63, 95% CI: 0.48-0.80). Women were more likely to have metronidazole resistant strains (P=0.003, odds ratio 1.5, 95% CI: 1.15-1.91), but there was no association with Jarman score. Macrolide resistance was associated with metronidazole resistance (P=0.03, odds ratio 2.14, 95% CI: 1.07-4.28).

CONCLUSIONS

Metronidazole resistance in H. pylori is highly prevalent and more common in women and the young, but does not appear to be related to socio-economic status.

Helicobacter pylori infection in Swedish school children: lack of evidence of child-to-child transmission outside the family

BACKGROUND & AIMS

Helicobacter pylori infection is mainly acquired in early childhood, but the exact routes of transmission remain elusive. To distinguish between risks of intrafamilial and extraneous child-to-child transmission, we studied H. pylori seroprevalence among Swedish school children with varying family backgrounds.

METHODS

In a cross-sectional study, 695 of 858 (81%) 10-12-year-olds in 36 school classes in Stockholm donated blood and answered a questionnaire. Infection was detected by enzyme-linked immunosorbent assay and confirmed by immunoblot and urea breath test.

RESULTS

Overall, 112 (16%) children were infected. The seroprevalence was 2% among 435 children with Scandinavian parents and 55% among 144 children with origin in high prevalence areas (Middle East and Africa). Among children born in Scandinavia, the odds ratios (adjusted for gender, socioeconomic status, and family size) for being seropositive were 39.1 (95% confidence interval, 16.7-91.3) and 5.6 (1.8-17.3) when having parents born in high and medium prevalence areas, respectively, relative to children with Scandinavian parents. Importantly, the prevalence of infection among the classmates was not a risk factor for H. pylori infection.

CONCLUSION

Our data indicate that intrafamilial transmission is far more important than child-to-child transmission outside the family. The H. pylori prevalence in the parental generation may be a crucial determinant for the child's risk of contracting the infection.

Helicobacter pylori-associated iron-deficiency anemia in adolescent female athletes

OBJECTIVE

The objective was to investigate the role of Helicobacter pylori infection in iron-deficiency anemia (IDA) of pubescent athletes.

STUDY DESIGN

Blood sampling and a questionnaire survey were performed on 440 regular high school students and 220 athletes of a physical education high school. Hemoglobin, serum iron, total iron-binding capacity, ferritin, and immunoglobulin G antibody to H. pylori were measured to compare the prevalence of IDA and H. pylori infection in the groups. Nutritional analysis and a questionnaire survey for socioeconomic status were undertaken to compare and control for other risk factors that might influence IDA and H. pylori infection in the groups. In those with IDA coexistent with H. pylori infection, we also determined whether IDA can be managed by H pylori eradication.

RESULTS

The prevalence rates of IDA, H pylori infection, and H. pylori -associated IDA in female athletes were higher than in the control group. The relative risk of IDA was 2.9 (95% CI, 1.5 to 5.6) for those with H. pylori infection. Athletes who exhibited H. pylori -associated IDA showed significant increases in hemoglobin, iron, and ferritin levels after H. pylori eradication. The subjects in the control group who were treated orally with iron alone showed no significant changes.

CONCLUSION

Adolescent female athletes may have development of H. pylori -associated IDA, which can be managed by H. pylori eradication.

Familial and community environmental risk factors for Helicobacter pylori infection in children and adolescents

BACKGROUND

The aim of the study was to identify familial and community environmental risk factors associated with Helicobacter pylori infection in a pediatric population.

METHODS

Children requiring diagnostic upper endoscopy were included in the study during a 2-year period. During endoscopy, five gastric biopsies were performed for the histologic or bacteriologic diagnosis, or both, of H. pylori infection. Epidemiologic data collected by a questionnaire were analyzed using the chi-square test or Fisher test and stepwise logistic regression.

RESULTS

The authors included 436 patients (242 boys), aged 2 days to 17.9 years (median, 2.7 years). H. pylori prevalence was 7.3%. Univariate analysis found H. pylori was more common in older patients (P < 0.00001), in children who had at least one parent born in a developing country (P < 0.02) or with a low socioeconomic status (P < 0.02), and in those living in crowded conditions (P < 0.02). Children whose mother worked at home were more frequently infected than children whose mother worked outside the home (P < 0.02). Attendance at nursery or school before the age of 6 years was not associated with infection. Logistic regression showed a strong association with H. pylori only for age and number of persons at home.

CONCLUSIONS

The source of H. pylori is intrafamilial rather than from a community, such as nursery and school attended at a young age. The number of persons in the home influences the infection status of children but not by the presence of the mother in home. These data suggest that H. pylori infection transmission occurs from siblings or the father rather than from mother.

Alcohol as a gastric disinfectant? The complex relationship between alcohol consumption and current Helicobacter pylori infection

Alcoholic beverages have antimicrobial effects against Helicobacter pylori in vitro. To elucidate the relation between alcohol consumption and current infection with H. pylori in vivo, we carried out a pooled analysis of three recent studies from Southern Germany, comprising 1410 adults age 15 to 69. Detailed information on consumption of various alcoholic beverages was collected through standardized questionnaires. Helicobacter pylori infection was measured by 15C-urea breath test. Overall, prevalence of current H. pylori infection was lower among subjects who consumed alcohol (34.9%) than among nondrinkers (38.0%). The adjusted odds ratio was 0.79, with a 95% confidence interval of 0.58-1.08. Furthermore, alcohol consumption showed a strong inverse relation to the result of the 13C-urea breath test, a semiquantitative measure of the bacterial load, among infected subjects. The inverse association between alcohol consumption and H. pylori infection was not monotonic, however. Odds of infection were lowest at moderate levels of alcohol consumption and increased at higher levels of alcohol consumption, regardless of the type of alcoholic beverages consumed. These results support the hypothesis that moderate alcohol consumption may favor suppression and eventual elimination of H. pylori infection. At higher levels of alcohol consumption, the antimicrobial effects of alcoholic beverages may be opposed by adverse systemic effects of drinking, such as adverse effects on the immune defense.

Is Helicobacter pylori infection in childhood a risk factor for gastric cancer?

Helicobacter pylori infection is associated with chronic gastritis and peptic ulcer disease. Furthermore, the World Health Organization has classified this organism as a carcinogen for gastric cancer. H pylori infection is mainly acquired in childhood. Children with H pylori infection are asymptomatic except for a very small number that develop peptic ulcer disease. However, if H pylori gastritis is associated with gastric cancer, do pediatricians need to screen children for this infection and treat those who are infected? In an attempt to determine the significance of the association between H pylori and gastric cancer, we have reviewed all of the English language literature on this topic. H pylori infection seems to be associated with an increased risk of developing gastric cancer. However, only a small number of infected individuals (~1%) will develop gastric cancer. Furthermore, there are potential cofactors other than H pylori that could be equally important. The effect of the eradication of H pylori alone on the development of gastric cancer is unknown. Based on our knowledge to date, we suggest that it is not indicated to treat all children with H pylori infection because of the risk of developing gastric cancer or to institute a screening and treatment program.

Epidemiology of Helicobacter pylori infection in children: a serologic study of the Kyushu region in Japan

BACKGROUND

The prevalence of Helicobacter pylori infection in children varies as a function of socioeconomic development, with low rates in developed countries and high rates in developing countries. The prevalence of H. pylori infection in Japanese children is unknown.

METHODS

The present study examined the effect of living conditions on the prevalence of H. pylori infection in children. We determined the prevalence of H. pylori infection in healthy children of the Kyushu region in Japan and compared it with the prevalence in institutionalized children with severe neurologic illness. Serum concentrations of anti-H. pylori IgG antibody were measured by an enzyme-linked immunosorbent assay in 336 healthy children and 56 patients with severe neurologic impairment. An antibody concentration > 50 units/mL was taken as evidence of infection.

RESULTS

The prevalence of H. pylori seropositivity in healthy children increased with age (P < 0.0001) and was 29% in children 15-19 years of age. This value is slightly higher than prevalences reported in developed countries (5-15%), but is lower than in developing countries (30-60%). Seropositivity did not vary with respect to gender, water supply or location of housing. Helicobacter pylori seropositivity was more prevalent among institutionalized children aged 5-19 years than their healthy counterparts (P < 0.005).

CONCLUSIONS

The intermediate prevalence of H. pylori seropositivity in healthy children between that measured in developed and developing countries is consistent with the socioeconomic 'westernization' of Japan.

Helicobacter pylori infection among Japanese children

BACKGROUND

In Japan, there are few reports describing Helicobacter pylori infection among young children. The aim of the present study was to identify risk factors associated with H. pylori in school-aged children.

METHODS

Subjects were first-grade students of three elementary schools (n = 310) and second-grade students of a junior high school (n = 300). Personal information, such as student's medical history, parent's history, family size, sibshipsize and household pets, was collected from guardians using a questionnaire. Saliva samples and personal information were collected twice (1995 and 1996). By using the saliva samples, H. pylori IgG antibody was measured using a commercial kit. To analyze the risk factors for H. pylori infection, sex- and age-adjusted odds ratios (OR) were calculated using a multiple logistic model.

RESULTS

Among the children, factors related to Helicobacter antibody in saliva included spending a longer period of time in a nursery school or kindergarten (OR = 4.0) and a maternal history of stomach disease (OR = 2.8). Birth order (OR = 2.2), sleeping situation (OR = 2.3) and sibshipsize (OR = 1.6) were not factors that were significantly related to Helicobacter antibody in the saliva. Chewing food for the infant, family size, rooms in the household, sharing a bedroom during childhood, pets, a past history and a paternal history were not related to positivity.

CONCLUSIONS

The results indicate that transmission is person-to-person, mainly through close contact with other children and intrafamilial infection. Helicobacter pylori infection seems to occur frequently early in life, probably before 6 years of age.

An association between sudden infant death syndrome (SIDS) and Helicobacter pylori infection

BACKGROUND

Helicobacter pylori has recently been detected in the stomach and trachea of cases of sudden infant death syndrome (SIDS) and proposed as a cause of SIDS.

AIMS

To establish the incidence of H pylori in the stomach, trachea, and lung of cases of SIDS and controls.

METHODS

Stomach, trachea, and lung tissues from 32 cases of SIDS and eight control cases were examined retrospectively. Diagnosis of SIDS was based on established criteria. Controls were defined by death within 1 year of age and an identifiable cause of death. Tissues were examined histologically for the presence of bacteria. Extracted DNA from these tissues was tested for H pylori ureC and cagA sequences by nested polymerase chain reaction and amplicons detected by enzyme linked immunosorbent assay (ELISA). The cut off for each ELISA for each of the tissue types was taken as the mean optical density plus two times the standard deviation of a range of negative controls.

RESULTS

Ages of SIDS cases ranged from 2 to 28 weeks. Ages of controls ranged from 3 to 44 weeks. For the ureC gene, 25 SIDS cases were positive in one or more tissues compared with one of the controls. For the cagA gene, 25 SIDS cases were positive in one or more tissues compared with one of the controls.

CONCLUSIONS

There is a highly significant association between H pylori ureC and cagA genes in the stomach, trachea, and lung of cases of SIDS when compared with controls.

Helicobacter pylori infection in children of Texas

BACKGROUND

Acquisition of the Helicobacter pylori infection usually occurs in childhood. The prevalence of infection differs among ethnic groups and in adults is inversely related to the socioeconomic status of the individual's family during childhood. This study investigates the seroprevalence of H. pylori infection in children of different ethnic groups in relation to socioeconomic class and investigates the prevalence of acute H. pylori infection among children who have had recent onset of abdominal pain.

METHODS

Serum samples were collected from 797 children, aged 6 months to 18 years, of various socioeconomic and ethnic backgrounds, at a large urban children's hospital. H. pylori status was determined by an anti-H. pylori immunoglobulin (Ig)G enzyme-linked immunosorbent assay (ELISA) validated for pediatric use. To determine the prevalence of acute H. pylori infection, children brought to the emergency center with abdominal symptoms without diarrhea and overt signs of acute abdomen were evaluated with both serology and the 13C-urea breath test. Acute H. pylori was defined as a positive 13C-urea breath test result and negative IgG serology for H. pylori.

RESULTS

The overall seroprevalence of H. pylori was 12.2% and increased with age (e.g., 8.3% at 6-11.9 months and 17.9% at 13 years). The prevalence was inversely related to socioeconomic status (6.6%, moderate to high vs. 15%, low socioeconomic status). The difference in seroprevalence among blacks (16.8%), Hispanics (13.3%), and whites (8.3%; P < 0.01) could be accounted for by differences in socioeconomic status. Eighteen percent of children who were evaluated at the emergency center for recent-onset abdominal pain had acute H. pylori infections.

CONCLUSIONS

Socioeconomic status, not ethnic group, is the more important risk factor for acquisition of H. pylori infection during childhood. Acute H. pylori infection was a relatively common cause of recent-onset, nonsurgical abdominal pain.

Prevalence of Helicobacter pylori infection in Argentina: results of a nationwide epidemiologic study. Argentinean Hp Epidemiologic Study Group

Our aim was to assess the prevalence of Helicobacter pylori (Hp) infection in Argentina, in the general population and by age groups, and to determine the value of various epidemiologic variables as predictors of Hp infection. The study comprised 754 subjects (443 women 158.7%], 311 men [41.3%]) from both genders, consecutively recruited from health centers where patients were undergoing routine medical analyses. Average age was 32 +/- 22 years. The pediatric group included subjects < or =18 years of age (n = 261). Stratification was based primarily on climatic factors and secondarily on sanitary and demographic considerations. Hp infection status was assessed through a quick serologic test. The overall Hp infection prevalence in Argentina was 35.7 +/- 3.8%. The age was statistically significant using a multiple regression test (p < 0.01). Furthermore, the socioeconomic (p < 0.05) and educational level (0 < 0.01) in the adults and the water sources (p < 0.01) in the pediatric group were all statistically significant according the multiple regression test. The overall Hp infection prevalence in Argentina was 35.7 +/- 3.8%. Age was a predictor of Hp infection status. There is evidence of low infection prevalence in children. a higher prevalence in adolescents, and a more noticeable increase at 40 years of age. Furthermore, the socioeconomic and educational level in adults and the water sources in the pediatric group explained, in part, the occurrence of Hp infection.

Relation of Helicobacter pylori infection and angiographically demonstrated coronary artery disease

Conventional coronary risk factors explain only part of the variation in the incidence of cases of coronary heart disease. Recently H. pylori genomic material has been demonstrated in the coronary arteries of myocardial infarct. In searching for additional coronary risk factors, the potential role of H. pylori infection deserves to be investigated. To clarify if H. pylori infection is associated with an increased risk of coronary heart disease, a series of patients admitted to the Cardiac Catheterization Laboratory for coronary angiography were recruited prospectively. Cases (N = 165) were defined as those who had at least one coronary artery lesion occupying at least 50% of the luminal diameter on coronary angiography. Patients who had normal coronary angiography were selected as controls (N = 127). Demographic data, cardiovascular risk factors, and socioeconomic status were measured in both of the patients and controls. Stored serum specimens from both groups were tested for the presence of serum IgG antibody to H. pylori using enzyme-linked immunosorbent assay; 69.1% of the cases and 77.2% of the controls were seropositive for H. pylori (odds ratio 0.66, 95% CI 0.38-1.16, P = 0.12). After adjustment for age, gender, cardiovascular risk factors, and socioeconomic class, this remained nonsignificant (odds ratio 0.59, 95% CI 0.32-1.09, P = 0.09). H. pylori seropositivity was not associated with several coronary risk factors in either cases or controls. The proportion of H. pylori-positive patients was higher among the cases with triple vessel disease (77.5%) than those with double vessel disease (67.3%) and single vessel disease (65.7%); however, the differences were not statistically significant (odds ratio 0.57, 95% CI 0.23-1.4, P = 0.19). In this study no increase was found in H. pylori seropositivity in subjects with coronary artery disease. This minor association suggests that previous H. pylori infection, reflecting the early childhood environment, may not be important in determining the risk of coronary heart disease.

The proportion of upper gastrointestinal symptoms in the community associated with Helicobacter pylori, lifestyle factors, and nonsteroidal anti-inflammatory drugs. Leeds HELP Study Group

OBJECTIVE

Upper gastrointestinal disorders are common in the community, yet the determinants of these symptoms are poorly characterized. The association between upper gastrointestinal symptoms and Helicobacter pylori (H. pylori), socioeconomic status, nonsteroidal antiinflammatory drug (NSAID) use, smoking, alcohol, and coffee intake was assessed in a cross-sectional survey.

METHODS

Subjects between the ages of 40-49 yr were randomly selected from the lists of 36 primary care centers. Participants attended their local primary care center and were interviewed by a researcher using a validated dyspepsia questionnaire. H. pylori status was determined by a nonfasting 13C-urea breath test.

RESULTS

A total of 32,929 subjects were invited, and 8,407 (25%) attended and were eligible. Of these, 2,329 (28%) were H. pylori positive and 3,177 (38%) had dyspepsia. Also, 44% of H. pylori-infected participants reported dyspepsia compared with 36% of uninfected subjects [odds ratio = 1.39; 95% confidence interval (CI) 1.26-1.53]. H. pylori infection remained a significant risk factor for dyspepsia in a multiple logistic regression model (odds ratio = 1.21; 95% CI 1.09-1.34), suggesting that 5% of dyspepsia in the population is attributable to H. pylori. NSAIDs, low educational attainment, renting accommodation, absence of central heating, sharing a bed with siblings, and being married were also significantly associated with dyspepsia in this model. Smoking, but not drinking alcohol or coffee, was marginally associated with dyspepsia, but this finding was not robust. These factors were not associated with any dyspepsia subtype.

CONCLUSIONS

H. pylori is significantly associated with dyspepsia and may be responsible for 5% of upper gastrointestinal symptoms in the community.

Seroconversion and seroreversion in IgG antibodies to Helicobacter pylori: a serology based prospective cohort study

STUDY OBJECTIVES

To assess the incidence of seroconversion and seroreversion in IgG antibodies to Helicobacter pylori within a 11 year observation period using these events as markers for acquisition and loss of the infection, respectively.

DESIGN

Population based prospective cohort study.

SETTING

Northern part of Copenhagen County, Denmark.

PARTICIPANTS AND METHODS

A random sample of 2527 Danish adults were examined and blood obtained in 1983 and in 1994. Matching pairs of sera were analysed for the presence of IgG and IgM antibodies to H pylori with an in house enzyme linked immunosorbent assay. Participants who were seronegative at study entry and seropositive at follow up and had a fourfold increase in baseline IgG antibody levels were categorised as seroconverters and regarded as having acquired H pylori infection. Participants who were seropositive at study entry and had at least a fourfold decrease in baseline IgG antibody levels at follow up were assumed to have lost the infection (seroreverters).

RESULTS

The seroprevalence of H pylori infection was 24.7 (95% confidence intervals (95% CI) 23.0, 26.4) % in 1983 and 24.5 (95% CI 22.8, 26. 2) % in 1994. A total of 14 participants seroconverted within the observation period (cumulative 11 year incidence proportion: 1.0 (95% CI 0.5, 1.5) %). Having increased IgM antibody levels at study entry significantly increased the likelihood of IgG seroconversion (relative risk 6.4 (95% CI 2.1, 19.6). Seroreversion was seen in 48 participants (cumulative 11 year incidence proportion: 7.7 (95% CI 5. 6, 9.8) %).

CONCLUSIONS

Changes in H pylori infection status with time are rare in Danish adults. Few adults become infected with H pylori in Denmark.

Infection with virulent strains of Helicobacter pylori is not associated with ischaemic heart disease: evidence from a population-based case-control study of myocardial infarction

BACKGROUND

Although the majority of evidence does not support association between Helicobacter pylori infection and ischaemic heart disease, the nature of this relationship may differ when virulence of the infecting strains are examined.

METHODS AND RESULTS

The prevalence of IgG antibody evidence of infection with CagA positive stains of H. pylori was investigated in stored plasma samples from 259 cases of myocardial infarction (aged 25-70 years, 74 males) and 259 population based controls from the same area in Northern Ireland. Two-hundred and seventy (52.1%) subjects were seropositive for anti-CagA IgG. CagA seropositivity was more common in cases than in controls: 56.4 vs 47.9%, odds ratio for seropositivity in cases (95% CI) 1.41 (1.00, 1.99). Substantial attenuation of this relationship occurred on adjustment for age, sex, number of siblings, smoking and measures of socio-economic status: odds ratio (95% CI) 1.16 (0.79, 1.70). A similar pattern was seen for seropositivity for all H. pylori strains.

CONCLUSION

Infection with the more virulent strains of H. pylori, as with all strains, is not associated with myocardial infarction.

Helicobacter pylori infection occurs via close contact with infected individuals in early childhood

BACKGROUND

The manner in which Helicobacter pylori is transmitted is of fundamental importance when considering strategies for its control, yet, to date, the exact mode of transmission remains uncertain.

METHODS

The seroprevalence of H. pylori in a relatively isolated rural town in Japan (A-town) was examined to analyse the H. pylori infection route. The immunoglobulin G antibodies against H. pylori in 1684 subjects who had received public health examinations in A-town were determined with an enzyme-linked immunosorbent assay. The seroprevalence was compared in five areas according to the water source. The possibility and frequency of intrafamilial infection was analysed by comparing the seroprevalence among family members residing in the same home.

RESULTS

The seroprevalence of H. pylori did not differ significantly between the five areas examined. Seropositivity was significantly more common in the children whose mothers were seropositive (45.0%, 27/60) than in the children whose mothers were seronegative (10.0%, 2/20; odds ratio (OR) = 7.36, P = 0.0036, 95% confidence interval (CI) = 1.57-34.59). Seropositivity was significantly more common in the children whose older siblings were seropositive (55.0%, 22/40) than in the children whose older siblings were seronegative (23.5%, 20/85; OR = 3.97, P = 0.00051, 95% CI = 1.79-8.84). There was no significant relationship in seroprevalence between children and fathers, grandchildren and grandfathers, grandchildren and grandmothers, or within couples. Seropositivity was significantly more common in the adolescents who had attended a nursery school (44.4%, 20/45) than in the adolescents who had not attended a nursery school (25.6%, 109/426) (OR = 2.33, P = 0.0070, 95% CI = 1.24-4.36).

CONCLUSIONS

The acquisition of H. pylori infection occurs by close contact with infected individuals in early childhood, especially via contact with infected mothers and other infected children.

The very model of a modern etiology: a biopsychosocial view of peptic ulcer

OBJECTIVE

Research on ulcer psychosomatics has plummeted since the early 1970s, to the applause of many who argue that ulcer is simply an infectious disease. The purpose of this article is to discuss the relevance of ulcer psychogenesis in the age of Helicobacter pylori.

METHODS

A critical literature review was conducted.

RESULTS

There is a substantial and methodologically sound body of prospective studies linking stress with the onset and course of peptic ulcer. Psychosocial factors can be estimated to contribute to 30% to 65% of ulcers, whether related to nonsteroidal antiinflammatory drugs, H. pylori, or neither. The observed association between stress and ulcer is accounted for, in part, by recall bias, misreported diagnoses, and confounding by low socioeconomic status (a source of stress and of ulcer risk factors, such as H. pylori and on-the-job exertion) and by distressing medical conditions (which lead to use of nonsteroidal antiinflammatory drugs). Of the residual, true association, a substantial proportion is accounted for by mediation by health risk behaviors, such as smoking, sleeplessness, irregular meals, heavy drinking, and, again, nonsteroidal antiinflammatory drugs. The remainder results from psychophysiologic mechanisms that probably include increased duodenal acid load, the effects of hypothalamic-pituitary-adrenal axis activation on healing, altered blood flow, and impairment of gastroduodenal mucosal defenses.

CONCLUSIONS

Peptic ulcer is a valuable model for understanding the interactions among psychosocial, socioeconomic, behavioral, and infectious factors in causing disease. The discovery of H. pylori may serve, paradoxically, as a stimulus to researchers for whom the concepts of psychology and infection are not necessarily a contradiction in terms.