Helicobacter pylori prevalence in Leipzig's 1998 school entries: methodology and first results

Prevalence and risk factors for Helicobacter pylori infection in Chinese populations

BACKGROUND

The prevalence of Helicobacter pylori is higher in developing countries. The aim of this study was to investigate the prevalence and risk factors of H. pylori infection in areas with high prevalence of gastric cancer in Jiangsu Province, China.

METHODS

A prospective epidemiologic survey of H. pylori infection was accomplished in a natural population of 1457 individuals in Xiangshui and Gaoyou counties, Jiangsu Province, China. Questionnaires and laboratory tests for H. pylori infection ((13)C-urea breath test and serum IgG antibodies to H. pylori) were used and performed, respectively.

RESULT

Among 1371 subjects who completed questionnaires and H. pylori detection, 851 (62%) were H. pylori positive. The prevalence reached a peak at the age of 30-40 years (67%). There was no sex difference. The annual family income level was shown to be positively correlated with the risk of H. pylori infection. The prevalence of H. pylori infection was also associated with family size, education level, and several diet-related factors, such as the number of times cooked rice and potatoes eaten per week, and a family history of stomach diseases. Compared to nonsymptomatic individuals, people with dyspeptic symptoms (nausea, vomiting, and belching) presented a low prevalence of H. pylori infection. No association between H. pylori prevalence and smoking or drinking was found. Using multivariate logistic regression analysis, annual family income and education level were the independent predictors for H. pylori infection.

CONCLUSION

High prevalence of H. pylori infection was found in areas with a high risk of gastric cancer and was related to several risk factors. The underlying mechanisms need to be further investigated.

Hygiene could affect GERD prevalence independently: a population-based study in Tehran

OBJECTIVE

Population-based data on gastroesophageal reflux disease (GERD) in Iran are limited. Current study is going to determine the prevalence of GERD in Tehran, Iran, and its association with potential risk factors.

METHODS

In this cross-sectional study, a random clustered sample of Tehran province permanent households was selected from the latest postcodes. Data were collected by direct interview for each person aged 18-65 yr. GERD was defined as the existence of at least weekly episodes of heartburn and/or acid regurgitation during the last 6 months. All participants were asked about past and recent sanitary conditions, oral hygiene, and smoking. Odds ratios and 95% confidence intervals (CI) were calculated using multivariable analysis.

RESULTS

Interview was performed with 2,561 eligible subjects (42.3% men). Response rate was 84.8%. The prevalence of GERD was 21.2% (95% CI 18.7-23.7). According to multivariable logistic regression analyses, individuals whose drinking water was obtained from well or tank during childhood were more prone to experience GERD symptoms (OR 1.54, 95% CI 1.03-1.77 and OR 2.46, 95% CI 1.53-3.96, respectively). We also detected significant associations with increasing number of missing teeth (P value for linear trend = 0.02) and history of unpurified water consumption during past 10 yr (P < 0.001). Current smokers had a higher prevalence of reflux (OR 1.82, 95% CI 1.32-2.51).

CONCLUSION

The prevalence of GERD in our Iranian population was considerably higher than that reported from other Asian studies approaching western figures. GERD prevalence was significantly associated with the history of unpurified water consumption, poor sanitary conditions of childhood, number of missing teeth, and smoking in this population.

Association between indoor renovation activities and eczema in early childhood

BACKGROUND

Other factors besides a genetic disposition seem to play a role in the development of allergic disorders. Exposure to risk factors such as indoor air pollution is becoming increasingly interesting, especially during early childhood.

METHODS

Within an epidemiological study (LISS: Leipzig infection, allergy and airway diseases study among school starters, involving 2536 children, birth cohort 1991/92, carried out in 1997/98) the effect of indoor exposure on physician-confirmed eczema and allergic symptoms has been investigated. The exposure situation has been characterized on hand of the redecoration activities (painting, floor covering and new furniture) before birth and in the first years of life.

RESULTS

Highly exposed children showed a significant effect on allergic disorders. The lifetime prevalences without any vs. all three redecoration activities were for allergic symptoms 9.3% vs. 17.2% and for eczema 11.5% vs. 20.4%. Adjusted for confounders, the redecoration associated burden led to odds ratios of 1.8 (95% CI: 1.3-2.6) for allergic symptoms and 1.9 (95% CI: 1.4-2.7) for eczema.

CONCLUSION

Exposure emissions due to redecoration activities seem to be associated with the risk of eczema and allergic symptoms. Thus, prevention of allergic disorders should include the avoidance of such activities around birth and in the first year of life.

Helicobacter pylori determination in non-municipal drinking water and epidemiological findings

BACKGROUND

Studies conducted in Europe as well as in North and South America have tried to link Helicobacter pylori colonization with the drinking water supply, especially since H. pylori is known to survive quite well in water.

METHODS

In 2000, a cohort of 1884 grade-two children from two rural counties surrounding the city of Leipzig, Germany (77.4% of the 1991/1992 birth cohort) were tested for H. pylori colonization using the [13C]urea breath test. A parent-completed questionnaire elicited details on living conditions and lifestyle habits including questions on the children's drinking water from sources other than public water supplies, swimming in natural waters, etc. In a second independent study, samples of well water, taken from 157 private wells still used in the two counties, were being tested for the presence of H. pylori, using polymerase chain reaction (PCR) method to determine relevant target DNA fragments of H. pylori.

RESULTS

In county I, 5.7% of the children and in county II 6.6% tested H. pylori-positive. Cluster analyses of the questionnaire data in both counties pointed to 'drinking water from other than municipal sources', as the closest H. pylori-associated cluster variable. The cluster estimations were supported by odds ratio (OR) calculations with an OR=16.4 (95% confidence interval (CI) 3.1,...,88.5) for county I and OR=4.0 (95% CI 1.3,...,12.4) for county II. The PCR analyses showed H. pylori DNA fragments in 10.8% of the wells in county I and 9.2% in county II. The detection limit was set at 10 DNA copies corresponding to 125 bacteria/L, the average infestation of these wells was 931 bacteria/L.

CONCLUSION

Despite the fact that the microbiological and epidemiological data do not correspond except that both studies were conducted in the same geographical areas, the independent findings of H. pylori in well water in the same general areas where children do seem to drink water other than from the public water supply suggests that water may be an important source of H. pylori infection.

Gastric cancer

The past decade has seen many advances in knowledge about gastric cancer. Notably, tumour biology and lymphatic spread are now better understood, and treatment by surgical and medical oncologists has become more standardised. Since refrigerators have replaced other methods of food conservation, Helicobacter pylori has become a factor in the cause of gastric cancer. Cancers that arise at the oesophagogastric junction might be further examples of wealth-associated disease. To tailor treatment better, the western hemisphere needs to borrow from the East by establishing screening programmes for early diagnosis, through careful surgical resection, and through detailed analysis of tumour spread. In Europe and the USA, most patients reach treatment with cancers already at an advanced stage. For these patients, three important randomised trials are underway that evaluate combined therapy. Cytostatic drugs, especially angiogenesis inhibitors have proved disappointing; however, basic research efforts to detect familial gastric cancers and to assess minimally residual disease look more hopeful.

Five- to 7-year-old children with Helicobacter pylori infection are smaller than Helicobacter-negative children: a cross-sectional population-based study of 3,315 children

OBJECTIVE

To test whether Helicobacter pylori-positive children are smaller and weigh less than H pylori-negative children.

DESIGN

Cross-sectional population-based study.

PARTICIPANTS

In 3,315 5-to 7-year-old preschool and school children, the putative influence of H pylori infection on growth was investigated. Standing height and weight were analyzed in relation to H pylori infection. The diagnosis of H pylori infection was established by 13C-urea-breath test.

RESULTS

The prevalence of H pylori infection in boys was 7.2% (95% confidence interval, 5.9-8.9; n = 1,550) and in girls was 6.1% (95% confidence interval, 4.9-7.3; n = 1,552) H pylori-positive children were smaller than noninfected children (117.6 +/- 5.5 cm vs. 118.9 +/- 5.7 cm; P < 0.01). Although H pylori-positive boys were 2.06 cm smaller than H pylori-negative boys (117.4 +/- 5.6 cm vs. 119.5 +/- 5.7 cm; P < 0.001), the difference in girls was not significant (117.9 +/- 5.3 cm vs. 118.4 +/- 5.7 cm). When standing height was adjusted for age, the found differences were more pronounced. Differences between the infected and noninfected children with regard to body weight were not significant (22.4 +/- 4.0 kg vs. 22.1 +/- 4.0 kg), nor was there a significant difference with regard to body-mass index. However, boys with H pylori infection had a lower weight than noninfected boys (21.6 +/- 3.3 kg vs. 22.6 +/- 4.0 kg; P < 0.01), but in girls, these differences were not observed (22.2 +/- 4.0 vs. 22.8 +/- 4.6 kg, respectively). When weight was adjusted for age, H pylori -positive children also had a lower weight than H pylori -negative children because of the lower weight of boys.

CONCLUSIONS

H pylori infection is associated with growth delay, growth retardation, or both in affected children.

Helicobacter pylori in vivo diagnosis after food intake: results of simultaneous [15N]urea urine and [13C]acetate breath tests

The protocols for 13C and 15N H. pylori tests stipulate that the diagnostic agent should be taken on an empty stomach. It is presumed that food intake prior to the tests leads to less reliable test results due to a prolongation of the gastric residence time of the diagnostic agent urea. This might allow the bacteria to split a higher proportion of urea, resulting in an increased number of false positives. 12 probands received 150mg [15N]urea and 75 mg sodium [13C]acetate in 75 ml orange juice as a test drink. [15N]Urea served as an agent to diagnose gastric H. pylori colonization. The 15N tests were evaluated using a urine sample of the second hour after test start. [13C]Acetate served as a marker of the gastric emptying of water-soluble food including the urea under the influence of food intake. Breath air samples were taken to calculate the gastric emptying half life (EHL) and the apparent resorption time (RT) of the urea. The double tests were carried out four times within four weeks using identical test protocols but different standardized time periods of pretest fasting: overnight, two hours prior to test, one hour prior to test, and no fasting at all. The food intake amount was standardized. Five probands testing positive in the overnight fasting test were also found to be positive in the other test variants with more or less empty stomachs. Seven other probands testing negative after overnight fasting tested negative in the other test variants as well. It is concluded that food intake prior to the test drink does not have much of an influence on the gastric residence time of urea and so on the qualitative H. pylori test results. Due to identical behaviour of [13C]urea and [15N]urea in the stomach, this influence is believed to be independent on the labelling isotope. For survey purpose, no fasting conditions are required for the H. pylori tests.