Epidemiologic findings on serologically defined chronic atrophic gastritis strongly depend on the choice of the cutoff-value

Nationwide survey of Helicobacter pylori seropositivity and gastric atrophy in Zambia

BACKGROUND

Helicobacter pylori (H. pylori) is a common bacterial infection which predominately drives upper gastrointestinal pathology. We carried out a nationwide serological survey in response to the deficiency of robust African data on H. pylori prevalence, age of acquisition, socio-geographic determinants, and impact on gastric physiology.

MATERIALS AND METHODS

This was a cross-sectional study of archival plasma samples collected during the Zambia Population-based HIV impact Assessment (ZAMPHIA) 2016 survey. ZAMPHIA used a two-stage door-to-door stratified cluster sample approach to collect samples from adults and children from age 0 to 59 years (n = 24,266). We randomly retrieved one fifth of these samples from each of Zambia's 10 provinces and used ELISA to test for H. pylori IgG antibodies, pepsinogen 1 and 2 and gastrin-17. A pepsinogen 1:2 ratio of <3 was used to define gastric atrophy.

RESULTS

The analysis of 4050 plasma samples (30% <16 years, 53% females) revealed an overall H. pylori seroprevalence of 79%. By the age of 10 years, more than 75% of the children had H. pylori. Urban residence was associated with increased odds (OR 1.8, 95% CI 1.5-2.2, p < 0.001) and HIV infection was associated with reduced odds (OR 0.7, 95% CI 0.5-0.9, p = 0.02) of H. pylori seropositivity. Gastric atrophy was detected in 6% of H. pylori seropositive adults below 45 years of age and 9% in those between 45 and 59 years.

CONCLUSIONS

We have confirmed a high prevalence of H. pylori seropositivity in Zambia, predominantly in urban settings. The prevalence of gastric atrophy is broadly consistent with other populations around the globe, but our sample did not include adults over 60 years.

Comparison between the GastroPanel test and the serum pepsinogen assay interpreted with the ABC method-A prospective study

BACKGROUND AND AIMS

This study aimed to validate Helicobacter pylori serological and pepsinogen (PG) assays for detecting infection and gastric neoplasm.

METHODS

Individuals who underwent serum Chorus H. pylori and HBI PG assays were included from May to September 2023. The GastroPanel test was performed using the same blood sample. HBI assay findings were interpreted with the ABC method using the criteria of corpus atrophy (PG I ≤ 70 ng/mL & I/II ≤3) and advanced corpus atrophy (PG I ≤ 30 ng/mL & I/II ≤2).

RESULTS

A total of 144 H. pylori-infected and 184 non-infected Koreans were analyzed. The Chorus test (sensitivity 97.2%, specificity 89.1%) showed higher area under the curve (0.993 vs. 0.972, p = 0.003) than the GastroPanel test (sensitivity 95.8%, specificity 86.4%). Using the GastroSoft application, the incidence of gastric neoplasms was highest in the corpus atrophy group (50%), followed by the low acid-output (25.8%), H. pylori infection (11.6%), and antral atrophy (9.1%) groups. There were no gastric neoplasms in the normal and high acid output groups. Using the ABC method, the incidence of gastric neoplasms was highest in the corpus atrophy groups (23.8% in Groups C and D), followed by Group B (12.3%) and Group A (2.4%). Corpus atrophy interpreted with the GastroSoft showed poor agreement (k = 0.225) with corpus atrophy interpreted with the ABC method, whereas it showed excellent agreement (k = 0.854) with advanced corpus atrophy.

CONCLUSIONS

Although the Chorus test was more accurate than the GastroPanel test, both assays discriminated high-risk individuals by detecting atrophy or infection. There were no gastric neoplasms in the normal or high acid-output groups (GastroSoft application), and gastric neoplasm incidence was lowest in Group A (ABC method). Corpus atrophy determined by GastroSoft application is more consistent with advanced corpus atrophy determined by the ABC method than is corpus atrophy.

Clinical value of serum pepsinogen in the diagnosis and treatment of gastric diseases

Pepsinogen, secreted from the gastric mucosa, is the precursor of pepsin. It is categorized as pepsinogen 1 and pepsinogen 2 based on its immunogenicity. The pepsinogen content that can enter the blood circulation through the capillaries of the gastric mucosa is approximately 1% and remains stable all the time. The pepsinogen content in serum will change with the pathological changes of gastric mucosa. Therefore, the level of pepsinogen in serum can play a role in serologic biopsy to reflect the function and morphology of different regions of gastric mucosa and serve as an indicator of gastric disease. This study conducts relevant research on serum pepsinogen 1, pepsinogen 2, and the ratio of pepsinogen 1 to pepsinogen 2, and reviews their important value in clinical diagnosis of Helicobacter pylori infection, gastric ulcer, and even gastric carcinoma, providing ideas for other researchers.

Lifestyle and dietary factors associated with serologically detected gastric atrophy in a Caucasian population in the GISTAR study

OBJECTIVE

To identify dietary and lifestyle factors associated with decreased pepsinogen levels indicative of gastric atrophy.

METHODS

Participants aged 40 to 64 from the "Multicentric randomized study of H. pylori eradication and pepsinogen testing for prevention of gastric cancer mortality (GISTAR study)" in Latvia tested for serum pepsinogen, as well as for Helicobacter pylori infection by 13 C-urea breath test or serology were included. Data on sex, age, education, employment, diet, smoking, alcohol and proton pump inhibitor use were obtained by survey and compared for participants with and without serologically detected gastric atrophy defined as pepsinogen I/pepsinogen II ≤ 2 and pepsinogen I ≤ 30 ng/mL.

RESULTS

Of 3001 participants (median age 53, interquartile range, 11.0, 36.9% male) 52.8% had H. pylori and 7.7% had serologically detected gastric atrophy. In multivariate analysis, increasing age, consumption of alcohol, coffee, and onions were positively, while H. pylori , former smoking, pickled product and proton pump inhibitor use were inversely associated with gastric atrophy. Pepsinogen values were higher in smokers and those with H. pylori . Pepsinogen ratio was lower in those with H. pylori . When stratifying by H. pylori presence, significantly higher pepsinogen levels remained for smokers without H. pylori .

CONCLUSION

Several dietary factors and smoking were associated with serologically detected gastric atrophy. Pepsinogen levels differed by smoking and H. pylori status, which may affect the serologic detection of gastric atrophy. There seems to be a complicated interaction between multiple factors. A prospective study including atrophy determined by both serology and histology is necessary.

Associations of atrophic gastritis and proton-pump inhibitor drug use with vitamin B-12 status, and the impact of fortified foods, in older adults

BACKGROUND

Atrophic gastritis (AG) and use of proton pump inhibitors (PPIs) result in gastric acid suppression that can impair the absorption of vitamin B-12 from foods. The crystalline vitamin B-12 form, found in fortified foods, does not require gastric acid for its absorption and could thus be beneficial for older adults with hypochlorhydria, but evidence is lacking.

OBJECTIVES

To investigate associations of AG and PPI use with vitamin B-12 status, and the potential protective role of fortified foods, in older adults.

METHODS

Eligible participants (n = 3299) not using vitamin B-12 supplements were drawn from the Trinity-Ulster and Department of Agriculture cohort, a study of noninstitutionalized adults aged ≥60 y and recruited in 2008-2012. Vitamin B-12 status was measured using 4 biomarkers, and vitamin B-12 deficiency was defined as a combined indicator value < -0.5. A pepsinogen I:II ratio <3 was considered indicative of AG.

RESULTS

AG was identified in 15% of participants and associated with significantly lower serum total vitamin B-12 (P < 0.001) and plasma holotranscobalamin (holoTC; P < 0.001), and higher prevalence of vitamin B-12 deficiency (38%), compared with PPI users (21%) and controls (without AG and nonusers of PPIs; 15%; P < 0.001). PPI drugs were used (≥6 mo) by 37% of participants and were associated with lower holoTC concentrations, but only in participants taking higher doses (≥30 mg/d). Regular, compared with nonregular, consumption of fortified foods (i.e., ≥5 and 0-4 portions/wk, respectively) was associated with higher vitamin B-12 biomarkers in all participants, but inadequate to restore normal vitamin B-12 status in those with AG.

CONCLUSIONS

Older adults who have AG and/or use higher doses of PPIs are more likely to have indicators of vitamin B-12 deficiency. Fortified foods, if consumed regularly, were associated with enhanced vitamin B-12 status, but higher levels of added vitamin B-12 than currently provided could be warranted to optimize status in people with AG.

From Multiplex Serology to Serolomics-A Novel Approach to the Antibody Response against the SARS-CoV-2 Proteome

The emerging SARS-CoV-2 pandemic entails an urgent need for specific and sensitive high-throughput serological assays to assess SARS-CoV-2 epidemiology. We, therefore, aimed at developing a fluorescent-bead based SARS-CoV-2 multiplex serology assay for detection of antibody responses to the SARS-CoV-2 proteome. Proteins of the SARS-CoV-2 proteome and protein N of SARS-CoV-1 and common cold Coronaviruses (ccCoVs) were recombinantly expressed in E. coli or HEK293 cells. Assay performance was assessed in a COVID-19 case cohort (n = 48 hospitalized patients from Heidelberg) as well as n = 85 age- and sex-matched pre-pandemic controls from the ESTHER study. Assay validation included comparison with home-made immunofluorescence and commercial enzyme-linked immunosorbent (ELISA) assays. A sensitivity of 100% (95% CI: 86-100%) was achieved in COVID-19 patients 14 days post symptom onset with dual sero-positivity to SARS-CoV-2 N and the receptor-binding domain of the spike protein. The specificity obtained with this algorithm was 100% (95% CI: 96-100%). Antibody responses to ccCoVs N were abundantly high and did not correlate with those to SARS-CoV-2 N. Inclusion of additional SARS-CoV-2 proteins as well as separate assessment of immunoglobulin (Ig) classes M, A, and G allowed for explorative analyses regarding disease progression and course of antibody response. This newly developed SARS-CoV-2 multiplex serology assay achieved high sensitivity and specificity to determine SARS-CoV-2 sero-positivity. Its high throughput ability allows epidemiologic SARS-CoV-2 research in large population-based studies. Inclusion of additional pathogens into the panel as well as separate assessment of Ig isotypes will furthermore allow addressing research questions beyond SARS-CoV-2 sero-prevalence.

Chronic atrophic gastritis: an update on diagnosis

Background and aim

Atrophic gastritis is a precancerous gastric lesion, therefore its early detection is a priority in preventing gastric cancer. The aim of the present paper is to develop a narrative synthesis of the present knowledge on diagnostic methods of chronic atrophic gastritis.

Methods

A literature search was carried out on main databases: PubMed, Hinari, SpringerLink and Scopus (Elsevier) for the period 2000–2020. The searched keywords were: chronic atrophic gastritis, intestinal metaplasia and dysplasia + diagnosis. Inclusion criteria were focused on the articles about the invasive and non-invasive diagnosis of chronic atrophic gastritis and of precancerous gastric lesions, intestinal metaplasia and dysplasia; exclusion criteria were articles published before 2000 and those that did not include the proposed theme.

Results

The search returned 575 papers addressing the topic of precancerous lesions. From these, 60 articles were qualified representative for the materials published on the topic of this synthesis article, being those that met the inclusion criteria. The data emphasize the need to use upper digestive endoscopy with biopsies for the diagnosis of chronic atrophic gastritis. However serological diagnosis is available as alternative mainly recommended in follow up.

Conclusions

There are two main methodological approaches for the evaluation of chronic atrophic gastritis as a precancerous gastric lesions: invasive examination, which requires histological analysis of biopsy samples taken during upper digestive endoscopy, being the “gold standard” for diagnosis, and non-invasive serological examination using markers of gastric function.

Prevalence of atrophic gastritis in southwest China and predictive strength of serum gastrin-17: A cross-sectional study (SIGES)

A hospital-based cross-sectional study in SIGES project was conducted during 2016.5-2017.5 in West China Hospital. It was aimed to observe the prevalence of atrophic gastritis (AG) in southwest China, and assess the diagnostic strength of serum gastrin-17 (G-17) in predicting AG in Chinese population. Asymptomatic healthy controls from health check-up, cancer-free patients with unspecific upper gastrointestinal symptoms, and histologically proven gastric cancer patients were eligible, if serum pepsinogen-I (PG-I), PG-II, and G-17 were detected. AG status was classified by the accredited cutoffs of PG-I (<70 ug/L) and PG-I/II ratio (<3). Totally, healthy controls (n = 9,425), symptomatic patients (n = 671) and gastric cancer patients (n = 305) were simultaneously observed, in which the prevalence of AG in southwest China were estimated as 15.9/1,000, 28.3/1,000, and 55.7/1,000 persons, respectively. The age-specific prevalence of AG in healthy controls showed a significantly uphill trend (p for trend <0.001). Higher level of serum G-17 was significantly associated with increased risk of AG in healthy population (15-30 pmol/L, aOR = 20.67, 95% CI 9.17-46.55; >30 pmol/L, aOR = 314.41, 95% CI 166.10-595.12). Throughout the progression of stomach diseases, the diagnostic strength of serum G-17 for AG showed a downhill trend across more advanced situations. In despite of that, serum G-17 displayed a good performance in predicting AG in the entire cross-sectional population (AUC = 0.92, 95% CI 0.89-0.94; SEN = 85.5%; SPE = 93.2%; LR+ = 12.55; LR- = 0.11). Population in southwest China had intermediate prevalence of AG, while the prevalence was increased over age or disease progression. High level of serum G-17 might be a reliable non-invasive measurement to predict AG in southwest Chinese population.

Robust measurement of clinical improvement in patients with cutaneous lupus erythematosus

Objective

The severity and disease course of cutaneous lupus erythematosus (CLE) are highly variable. Consequently, outcome measures for CLE clinical improvement are heterogeneous, complicating treatment decisions and therapeutic development. This study characterises CLE outcome measures and identifies the influence of clinical improvement thresholds on strengths of associations with patient demographic and clinical factors.

Methods

In this pilot cohort study, multivariable models identified factors associated with CLE activity and skin damage improvement, defined as relative decreases in Cutaneous Lupus Activity and Severity Index (CLASI) activity (CLASI-A) and damage (CLASI-D) scores, over ranges of response thresholds.

Results

66 patients with 119 visit-pairs were included in the CLASI-A analysis. 74 patients with 177 visit-pairs were included in the CLASI-D analysis. Factors associated with CLE activity and damage improvement depended on the response threshold. Some associations were stronger at more stringent thresholds, including subacute CLE predominance with increased likelihood of CLASI-A improvement (R²=0.73; 50% reduction: OR 1.724 (95% CI 0.537 to 5.536); 75%: 5.67 (95% CI 1.56 to 20.5)) and African-American race with decreased likelihood of CLASI-D improvement (R²=0.80; 20%: 0.40 (95% CI 0.17 to 0.93); 40%: 0.25 (95% CI 0.08 to 0.82)). Other associations were stable across multiple thresholds, including older age of CLE development with increased likelihood of CLASI-A improvement (R²=0.25; 50%: 1.05 (95% CI 1.01 to 1.09]; 75%: 1.05 (95% CI 1.00 to 1.10)) and higher initial disease activity with decreased likelihood of CLASI-D improvement (R²=0.55; 20%: 0.91 (95% CI 0.84 to 0.98); 40%: 0.88 (95% CI 0.79 to 0.97)).

Conclusions

Examining a range of CLASI threshold outcomes can comprehensively characterise changes in disease course in patients with CLE. Insufficiently stringent thresholds may fail to distinguish meaningful clinical change from natural fluctuation in disease activity.

Prevalence and determinants of serological evidence of atrophic gastritis among Arab and Jewish residents of Jerusalem: a cross-sectional study

OBJECTIVE

Understanding the correlates of premalignant gastric lesions is essential for gastric cancer prevention. We examined the prevalence and correlates of serological evidence of atrophic gastritis, a premalignant gastric condition, using serum pepsinogens (PGs) in two populations with differing trends in gastric cancer incidence.

METHODS

In a cross-sectional study, using ELISA we measured serum PGI and PGII concentrations (Biohit, Finland), Helicobacter pylori serum IgG and cytotoxin-associated gene A (CagA) antigen IgG antibodies in archived sera of 692 Jews and 952 Arabs aged 25-78 years, randomly selected from Israel's population registry in age-sex and population strata. Multivariable logistic regression analyses were performed.

RESULTS

Using cut-offs of PGI <30µg/L  or PGI:PGII <3.0, the prevalence of atrophic gastritis was higher among Arab than Jewish participants: 8.8% (95% CIs 7.2% to 10.8%) vs 5.9% (95% CI 4.4% to 7.9%), increasing with age in both groups (p<0.001 for trend). Among Jewish participants, infection with H. pylori CagA phenotype was positively related to atrophic gastritis: adjusted OR (aOR) 2.16 (95% CI 0.94 to 4.97), but not to non-CagA infections aOR 1.17 (95% CI 0.53 to 2.55). The opposite was found among Arabs: aOR 0.09 (95% CI 0.03 to 0.24) for CagA positive and aOR 0.15 (95% CI 0.06 to 0.41) for Cag A negative phenotypes (p<0.001 for interaction). Women had a higher atrophic gastritis prevalence than men. Obesity and smoking were not significantly related to atrophic gastritis; physical activity tended to be inversely associated in Arabs (p=0.08 for interaction).

CONCLUSIONS

The prevalence of atrophic gastritis was higher among Arabs than Jews and was differently associated with the CagA phenotype.

Correlation between serum vitamin B12 level and peripheral neuropathy in atrophic gastritis

AIM

To explore the correlation between serum vitamin B12 level and peripheral neuropathy in patients with chronic atrophic gastritis (CAG).

METHODS

A total of 593 patients diagnosed with chronic gastritis by gastroscopy and pathological examination from September 2013 to September 2016 were selected for this study. The age of these patients ranged within 18- to 75-years-old. Blood pressure, height and weight were measured in each patient, and the body mass index value was calculated. Furthermore, gastric acid, serum gastrin, serum vitamin and serum creatinine tests were performed, and peripheral nerve conduction velocity and Helicobacter pylori (H. pylori) were detected. In addition, the type of gastritis was determined by gastroscopy. The above factors were used as independent variables to analyze chronic gastritis with peripheral neuropathy and vitamin B12 deficiency risk factors, and to analyze the relationship between vitamin B12 levels and peripheral nerve conduction velocity. In addition, in the treatment of CAG on the basis of vitamin B12, patients with peripheral neuropathy were observed.

RESULTS

Age, H. pylori infection, CAG, vitamin B9 and vitamin B12 were risk factors for the occurrence of peripheral nerve degeneration. Furthermore, CAG and H. pylori infection were risk factors for chronic gastritis associated with vitamin B12 deficiency. Serum vitamin B12 level was positively correlated with sensory nerve conduction velocity in the tibial nerve (R = 0.463). After vitamin B12 supplementation, patients with peripheral neuropathy improved.

CONCLUSION

Serum vitamin B12 levels in patients with chronic gastritis significantly decreased, and the occurrence of peripheral neuropathy had a certain correlation. CAG and H. pylori infection are risk factors for vitamin B12 deficiency and peripheral neuropathy. When treating CAG, vitamin B12 supplementation can significantly reduce peripheral nervous system lesions. Therefore, the occurrence of peripheral neuropathy associated with vitamin B12 deficiency may be considered in patients with CAG. Furthermore, the timely supplementation of vitamin B12 during the clinical treatment of CAG can reduce or prevent peripheral nervous system lesions.

Detection of gastric atrophy by circulating pepsinogens: A comparison of three assays

BACKGROUND

Circulating levels of pepsinogens have been used in high gastric cancer-risk Asian and European populations to triage endoscopic evaluation for more severe pathology. There are different analytic methods with uncertain correlations. We therefore compared diagnostic performance of three commonly used pepsinogen assays to detect histologically confirmed gastric atrophy.

METHODS

We tested plasma samples from adult patients with (n=50) and without (n=755) moderate or severe gastric corpus atrophy, as determined histologically by consensus of three expert pathologists. A single laboratory measured pepsinogens I (PgI) and II (PgII) using commercially available assays: two ELISA assays produced by Biohit (Finland) and Vector Best (Russia), and a latex agglutination assay from Eiken (Japan). Quantitative correlations were assessed by Spearman statistics. Receiver operating characteristic (ROC) curves vs histological diagnosis were calculated using both the manufacturers' and optimized cutoffs.

RESULTS

Pepsinogen levels were highly correlated among the assays (pairwise Rhos: PgI≥0.84, PgII≥0.87; all P-values<.01). Based on manufacturers' cutoffs, sensitivities, specificities and areas under the ROC curve for detecting moderate to severe histological corpus atrophy by PgI/PgII were 44%/91%/0.70, 56%/84%/0.76, and 52%/90%/0.77 for Biohit, Vector Best and Eiken, respectively. Cutoffs optimized by ROC or data mining analyses did not substantially improve test performance.

CONCLUSIONS

Commercial assays for pepsinogen have good relative agreement but are imperfect tests for clinical diagnosis of gastric atrophy.

IMPACT

Pepsinogen testing alone does not provide sufficient information for gastric cancer risk stratification. Future investigations should focus on other potential markers, in combination with pepsinogens.

Evaluation of the diagnostic value of 64 simultaneously measured autoantibodies for early detection of gastric cancer

Autoantibodies against tumor-associated antigens (TAAs) have been suggested as biomarkers for early detection of gastric cancer. However, studies that systematically assess the diagnostic performance of a large number of autoantibodies are rare. Here, we used bead-based multiplex serology to simultaneously measure autoantibody responses against 64 candidate TAAs in serum samples from 329 gastric cancer patients, 321 healthy controls and 124 participants with other diseases of the upper digestive tract. At 98% specificity, sensitivities for the 64 tested autoantibodies ranged from 0–12% in the training set and a combination of autoantibodies against five TAAs (MAGEA4 + CTAG1 + TP53 + ERBB2_C + SDCCAG8) was able to detect 32% of the gastric cancer patients at a specificity of 87% in the validation set. Sensitivities for early and late stage gastric cancers were similar, while chronic atrophic gastritis, a precursor lesion of gastric cancer, was not detectable. However, the 5-marker combination also detected 26% of the esophageal cancer patients. In conclusion, the tested autoantibodies and combinations alone did not reach sufficient sensitivity for gastric cancer screening. Nevertheless, some autoantibodies, such as anti-MAGEA4, anti-CTAG1 or anti-TP53 and their combinations could possibly contribute to the development of cancer early detection tests (not necessarily restricted to gastric cancer) when being combined with other markers.

Association of helicobacter pylori infection and chronic atrophic gastritis with risk of colonic, pancreatic and gastric cancer: A ten-year follow-up of the ESTHER cohort study

OBJECTIVES

To assess the association of H. pylori and chronic atrophic gastritis (AG) with colonic, pancreatic and gastric cancer in a population-based prospective cohort.

METHODS

Serum antibodies against H. pylori in general and specific to cytotoxin-associated gene A (CagA), as well as serum pepsinogen I and II were analyzed in 9,506 men and women, aged 50-75 years in a cohort study from Saarland, Germany. Incident cases of colonic, pancreatic and gastric cancer were ascertained by record linkage with data from the Saarland Cancer Registry.

RESULTS

During an average follow-up of 10.6 years, 108 colonic, 46 pancreatic and 27 gastric incident cancers were recorded. There was no association between H. pylori infection and colonic cancer (HR = 1.07; 95% CI 0.73-1.56) or pancreatic cancer (HR = 1.32; 0.73-2.39), regardless of either CagA seropositivity or AG status. In contrast, CagA+ infection was associated with a strongly increased risk of gastric cancer, especially non-cardia gastric cancer, and this association was particularly pronounced in the presence of AG. Compared to people without AG and without CagA+ infection, people with both risk factors had a significantly increased risk of non-cardia gastric cancer (HR = 32.4; 7.6-137.6).

CONCLUSIONS

This large cohort study did not observe an association of H. pylori infection or AG with colonic or pancreatic cancer, but underlines that the vast majority of non-cardia gastric cancers arise from AG and infection with CagA+ H. pylori strains.

Biomarkers for Helicobacter pylori infection and gastroduodenal diseases

Helicobacter pylori infection is a major cause of gastric cancer. Although identifying H. pylori infected subjects is the first approach for delineating the high-risk population for gastric cancer, the presence of H. pylori antibodies is not sufficient for gastric cancer screening. Among H. pylori infected subjects, only a minority of infected individuals develop gastric cancer. Serologic markers of H. pylori infection can serve as potential predictors for the development of gastric cancer. Serum or urinary H. pylori antibodies, cytotoxin-associated gene A antibodies, pepsinogen and microRNAs were reported to be associated with precancerous lesions or gastric cancer. In this review, we summarized the utilities and limitations of each strategy.

Prevalence of Helicobacter pylori infection and atrophic gastritis in patients with dyspeptic symptoms in Myanmar

AIM: To survey the detailed analyses for Helicobacter pylori (H. pylori) infection and gastric mucosal status in Myanmar.

METHODS: A total of 252 volunteers with dyspeptic symptoms (155 female and 97 male; mean age of 43.6 ± 14.2 years) was participated in Yangon and Mandalay. The status of H. pylori infection was determined based on 5 different tests including rapid urease test, culture, histology, immunohistochemistry and serology. Histological scores were evaluated according to the update Sydney system and the Operative Link for Gastritis Assessment system. Pepsinogen (PG) I and PG II were measured using enzyme-linked immunosorbent assays.

RESULTS: The overall prevalence of H. pylori infection was 48.0%. There was no relationship between age and infection rate. Even in young group (less than 29 years old), the H. pylori infection rate was relatively high (41.9%). The prevalence of H. pylori infection was significantly higher in Yangon than that of Mandalay. H. pylori infection was significantly associated with the presence of gastric mucosal atrophy. All 7 subjects with peptic ulcer were infected with H. pylori. Although H. pylori-positive subjects showed stronger gastritis than H. pylori-negative subjects, most cases had mild gastritis.

CONCLUSION: We revealed the prevalence of H. pylori infection in patients with dyspeptic symptoms in Myanmar. The H. pylori infection was a risk factor for peptic ulcer and stronger gastritis.

Gastric cancer: prevention, screening and early diagnosis

Gastric cancer continues to be an important healthcare problem from a global perspective. Most of the cases in the Western world are diagnosed at late stages when the treatment is largely ineffective. Helicobacter pylori (H. pylori) infection is a well-established carcinogen for gastric cancer. While lifestyle factors are important, the efficacy of interventions in their modification, as in the use of antioxidant supplements, is unconvincing. No organized screening programs can be found outside Asia (Japan and South Korea). Although several screening approaches have been proposed, including indirect atrophy detection by measuring pepsinogen in the circulation, none of them have so far been implemented, and more study data is required to justify any implementation. Mass eradication of H. pylori in high-risk areas tends to be cost-effective, but its adverse effects and resistance remain a concern. Searches for new screening biomarkers, including microRNA and cancer-autoantibody panels, as well as detection of volatile organic compounds in the breath, are in progress. Endoscopy with a proper biopsy follow-up remains the standard for early detection of cancer and related premalignant lesions. At the same time, new advanced high-resolution endoscopic technologies are showing promising results with respect to diagnosing mucosal lesions visually and targeting each biopsy. New histological risk stratifications (classifications), including OLGA and OLGIM, have recently been developed. This review addresses the current means for gastric cancer primary and secondary prevention, the available and emerging methods for screening, and new developments in endoscopic detection of early lesions of the stomach.

The Bacteroides fragilis toxin gene is prevalent in the colon mucosa of colorectal cancer patients

BACKGROUND

Enterotoxigenic Bacteroides fragilis (ETBF) produces the Bacteroides fragilis toxin, which has been associated with acute diarrheal disease, inflammatory bowel disease, and colorectal cancer (CRC). ETBF induces colon carcinogenesis in experimental models. Previous human studies have demonstrated frequent asymptomatic fecal colonization with ETBF, but no study has investigated mucosal colonization that is expected to impact colon carcinogenesis.

METHODS

We compared the presence of the bft gene in mucosal samples from colorectal neoplasia patients (cases, n = 49) to a control group undergoing outpatient colonoscopy for CRC screening or diagnostic workup (controls, n = 49). Single bacterial colonies isolated anaerobically from mucosal colon tissue were tested for the bft gene with touch-down polymerase chain reaction.

RESULTS

The mucosa of cases was significantly more often bft-positive on left (85.7%) and right (91.7%) tumor and/or paired normal tissues compared with left and right control biopsies (53.1%; P = .033 and 55.5%; P = .04, respectively). Detection of bft was concordant in most paired mucosal samples from individual cases or controls (75% cases; 67% controls). There was a trend toward increased bft positivity in mucosa from late- vs early-stage CRC patients (100% vs 72.7%, respectively; P = .093). In contrast to ETBF diarrheal disease where bft-1 detection dominates, bft-2 was the most frequent toxin isotype identified in both cases and controls, whereas multiple bft isotypes were detected more frequently in cases (P ≤ .02).

CONCLUSIONS

The bft gene is associated with colorectal neoplasia, especially in late-stage CRC. Our results suggest that mucosal bft exposure is common and may be a risk factor for developing CRC.

Virulence genes of Helicobacter pylori in the Dominican Republic

Although the incidence of gastric cancer in the Dominican Republic is not high, the disease remains a significant health problem. We first conducted a detailed analysis of Helicobacter pylori status in the Dominican Republic. In total, 158 patients (103 females and 55 males; mean age 47.1±16.2 years) were recruited. The status of H. pylori infection was determined based on four tests: rapid urease test, culture test, histological test and immunohistochemistry. The status of cagA and vacA genotypes in H. pylori was examined using PCR and gene sequencing. The overall prevalence of H. pylori infection was 58.9 %. No relationship was found between the H. pylori infection rate and the age range of 17-91 years. Even in the youngest group (patients aged <29 years), the H. pylori infection rate was 62.5 %. Peptic ulcer was found in 23 patients and gastric cancer was found in one patient. The H. pylori infection rate in patients with peptic ulcer was significantly higher than that in patients with gastritis (82.6 versus 54.5 %, P<0.01). The cagA-positive/vacA s1m1 genotype was the most prevalent (43/64, 67.2 %). Compared with H. pylori-negative patients, H. pylori-positive patients showed more severe gastritis. Furthermore, the presence of cagA was related to the presence of more severe gastritis. All CagA-positive strains had Western-type CagA. In conclusion, we found that H. pylori infection is a risk factor for peptic ulcer in the Dominican Republic. Patients with cagA-positive H. pylori could be at higher risk for severe inflammation and atrophy.

Polymorphisms in genes coding for HSP-70 are associated with gastric cancer and duodenal ulcer in a population at high risk of gastric cancer in Costa Rica

BACKGROUND AND AIMS

Costa Rica has among the highest incidence and mortality rates for gastric cancer worldwide. The reasons for this are largely unknown. Polymorphisms of inflammatory response genes including genes encoding heat shock proteins (HSP) have been shown to be associated with the risk of gastric cancer in some populations. This study addresses the possible association between the HSP70-2 +1267 and HSP70-Hom +2437 polymorphisms and the risk of developing gastric cancer in a high-risk population in Costa Rica.

METHODS

DNA from 39 individuals diagnosed with gastric cancer, 79 healthy controls, 55 individuals with chronic gastritis and 52 individuals with duodenal ulcer was genotyped for the polymorphisms HSP70-2 +1267 and HSP70-Hom +2437 by RFLP. Logistic regression analysis was used to determine possible associations with the diagnoses and lineal regression analysis to determine associations with blood pepsinogen (PGs) levels as measured by serology.

RESULTS

The GA genotype of HSP70-2 was associated with increased risk of gastric cancer (OR = 3.42; 95% CI = 1.27-9.21; p = 0.015) and duodenal ulcer (OR = 2.57; 95% CI = 1.03-6.36; p = 0.042) as compared to the GG genotype. Persons with C carrier genotypes of HSP70-Hom were significantly less susceptible to gastric cancer than those with the TT genotype (OR = 0.29; 95% CI = 0.09-0.87; p = 0.027). The C carrier genotype was associated with lower PGI concentrations but none of the polymorphisms were associated with PGI/PGII.

CONCLUSIONS

Polymorphisms of HSP70 genes are associated with the development of gastric cancer and duodenal ulcers in a population at high risk for gastric cancer in Costa Rica.

Eradication of gastric cancer is now both possible and practical

In 1994, Helicobacter pylori was declared a human carcinogen. Evidence has now accumulated to show that at least 95% of gastric cancers are etiologically related to H. pylori. An extensive literature regarding atrophic gastritis and its effects on acid secretion, gastric microflora, and its tight association with gastric cancer has been rediscovered, confirmed, and expanded. Methods to stratify cancer risk based on endoscopic and histologic findings or serologic testing of pepsinogen levels and H. pylori testing have been developed producing practical primary and secondary gastric cancer prevention strategies. H. pylori eradication halts progressive mucosal damage. Cure of the infection in those with non-atrophic gastritis will essentially prevent subsequent development of gastric cancer. For all, the age-related progression in cancer risk is halted and likely reduced as eradication reduces or eliminates mucosal inflammation and reverses or reduces H. pylori-associated molecular events such aberrant activation-induced cytidine deaminase expression, double strand DNA breaks, impaired DNA mismatch repair and aberrant DNA methylation. Those who have developed atrophic gastritis/gastric atrophy however retain some residual risk for gastric cancer which is proportional to the extent and severity of atrophic gastritis. Primary and secondary cancer prevention starts with H. pylori eradication and cancer risk stratification to identify those at higher risk who should also be considered for secondary cancer prevention programs. Japan has embarked on population-wide H. pylori eradication coupled with surveillance targeted to those with significant remaining risk. We anticipate that countries with high gastric cancer burdens will follow their lead. We provide specific recommendations on instituting practical primary and secondary gastric cancer prevention programs as well identifying research needed to make elimination of gastric cancer both efficient and cost effective.

Seroprevalence of Helicobacter pylori infection and gastric mucosal atrophy in Bhutan, a country with a high prevalence of gastric cancer

Gastric cancer is the second leading cause of cancer-related mortality in the world. Recently, serum Helicobacter pylori antibodies and pepsinogen (PG) have been used for gastric cancer screening. The incidence of gastric cancer in Bhutan is reported to be quite high compared with that in neighbouring countries. In this study, 381 subjects from three areas of Bhutan were assessed for gastric mucosal atrophy and serological parameters. Anti-H. pylori IgG, PG I, PG II and cytotoxin-associated gene A (CagA) antibodies were measured using ELISA. Subjects were classified into four groups according to H. pylori and PG seropositivity: Group A (H. pylori-negative/PG-negative), Group B (H. pylori-positive/PG-negative), Group C (H. pylori-positive/PG-positive) and Group D (H. pylori-negative/PG-positive). The prevalence of H. pylori in the 381 subjects was 71.1% (271/381), with high infection rates found in rural areas. The PG I/II ratio was significantly inversely correlated with the atrophy score in the antrum and the corpus (P<0.001). Multivariate analysis showed that the PG status was significantly associated with the presence of atrophy in the corpus. The prevalence of the PG-positive status was significantly higher among H. pylori-positive subjects than among H. pylori-negative subjects (P<0.001). Based on the ABC method, Group B was the most dominant, followed by Group A, Group C and Group D. The high incidence of gastric cancer in Bhutan can be attributed to the high prevalence of H. pylori infection and gastric mucosal atrophy.

Gastric parietal cell antibodies, Helicobacter pylori infection, and chronic atrophic gastritis: evidence from a large population-based study in Germany

BACKGROUND

Striking similarities between autoimmune gastritis and Helicobacter Pylori (H. pylori)-associated gastritis have suggested a potential link between these two pathologic conditions in the progression of chronic atrophic gastritis (CAG); however, evidence has remained conflicting.

METHODS

Serum pepsinogen I and II, and antibodies against H. pylori in general, the cytotoxin-associated gene A protein (CagA) and parietal cells were measured by ELISA in 9,684 subjects aged 50 to 74 years. Antigastric parietal cell antibody (APCA) prevalence was examined in the overall population and according to sex, age, and H. pylori serostatus. The association between APCA prevalence and CAG was assessed by logistic regression, overall and according to H. pylori status, controlling for potential confounding factors.

RESULTS

Overall APCA prevalence was 19.5%. APCA prevalence was strongly associated with CAG, and the association was increasing with increasing severity of CAG. Furthermore, the association between APCA and CAG was even stronger among H. pylori-negative subjects [odds ratio (OR) = 11.3; 95% confidence interval (CI): 7.5-17.1)] than among H. pylori-positive subjects (OR = 2.6; 95% CI: 2.1-3.3).

CONCLUSIONS

APCA may play a role on the development of gastric atrophy, irrespective of H. pylori infection.

IMPACT

Assessment of APCA might be a useful complement to established markers (such as pepsinogens and H. pylori antibodies) in screening for CAG.

Serum pepsinogen II is a better diagnostic marker in gastric cancer

AIM

To investigate screening makers for gastric cancer, we assessed the association between gastric cancer and serum pepsinogens (PGs).

METHODS

The subjects comprised 450 patients with gastric cancer, 111 individuals with gastric atrophy, and 961 healthy controls. Serum anti-Helicobacter pylori (H. pylori) immunoglobulin G (IgG), PGI and PG II were detected by enzyme-linked immunosorbent assay. Gastric atrophy and gastric cancer were diagnosed by endoscopy and histopathological examinations. Odds ratios and 95%CIs were calculated using multivariate logistic regression.

RESULTS

Rates of H. pylori infection remained high in Northeastern China. Rates of H. pylori IgG positivity were greater in the gastric cancer and gastric atrophy groups compared to the control group (69.1% and 75.7% vs 49.7%, P < 0.001). Higher levels of PG II (15.9 μg/L and 13.9 μg/L vs 11.5 μg/L, P < 0.001) and lower PGI/PG II ratio (5.4 and 4.6 vs 8.4, P < 0.001) were found in patients with gastric cancer or gastric atrophy compared to healthy controls, whereas no correlation was found between the plasma PGI concentration and risk of gastric cancer (P = 0.537). In addition, multivariate logistic analysis indicated that H. pylori infection and atrophic gastritis were independent risk factors for gastric cancer. Lower plasma PGI/PG II ratio was associated with higher risks of atrophy and gastric cancer. Furthermore, plasma PG II level significantly correlated with H. pylori-infected gastric cancer.

CONCLUSION

Serum PG II concentration and PGI/PG II ratio are potential biomarkers for H. pylori-infected gastric disease. PG II is independently associated with risk of gastric cancer.

Prevalence of Helicobacter pylori infection and atrophic gastritis in Latvia

OBJECTIVES

Helicobacter pylori infection and atrophic gastritis are related to an increased risk for gastric cancer. There is a decrease in global H. pylori prevalence. We analyzed the prevalence of H. pylori infection in Latvia by the plasma IgG test and the presence of atrophy by means of pepsinogen testing.

METHODS

This subanalysis was carried out on a randomly selected cross-sectional sample of a general population of adults to access cardiovascular risk factors. Plasma samples were screened for H. pylori IgG (cutoff value 24 U/ml), and pepsinogens (Pg) I and II. Pg cutoff values of PgI/PgII ≤ 3 and PgI ≤ 70 ng/ml were used to assess the prevalence of atrophy of any grade and PgI/PgII ≤ 2 and PgI ≤ 30 ng/ml for advanced atrophy.

RESULTS

Altogether, 3564 serum samples were available for the study (2346 women, 1218 men; median age 54 years). Of the tested individuals, 79.21% were H. pylori positive, with no difference between sexes. The prevalence increased with age (P<0.001). Atrophy of any grade was identified in 1444 individuals (40.52%) and advanced atrophy in 475 individuals (13.33%). Linear association with age was present in both response types (P<0.001). The prevalence of atrophy of any grade was higher in women (41.73%) than in men (38.18%; P=0.04); this difference was lost for advanced atrophy (women 13.98%, men 12.07%; P=0.1).

CONCLUSION

The prevalence of H. pylori infection or atrophy remains high in Latvia. Determining the right cutoff value is critically important for pepsinogen-based atrophy detection in Europe in order to objectively stratify gastric cancer risk.

Helicobacter pylori: clinical management

PURPOSE OF REVIEW

Progress continues in our understanding of the role of Helicobacter pylori infection in gastroduodenal as well as extragastric disorders. This review gives an overview on selected areas of the H. pylori infection and their clinical implications.

RECENT FINDINGS

Indications for therapy have been extended and now include idiopathic thrombocytopenic purpura, iron deficiency anemia, and vitamin B12 deficiency. New data are presented on the role of H. pylori in neurodegenerative disorders and in the metabolic syndrome. H. pylori is associated with a (small) increase in the risk for colorectal adenoma and colon cancer. The biggest challenge is the selection of new therapies and treatment strategies because of the increasing failure of standard triple therapies. The best option in high clarithromycin resistance areas is bismuth-based quadruple therapy. Probiotic bacteria and yeasts reduce adverse effects of standard H. pylori eradication regimens. In gastric cancer prevention, screening programs based on the serological detection of preneoplastic conditions may prove useful.

SUMMARY

New algorithms for preventing H. pylori-induced disease and eradicating the organism should be individualized.

Helicobacter pylori infection is strongly associated with gastric and duodenal ulcers in a large prospective study

BACKGROUND & AIMS

Infection with Helicobacter pylori (H pylori) is a risk factor for peptic ulcer disease (PUD), but there are limited longitudinal data on the associations between infection and incident gastric or duodenal ulcers.

METHODS

Information on potential risk factors, lifetime history of PUD, and serologic measurements of H pylori infection were obtained from a German cohort of 9953 adults, 50 to 74 years old at baseline (2000-2002). The incidence of ulcers was determined by questionnaires sent to study participants and general practitioners 2 and 5 years later, and was validated by medical records.

RESULTS

A lifetime history of PUD was reported by 1030 participants, and during the follow-up period 48 had a first gastric and 22 had a first duodenal ulcer. Infection with H pylori strains that express cytotoxin-associated gene A (cagA) was significantly associated with a lifetime history of PUD (odds ratio, 1.75; 95% confidence interval [CI], 1.50-2.04). Based on longitudinal analyses with physician-validated end points, the adjusted hazard ratios for incident gastric and duodenal ulcer disease were 2.9 (95% CI, 1.5-5.5) and 18.4 (95% CI, 4.2-79.9), respectively, among patients infected with cagA-positive strains of H pylori.

CONCLUSIONS

In cross-sectional analysis, infection with cagA-positive strains of H pylori was associated with a 1.75-fold increased risk of peptic ulcer disease. Longitudinal analyses revealed an 18.4- and 2.9-fold increased risk for duodenal ulcer and gastric ulcer, respectively. The proportion of PUD that is attributable to H pylori infection might be larger than previously believed.

Helicobacter pylori infection and colorectal cancer risk: evidence from a large population-based case-control study in Germany

Evidence concerning the role of Helicobacter pylori infection in the development of colorectal cancer remains controversial. The authors assessed the association of H. pylori seroprevalence with risk of colorectal cancer in a large population-based case-control study from Germany in 2003-2007. Serum antibodies to H. pylori in general and the cytotoxin-associated gene A protein (CagA) were measured in 1,712 incident colorectal cancer cases and 1,669 controls. The association between H. pylori seroprevalence and colorectal cancer risk was estimated by logistic regression, with adjustment for potential confounders and stratification by age group, sex, anatomic subsites, and cancer stage. Overall, H. pylori seroprevalence was higher in cases (46.1%) than in controls (40.1%), resulting in an age- and sex-adjusted odds ratio of 1.30 (95% confidence interval (CI): 1.14, 1.50). Adjustment for established colorectal cancer risk factors decreased the odds ratio to 1.26 (95% CI: 1.09, 1.47), with a further reduction to 1.18 (95% CI: 1.01, 1.38) after additional adjustment for previous colorectal endoscopy. Stratified analyses showed risk elevation to be essentially confined to left-sided colorectal cancer, with an odds ratio of 1.22 (95% CI: 1.02, 1.45), suggesting that H. pylori infection may be associated with a small yet relevant risk increase in the left colorectum.

Serological assessment of gastric mucosal atrophy in gastric cancer

Background

Non-invasive tools for gastric cancer screening and diagnosis are lacking. Serological testing with the detection of pepsinogen 1 (PG1), pepsinogen 2 (PG2) and gastrin 17 (G17) offers the possibility to detect preneoplastic gastric mucosal conditions. Aim of this study was to assess the performance of these serological tests in the presence of gastric neoplasia.

Methods

Histological and serological samples of 118 patients with gastric cancer have been assessed for tumor specific characteristics (Laurén type, localisation), degree of mucosal abnormalities (intestinal metaplasia, atrophy) and serological parameters (PG1, PG2, PG1/2-ratio, G17, H. pylori IgG, CagA status). Association of the general factors to the different serological values have been statistically analyzed.

Results

Patients with intestinal type gastric cancer had lower PG1 levels and a lower PG1/2-ratio compared to those with diffuse type cancer (p = 0.003). The serum levels of PG2 itself and G17 were not significantly altered. H. pylori infection in general had no influence on the levels of PG1, PG2 and G17 in the serum of gastric cancer patients. There was a trend towards lower PG1 levels in case of positive CagA-status (p = 0.058). The degree of both intestinal metaplasia and atrophy correlated inversely with serum levels for PG1 and the PG1/2-ratio (p < 0.01). Laurén-specific analysis revealed that this is only true for intestinal type tumors. Univariate ANOVA revealed atrophy and CagA-status as the only independent factors for low PG1 and a low PG1/2-ratio.

Conclusions

Glandular atrophy and a positive CagA status are determinant factors for decreased pepsinogen 1 levels in the serum of patients with gastric cancer. The serological assessment of gastric atrophy by analysis of serum pepsinogen is only adequate for patients with intestinal type cancer.

Accuracy and cut-off values of pepsinogens I, II and gastrin 17 for diagnosis of gastric fundic atrophy: influence of gastritis

Background

To establish optimal cutoff values for serologic diagnosis of fundic atrophy in a high-risk area for oesophageal squamous cell carcinoma and gastric cancer with high prevalence of Helicobacter pylori (H. pylori) in Northern Iran, we performed an endoscopy-room-based validation study.

Methods

We measured serum pepsinogens I (PGI) and II (PGII), gastrin 17 (G-17), and antibodies against whole H. pylori, or cytotoxin-associated gene A (CagA) antigen among 309 consecutive patients in two major endoscopy clinics in northeastern Iran. Updated Sydney System was used as histology gold standard. Areas under curves (AUCs), optimal cutoff and predictive values were calculated for serum biomarkers against the histology.

Results

309 persons were recruited (mean age: 63.5 years old, 59.5% female). 84.5% were H. pylori positive and 77.5% were CagA positive. 21 fundic atrophy and 101 nonatrophic pangastritis were diagnosed. The best cutoff values in fundic atrophy assessment were calculated at PGI<56 µg/l (sensitivity: 61.9%, specificity: 94.8%) and PGI/PGII ratio<5 (sensitivity: 75.0%, specificity: 91.0%). A serum G-17<2.6 pmol/l or G-17>40 pmol/l was 81% sensitive and 73.3% specific for diagnosing fundic atrophy. At cutoff concentration of 11.8 µg/l, PGII showed 84.2% sensitivity and 45.4% specificity to distinguish nonatrophic pangastritis. Exclusion of nonatrophic pangastritis enhanced diagnostic ability of PGI/PGII ratio (from AUC = 0.66 to 0.90) but did not affect AUC of PGI. After restricting study samples to those with PGII<11.8, the sensitivity of using PGI<56 to define fundic atrophy increased to 83.3% (95%CI 51.6–97.9) and its specificity decreased to 88.8% (95%CI 80.8–94.3).

Conclusions

Among endoscopy clinic patients, PGII is a sensitive marker for extension of nonatrophic gastritis toward the corpus. PGI is a stable biomarker in assessment of fundic atrophy and has similar accuracy to PGI/PGII ratio among populations with prevalent nonatrophic pangastritis.

Dopamine-related genes and spontaneous smoking cessation in ever-heavy smokers

Several studies have provided evidence for associations of polymorphisms located in and near dopamine-related genes and nicotine dependence and other smoking-related phenotypes, including pharmacogenetic interactions.

AIM

The purpose of the present work was to examine the association of SNPs in the DOPA decarboxylase (DDC), dopamine receptor D2 (DRD2) and dopamine transporter (SLC6A3) genes with smoking cessation in a large retrospective study featuring approximately 900 cessation events.

MATERIALS & METHODS

Data originated from the enrollment questionnaire of the epidemiological ESTHER study of community-dwelling adults aged 50-74 years, conducted in the German state of Saarland between July 2000 and December 2002. Restricting the analyses to subjects who reported to have regularly smoked > 20 cigarettes per day at some point in their life, we used survival analysis methods to model the time from initiation of regular smoking to cessation (defined as quitting with abstinence lasting until enrollment) and its relation with eight polymorphisms in the aforementioned genes (five in DDC, two in DRD2 and one in SLC6A3) in 1446 participants.

RESULTS

Neither individual variants nor DDC haplotypes were associated with the probability of overcoming nicotine dependence in this cohort.

CONCLUSION

The repeated suggestion of associations between the variants examined and nicotine dependence in previous reports seems to contrast the negative results in the present study. This would appear consistent with the hypothesis that the establishment of regular heavy smoking might abolish associations between genetic determinants of nicotine dependence and nicotine dependence-related phenotypes, in particular the probability of successful smoking cessation.

Polymorphisms in MUC1, MUC2, MUC5B and MUC6 genes are not associated with the risk of chronic atrophic gastritis

Mucins represent major components of the mucous layer in the stomach, protecting the underlying epithelium from acid, mechanical trauma, proteases and pathogenic bacteria. Previous studies have shown an association of neoplastic transformation in the stomach with aberrant mucin levels, suggesting a potential role of genetic variation in mucin genes in the development of gastric cancer (GC). We assessed the association of genetic variation in candidate single nucleotide polymorphisms (SNPs) in mucin genes with the risk of chronic atrophic gastritis (CAG), a well-established precursor of GC in the German population-based ESTHER study. We genotyped MUC1 T31T, MUC2 L58P, MUC2 V116M, MUC5B E34G, MUC5B R51W, MUC5B rs2014486 (intronic) and MUC6 V619M for 533 serologically defined CAG cases and 1054 age- and sex-matched controls. None of the analysed SNPs was associated with CAG. However, large studies are needed to disclose or exclude potential weak associations of these SNPs with CAG risk.

Plasma pepsinogens, antibodies against Helicobacter pylori, and risk of gastric cancer in the Shanghai Women's Health Study Cohort

Background:

Circulating pepsinogens can indicate atrophic gastritis, a precursor of gastric cancer. We tested the association between gastric cancer and plasma pepsinogens and antibodies against Helicobacter pylori in a case–control study nested in a prospective cohort.

Methods:

We selected 141 gastric cancer cases and 282 incidence-density sampled controls. Plasma concentrations of pepsinogens 1 and 2 were measured using ELISA kits, and anti-H. pylori antibodies were measured using a kit specific to Chinese strains. Associations were estimated using conditional logistic regression models adjusted for potential confounders.

Results:

Gastric cancer subjects were more likely to be anti-H. pylori positive than controls, 97 vs 92%. A plasma pepsinogen 1 (PG1) concentration <50 ng ml^–1 (15% of cases) was associated with a significantly increased risk of gastric cancer (OR 4.23; (95% CI: 1.86–9.63), whereas a plasma pepsinogen 2 (PG2) concentration >6.6 ng ml^–1 (75% of cases) was also associated with a significantly increased risk of gastric cancer (OR 3.62; (95% CI: 1.85–7.09). We also found that the PG1 : 2 ratio had a nearly linear association with gastric cancer risk.

Conclusion:

Lower plasma PG1 : 2 ratios are associated with a higher risk of gastric cancer. Furthermore, it appears that circulating pepsinogens 1 and 2 may be independently associated with the risk of gastric cancer.

Grb2-associated binder 1 (Gab1) genetic polymorphism, Helicobacter pylori infection, and chronic atrophic gastritis among older adults from Germany

Grb2-associated binder 1 (Gab1) plays an important role in the regulation of cell growth and transformation. A single nucleotide polymorphism (SNP) (rs3805246) in the Gab1 gene has been suggested to be related to the risk of Helicobacter pylori infection and chronic atrophic gastritis (CAG) in a study from Japan. We aimed to assess the associations in a population-based study from Germany. In the baseline examination of ESTHER, a population-based study conducted in Saarland, serum pepsinogen I and II and H. pylori serostatus were measured by ELISA. The Gab1 SNP (rs3805246) was genotyped in 351 serologically defined CAG cases and 351 age- and sex-matched non-CAG controls. A nonsignificant association was observed between the Gab1 SNP and CAG, with an adjusted odds ratio of 1.15 (0.85-1.55) for AA/AG carriers compared to GG carriers. The magnitude of the association did not change when the analysis was restricted to H. pylori seropositive subjects. Furthermore, no significant relation was found between the SNP and H. pylori seropositivity among non-CAG controls. We could not confirm a major association between Gab1 SNP (rs3805246) and the predisposition to H. pylori infection and CAG in this study population from Germany. Further studies with larger sample size are needed to clarify a potential modest effect of Gab1 genetic polymorphisms.

Increased exposure to bacterial antigen RpL7/L12 in early stage colorectal cancer patients

BACKGROUND

Cancer 2010. (c) 2010 American Cancer Society. : Intestinal bacteria have long been implicated in colorectal cancer pathology, and many reports point to a close linkage between Streptococcus bovis biotype I (recently renamed Streptococcus gallolyticus) infections and tumors of the human colon. This work aims to investigate the humoral immune response to this bacterium during different stages of colorectal cancer.

METHODS

The presence of serum antibodies against S. bovis antigen RpL7/L12, previously assigned as a potential diagnostic antigen, was evaluated in Dutch (n = 209) and American (n = 112) populations using a newly developed enzyme-linked immunosorbent assay.

RESULTS

The analyses consistently showed that an immune response against this bacterial antigen was increased in polyp patients and stage I/II colorectal cancer patients as compared with asymptomatic individuals. This was not paralleled by increased antibody production to endotoxin, an intrinsic cell wall component of the majority of intestinal bacteria, which implies that the humoral immune response against RpL7/L12 is not a general phenomenon induced by the loss of colonic barrier function. Notably, increased anti-RpL7/L12 levels were not or were only mildly detected in late stage colorectal cancer patients having lymph node or distant metastasis.

CONCLUSIONS

Cancer 2010. (c) 2010 American Cancer Society. : These findings are indicative of an increased exposure to antigen RpL7/L12 during early stages of colon carcinogenesis and suggest that intestinal bacteria such as S. bovis constitute a risk factor for the progression of premalignant lesions into early stage carcinomas. Clearly, the current findings emphasize the necessity for further studies on the possible etiologic relationship between intestinal bacteria and human colorectal cancer.

Body mass index, chronic atrophic gastritis and heartburn: a population-based study among 8936 older adults from Germany

BACKGROUND

Obesity and overweight have been positively related to gastro-oesophageal reflux disease (GERD). It has been suggested that this relationship is as a consequence of an increased gastric acid reflux, which is caused by an enhanced intra-abdominal pressure.

AIM

To assess potential interaction of the association between body mass index (BMI) and GERD by chronic atrophic gastritis, which goes along with decreased acid production.

METHODS

In the baseline examination of ESTHER, a study conducted in 9953 older adults in Saarland, information on frequency of heartburn, potential risk factors and medical history was obtained by self-administered standardized questionnaire. Serological measurements of pepsinogen I and II were taken for definition of chronic atrophic gastritis.

RESULTS

In total, 2565 (28.7%) of the included subjects experienced heartburn within the previous 4 weeks. A pronounced dose-response relationship was observed between BMI and heartburn occurrence (P < 0.001) among people without chronic atrophic gastritis, but not among people with chronic atrophic gastritis (P-value for interaction = 0.018). Obese/overweight people with chronic atrophic gastritis had a much lower risk of heartburn compared with obese/overweight people without chronic atrophic gastritis (OR = 0.31, 95% CI = 0.24-0.40).

CONCLUSION

Our results are consistent with the hypothesis that BMI is related positively to GERD symptoms by its impact on acid reflux.

Incidence of chronic atrophic gastritis: systematic review and meta-analysis of follow-up studies

Chronic atrophic gastritis (CAG) is an important precursor lesion of intestinal gastric cancer. As it is typically asymptomatic, epidemiological data on the incidence of CAG are sparse. We aimed to provide an overview of published data on CAG incidence (overall and according to risk factors) from follow-up studies. Articles with information on incidence of CAG published in English until 26th of July 2009 were identified through a systematic MEDLINE and EMBASE search. Data extracted include study characteristics and key findings regarding the incidence of CAG. A meta-analysis was performed on the association between Helicobacter pylori infection and CAG incidence. Overall, data on CAG incidence were available from 14 studies, in 7 studies incidence could be estimated according to H. pylori infection. Most studies were conducted in symptomatic or high risk populations and the maximum number of incident cases was 284. Incidence estimates ranged from 0 to 11% per year and were consistently below 1% in patients not infected with H. pylori. The highest incidence was observed in a special study conducted on ulcer patients treated by proximal gastric vagotomy. Rate ratios for the association between H. pylori infection and CAG incidence ranged from 2.4 to 7.6 with a summary estimate of 5.0 (95% confidence interval: 3.1-8.3). Incidence of CAG is very low in the absence of H. pylori infection. There is a need for more population-based studies to provide comparable estimates of incidence and the impact of risk factors in the development of CAG.

Incidence and risk factors for the development of chronic atrophic gastritis: five year follow-up of a population-based cohort study

Chronic atrophic gastritis (CAG) is a well-established precursor of intestinal gastric cancer. However, data on incidence of CAG are rare, especially from population-based studies. The aim of this analysis was to estimate the incidence of CAG in a large population-based study among older adults from Germany and to identify major risk factors associated with its development. In the baseline and 5-year follow-up examinations of the ESTHER study, serological measurements of pepsinogen (PG) I and II and Helicobacter pylori antibodies were performed in 5,229 women and men, aged 50-74 years at baseline. Information on additional potential risk factors was obtained by questionnaire. CAG was defined by PGI < 70 ng/mL and PGI/PGII < 3. In total, there were 58 (1.1%) incident CAG cases. CAG incidence increased with increasing age from 0.5% in age group 50-54 years to 2.1% in age group 70-74 years. Seropositivity with H. pylori was strongly associated with CAG incidence, with adjusted odds ratios of 5.0 [95% confidence interval (CI): 1.6-15.8] and 11.3 (95% CI: 4.2-30.0) for participants with cytotoxin associated gene A (cagA) negative and cagA positive H. pylori infection at both baseline and follow-up compared to those without H. pylori infection, respectively. Gender, education, smoking, alcohol consumption and family history of gastric cancer were not significantly associated with CAG incidence. Incidence of CAG is rather low in the German population. Older age and infection with H. pylori are key risk factors for the development of CAG.

Low-to-moderate alcohol consumption and smoking cessation rates: retrospective analysis of 4576 elderly ever-smokers

BACKGROUND

Smoking and alcohol consumption are two major risk factors for manifold morbidity and mortality outcomes and are highly correlated with each other. No conclusion has been reached concerning whether cigarette smokers drinking alcohol have more difficulties with smoking cessation. We aimed to elucidate the association of concurrent alcohol consumption with the probability of smoking cessation in non-clinical populations.

METHODS

Retrospective analysis in 4576 ever-smoking participants of the baseline survey of ESTHER, a population-based study in Germany, aged 50-74 at enrollment in general practitioner offices. Life-course histories of alcohol consumption were obtained from questionnaire items covering exposure intensities at ages 20, 30, 40, 50 and at the time of enrollment. Extended Cox regression modelling allowing for the time-varying nature of alcohol consumption was employed to model the time from smoking initiation to smoking cessation.

RESULTS

Using alcohol abstainers as the reference group and controlling for potential confounders, relative cessation rates (95% CI) increased to 1.17 (1.02, 1.34), 1.36 (1.20, 1.55), 1.45 (1.27, 1.66) and 1.32 (1.13, 1.53) with concurrent consumption of 1-39, 40-99, 100-199 and 200+g alcohol/week. This pattern persisted in extensive sensitivity analyses.

CONCLUSIONS

The results of these analyses of time-varying concurrent alcohol consumption and smoking suggest that drinking low-to-moderate amounts of alcohol as common in the general population might actually facilitate cessation in non-clinical settings.

Alcohol consumption and chronic atrophic gastritis: population-based study among 9,444 older adults from Germany

Moderate alcohol consumption has been suggested to facilitate elimination of Helicobacter pylori infection which is a key risk factor for chronic atrophic gastritis (CAG) and gastric cancer. The aim of our study was to assess the association of alcohol consumption with CAG among older adults from Germany. In the baseline examination of ESTHER, a population-based study conducted in Saarland, serological measurements of pepsinogen I and II (for CAG definition) and H. pylori antibodies were taken in 9,444 subjects aged 50-74 years. Moderate current (<60 g/week) and lifetime (<or=51,376 g, lowest quartile) alcohol consumption were found to be associated with significantly reduced CAG risk compared to alcohol abstinence with adjusted odds ratios of 0.71 (0.55-0.90) and 0.73 (0.55-0.96), respectively. Inverse associations with CAG were observed for moderate alcohol consumption from both beer and wine, and were slightly attenuated after additional adjustment for H. pylori infection. Our results are consistent with the hypothesis that moderate alcohol consumption may be inversely related to CAG, partly through facilitating the elimination of H. pylori. However, the observed patterns suggest that other mechanisms are likely to contribute to the association as well.

Helicobacter pylori infection and gastric cancer risk: evaluation of 15 H. pylori proteins determined by novel multiplex serology

Infection with Helicobacter pylori is a major cause of gastric cancer (GC). The association likely has been underestimated in the past due to disease-related clearance of the infection. On the other hand, only a minority of the infected individuals develop GC, and better risk stratification is therefore highly desirable. We aimed to assess the association of GC with antibodies to 15 individual H. pylori proteins, determined by novel multiplex serology, to identify potentially relevant risk markers. This analysis was based on 123 GC cases aged 50 to 74 years and 492 age-matched and sex-matched controls from Saarland, Germany. Eight of the antibodies were significantly associated with noncardia GC and seven of them were significantly related to GC at any site. More pronounced associations were observed for noncardia GC; adjusted odds ratios (95% confidence intervals) ranged from 1.60 (1.01-2.54) for HyuA to 5.63 (3.20-9.91) for cytotoxin-associated antigen A (CagA). A dose-response relationship was found between the number of seropositivities and GC (P < 0.001). The seropositivities of CagA and GroEL were found to be independent predictors of GC, which were strongly related to GC risk in a dose-response manner (P < 0.001). In conclusion, GroEL was identified as a new independent risk marker that may contribute to enhanced quantification of H. pylori-related GC risk.

Sibship size, Helicobacter pylori infection and chronic atrophic gastritis: a population-based study among 9444 older adults from Germany

BACKGROUND

Early-life social environment has been suggested to play an important role during the development of Helicobacter pylori-related gastric diseases. We aimed to assess the association of sibship size with H. pylori infection and chronic atrophic gastritis (CAG) in a population-based study from Germany.

METHODS

In the baseline examination of ESTHER, a study conducted in Saarland, serological measurements of pepsinogen I and II and H. pylori antibodies were taken in 9444 participants aged 50-74 years. Information on potential risk factors and medical history were obtained by self-administered standardized questionnaire.

RESULTS

A strong dose-response relationship between sibship size and H. pylori seroprevalence was observed (P < 0.01). Adjusted odds ratios (ORs) 95% confidence interval (CI) for H. pylori seropositivity for subjects with 4, 5, 6 and 7 or more siblings compared with subjects without siblings were 1.45 (1.20-1.77), 1.83 (1.50-2.22) and 1.84 (1.47-2.31), respectively. A large sibship size was also associated with an increased risk of CAG with an adjusted OR of 1.42 (1.01-2.01) for 7 or more compared with less than or equal to 2 siblings. This association was attenuated but not entirely eliminated after additional adjustment for H. pylori infection. Notably, a significant association between large sibship size and CAG was also found among H. pylori-negative subjects.

CONCLUSIONS

Our results suggest that large sibship size is associated with increased H. pylori prevalence and CAG risk. The association with CAG risk may be mediated at least in part by H. pylori infection. However, mechanisms other than H. pylori infection may contribute to the 'sibling effect' as well.

Study of association between atrophic gastritis and body mass index: a cross-sectional study in 10,197 Japanese subjects

OBJECTIVES

The aim of this study was to elucidate the association between body mass index (BMI) and both Helicobacter pylori and atrophic gastritis.

METHODS

The study involved 10,197 subjects participating in a Japanese mass endoscopic gastric cancer screening program. Atrophic gastritis was assessed by pepsinogen I to II ratio.

RESULTS

In logistic regression models, BMI had an inverse association with atrophic gastritis, with the odds ratios (OR) decreasing progressively to 0.67 (95% confidence interval [CI] 0.57-0.79, P<0.0001) in the highest BMI quintiles (BMI >or=25.66) group compared with the lowest BMI quintiles (BMI <20.97) group. In linear regression models, atrophic gastritis predicted BMI (regression coefficient -0.326, 95% CI -0.469, -0.184, P<0.0001), whereas H. pylori antibody was not a predictor (regression coefficient 0.072, 95% CI -0.053, 0.198, P=0.3).

CONCLUSIONS

A small, inverse association between BMI and atrophic gastritis was found in the general population. In contrast, no association was observed between H. pylori seropositivity and BMI.

Smoking cessation and variations in nicotinic acetylcholine receptor subunits alpha-5, alpha-3, and beta-4 genes

BACKGROUND

Evidence has recently accumulated that single nucleotide polymorphisms in the genetic region encoding the nicotinic acetylcholine receptor subunits alpha-5, alpha-3, and beta-4 are associated with smoking and nicotine dependence. We aimed to determine whether these genetic variations are also predictive of smoking cessation.

METHODS

Lifetime history of smoking was assessed by questionnaire at enrolment into a large epidemiological study of the German elderly population (ESTHER study). Cox proportional hazards modeling was applied in a retrospective cohort approach to determine the associations of individual polymorphisms and haplotypes with smoking cessation probability in 1446 subjects who reported regularly smoking more than 20 cigarettes at some point in their lives.

RESULTS

Given the genotype distributions and number of cessation events observed, the power to detect associations ranged from 54% to 97% for hazard ratios of 1.2 to 1.4 in case of the variant with strongest prior evidence (alpha = .05). Nonetheless, neither individual polymorphisms nor inferred multilocus haplotypes were significantly associated with smoking cessation.

CONCLUSIONS

Although the robust association of the nicotinic acetylcholine receptor subunit genes investigated with smoking-related phenotypes is an apparent success story of genetic epidemiology, the respective variations seem to exert no relevant influence on smoking cessation probability in heavy smokers in the general population.

Association between chronic atrophic gastritis and serum antibodies to 15 Helicobacter pylori proteins measured by multiplex serology

Infection with Helicobacter pylori is a major risk factor for chronic atrophic gastritis (CAG), a precursor lesion of intestinal gastric cancer. The pathogenicity of the bacterium is thought to play an important role in determining the extent and severity of clinical outcome. We aimed to assess the associations between CAG and the serostatus of antibodies to 15 H. pylori proteins. The analyses were based on 534 cases with serologically defined CAG and 1,068 age-matched and sex-matched controls participating in a population-based study conducted in Saarland, Germany among 9,953 men and women ages 50 to 74 years. A newly developed H. pylori multiplex serology method was used to detect antibodies specific to 15 H. pylori antigens. Significant associations were observed between seropositivity for all 15 specific antibodies and the presence of CAG. Exclusion of severe cases, who might have lost the infection in the course of CAG progression, substantially increased the observed associations. In H. pylori-seropositive subjects, cytotoxin-associated gene A (CagA), vacuolating toxin (VacA), helicobacter cysteine-rich protein C (HcpC), and the chaperonin GroEL were identified as independent virulence factors for CAG with adjusted odds ratios (95% confidence interval) of 3.52 (2.01-6.10), 3.19 (1.44-7.05), 4.03 (1.53-10.65), and 2.65 (1.06-6.62), respectively; the simultaneous presence of all four independent virulence factors was associated with an 18-fold risk of CAG. In conclusion, HcpC and GroEL were identified as new independent virulence factors, and in combination with the established virulence factors, CagA and VacA, were strongly associated with CAG.

Association of Helicobacter pylori infection with chronic atrophic gastritis: Meta-analyses according to type of disease definition

Helicobacter pylori is a major risk factor for chronic atrophic gastritis (CAG). A large variety of definitions of CAG have been used in epidemiologic studies in the past. The aim of this work was to systematically review and summarize estimates of the association between H. pylori infection and CAG according to the various definitions of CAG. Articles on the association between H. pylori infection and CAG published until July 2007 were identified. Separate meta-analyses were carried out for studies defining CAG based on gastroscopy with biopsy, serum pepsinogen I (PG I) only, the pepsinogen I/pepsinogen II ratio (PG I/PG II ratio) only, or a combination of PG I and the PG I/PG II ratio. Numbers of identified studies and summary odds ratios (OR) (95% confidence intervals) were as follows: gastroscopy with biopsy: n = 34, OR = 6.4 (4.0-10.1); PG I only: n = 13, OR = 0.9 (0.7-1.2); PG I/PG II ratio: n = 8, OR = 7.2 (3.1-16.8); combination of PG I and the PG I/PG II ratio: n = 20, OR = 5.7 (4.4-7.5). Studies with CAG definitions based on gastroscopy with biopsy or the PG I/PG II ratio (alone or in combination with PG I) yield similarly strong associations of H. pylori with CAG. The association is missed entirely in studies where CAG is defined by PG I only.