Environmental Factors in Helicobacter pylori-Related Gastric Precancerous Lesions in Venezuela

Phytochemical Index and the Risk of Gastritis/Gastric Ulcer among Korean Adults: A Prospective Cohort Study

Phytochemicals found in fruits, vegetables, and plant-based foods have potential protective effects against various diseases, including gastric disorders. This study aimed to analyze the longitudinal association between phytochemical intake and the risk of gastritis/gastric ulcer in Korean adults. This was a prospective cohort study, a community-based cohort conducted as part of the Korean Genome and Epidemiology Study, examining the association between phytochemical intake and the risk of gastritis/gastric ulcer in Korean adults. Dietary information was collected using a validated semi-quantitative food frequency questionnaire, and the phytochemical index (PI) was calculated. The study included 7377 Korean men and women aged 40-69 years without gastritis/gastric ulcer at baseline of the Korea Association Resource study in Korea. The incidence of gastritis/gastric ulcer was determined using a survey questionnaire administered by trained staff. Multivariate Cox proportional hazards regression was used to calculate the hazard ratio and 95% confidence interval to determine the association between PI and risk of gastritis/gastric ulcer. During the median follow-up period of 9.50 years, 729 cases were reported. The fully adjusted model showed a significantly lower risk of gastritis/gastric ulcer in the highest PI quartile compared to the lowest (hazard ratio: 0.78, 95% confidence interval: 0.61-0.98), and this association was linear (p for trend = 0.01). This research indicates that incorporating foods abundant in phytochemicals into one's diet could be associated with a reduced risk of developing gastritis/gastric ulcers. These findings underscore the importance of further investigating the role of phytochemical-rich diets in gastrointestinal health, as demonstrated in this study.

Risk factors in the development of gastric adenocarcinoma in the general population: A cross-sectional study of the Wuwei Cohort

Several risk factors have been identified for the development of gastric adenocarcinoma (GAC), where the control group was usually a healthy population. However, it is unclear at what stage known risk factor exert their influence toward the progression to cancer. Based on the Wuwei Cohort, we enrolled 1,739 patients with chronic non-atrophic gastritis (no-CAG), 3,409 patients with chronic atrophic gastritis (CAG), 1,757 patients with intestinal metaplasia (IM), 2,239 patients with low-grade dysplasia (LGD), and 182 patients with high-grade dysplasia (HGD) or GAC to assess the risk factors between each two consecutive stages from no-CAG to GAC/HGD using adjusted logistic regression. We found that different groups of risk factors were associated with different stages. Age, occupation of farmer, low annual family income, Helicobacter pylori (H. pylori) infection, drinking, eating hot food, histories of gastritis and peptic ulcer were associated with the development of CAG. Age, illiteracy, H. pylori infection, smoking, eating hot food, eating quickly, and histories of gastritis and gallbladder diseases were associated with the progression to IM from CAG. Male, occupation of farmer and history of peptic ulcer were associated with the development of LGD from IM. Age, male and polyp history appeared to be risk factors associated with the development of GAC/HGD from LGD. In conclusion, it seems that most risk factors function more as a set of switches that initiated the GAC carcinogenesis. H. Pylori eradication and control of other risk factors should be conducted before IM to decrease the incidence of GAC.

Chinese integrated guideline on the management of gastric precancerous conditions and lesions

The standardized diagnosis and management of gastric precancerous conditions and lesions are important to prevent gastric cancer. This guideline, created by 5 traditional Chinese medicine and Western medicine associations, based on the current morbidity and diagnosis and treatment of gastric precancerous conditions and lesions, provides specific key points and strategies for diagnosis and treatment in the following five aspects: definition and epidemiology, diagnosis and stage, surveillance, treatment and efficacy evaluation. It is hoped that these aspects, assessed by integrating Western medicine and traditional Chinese medicine and involving multidisciplinary participation, will play a guiding role in clinical diagnosis and treatment and achieve effective secondary prevention of gastric cancer.

TAS2R38 polymorphisms, Helicobacter pylori infection and susceptibility to gastric cancer and premalignant gastric lesions

BACKGROUND

Gastric cancer is worldwide the fourth more common cancer type by incidence, and the third by mortality. We analyzed three missense variants of TAS2R38 gene: rs713598 (A49P), rs1726866 (V262A), and rs10246939 (I296V). These variants and their combination in haplotypes (proline, alanine and valine/tasters or alanine, valine and isoleucine/nontasters) and diplotypes are responsible for individual differences in bitter perception. The single-nucleotide polymorphisms and the related phenotypes are known to be associated with susceptibility to Gram-negative bacterial infections, such as Helicobacter pylori , and with risk of various cancer types. An association between intermediate tasters (as defined by TAS2R38 diplotypes) and increased risk of gastric cancer was reported in a Korean population.

METHODS

We analyzed 2616 individuals of Latin American origin, representing the whole spectrum of lesions from gastritis to gastric cancer.

RESULTS

Comparing cancer cases vs. noncancers we observed a decrease in risk associated with heterozygous carriers of rs10246939 ( P  = 0.006) and rs1726866 ( P  = 0.003) when compared with homozygotes of the more common allele. Also, the analysis of diplotypes/phenotypes reflected the same association, with super-tasters showing a borderline increased risk of developing gastric cancer compared to medium-tasters [odds ratio (OR) = 1.63; 95% confidence interval (CI), 1.04-2.56; P  = 0.033]. Also, nontasters showed an increased risk when compared to medium-tasters although not reaching statistical significance (OR = 1.58; 95% CI, 0.80-2.87; P  = 0.203). We also tested the interactions between the TAS2R38 genotypes and H. pylori cagA status in a subset of samples and found no interaction.

CONCLUSION

In conclusion, our results suggest only a modest contribution of TAS2R38 gene genetic variability in gastric cancer etiology.

Associations of Duration, Intensity, and Quantity of Smoking With Risk of Gastric Intestinal Metaplasia

GOAL

Determine whether various dimensions of smoking increase risk for gastric intestinal metaplasia.

BACKGROUND

Cigarette smoking has been implicated in the etiology of gastric cancer, but it is not clear if smoking is a risk factor for gastric intestinal metaplasia, a precursor lesion of gastric cancer.

MATERIALS AND METHODS

We compared data from 385 gastric intestinal metaplasia cases and 1577 controls without gastric intestinal metaplasia recruited into a cross-sectional study at the Michael E. DeBakey VA Medical Center in Houston, Texas. All participants completed standardized questionnaires and underwent a study endoscopy with gastric mapping biopsies. Gastric intestinal metaplasia cases included participants with intestinal metaplasia on any noncardia gastric biopsy. We calculated odds ratios and associated 95% confidence intervals using multivariable logistic regression models.

RESULTS

Compared with never smokers, current smokers had 2-fold increased risk for gastric intestinal metaplasia (odds ratio, 2.05; 95% confidence interval, 1.47-2.85). Among ever smokers, increasing duration and total dose were significantly associated with increased risk for gastric intestinal metaplasia (P-trend, 0.004 and 0.01, respectively). Among former smokers, risk for gastric intestinal metaplasia decreased over time and was no different to never smokers after 15 years smoking cessation. Cases with gastric intestinal metaplasia were more likely than controls to have Helicobacter pylori infection (53.2% vs. 21.7%); however, smoking effect on gastric intestinal metaplasia was not different by H. pylori infection status.

CONCLUSIONS

Cigarette smoking is a risk factor for gastric intestinal metaplasia. Risk of gastric intestinal metaplasia among former smokers remained significantly elevated until 15 years postcessation.

Helicobacter pylori Infection and Serum Pepsinogen Level With the Risk of Gastric Precancerous Conditions: A Cross-sectional Study of High-risk Gastric Cancer Population in China

BACKGROUND AND AIM

Gastric precancerous conditions are generally considered to play an essential role in the gastric carcinogenesis cascade. This study identified risk factors of gastric precancerous conditions in a nationwide multicenter cross-sectional study.

METHODS

Individuals who made their visit to 115 hospitals in China for gastric cancer screening were recruited. Lifestyle habits and personal information were collected through a series of questionnaires. Serum biomarker test (pepsinogen I, pepsinogen II, gastrin-17, and anti-Helicobacter pylori immunoglobulin G antibody) and endoscopy were then performed. Risk factors for gastric precancerous conditions were identified by univariate and multivariate analyses.

RESULTS

Of 14,929 subjects eligible for analysis, 4477 (30.0%) developed gastric precancerous conditions and 405 (2.71%) developed gastric cancer. In multiple logistic regression, precancerous conditions were associated with advanced age [odds ratio (OR)=1.027; 95% confidence interval (Cl), 1.023-1.032; P<0.001], male gender (OR=1.303; 95% Cl, 1.188-1.429; P<0.001), H. pylori infection (OR=1.377; 95% Cl, 1.272-1.490, P<0.001), and smoking (OR=1.142; 95% Cl, 1.005-1.298, P=0.004), whereas they were inversely correlated with white meat intake (OR=0.731; 95% Cl, 0.673-0.794; P<0.001) and pepsinogen I level (30 to 70 subgroup OR=1.536; 95% Cl, 1.163-2.028; P=0.002; <30 subgroup OR=1.354; 95% Cl, 1.206-1.520; P<0.001). Also, the authors observed a statistically lower prevalence of reflux esophagitis (2.8% vs. 4.7%) and of gastric polyps (11.0% vs. 13.7%) in H. pylori-infected population.

CONCLUSIONS

Patients with H. pylori have a 1.4-fold higher risk of having gastric precancerous conditions. Besides, precancerous conditions were associated with advanced age, male gender, H. pylori infection, and smoking in a large population. However, regular white meat intake and higher pepsinogen I level were associated with reduced risk of having precancerous lesions.

Dietary Factors and Gastric Intestinal Metaplasia Risk Among US Veterans

BACKGROUND

Studies on diet and gastric intestinal metaplasia (GIM) risk are lacking in US populations.

AIM

To determine the associations of dietary factors and risk of GIM among a US population with typical American diet.

METHODS

We analyzed data from a cross-sectional study of veterans attending primary care and endoscopy clinics at the Houston VA Medical Center. Patients completed a 110-item Block Food Frequency Questionnaire then underwent upper endoscopy with gastric mapping biopsies. We compared cases defined by GIM on ≥ 1 non-cardia gastric biopsy to controls without GIM. Associations of dietary factors and GIM were estimated using logistic regression models as odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Among 423 GIM cases and 1796 controls, cases were older (62.1 vs. 59.9 years) and more likely to be male (97.2% vs. 90.8%) and non-White (58.6% vs. 39.0%). GIM cases had lower fat intake (percent kcal from fat tertile 1: 43.6% vs. 33.4%) and higher carbohydrate intake (percent kcal from carbohydrate T3: 41.8% vs. 33.3%) than controls. Adjusting for age, gender, race, smoking, and Helicobacter pylori, percent kcal from carbohydrates (T3 vs. T1: OR 1.35, 95% CI 1.08-1.67), fruit intake (T3 vs. T1: OR 1.28, 95% CI 1.02-1.61), and fiber intake (T3 vs. T1: OR 1.37, 95% CI 1.04-1.80) were associated with GIM. In subgroup analyses, these associations were primarily seen in non-White patients.

CONCLUSIONS

Few dietary factors, including high carbohydrate intake, are associated with increased risk of GIM in US populations, independent of H. pylori or smoking.

Systematic review of the prevalence of gastric intestinal metaplasia and its area-level association with smoking

OBJECTIVES

We aimed to show an area-level association between the frequency of intestinal metaplasia (IM) in Helicobacter pylori-infected patients and tobacco consumption.

METHODS

We systematically reviewed the literature to retrieve data on the prevalence of IM in different countries and performed an ecological analysis to quantify the association between the prevalence of IM among infected subjects and smoking, using data on national tobacco availability. Articles evaluating IM in the general population or in dyspeptic patients were identified by a MEDLINE search. We selected one study per country, giving preference to those for which the study design/populations evaluated provided the highest external validity and inter-study comparability of methodology.

RESULTS

This systematic review of published data retrieved information for 29 countries from 5 continents depicting a wide variation in the prevalence of IM among H. pylori-infected subjects in different regions, ranging from 3% in Argentina to 55% in New Zealand. In countries exhibiting a simultaneously high prevalence of infection and low incidence of gastric cancer, IM was also relatively infrequent (Thailand, 6%; India, 8.2%; Nigeria, 11.1%; Gambia, 11.8%; Saudi Arabia, 15.5%; Iran, 15.6%; Egypt, 24.4%). A significant correlation was observed between IM prevalence in infected subjects and tobacco availability (r = 0.45; p = 0.02).

CONCLUSIONS

Our results show that the concept of the African and Asian "enigmas" may be extended to precancerous lesions. Tobacco availability was positively associated with the prevalence of IM among H. pylori-infected subjects at an area level.

[Prevalence of Helicobacter pylori infection and gastric cancer precursor lesions in patients with dyspepsia]

BACKGROUND

Helicobacter pylori infection has been considered to play significant role in gastric carcinogenesis, but only a minority of people who harbor this organism will develop gastric cancer. H. pylori infection first causes chronic non atrophic gastritis. Chronic non atrophic gastritis may evolve to atrophic gastritis and intestinal metaplasia and finally to dysplasia and adenocarcinoma.

AIMS

To estimate the prevalence of H. pylori infection and the precancerous gastric lesions and their relationship, in patients with dyspeptic symptoms who underwent upper gastrointestinal endoscopy at a reference center in the central region of Rio Grande do Sul state, Brazil.

METHODS

We analyzed gastric biopsies taken from corpus and antrum of patients who underwent upper gastrointestinal endoscopy for H. pylori detection, between 1994 and 2003. According to Sydney system, chronic non atrophic gastritis, atrophic gastritis and intestinal metaplasia were diagnosed by histological examination (H-E stain). The histological diagnoses were related to H. pylori infection status.

RESULTS

Biopsies from 2,019 patients were included in the study. Patients mean age was 52 (+/-15) and 59% were female. Seventy six percent had H. pylori infection. Normal mucosa, chronic non atrophic gastritis, atrophic gastritis and intestinal metaplasia were diagnosed in 5%, 77%, 3% and 15%, respectively. The OR for any degree of gastric mucosa lesion in infected patients was 10 (CI95% 6.50 - 17%). The OR for infected patients had chronic non atrophic gastritis was 3 (CI95% 2,2 - 3,4). The OR for infected patients had atrophic gastritis or intestinal metaplasia was less than 1.

CONCLUSIONS

The prevalence of H. pylori infection in this population was high (76%) and infected individuals had the probability 10 folds greater than non infected individuals to have any lesion of gastric mucosa. The prevalence of precancerous lesions was 77% for non atrophic chronic gastritis, 3% for atrophic gastritis and 15% for intestinal metaplasia. Infected patients had risk 3 folds greater than non-infected for the occurrence of non atrophic chronic gastritis. H. pylori infection did not show risk for occurrence of atrophic gastritis and intestinal metaplasia, suggesting that other risk factors should be involved in the carcinogenesis process.

Smoking, Helicobacter pylori virulence, and type of intestinal metaplasia in Portuguese males

High-virulence Helicobacter pylori strains and smoking increase the risk of gastric precancerous lesions. However, its association with specific types of intestinal metaplasia has been poorly studied. We aimed to quantify the association between different types of intestinal metaplasia (complete, incomplete, and mixed) and these two risk factors. Male volunteers (n = 227) underwent an upper digestive endoscopy and completed symptoms and lifestyle questionnaires. A histologic diagnosis was assigned based on the lesions found in any of the biopsy specimens (antrum, body, or incisura). H. pylori vacA and cagA were directly genotyped by multiplex PCR and reverse hybridization. Each participant's smoking status at the time of endoscopy was assessed. Logistic and multinomial logistic regression models were fitted (including H. pylori virulence, smoking, age, and education as independent variables) using normal/chronic nonatrophic gastritis as the reference category. Compared with never smokers infected with low-virulence strains, the risk of intestinal metaplasia was increased in subjects infected with high-virulence strains [odds ratio (OR), 5.74; 95% confidence interval (95% CI), 1.68-19.63] and in ever smokers (OR, 3.54; 95% CI, 1.30-9.61). In ever smokers infected with high-virulence H. pylori strains, the risk of intestinal metaplasia was further increased (OR, 8.61; 95% CI, 3.07-24.17). Infection with high-virulence strains significantly increased the risk of incomplete (OR, 9.81; 95% CI, 2.39-40.31) and mixed (OR, 3.28; 95% CI, 1.51-7.14) intestinal metaplasia. Complete (OR, 2.82; 95% CI, 1.01-7.88) and mixed (OR, 2.97; 95% CI, 1.12-7.84) intestinal metaplasia were more frequent among ever smokers. High-virulence H. pylori strains and smoking are differentially associated with the complete and incomplete types of intestinal metaplasia, suggesting divergent pathways in gastric carcinogenesis.