Tomoari Kamada

Helicobacter pylori eradication therapy improves atrophic gastritis and intestinal metaplasia: a 5-year prospective study of patients with atrophic gastritis.

Aim : To investigate the effect of the eradication of Helicobacter pylori on histological gastritis.

Negative association between Helicobacter pylori infection and reflux esophagitis in older patients: case-control study in Japan.

Background. Recent studies have clarified a close association between H. pylori infection and gastritis, peptic ulcer disease, and gastric cancer, but there is little information concerning the relationship between H. pylori infection and reflux esophagitis (RE). We investigated the relationship between H. pylori, RE, and corpus gastritis.

Meta-analysis of the effects of prokinetic agents in patients with functional dyspepsia.

Background:  Functional dyspepsia (FD) is often treated with prokinetic agents; however, the efficacy of prokinetic agents in patients with FD has been questioned recently. The aim of this study was to perform a meta‐analysis of the effects of prokinetic agents in patients with FD.

The Role of Endoscopic Findings for the Diagnosis of Helicobacter pylori Infection: Evaluation in a Country with High Prevalence of Atrophic Gastritis

This study examines endoscopic findings in the diagnosis of Helicobacter pylori (H. pylori) in the Japanese population.

Therapeutic efficacy of acotiamide in patients with functional dyspepsia based on enhanced postprandial gastric accommodation and emptying: randomized controlled study evaluation by real-time ultrasonography.

Background  Improvement in subjective symptoms has been reported in functional dyspepsia (FD) patients administered with acotiamide. Improvement was confirmed in meal‐related symptoms, such as postprandial fullness, upper abdominal bloating, and early satiety. We examined the mechanism underlying the effects of acotiamide on gastric accommodation reflex (GAR) and gastroduodenal motility in FD patients.

Clinical features of gastric cancer discovered after successful eradication of Helicobacter pylori: results from a 9‐year prospective follow‐up study in Japan

Background : Eradication of Helicobacter pylori is expected to prevent the development of gastric cancer. However, gastric cancer is sometimes discovered after successful eradication of H. pylori.

Helicobacter pylori Infection Is a Major Risk Factor for Gastric Carcinoma in Young Patients

Background: Helicobacter pylori has been established as a risk factor for gastric carcinoma (GCa). Since before the discovery of H. pylori, atrophic gastritis and intestinal metaplasia have been linked to GCa, especially the intestinal-type tumor. The prevalence of H. pylori infection and atrophic gastritis increase with age. Thus, analysis of H. pylori infection in young patients with GCa could help clarify the role of this bacterium in the development of GCa. Accordingly, we investigated the relationship between H. pylori infection, GCa, and histologic gastritis in patients less than 30 years old. Methods: Fifty GCa patients less than 30 years (mean, 26.4 years) and 100 sex- and age-matched controls (mean, 26.8 years) were examined for the presence of H. pylori infection and histologic gastritis. Results: The prevalence of H. pylori infection was significantly higher in GCa patients than in controls (94% versus 40%, P < 0.01). Its prevalence was not associated with tumor location, tumor stage, or histologic type. Gastritis, atrophy, and intestinal metaplasia significantly increased the risk of GCa. By means of multiple logistic regression analysis, the odds ratio for the risk of GCa in H. pylori-positive subjects was found to be 23.5 (95% confidence interval, 6.84-80.7). Conclusions: We confirmed a strong association between H. pylori infection and GCa in young patients. Along with H. pylori infection, histologic gastritis might play an important role in the pathogenesis of GCa in these patients.BACKGROUND Helicobacter pylori has been established as a risk factor for gastric carcinoma (GCa). Since before the discovery of H. pylori, atrophic gastritis and intestinal metaplasia have been linked to GCa, especially the intestinal-type tumor. The prevalence of H. pylori infection and atrophic gastritis increase with age. Thus, analysis of H. pylori infection in young patients with GCa could help clarify the role of this bacterium in the development of GCa. Accordingly, we investigated the relationship between H. pylori infection, GCa, and histologic gastritis in patients less than 30 years old. METHODS Fifty GCa patients less than 30 years (mean, 26.4 years) and 100 sex- and age-matched controls (mean, 26.8 years) were examined for the presence of H. pylori infection and histologic gastritis. RESULTS The prevalence of H. pylori infection was significantly higher in GCa patients than in controls (94% versus 40%, P < 0.01). Its prevalence was not associated with tumor location, tumor stage, or histologic type. Gastritis, atrophy, and intestinal metaplasia significantly increased the risk of GCa. By means of multiple logistic regression analysis, the odds ratio for the risk of GCa in H. pylori-positive subjects was found to be 23.5 (95% confidence interval, 6.84-80.7). CONCLUSIONS We confirmed a strong association between H. pylori infection and GCa in young patients. Along with H. pylori infection, histologic gastritis might play an important role in the pathogenesis of GCa in these patients.

Low-dose aspirin-induced gastrointestinal diseases: past, present, and future

Meta-analyses of randomized, placebo-controlled trials of low-dose aspirin indicate that aspirin approximately doubles the risk of major GI bleeding compared with placebo. The risk in Japanese may possibly be higher compared to Western populations, although the evidence is still lacking and prospective studies are required. Prior GI events, older age, and use of other injurious medicines such as NSAIDs, anticoagulants, and corticosteroids seem to be factors associated with an increased risk for upper GI bleeding among aspirin users. Prospective studies are needed to identify specific risk factors for upper GI bleeding in Japanese patients taking low-dose aspirin. There are many potential gastroprotective drugs available in Japan, and studies are needed to assess the relative effectiveness of various strategies including PPI use for the prevention of aspirin-related upper GI ulcer complications and whether any of these other agents also provide protection against small bowel or colonic damage. Aspirin-induced enteropathy is now increasingly being recognized and is presumably not uncommon, and the availability of new imaging techniques for the small intestine and noninvasive tests such as fecal calprotectin should allow rapid progress in this important area.

REDUCED INCIDENCE OF HELICOBACTER PYLORI INFECTION IN YOUNG JAPANESE PERSONS BETWEEN THE 1970S AND THE 1990S

Although the incidence of gastric carcinoma in Japan has declined in the past several decades, there is no information about trends in helicobacter pylori infection. The purpose of the study was to clarify trends in H. pylori infection and in histologic gastritis in young Japanese subjects evaluated between 1975 and 1978 (the 1970s) versus 1991 and 1994 (the 1990s). The prevalence of H. pylori infection and the grade of gastritis in biopsy specimens were evaluated in 173 young Japanese without localized lesions in the upper gastrointestinal tract. Findings in 75 specimens obtained from subjects in the 1970s were compared with those of 98 specimens obtained from subjects in the 1990s. The prevalence of H. pylori infection in the 1970s (54.7%) was significantly higher than that in the 1990s (28.6%) (p < 0.01). The grade of inflammation and the prevalence of both mucosal atrophy and intestinal metaplasia also were significantly higher in the 1970s than in the 1990s (p < 0.01 and p < 0.05). Our data thus show a trend toward a reduced prevalence of H. pylori infection and of histologically apparent gastritis (especially atrophic gastritis). This decrease may be linked to the reported decline of gastric carcinoma in Japan.

The long-term effect of Helicobacter pylori eradication therapy on symptoms in dyspeptic patients with fundic atrophic gastritis.

Aim : To investigate whether curing Helicobacter pylori infection improves symptoms over the long‐term in Japanese patients with nonulcer dyspepsia and fundic atrophic gastritis.