Tomoyuki Akiyama

Incidence of Small Bowel Injury Induced by Low-Dose Aspirin: A Crossover Study Using Capsule Endoscopy in Healthy Volunteers

Background and Aims: Small intestinal toxicity of low-dose aspirin remains unclear. The purpose of this capsule endoscopy study was to assess the incidence of small bowel injury in healthy volunteers treated with short-term low-dose aspirin. Methods: Healthy subjects were randomly assigned to receive low-dose aspirin for 14 days (Aspirin group) or no drugs for 14 days (Control group). The two treatment occasions were separated by a washout period of at least 4 weeks. All subjects underwent capsule endoscopy at the end of each treatment period. Results: After 2 weeks of treatment, the percentages of subjects with small bowel pathology were 80% in the Aspirin group compared with 20% in the Control group (p = 0.023). The incidence of small bowel mucosal breaks in the Aspirin group was higher than that in the Control group, although the difference was not significant (30 vs. 0%; p = 0.210). Conclusions: This is the first pilot study using capsule endoscopy to report on the relation between small bowel injury and low-dose aspirin. Among the healthy subjects, the short-term administration of low-dose aspirin was associated with a mild mucosal inflammation of the small bowel.

Differentiating sclerosing cholangitis caused by autoimmune pancreatitis and primary sclerosing cholangitis according to endoscopic duodenal papillary features

BACKGROUND Differentiating primary sclerosing cholangitis (PSC) and sclerosing cholangitis caused by autoimmune pancreatitis (SC-AIP) is often challenging. Recently, endoscopic findings of the duodenal papilla in cases with AIP or PSC were reported by Unno and Parlak, although the endoscopic differentiation of these 2 conditions has not yet been fully clarified. OBJECTIVE Our purpose was to clarify the endoscopic findings of the duodenal papilla in patients with SC-AIP and those with PSC and to determine criteria for the differentiation of these conditions. DESIGN Case series. SETTING Retrospective. PATIENTS Twenty-seven patients with SC-AIP and 12 patients with PSC who had undergone ERCP were identified from our database. We reviewed these records to determine whether the duodenal papillary findings (swollen papilla/normal papilla/small papilla) might be potentially useful for differentiating SC-AIP and PSC. Immunohistopathological findings for the duodenal papilla were also examined by using immunoglobulin G4 (IgG4) among the infiltrating plasma cells. INTERVENTIONS ERCP, biopsy specimen taken from duodenal papilla. MAIN OUTCOME MEASUREMENTS The presence of a swollen duodenal papilla with IgG4-positive plasma cells was useful for discriminating SC-AIP from with PSC. RESULTS A swollen duodenal papilla was observed in 63% (17/27) of the patients with SC-AIP, whereas there was no swelling of the duodenal papilla of the patients with PSC. A small papilla was recognized in 50% (6/12) of the patients with PSC. IgG4-positive plasma cells in the duodenal papilla were significantly detected in the patients with SC-AIP but not in the patients with PSC. LIMITATION Single-center study. CONCLUSIONS Characteristic duodenal endoscopic papillary features in patients with SC-AIP, such as a swollen duodenal papilla and positive immunostaining for IgG4, might be helpful for discriminating this condition from PSC.

Visceral obesity and the risk of Barrett's esophagus in Japanese patients with non-alcoholic fatty liver disease

BackgroundThe association between obesity and the risk of Barretts esophagus (BE) is unclear. Furthermore, the association between visceral obesity and the risk of BE is entirely unknown.MethodsWe conducted a retrospective study in 163 patients with non-alcoholic fatty liver disease (NAFLD) who underwent both endoscopy and abdominal CT at an interval of less than a year at our institution. BE was endoscopically diagnosed based on the Prague C & M Criteria. The surface areas of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were calculated from CT images at the level of the umbilicus. The correlations between the BMI, VAT, and SAT and the risk of BE were examined by univariate and multivariate analyses.ResultsSixty-nine of the 163 study participants (42.3%) were diagnosed to have endoscopic BE, which was classified as short-segment BE (SSBE) in almost all of the cases. There were no significant differences in the age or gender distribution between the groups with and without BE. According to the results of the univariate analysis, VAT was significantly associated with the risk of BE; the BMI tended to be higher in the group with BE than in the group without BE, but this relation did not reach statistical significance. VAT was independently associated with the risk of BE even after adjustment for the BMI.ConclusionIn Japanese patients with NAFLD, obesity tended to be associated with the risk of BE, and this risk appeared to be mediated for the most part by abdominal visceral adiposity.

Visceral Obesity and the Risk of Barrett’s Esophagus

It still remains controversial whether simple obesity, as measured by the body mass index (BMI), is an independent risk factor for Barrett’s esophagus (BE). Recent studies have shown abdominal obesity, as defined by the waist circumference (WC) and the waist-to-hip ratio (WHR), to be a risk factor for BE, independent of the BMI, with the association between BMI and BE being no longer observed after adjustment for the WC and WHR. Moreover, visceral obesity, as directly measured by the surface area of the visceral adipose tissue (VAT) on abdominal CT images, has also been reported to have an association with the risk of BE. In addition to the mechanical effects of abdominal obesity, that is, increase of the intra- abdominal pressure by the large amount of adipose tissue, circulating factors secreted from the VAT, such as tumor necrosis factor-α, interleukin-6, leptin, and adiponectin, have also been proposed to be pathogenetically linked to BE and esophageal adenocarcinoma. Obesity is associated with the risk of BE, and this risk appeared to be mediated for the most part by abdominal obesity, especially visceral obesity. This raises several questions regarding the pathogenesis of obesity-related BE. Larger studies with prospective enrollment of patients are required for further examination of this issue.

Alcohol consumption is associated with an increased risk of erosive esophagitis and Barrett's epithelium in Japanese men

BackgroundEvidence regarding the association between alcohol consumption and the gastro-esophageal reflux disease (GERD) spectrum has been conflicting. We examined the association between alcohol consumption and erosive esophagitis and Barretts epithelium in Japanese men.MethodsThe study population comprised 463 men subjects who had undergone an upper endoscopy at the Gastroenterology Division of Yokohama City University Hospital between August 2005 and July 2006. The presence of erosive esophagitis and Barretts epithelium was diagnosed based on the Los Angeles Classification and the Prague C and M Criteria, respectively. We divided the study population into four groups: never drinkers, light drinkers (less than 25.0 g of ethanol per day), moderate drinkers (25.0 to 50.0 g of ethanol per day), and heavy drinkers (more than 50.0 g of ethanol per day). A linear regression of the logistic regression analysis was used to analyze the dose-response trends.ResultsCompared with never drinkers, light drinkers (less than 25.0 g ethanol per day), moderate drinkers (25.0 to 50.0 g per day), and heavy drinkers (more than 50.0 g per day) had ORs for erosive esophagitis of 1.110 (95% CI: 0.553 – 2.228, p = 0.7688), 1.880 (95% CI: 1.015 – 3.484, p = 0.0445) and 1.988 (95% CI: 1.120 – 3.534, p = 0.0190), respectively. These groups had ORs for Barretts epithelium of 1.278 (95% CI: 0.752 – 2.170, p = 0.3643), 1.458 (95% CI: 0.873 – 2.433, p = 0.1500), and 1.912 (95% CI: 1.185 – 3.086, p = 0.0079), respectively. The odds ratios/grams (alcohol)/day of dose response trends for erosive esophagitis and Barretts epithelium were 1.015 (95% CI: 1.004–1.026, p = 0.0066) and 1.012 (95% CI: 1.003–1.021, p = 0.0079), respectively.ConclusionThese findings suggest that alcohol consumption in Japanese men tends to be associated with an increased risk of erosive esophagitis and Barretts epithelium.

Early effects of peppermint oil on gastric emptying: a crossover study using a continuous real-time 13C breath test (BreathID system)

BackgroundThe aim of this study was to determine whether there was a correlation between peppermint oil and gastric emptying by using a novel noninvasive technique for measuring gastric emptying with a continuous real-time 13C breath test (BreathID system, Oridion, Israel).MethodsTen healthy male volunteers participated in this randomized, two-way crossover study. The subjects were randomly assigned to receive a test meal (200 kcal per 200 ml) containing 0.64 ml of peppermint oil or the test meal alone, after fasting overnight. A 13C-acetic acid breath test was continuously performed with the BreathID system, which monitors gastric emptying, for 4 h after the administration of the test meal. Using Oridion Research Software (β version), the time for emptying of 50% of the labeled meals (T 1/2), the analog to the scintigraphy lag time for 10% emptying of the labeled meal (T lag), the gastric emptying coefficient (GEC), and the regression-estimated constants (β and κ) were calculated. The parameters between two occasions were compared using the Wilcoxon signed-rank test.ResultsAfter peppermint oil intake, the T lag and β constant were significantly decreased. No significant differences in T 1/2, GEC, or κ were observed between the two occasions.ConclusionsThe decrease in the T lag and β constant suggests acceleration of gastric emptying during the early phase. This study showed that peppermint oil enhances gastric emptying, suggesting the potential use of peppermint oil in clinical settings for patients with functional gastrointestinal disorders.

Risk factors for colonic diverticular hemorrhage: Japanese multicenter study.

Background and Aim: Diverticular hemorrhage is the common cause of lower gastrointestinal bleeding, and its incidence has been increasing in Japan. However, the exact cause of diverticular hemorrhage is not well understood. We investigated the risk factors for diverticular hemorrhage. Methods: We selected 103 patients with diverticular hemorrhage as cases and patients with colonic diverticulosis without a history of bleeding were selected as control subjects, exactly matched for age and gender. We collected the data from the medical records of each of the patients, such as those related to the comorbidities, medications and findings of colonoscopy, and conducted a matched case-control study to analyze the risk factors for diverticular hemorrhage. Results: Both groups were composed of 75 men and 28 women. The median age of the patients in both groups was 72.0 years (47.0–87.0). The body weight (p = 0.0065), body mass index (p = 0.006), prevalence of hypertension (p = 0.0242), prevalence of ischemic heart disease (p = 0.0015), and frequency of use of low-dose aspirin (p = 0.042) were significantly different between the two groups. The percentage of patients with bilateral diverticula, that is, diverticula on both the right and left hemicolon, was significantly higher in the diverticular hemorrhage group (p = 0.0011). Multiple regression analysis identified only the diverticular location as being significantly associated with the risk of diverticular hemorrhage (p = 0.0021). Conclusions: Only the diverticular location (bilateral) was found to be an independent risk factor for diverticular hemorrhage.

Gene expression profiling of non-alcoholic steatohepatitis using gene set enrichment analysis

Aim:  Non‐alcoholic steatohepatitis (NASH) is a subset of non‐alcoholic fatty liver disease (NAFLD) and sometimes progresses to cirrhosis and liver failure. In this study we analyzed the expression profile of genes and biological pathways involved in NASH in comparison with non‐NASH by gene set enrichment analysis (GSEA) employing a DNA microarray technique.

Risk Factors for the Progression of Endoscopic Barrett’s Epithelium in Japan: A Multivariate Analysis Based on the Prague C & M Criteria

Purpose To determine the prevalence and progression of Barrett’s epithelium and associated risk factors in Japan. Methods The study population comprised 869 cases. Endoscopic Barrett’s epithelium was diagnosed based on the Prague C & M Criteria. The correlations of clinical factors with the prevalence and progression of endoscopic Barrett’s epithelium were examined. Results Endoscopic Barrett’s epithelium was diagnosed in 374 cases (43%), in the majority of which the diagnosis was short-segment Barrett’s esophagus. The progression of Barrett’s epithelium was identified in 47 cases. In univariate and multiple logistic regression analyses, aging, smoking habit, and erosive esophagitis were significantly associated with the prevalence of Barrett’s epithelium, whereas aging and erosive esophagitis, especially severe erosive esophagitis, were significant contributing factors to the progression of Barrett’s epithelium. Conclusions Forty-three percent of the total study population was diagnosed as having endoscopic Barrett’s epithelium. During the follow-up period, 12.6% of the cases with Barrett’s epithelium exhibited progression which was associated with aging and severe erosive esophagitis.

Macroscopic extent of gastric mucosal atrophy: increased risk factor for esophageal squamous cell carcinoma in Japan

BackgroundWe aimed to estimate whether the macroscopic extent of gastric mucosal atrophy is associated with a risk for esophageal squamous cell carcinoma using a case-control study in Japanese subjects, a population known to have a high prevalence of CagA-positive H. pylori infection.MethodsTwo hundred and fifty-three patients who were diagnosed as having esophageal squamous cell carcinoma, and 253 sex- and age-matched controls were enrolled in the present study. The macroscopic extent of gastric mucosal atrophy was evaluated based on the Kimura and Takemoto Classification. A conditional logistic regression model with adjustment for potential confounding factors was used to assess the associations.ResultsBody gastritis, defined endoscopically, was independently associated with an increased risk for esophageal squamous cell carcinoma.ConclusionOur findings suggest that macroscopic body gastritis may be a risk factor for esophageal squamous cell carcinoma in Japan. Further studies are needed to confirm these findings.