Background: Functional dyspepsia (FD) is a disorder that presents with chronic dyspepsia, which is not only very common but also highly affects quality of life of the patients. In Japan, FD became a disease name for national insurance in 2013, and has been gradually recognized, though still not satisfactory. Following the revision policy of Japanese Society of Gastroenterology (JSGE), the first version of FD guideline was revised this time.Method: Like previously, the guideline was created by the GRADE (grading of recommendations assessment, development and evaluation) system, but this time, the questions were classified to background questions (BQs, 24 already clarified issues), future research questions (FRQs, 9 issues cannot be addressed with insufficient evidence), and 7 clinical questions that are mainly associated with treatment.Results and Conclusion: These revised guidelines have two major features. The first is the new position of endoscopy in the flow of FD diagnosis. While endoscopy was required to all cases for diagnosis of FD, the revised guidelines specify the necessity of endoscopy only in cases where organic disease is suspected. The second feature is that the drug treatment options have been changed to reflect the latest evidence. The first-line treatment includes gastric acid-secretion inhibitors, acetylcholinesterase (AChE) inhibitors (acotiamide, a prokinetic agent), and Japanese herbal medicine (rikkunshito). The second-line treatment includes anxiolytics /antidepressant, prokinetics other than acotiamide (dopamine receptor antagonists, 5-HT4 receptor agonists), and Japanese herbal medicines other than rikkunshito. The patients not responding to these treatment regimens are regarded as refractory FD.

Functional dyspepsia (FD) is a common condition in the general population; however, its treatment remains a challenge. The aim of this study was to examine the efficacy of tandospirone citrate, a new partial agonist of the 5-hydroxytryptamine 1A (5-HT1A) receptor, in improving the symptoms of patients with FD. In this double-blind, placebo-controlled, multicenter study, FD patients were randomized to treatment with 10 mg t.i.d. tandospirone citrate or to placebo for 4 weeks. The primary end point was change in abdominal symptom scores. The difference in the proportion of responders (a total abdominal symptom score of 0 or 1) was also assessed. The quality-of-life questionnaire, the SF-8, and a psychological test questionnaire, the State-Trait Anxiety Inventory (STAI), were completed at baseline and at weekly intervals. Data were available for 144 patients: 73 for tandospirone and 71 for placebo. Improvements in total abdominal scores were significantly larger with tandospirone than placebo at weeks 1, 2, and 4. Significantly greater improvements in the tandospirone group were observed in upper abdominal pain (P=0.02) and discomfort (P=0.002) at week 4. The proportion of responders was significantly greater in the active treatment arm at weeks 3 (P=0.017) and 4 (P=0.0016). Significant improvements in STAI (P<0.0001) were reported in both arms, as well as in the majority of questions in the SF-8 (P=0.04). No serious adverse events were reported, with similar rates in both study arms. Despite a considerable placebo effect, the benefits of tandospirone were shown in terms of improvement in abdominal symptom scores.

Summary: Background: Vonoprazan is a new potassium‐competitive acid blocker for treatment of acid‐related diseases.Aim: To conduct two randomised‐controlled trials, to evaluate the non‐inferiority of vonoprazan vs. lansoprazole, a proton pump inhibitor, for treatment of gastric ulcer (GU) or duodenal ulcer (DU).Methods: Patients aged ≥20 years with ≥1 endoscopically‐confirmed GU or DU (≥5 mm white coating) were randomised 1:1 using double‐dummy blinding to receive lansoprazole (30 mg) or vonoprazan (20 mg) for 8 (GU study) or 6 (DU study) weeks. The primary endpoint was the proportion of patients with endoscopically confirmed healed GU or DU.Results: For GU, 93.5% (216/231) of vonoprazan‐treated patients and 93.8% (211/225) of lansoprazole‐treated patients achieved healed GU; non‐inferiority of vonoprazan to lansoprazole was confirmed [difference = −0.3% (95% CI −4.750, 4.208); P = 0.0011]. For DU, 95.5% (170/178) of vonoprazan‐treated patients and 98.3% (177/180) of lansoprazole‐treated patients achieved healed DU; non‐inferiority to lansoprazole was not confirmed [difference = −2.8% (95% CI −6.400, 0.745); P = 0.0654]. The incidences of treatment‐emergent adverse events were slightly lower for GU and slightly higher for DU with vonoprazan than with lansoprazole. There was one death (subarachnoid haemorrhage) in the vonoprazan group (DU). The possibility of a relationship between this unexpected patient death and the study drug could not be ruled out. In both studies, increases in serum gastrin levels were greater in vonoprazan‐treated vs. lansoprazole‐treated patients; levels returned to baseline after treatment in both groups.Conclusions: Vonoprazan 20 mg has a similar tolerability profile to lansoprazole 30 mg and is non‐inferior with respect to GU healing and has similar efficacy for DU healing.

Background and Aim: Functional gastrointestinal disorders are a group of stress‐sensitive gut–brain disorders. The COVID‐19 outbreak has caused immense stress and anxiety among the general public. Strict measures to counter COVID‐19 emergency, including physical distancing, have also taken a toll on physical and mental health. We investigated the impact of the COVID‐19 pandemic on the gastrointestinal and psychological symptoms of functional dyspepsia (FD) and irritable bowel syndrome (IBS).Methods: An online survey was conducted in Japan for a group of randomly assigned panelists from May 26 to 27, 2020. Each respondent answered a questionnaire on stress, physical distancing, and worries about COVID‐19. Gastrointestinal symptoms were assessed to diagnose FD and IBS (Rome III), and psychological symptoms were assessed using the Hospital Anxiety and Depression Scale.Results: A total of 5157 subjects were finally enrolled, with FD in 8.5%, IBS in 16.6%, and FD–IBS overlap in 4.0%. For both gastrointestinal and psychological symptoms, respondents with FD–IBS overlap showed the worst scores, followed by IBS‐alone, then FD‐alone respondents. During the COVID‐19 pandemic, 11.9% of respondents reported deterioration and 2.8% reported improvement of gastrointestinal symptoms. FD–IBS overlap, psychological disease comorbidity, and stress at work/school were significantly associated with symptom deterioration. Younger age, commuting by public transport, and work/study from home were associated with symptom improvement.Conclusions: The COVID‐19 pandemic negatively affected FD/IBS subjects, with respondents showing FD–IBS overlap syndrome as the most important independent factor associated with deterioration in gastrointestinal symptoms. Physicians need to take extra care of FD/IBS patients in the post‐COVID period.