Background/Aims: We aim to evaluate the differences in the microbiome of responders and non-responders, as well as predict the response to probiotic therapy, based on fecal microbiome data in patients with diarrhea-predominant irritable bowel syndrome (IBS-D). Methods: A multi-strain probiotics that contains Lactobacillus acidophilus (KCTC 11906BP), Lactobacillus plantarum (KCTC11867BP), Lactobacillus rhamnosus (KCTC 11868BP), Bifidobacterium breve (KCTC 11858BP), Bifidobacterium lactis (KCTC 11903BP), Bifidobacterium longum (KCTC 11860BP), and Streptococcus thermophilus (KCTC 11870BP) were used. Patients were categorized into probiotic and placebo groups, and fecal samples were collected from all patients before and at the end of 8 weeks of treatment. The probiotic group was further divided into responders and non-responders. Responders were defined as patients who experienced adequate relief of overall irritable bowel syndrome symptoms after probiotic therapy. Fecal microbiota were investigated using Illumina MiSeq and analyzed using the EzBioCloud 16S database and microbiome pipeline (https://www.EZbiocloud.net). Results: There was no significant difference in the alpha and beta diversity between the responder and non-responder groups. The abundances of the phylum Proteobacteria and genus Bacteroides significantly decreased after probiotic treatment. Bifidobacterium bifidum, Pediococcus acidilactici, and Enterococcus faecium showed a significantly higher abundance in the probiotic group after treatment compared to the placebo group. Enterococcus faecalis and Lactococcus lactis were identified as biomarkers of non-response to probiotics. The abundance of Fusicatenibacter saccharivorans significantly increased in the responders after treatment. Conclusions Probiotic treatment changes some composition of fecal bacteria in patients with IBS-D. E. faecalis and L. lactis may be prediction biomarkers for non-response to probiotics. Increased abundance of F. sccharivorans is correlated to symptom improvement by probiotics in patients with IBS-D.

Background/Aims: Constipation is a common gastrointestinal problem in the elderly. Because of the limitations of life style modifications and the comorbidity, laxative use is also very common. Therefore, this study reviews the latest literature on the effect and safety of laxative in the elderly. Methods: A systematic review of randomized controlled trials investigating the effectiveness and safety of laxatives for constipation in elderly patients over 65 years old were performed using the following databases: PubMed, EMBASE, and the Cochrane Library. Results: Twenty-three randomized controlled trials were included in this review. Among the selected studies, 9 studies compared laxative with placebo and 5 studies compared laxatives of the same type. Four studies compared different types of laxatives or compared combination agents. Five studies compared novel medications such as prucalopride, lubiprostone, and elobixibat with placebo.Psyllium, calcium polycarbophil, lactulose syrup, lactitol, polyethylene glycol, magnesium hydroxide, stimulant laxative with or without fiber, and other medications were more effective than placebo in elderly constipation patients in short-term. Generally, the frequency and severity of adverse effects of laxative were similar between the arms of studies. Conclusions Bulk laxative, osmotic laxative, stimulant laxative with or without fiber, and other medications can be used in elderly patients in short-term within 3 months with reasonable safety. However, the quality of included studies was not high and most of studies was conducted in a small number of patients. Among these laxatives, polyethylene glycol seems to be safe and effective in long-term use of about 6 months in elderly patients.

Background/Aims: Constipation is a common gastrointestinal problem in the elderly. Because of the limitations of life style modifications and the comorbidity, laxative use is also very common. Therefore, this study reviews the latest literature on the effect and safety of laxative in the elderly. Methods: A systematic review of randomized controlled trials investigating the effectiveness and safety of laxatives for constipation in elderly patients over 65 years old were performed using the following databases: PubMed, EMBASE, and the Cochrane Library. Results: Twenty-three randomized controlled trials were included in this review. Among the selected studies, 9 studies compared laxative with placebo and 5 studies compared laxatives of the same type. Four studies compared different types of laxatives or compared combination agents. Five studies compared novel medications such as prucalopride, lubiprostone, and elobixibat with placebo.Psyllium, calcium polycarbophil, lactulose syrup, lactitol, polyethylene glycol, magnesium hydroxide, stimulant laxative with or without fiber, and other medications were more effective than placebo in elderly constipation patients in short-term. Generally, the frequency and severity of adverse effects of laxative were similar between the arms of studies. Conclusions Bulk laxative, osmotic laxative, stimulant laxative with or without fiber, and other medications can be used in elderly patients in short-term within 3 months with reasonable safety. However, the quality of included studies was not high and most of studies was conducted in a small number of patients. Among these laxatives, polyethylene glycol seems to be safe and effective in long-term use of about 6 months in elderly patients.

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the “proven GERD” with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett’s mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis.Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the “proven GERD” with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett’s mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis.Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.