Efficacy and safety of oral lubiprostone in constipated patients with or without irritable bowel syndrome: a randomized, placebo-controlled and dose-finding study

Nocebo effects and influencing factors in the randomized clinical trials of chronic constipation: A systematic review and meta-analysis

BACKGROUND

Nocebo effects are unavoidable in randomized clinical trials. We aimed to assess the magnitude of nocebo effects and explore the influencing factors in chronic constipation.

METHODS

We searched the PubMed, Embase, and Cochrane Library databases up to July 2022. Randomized, placebo-controlled trials investigating interventions in chronic constipation were included. We conducted a random effects meta-analysis of the proportion of adverse events (AEs) in placebo-treated participants and evaluated the effect of trial characteristics on nocebo effects.

KEY RESULTS

We identified 20,204 studies from the databases, of which 61 were included in the final analysis. The pooled placebo AE rate was 30.41%, and AE-related withdrawal rate was 1.53%. The most commonly reported AEs were headache (5.67%), diarrhea (4.45%), abdominal pain (3.98%), nasopharyngitis (3.39%), nausea (3.36%), and flatulence (2.95%). The placebo AE rate was lower in trials conducted in Asia compared to those in Europe, North America, and international trials. It was also lower in trials diagnosed by Rome III compared to clinician's opinion and Rome II. Additionally, the placebo AE rate was lower in single-center trials compared to multicenter trials, lower in 5-8 weeks therapy compared to 9-12 weeks therapy, lower in participants with FC compared to those with IBS-C and CC, lower in trials with 2 arms compared to 3 arms, and higher in trials with prokinetic drugs compared to secretagogues and laxatives.

CONCLUSIONS & INFERENCES

The placebo AE rate was 30.41% in patients with chronic constipation. Based on our findings, we recommend that researchers take the nocebo effects into consideration when designing and conducting clinical trials and adopt specific measures to mitigate the negative influence of nocebo effects.

Comparative profiles of lubiprostone, linaclotide, and elobixibat for chronic constipation: a systematic literature review with meta-analysis and number needed to treat/harm

OBJECTIVE

To comprehensively evaluate the efficacy, safety, patient symptoms, and quality-of-life (QoL) of lubiprostone, linaclotide, and elobixibat as treatment for chronic constipation (CC).

DESIGN

Systematic literature review (SLR) and meta-analysis (MA). Literature searches were conducted on PubMed and Embase using the Ovid platform.

METHODS

SLR including randomized controlled trials (RCTs) and observational studies was conducted to identify the overall efficacy and safety of lubiprostone, linaclotide, and elobixibat. Thereafter, MA was performed using only RCTs. The number needed to treat (NNT) and number needed to harm (NNH) analyses were additionally conducted.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was efficacy regarding change in spontaneous bowel movements. Secondary outcomes included safety, constipation-related symptoms, and QoL.

RESULTS

Twenty-four studies met the inclusion criteria for the SLR: 17 RCTs, 4 observational studies, and 3 single-arm trials. Feasibility assessment for the MA resulted in 14 studies available for safety data analysis, and 8 available for efficacy analysis, respectively. Three drugs showed similar efficacy in the MA and NNT analysis. However, the NNH analysis revealed distinct safety profiles: lubiprostone, linaclotide, and elobixibat were linked to the highest risk of nausea, diarrhea, and abdominal pain, respectively.

CONCLUSION

The current study provides an updated overview of the efficacy, safety, patient symptoms, and QoL of the three drugs with different mechanisms of action for CC treatment.The findings could help physicians adopt an individualized approach for treating patients with CC in clinical practice.

Factors associated with long-term efficacy of lubiprostone for chronic constipation

The prevalence of chronic constipation in Japan is increasing, and is presently almost 1 in 5 people. Because constipation is common, especially in older patients, to avoid adverse events and polypharmacy, simple treatments at low doses are generally desired. Although the chloride channel activator lubiprostone is candidate drug that may solve these problems, factors associated with the long-term efficacy of lubiprostone monotherapy for chronic constipation in treatment-naive patients remain unclear. We here retrospectively investigated the clinical characteristics and factors of patients who achieved long-term constipation improvement with lubiprostone monotherapy. Seventy-four patients with chronic constipation treated with lubiprostone monotherapy (24 or 48 μg/day) from January 2017 to August 2018 were reviewed. Patient characteristics and clinical time-courses were compared between those who sustained improvement for 6 months, and those who became refractory to treatment. In 54 patients (76.1%), constipation improved by lubiprostone administration for 6 months. On multivariate analysis, a significant clinical factor associated with sustained improvement was a starting lubiprostone dose of 24 μg/day (odds ratio: 5.791; 95% confidence interval: 1.032-32.498; p = 0.046). A starting lubiprostone dose of 24 μg/day has efficacy to improve chronic constipation and to prevent adverse events of nausea and diarrhea in Japanese patients.

Analysis of the impact on efficacy of lubiprostone dose reduction to manage adverse events in the treatment of chronic constipation in Japan

OBJECTIVE

To compare outcomes between two doses of lubiprostone in patients with chronic constipation (CC), to assess whether dose reduction affects efficacy.

METHODS

This open-label exploratory study involved 146 patients with CC treated initially with lubiprostone 24 mcg twice daily for a planned duration of 4 weeks. Patients who experienced adverse events (AEs) had their dose reduced to 12 mcg twice daily (for 4 weeks).

RESULTS

Lubiprostone dose was unchanged in 104 patients and reduced due to AEs in 42 patients. Significant differences in the mean number of bowel movements per week favored the dose-reduced group at Week 1 and end of follow-up. No between-group differences were observed over time for mean number of days per week with bowel movements or mean Bristol Stool Form Scale scores. Symptoms of abdominal bloating, strained defecation, and sensation of incomplete evacuation improved in both groups. Before dose reduction, nausea was reported by 64.3% and diarrhea by 45.2% of patients in the dose-reduced group; after dose reduction, no patients reported nausea and one patient reported diarrhea.

CONCLUSION

Dose reduction of lubiprostone reduced the incidence of AEs, with no compromise to efficacy, and may be a suitable approach for patients who develop AEs during treatment.

Characteristics of, and natural history among, individuals with Rome IV functional bowel disorders

BACKGROUND

Little is known about the natural history of functional bowel disorders using Rome IV criteria. We examined these issues in a longitudinal follow-up study.

METHODS

We collected complete demographic, gastrointestinal symptom, and psychological comorbidity data at baseline from 1372 adults who met Rome IV criteria for one of the five functional bowel disorders. At 12 months, we collected data regarding gastrointestinal symptoms, psychological comorbidity, consultation behavior, and treatment commenced. We examined prognosis and stability of all five functional bowel disorders.

KEY RESULTS

At baseline, 811 (59.1%) individuals met Rome IV criteria for irritable bowel syndrome (IBS), 76 (5.5%) functional constipation (FC), 199 (14.5%) functional diarrhea (FDr), 130 (9.5%) functional abdominal bloating or distension (FABD), and 156 (11.4%) unspecified functional bowel disorder (UFBD). In total, 782 (57.0%) were successfully followed up. Individuals with IBS at baseline were significantly more likely to report symptoms compatible with anxiety, depression, or somatoform-type behavior (p < 0.001 for all analyses) at baseline and follow-up compared with those with the other four functional bowel disorders. IBS was the most stable functional bowel disorder; 319 (70.6%) of 452 participants still met criteria for IBS at 12 months, compared with 14 (34.1%) of 41, 43 (35.5%) of 121, 26 (33.8%) of 77, and 37 (40.7%) of 91 for FC, FDr, FABD, and UFBD, respectively (p < 0.001).

CONCLUSIONS AND INFERENCES

Individuals with Rome IV-defined IBS exhibited higher levels of anxiety, depression, or somatoform-type symptom reporting. IBS was the most stable and the likeliest disorder that the other four functional bowel disorders would fluctuate to.

A Systematic Review and Network Meta-Analysis on the Efficacy of Medications in the Treatment of Chronic Idiopathic Constipation in Japan

Background

In the 2010s, medications with new mechanisms were introduced in Japan for the treatment of chronic idiopathic constipation (CIC). A few systematic reviews have compared medications' relative efficacy, but the reviews included studies on patients from various races, even though the mechanism of CIC is considered to differ between races. The aim of this study was to use a systematic review and network meta-analysis to compare the relative efficacy of these medications in Japanese patients.

Methods

We conducted a meta-analysis and report it here according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We identified studies by searching MEDLINE (via the PubMed interface) and the Cochrane Library and ICHUSHI databases and included randomized clinical trials that compared medications for CIC with placebo in Japanese adults. Two reviewers independently screened and assessed articles, abstracted data, and assessed the risk of bias. We pooled data by random-effects meta-analyses and also performed a Bayesian network meta-analysis to indirectly compare data.

Results

The present systematic review and meta-analyses included 1460 patients in 6 randomized clinical trials: 2 on linaclotide, 3 on elobixibat, 2 on lubiprostone, and 1 on lactulose. The results of direct comparisons showed that linaclotide, elobixibat, and lubiprostone were superior to placebo in the change of spontaneous bowel movements (SBMs) within 1 week: linaclotide, 1.95 (95% CI, 1.51-2.39); elobixibat, 5.69 (95% CI, 3.31-8.07); and lubiprostone, 2.41 (95% CI, 0.82-4.01). The Bayesian network meta-analysis showed consistent results. Elobixibat 10 mg was ranked first for the increase in SBMs and complete SBMs within 1 week and the time to first SBM. Lubiprostone 48 μg was ranked first for the proportion of patients with SBM within 24 hours.

Conclusion

Our direct and indirect meta-analyses revealed that the new CIC medications available in Japan have equal efficacy but that elobixibat and lubiprostone are highly likely to be more efficacious.

Efficacy and safety of lubiprostone for the treatment of functional constipation in Chinese adult patients: A multicenter, randomized, double-blind, placebo-controlled trial

OBJECTIVES

Functional constipation is a gastrointestinal disorder prevalent around the world. Lubiprostone is the first locally acting type-2 chloride channel activator to be used for treating constipation. This study aimed to evaluate the efficacy and safety of lubiprostone in Chinese adults with functional constipation.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled study. Patients with functional constipation were randomized to receive either lubiprostone (24 mcg twice daily) or placebo for 4 weeks. The primary end-point was the frequency of spontaneous bowel movements (SBMs) during the first week of treatment. The secondary end-points included the median time of the first SBM, SBM frequency at weeks 2, 3 and 4, weekly response rate of SBMs, the stool consistency score and average number of complete spontaneous bowel movements (CSBMs) per week.

RESULTS

In total, 259 patients were randomized, with 130 in the lubiprostone group and 129 in the placebo group. SBM frequency was higher in the lubiprostone group (4.88 ± 4.09/wk) than that in the placebo group (3.22 ± 2.01/wk) at week 1 (P < 0.0001). SBM frequency was also higher in the lubiprostone group at weeks 2, 3 and 4. The average number of CSBMs and the stool consistency score in the lubiprostone group were significantly higher than that in the placebo group at each week. No drug-related serious adverse events (AEs) occurred. The most commonly reported AE was nausea.

CONCLUSION

Lubiprostone was superior to placebo in treating Chinese patients with functional constipation, together with good safety profile.

Chronic Refractory Constipation in Children: Think Beyond Stools

Chronic refractory constipation (CRC) is defined as children who are unable to pass stools in spite of being on maximum laxative therapy and require daily rectal stimulation in the form of enemas or suppositories to pass stools for >3 months. Children are often referred for treatment of refractory constipation that may result from uncontrolled underlying disease or ineffective treatment. Constipated children can be managed by a variety of medical therapeutic options that yield satisfying results in most cases. However, a subset of constipated children fails to benefit from conventional treatments. On treatment failure or on suspicion of organic disease the patient should be referred for further evaluation. Treatment options for treatment-resistant patients are presented. Pharmalogical and non-pharmalogical treatment modalities are reviewed and an algorithm for refractory constipation in children are presented.

Review article: diagnosis, management and patient perspectives of the spectrum of constipation disorders

BACKGROUND

Chronic constipation is a common, heterogeneous disorder with multiple symptoms and pathophysiological mechanisms. Patients are often referred to a gastroenterology provider after laxatives fail. However, there is limited knowledge of the spectrum and management of constipation disorders.

AIM

To discuss the latest understanding of the spectrum of constipation disorders, tools for identifying a pathophysiologic-based diagnosis in the specialist setting, treatment options and the patient's perspective of constipation.

METHODS

Literature searches were conducted using PubMed for constipation diagnostic criteria, diagnostic tools and approved treatments. The authors provided insight from their own practices.

RESULTS

Clinical assessment, stool diaries and Rome IV diagnostic criteria can facilitate diagnosis, evaluate severity and distinguish between IBS with constipation, chronic idiopathic constipation and dyssynergic defecation. Novel smartphone applications can help track constipation symptoms. Rectal examinations, anorectal manometry and balloon expulsion, assessments of neuromuscular function with colonic transit time and colonic manometry can provide mechanistic understanding of underlying pathophysiology. Treatments include lifestyle and diet changes, biofeedback therapy and pharmacological agents. Several classes of laxatives, as well as prokinetic and prosecretory agents, are available; here we describe their mechanisms of action, efficacy and side effects.

CONCLUSIONS

Constipation includes multiple overlapping subtypes identifiable using detailed history, current diagnostic tools and smartphone applications. Recognition of individual subtype(s) could pave the way for optimal, evidence-based treatments by a gastroenterology provider.

Open-label study to evaluate the treatment continuation rate after a dose reduction of lubiprostone due to onset of adverse events

OBJECTIVE

To investigate the continuation rate with a reduced lubiprostone dose (12 mcg twice daily, BD) after the onset of adverse events (AEs) in patients with chronic constipation (CC).

METHODS

In this exploratory, open-label, multicenter study, patients with CC received lubiprostone 24 mcg BD and the dose was reduced to 12 mcg BD in subjects experiencing AEs. The primary objective was the continuation rate after dose reduction due to nausea/vomiting. Secondary objectives included the continuation rate after dose reduction due to diarrhea/any AE and efficacy, including changes in number of weekly bowel movements and Bristol Stool Form Scale.

RESULTS

Of the 146 patients included in the study, 42 (28.8%) received lubiprostone 12 mcg BD (dose-reduced group) due to any AE. Thirty-six (85.7%) subjects in the dose-reduced group continued treatment and completed the study. 22/27 (81.5%) and 17/19 (89.5%) patients in whom the dose was reduced due to nausea/vomiting or diarrhea, respectively, continued treatment. There was no clinically relevant difference in efficacy after dose reduction.

CONCLUSION

These results suggest that treatment withdrawal due to AEs associated with lubiprostone 24 mcg BD could be minimized in patients with CC after dose reduction to 12 mcg BD, thus resulting in improved long-term outcomes.

CLINICAL TRIAL REGISTRATION

Japan Registry of Clinical Trials (https://jrct.niph.go.jp/latest-detail/jRCTs031180069).

Evidence-based clinical practice guidelines for irritable bowel syndrome 2020

Managing irritable bowel syndrome (IBS) has attracted international attention because single-agent therapy rarely relieves bothersome symptoms for all patients. The Japanese Society of Gastroenterology (JSGE) published the first edition of evidence-based clinical practice guidelines for IBS in 2015. Much more evidence has accumulated since then, and new pharmacological agents and non-pharmacological methods have been developed. Here, we report the second edition of the JSGE-IBS guidelines comprising 41 questions including 12 background questions on epidemiology, pathophysiology, and diagnostic criteria, 26 clinical questions on diagnosis and treatment, and 3 questions on future research. For each question, statements with or without recommendations and/or evidence level are given and updated diagnostic and therapeutic algorithms are provided based on new evidence. Algorithms for diagnosis are requisite for patients with chronic abdominal pain or associated symptoms and/or abnormal bowel movement. Colonoscopy is indicated for patients with one or more alarm symptoms/signs, risk factors, and/or abnormal routine examination results. The diagnosis is based on the Rome IV criteria. Step 1 therapy consists of diet therapy, behavioral modification, and gut-targeted pharmacotherapy for 4 weeks. For non-responders, management proceeds to step 2 therapy, which includes a combination of different mechanistic gut-targeted agents and/or psychopharmacological agents and basic psychotherapy for 4 weeks. Step 3 therapy is for non-responders to step 2 and comprises a combination of gut-targeted pharmacotherapy, psychopharmacological treatments, and/or specific psychotherapy. These updated JSGE-IBS guidelines present best practice strategies for IBS patients in Japan and we believe these core strategies can be useful for IBS diagnosis and treatment globally.

Senna Versus Magnesium Oxide for the Treatment of Chronic Constipation: A Randomized, Placebo-Controlled Trial

INTRODUCTION

This is the first prospective, double-blinded, randomized, placebo-controlled trial to evaluate the safety and efficacy of a stimulant laxative compared with an osmotic agent for the treatment of chronic idiopathic constipation.

METHODS

Patients were randomly administered stimulant laxative (senna, 1.0 g), osmotic agent (magnesium oxide [MgO], 1.5 g), or placebo for 28 consecutive days. The primary endpoint was overall symptom improvement. Secondary endpoints were spontaneous bowel movement (SBM), complete SBM, and patient assessment of constipation quality of life (QOL).

RESULTS

Ninety patients (mean age, 42 years; 93% women; mean duration of symptoms, 9.9 years) were enrolled; all completed the study. The response rate for overall improvement was 11.7% in the placebo group, 69.2% in the senna group, and 68.3% in the MgO group (P < 0.0001). Change in SBM was significantly greater in the senna and MgO groups than that in the placebo group (P < 0.001). Similarly, change in complete SBM was significantly greater in the senna and MgO groups than that in the placebo group (P < 0.01). On the patient assessment of constipation QOL, significant improvements were seen in the senna and MgO groups compared with those in the placebo group (senna, P < 0.05; MgO, P < 0.001). The frequency of severe treatment-related adverse events was 0%.

DISCUSSION

Senna and MgO significantly improved the frequency of bowel movements and QOL score and seem to be effective in the treatment of constipation.

Irritable Bowel Syndrome: Straightening the road from the Rome criteria

A sequence of consensus-based Rome criteria for irritable bowel syndrome (IBS) has been published since 1989. The fundamental definition based on abdominal pain in association with bowel dysfunction has been consistent. However, two major changes occurred in the Rome II and IV criteria. The former change involved "splitting off" of symptoms that were not consistently associated with pain, such as functional, constipation, diarrhea, and bloating. In Rome IV, the main changes were the exclusion of discomfort (in contrast to pain) and the more stringent frequency criteria for the pain to be eligible for diagnosis of IBS (specifically, on average, at least 1 day per week in the last 3 months). Validation studies of the consensus, symptom-based criteria have identified multiple deficiencies that question the rationale for "splitting" the different syndromes, and favor a simpler identification of the classical symptoms of abdominal pain, bowel dysfunction, and bloating, and exclusion of alarm symptoms. Advances in the identification of actionable biomarkers related to the symptoms suggestive of functional gastrointestinal disorders have the potential to usher a change in practice from positive diagnosis of symptom complexes followed by empirical treatment to identification of the mechanisms causing the symptoms and targeted therapy.

Systematic review with meta-analysis: lubiprostone efficacy on the treatment of patients with constipation

BACKGROUND

Lubiprostone is a type 2 chloride channel activator that has been shown to be efficacious and safe in the treatment for chronic constipation.

OBJECTIVE

To systematically review randomized clinical trials (RCTs) assessing efficacy of lubiprostone for patients with chronic idiopathic constipation (CIC), irritable bowel syndrome with predominant constipation (IBS-C) and opioid-induced constipation (OIC).

METHODS

Searches were conducted in PubMed, LILACS, Cochrane Collaboration Database, and Centre for Reviews and Dissemination. Lubiprostone RCTs reporting outcomes of spontaneous bowel movements (SBM) and abdominal pain or discomfort were deemed eligible. Meta-analysis was performed calculating risk ratios and 95% confidence intervals, using the Mantel-Haenszel method and random effects model.

RESULTS

Searches yielded 109 records representing 93 non-duplicate publications, and 11 RCTs (978 CIC, 1,366 IBS-C, 1,300 OIC, total = 3,644) met inclusion criteria. Qualitative synthesis showed that for CIC patients, lubiprostone is superior to placebo in terms of SBM outcomes. Meta-analysis for CIC was feasible for full responder and SBM within 24h rates, indicating superiority of lubiprostone over placebo. For IBS-C, lubiprostone was significantly superior for all SBM outcomes in follow-ups ranging from 1 week-3 months. In terms of abdominal pain, lubiprostone provided significantly better symptoms relief, particularly after 1 month of treatment. For OIC, lubiprostone was more effective than placebo for both SBM and discomfort measures.

CONCLUSION

Our findings demonstrated that lubiprostone is superior to placebo in terms of SBM frequency for CIC, IBS-C and OIC. In terms of abdominal symptoms, the most pronounced effect was seen for abdominal pain in IBS-C patients.

Medications for constipation in 2020

PURPOSE OF REVIEW

Chronic constipation is a common problem that substantially impacts the quality of life of patients and families, healthcare professionals, and resources. The purpose of this review is to discuss the medications that are available for management of chronic constipation, including medications that have been approved by the FDA for adults, other been studied in pediatrics now, and might become available within the upcoming years.

RECENT FINDINGS

Recent developments in the evaluation of childhood constipation are providing a better understanding into defecation disorders in children and not only new therapies are becoming available, including medications, but also other therapies, such as biofeedback for treatment of functional defecation disorders, electrical stimulation, and surgeries. The aim of this article is to provide an update on the medications that are available for management of chronic constipation, especially with the development and study of newer medications, such as Linaclotide and Lubiprostone with promising results in both adult and pediatric patients.

SUMMARY

This review will help us identify and have a better understanding regarding what medications are available for use and the indications, so that we can better manage patients with chronic constipation. VIDEO ABSTRACT.

Lubiprostone in patients with non-alcoholic fatty liver disease: a randomised, double-blind, placebo-controlled, phase 2a trial

BACKGROUND

The laxative drug lubiprostone improves intestinal permeability in healthy volunteers. We aimed to assess efficacy and safety of lubiprostone in patients with non-alcoholic fatty liver disease (NAFLD) with constipation via attenuation of intestinal permeability.

METHODS

This randomised, double-blind, placebo-controlled, phase 2a study in Yokohama City University Hospital, Japan, recruited patients (aged 20-85 years) with NAFLD and constipation, alanine aminotransferase (ALT) at least 40 U/L, liver stiffness (≤6·7 kPa), and hepatic fat fraction at least 5·2% when assessed by MRI-proton density fat fraction. Eligible patients were randomly assigned (11:10:9) by a computer-based system and stratified by age and sex to receive 24 μg lubiprostone, 12 μg lubiprostone, or placebo, orally, once per day for 12 weeks. The primary endpoint was the absolute changes in ALT at 12 weeks. Efficacy analysis was done by intention to treat. Safety was assessed in all treated patients. This trial was registered with University Hospital Medical Information Network Clinical Trials Registry (UMIN000026635).

FINDINGS

Between March 24, 2017, and April 3, 2018, we screened 288 patients, of whom 150 (52%) were randomly assigned to treatment: 55 patients were assigned to receive 24 μg lubiprostone, 50 to receive 12 μg lubiprostone, and 45 to receive placebo. A greater decrease in the absolute ALT levels from baseline to 12 weeks was seen in the 24 μg lubiprostone group (mean -13 U/L [SD 19]) than in the placebo group (1 U/L [24]; mean difference -15 U/L [95% CI -23 to -6], p=0·0007) and in the 12 μg lubiprostone group (-12 U/L [21]) than in the placebo group (mean difference -13 U/L [-22 to -5], p=0·0023). 18 (33%) of 55 patients in the 24 μg group had at least one adverse event, as did three (6%) of 47 patients in the 12 μg group and three (7%) of 43 in the placebo group. The most common adverse event was diarrhoea (17 [31%] of patients in the 24 μg group, three [6%] in the 12 μg group, none in the placebo group). No life-threatening events or treatment-related deaths occurred.

INTERPRETATION

Lubiprostone was well tolerated and reduced the levels of liver enzymes in patients with NAFLD and constipation. Further studies are necessary to better define the efficacy and tolerability of lubiprostone in patients with NAFLD without constipation.

FUNDING

Mylan EPD G.K.

Chronic constipation and abdominal pain: Independent or closely interrelated symptoms?

Constipation is both a symptom and a disorder, seen in both functional constipation and irritable bowel syndrome with constipation predominance (IBS-C). Despite the Rome IV criteria distinguishing between these conditions, they share many therapeutic approaches. This review aims to explore the relationship between constipation and abdominal pain and assess the evidence surrounding whether laxation improves abdominal pain and whether such a response to laxation differs between IBS-C and functional constipation. In patients with functional constipation, increasing frequency of bowel motions by laxatives regardless of mechanism of action is associated with reductions in the severity of abdominal pain, supporting the role of constipation as a contributor to abdominal discomfort. In patients with IBS-C, evidence from systematic reviews indicates that abdominal pain is driven by factors additional to constipation alone and that visceral analgesic modulation is also needed to optimize pain. Changing definitions of IBS-C and heterogeneity in clinical trial design including endpoints have raised uncertainty about the comparative ability of older laxatives without known neuromodulatory effects to improve chronic abdominal pain compared with new secretagogues and prokinetics for the management of IBS-C. While it is known that abdominal pain is associated with constipation and laxation contributes to relief of that pain, it remains unproven whether proposed visceral analgesic properties of new laxatives provide greater pain relief than laxation alone. However, it is likely that the response to laxation in IBS-C is only part of the puzzle.

An update on efficacy and safety considerations for the latest drugs used to treat irritable bowel syndrome

INTRODUCTION

Irritable bowel syndrome (IBS), globally affecting 11.2% of the population and imposing a direct annual cost of $1.7bn-$10bn in the US, is one of the today's major therapeutic challenges. Therefore, there is urgent need to address this issue through reviewing the tolerability and efficacy of available medications.

AREAS COVERED

Over the past decade, related experiments were cited through Clinicaltrials.gov, PubMed, WHO ICTRP, and Cochrane library. Pharmacological parameters of approved medications available in the USFDA, EMA, TGA and PMDA were also stated.

EXPERT OPINION

Anti-spasmodics are used as the first-line treatment in pain-predominant IBS and IBS-D, among which calcium channel blockers and neurokinin-type 2 receptor antagonists seem to replace anti-cholinergic drugs. As second-line treatments, rifaximin is considered to be the best for IBS-D though it has lower efficacy than alosetron and eluxadoline. For IBS-C, linaclotide is the most effective and the safest second-line therapy, following laxatives/fibers, which may be replaced by tenapanor, in the future. When moderate to severe IBS is associated with severe pain or comorbid psychological disorders, gut-brain neuromodulators could also be prescribed. Regarding all this, there is still a paramount need to conduct careful clinical studies on efficacy, safety and cost-effectiveness of current approved and non-approved treatments.

Differences in efficacy and safety of lubiprostone used for idiopathic vs opioid-induced constipation: meta-analysis of East Asian and Western populations

Several secretagogues, such as lubiprostone, have been developed for the treatment of constipation in the last 10 years. It is unclear whether the efficacy of lubiprostone for spontaneous bowel movement (SBM) and the adverse events are similar between idiopathic and opioid-induced constipation and between East-Asian and Western populations. We conducted a meta-analysis to compare efficacy and safety of lubiprostone in two populations with idiopathic vs opioid-induced constipation. The PubMed and Cochrane databases were searched for relevant randomized control trials (RCTs) investigating the efficacy and safety that were published in English up to March 2019. Compared with the placebo groups in idiopathic and opioid-induced constipation, the lubiprostone groups significantly improved in 24-h SBM frequency [relative risk: 1.28, 95% confidence interval, 1.11-1.49, and 1.23, 1.14-1.32] and weekly frequency >3 SBM/week (1.68, 1.41-2.01, and 1.43, 1.01-2.04), respectively. Although the incidence of adverse events was similar between idiopathic and opioid-induced constipation, the incidence of nausea in Western populations with idiopathic constipation was significantly higher (29.2%) than that in East-Asian populations (10.0%, p<0.001). In conclusion, lubiprostone effectively improved SBM frequency, irrespective of the etiology of constipation and population. The incidence of nausea was significantly higher in Western populations.

The Efficacy and Safety of Elobixibat for the Elderly with Chronic Constipation: A Multicenter Retrospective Cohort Study

Materials and Methods

This was a multicenter retrospective cohort study. The subjects were patients aged ≥20 years treated for chronic constipation from May 2018 to November 2019 at 12 related institutions. Patients were divided into ≤74 years and ≥75 years old. Elobixibat at 10 mg/day was prescribed for two weeks. We then analyzed the discontinuation due to ineffectiveness, change of spontaneous bowel movements (SBM), stool consistency, the time until the first SBM, adverse events, and effect-related factors.

Results

There were 140 cases (61 males) evaluated, with an average age of 72.1 ± 13.6 years (≤74 years: 71 cases; ≥75 years: 69 cases). The discontinuation rate was 7.9%. The SBM (times/week) increased from 2.86 to 6.08 (p < 0.001). The overall SBM improvement rate was 74.0% (≤74 years: 78.2% vs. ≥75 years: 68.9%, p = 0.31; male: 75.0% vs. female: 73.3%, p = 0.78). The overall improvement rate of stool consistency was 59.6% (≤74 years: 62.9%, ≥75 years: 56.1%, p = 0.42). The time until the first SBM (hours) for those ≤74 years and ≥75 years was 17.2 ± 14.3 and 11.2 ± 8.4 (p = 0.04). Adverse event rates for those ≤74 years and ≥75 years were 28.2% and 10.1% (p < 0.01). There were no significant effect-related factors for gender, age, and use of laxatives.

Conclusions

Short-period elobixibat is shown to be effective also for the elderly and male.

A Randomized Double-blind Placebo-controlled Trial on the Effect of Magnesium Oxide in Patients With Chronic Constipation

Background/Aims

Magnesium oxide (MgO) has been frequently used as a treatment for chronic constipation (CC) since the 1980s in Japan. The aim of this study is to evaluate its therapeutic effects of MgO in Japanese CC patients.

Methods

We conducted a randomized, double-blind placebo-controlled study. Thirty-four female patients with mild to moderate constipation were randomly assigned to either placebo (n = 17) or MgO group (n = 17) 0.5 g × 3/day for 28 days. Primary endpoint was overall improvement over the 4-week study period. Secondary endpoints were changes from baseline in spontaneous bowel movement (SBM), response rates of complete spontaneous bowel movement (CSBM), stool form, colonic transit time (CTT), abdominal symptom, and quality of life.

Results

One patient failed to complete the medication regimen and was omitted from analysis: data from 16 placebo and 17 MgO patients were analyzed. The primary endpoint was met by 25.0% of placebo vs 70.6% of MgO group (P = 0.015). MgO significantly improved SBM changes compared to placebo (P = 0.002). However, MgO did not significantly improved response rates of CSBM compared to placebo (P = 0.76). In addition, MgO significantly improved Bristol stool form scale changes (P < 0.001) and significantly improved CTT compared to the placebo group (P < 0.001). MgO significantly improved the Japanese version of the patient assessment of constipation quality of life (P = 0.003).

Conclusion

Our placebo-controlled study demonstrated that MgO was effective treatment for improving defecation status and shortened CTT in Japanese CC patients with mild to moderate symptoms.

Second Asian Consensus on Irritable Bowel Syndrome

BACKGROUND/AIMS

There has been major progress in our understanding of the irritable bowel syndrome (IBS), and novel treatment classes have emerged. The Rome IV guidelines were published in 2016 and together with the growing body of Asian data on IBS, we felt it is timely to update the Asian IBS Consensus.

METHODS

Key opinion leaders from Asian countries were organized into 4 teams to review 4 themes: symptoms and epidemiology, pathophysiology, diagnosis and investigations, and lifestyle modifications and treatments. The consensus development process was carried out by using a modified Delphi method.

RESULTS

Thirty-seven statements were developed. Asian data substantiate the current global viewpoint that IBS is a disorder of gut-brain interaction. Socio-cultural and environmental factors in Asia appear to influence the greater overlap between IBS and upper gastrointestinal symptoms. New classes of treatments comprising low fermentable oligo-, di-, monosacharides, and polyols diet, probiotics, non-absorbable antibiotics, and secretagogues have good evidence base for their efficacy.

CONCLUSIONS

Our consensus is that all patients with functional gastrointestinal disorders should be evaluated comprehensively with a view to holistic management. Physicians should be encouraged to take a positive attitude to the treatment outcomes for IBS patients.

Lubiprostone in the treatment of chronic idiopathic constipation: an update on health-related quality of life and patient-reported outcomes

Chronic idiopathic constipation, if inadequately treated, can be bothersome with a detrimental effect on patients’ quality of life (QOL). This may also result in frequent health care visits, increasing the burden of this ailment’s medical cost. Management strategies, focused on lifestyle changes, include increased exercise, a high-fiber diet, and toilet training. Pharmacologic options include fiber supplementation, laxatives, serotonergic agents, and prosecretory agents such as lubiprostone. In this review, we were able to conclude that lubiprostone, when used for chronic idiopathic constipation, has a significantly beneficial effect on both patients’ symptoms and their QOL. In multiple randomized controlled trials, it has been found to have increased the number of spontaneous bowel movements at different time endpoints. Corresponding improvements were also observed for abdominal bloating, discomfort, stool frequency, and straining symptoms among patients.

Laxative Effects of Taurine on Loperamide-Induced Constipation in Rats

In the present study, we investigated the laxative effects of taurine in a rat model of loperamide-induced constipation. Rats were divided into six groups of six animals each: normal (NOR), control (CON), loperamide + Dulcolax (5.5 mg/kg, p.o.), and loperamide + various doses of taurine (7.5, 15, and 30 mg/kg, p.o.). Laxative activity was determined based on body weight, feeding characteristics, fecal properties, gastrointestinal transit (GIT) ratio, and the levels of serum gastrointestinal hormones. Taurine supplementation significantly increased the number, wet weight, and water content of fecal pellets in rats with loperamide-induced constipation. GIT ratio and loperamide-induced serum metabolic parameters, such as gastrin (GAS), motilin (MTL), and somatostatin (SS) significantly changed after supplementation with taurine in loperamide-induced constipated rats. We suggest that taurine had a potent effect against loperamide-induced constipation in part by increasing gastrointestinal motility.

Experimental Paradigm for the Assessment of the Non-pharmacological Mechanism of Action in Medical Device Classification: The Example of Glycerine as Laxative

The evolution of medical devices has led to the introduction of medical devices that include "substances" and which, due to their presentation and sites of application may resemble medicinal products. The difference between substance-based medical devices and medicinal products lies in the proper definition of the principal mechanism of action. The major problem at the moment is the lack of a proper procedure for the demonstration of a mechanism that is "not pharmacological, immunological or metabolic." We aimed to design an experimental set up to demonstrate the difference between the mechanism of action of two substances used commonly for the treatment of constipation, lubiprostone (example of medicinal product) and glycerine (example of medical device). By implementing cellular models and molecular analyses we demonstrate the difference in their mechanism of action. This set up can be considered an example on the possibility to define a paradigm for the case by case study of the mechanism of action of substances and combination of substances in medical devices.

Dose-finding study of linaclotide in Japanese patients with chronic constipation: A phase II randomized, double-blind, and placebo-controlled study

BACKGROUND

Based on the previous phase II/III studies of irritable bowel syndrome with constipation (IBS-C) in Japan that demonstrated the efficacy and safety of linaclotide 0.5 mg/d, we evaluated linaclotide at doses of 0.5 mg/d and lower in the treatment of Japanese patients with chronic constipation (CC).

METHODS

This was a phase II randomized, double-blind, placebo-controlled, dose-finding study of linaclotide for Japanese patients with CC (n = 382, 64 men, 318 women, age 20-75). After a baseline period of two weeks, patients were randomized to receive placebo (n = 80), or 0.0625 mg (n = 82), 0.125 mg (n = 71), 0.25 mg (n = 73) or 0.5 mg (n = 76) of linaclotide during a two-week treatment period. The primary efficacy endpoint was change from baseline in weekly spontaneous bowel movement (SBM) frequency during the first week. Secondary endpoints included complete SBM (CSBM) responder rates and IBS-QOL. Safety and adverse events were also evaluated.

KEY RESULTS

The change in SBM frequency during the first week (mean) was 3.89, 3.11, 3.87, and 3.85 for 0.0625 mg, 0.125 mg, 0.25 mg, and 0.5 mg for linaclotide, significantly higher than for placebo (1.91, P < 0.05). The CSBM responder, which is an important parameter, showed the greatest improvement at the 0.5 mg during the 2 week. The most frequent adverse event in the linaclotide groups was diarrhea.

CONCLUSIONS & INFERENCES

Our results suggest that 0.0625, 0.125, 0.25, and 0.5 mg/d are effective doses of linaclotide for treating CC in Japanese patients. ClinicalTrials.gov: NCT02425722, supported by Astellas Pharma, Inc.

EFFICACY AND SAFETY OF INTESTINAL SECRETAGOGUES FOR CHRONIC CONSTIPATION: A SYSTEMATIC REVIEW AND META-ANALYSIS

BACKGROUND

Intestinal secretagogues have been tested for the treatment of chronic constipation and constipation-predominant irritable bowel syndrome. The class-effect of these type of drugs has not been studied.

OBJECTIVE

To determine the efficacy and safety of intestinal secretagogues for the treatment of chronic constipation and constipation-predominant irritable bowel syndrome.

METHODS

A computer-based search of papers from 1966 to September 2017 was performed. Search strategy consisted of the following MESH terms: intestinal secretagogues OR linaclotide OR lubiprostone OR plecanatide OR tenapanor OR chloride channel AND chronic constipation OR irritable bowel syndrome. Data were extracted as intention-to-treat analyses. A random-effects model was used to give a more conservative estimate of the effect of individual therapies, allowing for any heterogeneity among studies. Outcome measures were described as Relative Risk of achieving an improvement in the symptom under consideration.

RESULTS

Database Search yielded 520 bibliographic citations: 16 trials were included for analysis, which enrolled 7658 patients. Twelve trials assessed the efficacy of intestinal secretagogues for chronic constipation. These were better than placebo at achieving an increase in the number of complete spontaneous bowel movements per week [RR 1.87 (1.24-2.83)], at achieving three or more spontaneous bowel movements per week [RR 1.56 (1.31-1.85)] and at inducing spontaneous bowel movement after medication intake [RR 1.49 (1.07-2.06)]. Similar results were observed when assessing the efficacy of intestinal secretagogues on constipation-predominant irritable bowel syndrome based on the results of six trials.

CONCLUSION

Intestinal secretagogues are useful and safe therapeutic alternatives for the treatment of constipation-related syndromes.

Guidelines on the management of irritable bowel syndrome: In memory of Professor Witold Bartnik

These guidelines constitute an update of the previous "Recommendations on the management of irritable bowel syndrome" issued in 2008. They have been developed by a Task Force organized by the Governing Board of the Polish Society of Gastroenterology. They discuss, with particular emphasis on new scientific data covering papers published since 2008, the aetiology, epidemiology, clinical presentation, diagnostic principles and criteria for the diagnosis, and recommendations for the treatment of irritable bowel syndrome (IBS). The English-language acronym for the syndrome (IBS) has become popular in medical and popular scientific language. It is also widely recognized by patients who identify with this diagnosis. Therefore, in the discussed guidelines, this is what we will use.

Bowel Dysfunction in Spinal Cord Injury

PURPOSE OF REVIEW

To evaluate and report current evidence regarding the management of bowel dysfunction in spinal cord injury. There is a paucity of high-quality large studies on which to base management advice.

RECENT FINDINGS

Recent research has focused on defining the nature of symptomatology of bowel dysfunction in SCI and describing the effects on quality of life and social interactions. Technical aspects of colonoscopy have received attention, and aspects of understanding the pathophysiology in relation to both neural and non-neural dysfunction have been studied. There has been refinement and expansion of the pharmacological and non-pharmacological treatment options for bowel dysfunction in SCI. Management of bowel dysfunction in SCI requires a comprehensive and individualized approach, encompassing lifestyle, toileting routine, stimulation, diet, medications, and surgery. Further high-quality research is required to inform best practice.

Chronic abdominal pain in irritable bowel syndrome - current and future therapies

INTRODUCTION

Irritable bowel syndrome (IBS) is a functional gut disorder that typically manifests in early adult years. One of the two major symptoms of the disease is chronic, visceral pain. The patients report pain as the most distressing symptom with the greatest impact on quality of life, challenging both to patients and healthcare providers. Areas covered: This review focuses on the pathophysiology of abdominal pain in IBS and describes current treatment possibilities. It also covers latest findings that may lead to novel pharmacological options in IBS pain management. Expert commentary: Pain is the main contributor to severity in IBS. Seeking pain alleviation is the most common reason that IBS sufferers consult with their physicians. Not all patients report being satisfied with available treatments for pain in IBS and there is a pressing need to find new, more efficient therapies for this syndrome.

Efficacy, safety, and tolerability of lubiprostone for the treatment of non-alcoholic fatty liver disease in adult patients with constipation: The LUBIPRONE, double-blind, randomised, placebo-controlled study design

BACKGROUND

This paper reports the protocol of a randomised, double-blind, placebo-controlled study to test the efficacy, safety, and tolerability of lubiprostone (LUB) vs. placebo on suppressing gut permeability in non-alcoholic fatty liver disease (NAFLD) patients with constipation. NAFLD, including non-alcoholic steatohepatitis (NASH), is a common chronic liver disorder. Progression is associated with increased gut permeability and gut-derived endotoxins. Most NAFLD/NASH clinical trial drugs aim to improve liver function or systemic metabolism. LUB is a type 2 chloride channel activator used as a laxative for the treatment of patients with constipation. LUB suppresses gut permeability induced by non-steroidal anti-inflammatory drugs in healthy volunteers and lowers blood endotoxin levels. There have been no clinical studies of LUB for NAFLD/NASH patients.

METHODS

The study plans to enrol adult patients (20-85 years, planned enrolment, n = 150; planned sample size, n = 120) with NAFLD and constipation, alanine aminotransferase ≥40 IU/L, equivalent steatosis grade ≥1, and equivalent fibrosis stage <4 measured using non-invasive vibration-controlled transient elastography and magnetic resonance imaging. Participants will be randomly allocated into three groups: LUB 12 μg, LUB 24 μg, and a placebo group.

RESULTS

The primary endpoint will be changes in alanine aminotransferase from baseline at 12 weeks. The main secondary endpoint will be changes in intestinal permeability from baseline at 12 weeks using the lactulose mannitol ratio.

CONCLUSIONS

This study will determine whether LUB improves gut permeability in NAFLD patients with constipation.

TRIAL REGISTRATION

This trial is registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN000026635).

The combination of Cassia obtusifolia L. and Foeniculum vulgare M. exhibits a laxative effect on loperamide-induced constipation of rats

Chronic constipation is a functional gastrointestinal disease that is detrimental to the quality of patient life. Cassia obtusifolia L. (CO) and Foeniculum vulgare M. (FV) are commonly used as medicinal foods in many countries. We aimed to examine the laxative effect and their underlying mechanism of CO and FV mixture on loperamide (lop)-induced constipated rats. To determine the laxative effects of these compounds, Sprague-Dawley rats were divided into six groups: the control, lop-induced constipated (2mg/kg), and three doses (100, 300, and 500mg/kg) of CO and FV mixture-, and Bisacodyl (bis, 3.3mg/kg)-treated groups. The mixture of CO and FV and bis were orally administered once a day for 4 weeks. For induction of constipation, the lop were treated with a dose of 2 mg/kg twice a day on the 3^rd week after treatments of CO and FV extracts and bis. The results were revealed that the CO and FV mixture has the laxative effects more than those in CO and FV-alone treatments on constipated rats by determining the stool parameters, including stool number and weight. Indeed, stool parameters, such as, stool number, weight, and water contents and colonic peristalsis from the intestinal transit length and ratio were dramatically improved by CO and FV mixture treatment. Histological study also revealed that CO and FV mixture enhanced the thicknesses of mucosa and muscular layers of the colon in constipated rats. For their underlying mechanism, the mRNAs and proteins expression of muscarinic acetylcholine receptors (mAchR) M2 and M3 and their downstream signaling were preserved by CO and FV mixture treatment in constipated rats. Therefore, this study suggests that treatment with CO and FV mixture has beneficial effects against constipation. We further suggest that CO and FV mixture may be utilized as an alternative therapeutic strategy for constipation.

Absorption, disposition, metabolism and excretion of [14C]mizagliflozin, a novel selective SGLT1 inhibitor, in rats

The pharmacokinetic and metabolite profiles of mizagliflozin, a novel selective sodium glucose co-transporter 1 inhibitor designed to act only in the intestine, were investigated in rats. Mizagliflozin administrated intravenously (0.3 mg/kg) and orally (3 mg/kg) declined with a short half-life (0.23 and 1.14 h, respectively). The absolute bioavailability was only 0.02%. Following intravenous administration of [¹⁴C]mizagliflozin (0.3 mg/kg), radioactivity in plasma was also rapidly declined. Up to 24 h after oral administration of [¹⁴C]mizagliflozin (1 mg/kg), radioactivity was recovered in the faeces (98.4%) and in the urine (0.8%). No remarkable accumulation of radioactivity in tissues was observed using tissue dissection technique and whole body autoradiography. Orally dosed [¹⁴C]mizagliflozin was mostly metabolised to its aglycone, KP232, in the intestine. In the plasma, KP232 and its glucuronide were predominant. KP232 glucuronide was also prominent in the bile and was recovered as KP232 in the faeces possibly because of the deconjugation by gut microflora. Mizagliflozin was observed neither in the urine nor the faeces. These findings suggest that orally administered mizagliflozin is poorly absorbed, contributing to low systemic exposure; if absorbed, mizagliflozin is rapidly cleared from circulation.

Irritable bowel syndrome in Asia: Pathogenesis, natural history, epidemiology, and management

Historically, the epidemiology of gastrointestinal diseases in Asia was different from that in Western countries. Early studies suggested a low prevalence of irritable bowel syndrome (IBS) in Asia. As the diagnosis of IBS is symptom-based and as symptom perception, expression, and interpretation are influenced by sociocultural perspectives including language, the presentation of IBS is expected to vary in different communities. Furthermore, the pathogenesis is multifactorial with psychosocial (stress, illness, behavior, and diet) and biological (infection, gut microbiota, and immune activation) variables interacting, and so, the present study can anticipate that the development of IBS will vary in different environments. In recognition of this aspect of functional gastrointestinal disorders, the recently published Rome IV documents have provided greater focus on cross-cultural factors. In this review, the present study seeks to highlight Asian perspectives by identifying historical trends and recent publications from the region and comparing these with the observations from Western societies.

Lubiprostone improves intestinal permeability in humans, a novel therapy for the leaky gut: A prospective randomized pilot study in healthy volunteers

BACKGROUND AND AIMS

The barrier function of the small intestinal mucosa prevents the introduction of undesired pathogens into the body. Breakdown of this barrier function increases intestinal permeability. This has been proposed to induce not only gastrointestinal diseases, including inflammatory bowel disease and irritable bowel syndrome, but also various other diseases, including allergies, diabetes mellitus, liver diseases, and collagen diseases, which are associated with this so called "leaky gut syndrome." As such, a method to prevent leaky gut syndrome would have substantial clinical value. However, no drugs have been demonstrated to improve disturbed intestinal permeability in humans to date. Therefore, we investigated whether a drug used to treat chronic constipation, lubiprostone, was effective for this purpose.

METHODS

Healthy male volunteers were treated with lubiprostone (24 μg/day) for 28 days. Intestinal permeability was evaluated by measuring the lactulose-mannitol ratio (LMR) after administration of diclofenac and compared with an untreated group. The examination was conducted three times in total, i.e., at baseline before diclofenac administration and after 14 and 28 days of lubiprostone treatment. Blood endotoxin activity was also evaluated at the same time points.

RESULTS

The final analysis was conducted on 28 subjects (14 in the lubiprostone group and 14 in the untreated group). The LMR after 28 days of treatment was significantly lower in the lubiprostone group than that in the untreated group (0.017 vs. 0.028, respectively; 95% confidence interval, -0.022--0.0001; p = 0.049). Blood endotoxin activity exhibited almost no change over time in the lubiprostone and untreated groups and displayed no significant differences at any time point of examination.

CONCLUSIONS

This study is the first to report an improvement in leaky gut using an available drug in humans. The result suggests that lubiprostone may prevent and ameliorate "leaky gut syndrome". However, a pivotal trial is needed to confirm our finding.

Childhood constipation: finally something is moving!

Recent developments in the evaluation and treatment of childhood constipation are likely to influence the way we deal with pediatric defecation disorders in the near future. Innovations in both colonic and anorectal manometry are leading to novel insights into functional defecation disorders in children. Promising results have been achieved with innovative therapies such as electrical stimulation and new drugs with targets that differ from conventional pharmacological treatments. Also, new surgical approaches, guided by manometric findings, have led to improvement in patient outcome. Finally, utilization of non-pharmacological interventions such as fiber and probiotics has been a field of particular interest in recent years. The aim of this article is to provide an update on these and other novel diagnostic and therapeutic tools related to childhood constipation.

Guidelines for the Diagnosis and Treatment of Chronic Functional Constipation in Korea, 2015 Revised Edition

The Korean Society of Neurogastroenterology and Motility first published guidelines for chronic constipation in 2005 and was updated in 2011. Although the guidelines were updated using evidence-based process, they lacked multidisciplinary participation and did not include a diagnostic approach for chronic constipation. This article includes guidelines for diagnosis and treatment of chronic constipation to realistically fit the situation in Korea and to be applicable to clinical practice. The guideline development was based upon the adaptation method because research evidence was limited in Korea, and an organized multidisciplinary group carried out systematical literature review and series of evidence-based evaluations. Six guidelines were selected using the Appraisal of Guidelines for Research & Evaluation (AGREE) II process. A total 37 recommendations were adopted, including 4 concerning the definition and risk factors of chronic constipation, 8 regarding diagnoses, and 25 regarding treatments. The guidelines are intended to help primary physicians and general health professionals in clinical practice in Korea, to provide the principles of medical treatment to medical students, residents, and other healthcare professionals, and to help patients for choosing medical services based on the information. These guidelines will be updated and revised periodically to reflect new diagnostic and therapeutic methods.

Persistent constipation and abdominal adverse events with newer treatments for constipation

Background

Clinical trials of several new treatments for opioid-induced constipation (OIC), chronic idiopathic constipation (CIC) and constipation-predominant irritable bowel syndrome (IBS-C) have focused on differences between subjects relieved of constipation with placebo and active treatment. Patients and clinicians however, are more interested in the probability these treatments provide actual relief of constipation and its associated symptoms.

Methods

We searched the medical literature using MEDLINE and Cochrane central register of controlled trials. Randomised, placebo-controlled trials that examined the use of methylnaltrexone, naloxegol, lubiprostone, prucalopride or linaclotide in adults with OIC, CIC and IBS-C were eligible for inclusion. The primary efficacy measure was relief of constipation. Adverse event data for abdominal symptoms were also analysed.

Key results and findings

25 publications were included in our analyses. The proportion of constipated individuals with active treatment was significantly lower than the proportion with placebo; however, in 15 of these 20 trials analysed, a majority of patients remained constipated with active treatment. Analyses of adverse event data revealed that the percentage of participants who experienced abdominal pain, diarrhoea and flatulence with active treatment was higher than that with placebo in the majority of trials analysed.

Conclusions

Newer pharmacological treatments for constipation are superior to placebo in relieving constipation, but many patients receiving active treatment may remain constipated. In addition, all 5 of the treatments studied are accompanied by no change or a possible increase in the prevalence of abdominal symptoms, such as abdominal pain, diarrhoea and flatulence.

Lubiprostone Is Effective in the Treatment of Chronic Idiopathic Constipation and Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To evaluate the efficacy and safety of lubiprostone in the treatment of chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C).

PATIENTS AND METHODS

We performed a literature search of the MEDLINE, Cochrane, Google Scholar, and ClinicalTrials.gov databases (from January 1, 2005, through January 31, 2015). Relevant studies meeting the inclusion criteria were manually searched by 2 independent reviewers. Efficacy outcomes evaluated at 1 week, 1 month, and 3 months of intervention were weekly frequency of spontaneous bowel movements, severity of constipation, consistency of stools, degree of abdominal pain/discomfort, degree of straining, and abdominal bloating.

RESULTS

Of 246 studies identified, data from 9 trials comprising 1468 patients (63.6%) in the lubiprostone group and 841 (36.4%) in the placebo group were analyzed. We found that lubiprostone treatment significantly improved the severity of constipation, stool consistency, abdominal pain, degree of straining, and abdominal bloating at 1 week (P≤.03) and 1 month (P≤.004), except for abdominal pain at 1 month, which was similar to that when treated with placebo (P=.21). At 3 months, except for abdominal bloating (P=.03), there was no difference between lubiprostone and placebo groups in all other outcomes (P≥.05). Adverse effects such as nausea, vomiting, and diarrhea were common (incidence rate, 2.4%-75%); however, the incidence of serious adverse effects was low (<5%) and was mostly unrelated to lubiprostone treatment.

CONCLUSION

Lubiprostone is a safe and efficacious drug for the treatment of chronic idiopathic constipation and irritable bowel syndrome with constipation, with limited adverse effects in 3 months of follow-up.

Irritable bowel syndrome

Irritable bowel syndrome (IBS) is a functional gastrointestinal disease with a high population prevalence. The disorder can be debilitating in some patients, whereas others may have mild or moderate symptoms. The most important single risk factors are female sex, younger age and preceding gastrointestinal infections. Clinical symptoms of IBS include abdominal pain or discomfort, stool irregularities and bloating, as well as other somatic, visceral and psychiatric comorbidities. Currently, the diagnosis of IBS is based on symptoms and the exclusion of other organic diseases, and therapy includes drug treatment of the predominant symptoms, nutrition and psychotherapy. Although the underlying pathogenesis is far from understood, aetiological factors include increased epithelial hyperpermeability, dysbiosis, inflammation, visceral hypersensitivity, epigenetics and genetics, and altered brain-gut interactions. IBS considerably affects quality of life and imposes a profound burden on patients, physicians and the health-care system. The past decade has seen remarkable progress in our understanding of functional bowel disorders such as IBS that will be summarized in this Primer.

Pharmacological, Pharmacokinetic, and Pharmacogenomic Aspects of Functional Gastrointestinal Disorders

This article reviews medications commonly used for the treatment of patients with functional gastrointestinal disorders. Specifically, we review the animal models that have been validated for the study of drug effects on sensation and motility; the preclinical pharmacology, pharmacokinetics, and toxicology usually required for introduction of new drugs; the biomarkers that are validated for studies of sensation and motility endpoints with experimental medications in humans; the pharmacogenomics applied to these medications and their relevance to the FGIDs; and the pharmacology of agents that are applied or have potential for the treatment of FGIDs, including psychopharmacologic drugs.

Lubiprostone in constipation: clinical evidence and place in therapy

Constipation is one of the most common function bowel disorders encountered by primary care providers and gastroenterologists. Disorders of chronic constipation, including irritable bowel syndrome with constipation, chronic idiopathic constipation, and opioid-induced chronic constipation, are associated with significant medical costs and a negative impact on quality of life. Although there is evidence supporting the effectiveness of some over-the-counter laxatives in chronic constipation, currently there is no evidence supporting lifestyle modification, dietary change or over-the-counter laxatives as effective long-term therapy for patients with chronic constipation. Lubiprostone is a prostaglandin-derived bicyclic fatty acid available to use for long-term treatment of constipation. Lubiprostone works by increasing intraluminal chloride ion secretion, which results in a passive influx of water and sodium, leading to increased intestinal peristalsis and colonic laxation with decreased intestinal stool transit time. Randomized, double-blind, placebo-controlled trials of lubiprostone in patients with chronic constipation, irritable bowel syndrome and opioid-induced constipation have shown it to be effective and free of serious adverse effects. The most common side effects associated with lubiprostone are mild to moderate nausea and diarrhea. Currently lubiprostone is approved for treatment of chronic constipation and opioid-induced constipation for men and women at 24 µg twice daily and for treatment of irritable bowel syndrome with constipation in women at 8 µg twice daily. Additional research continues to shed light on the molecular mechanisms of lubiprostone and further work may expand its clinical applications.

Lubiprostone increases spontaneous bowel movement frequency and quality of life in patients with chronic idiopathic constipation

BACKGROUND & AIMS

Lubiprostone is an activator of the type 2 chloride channel that facilitates spontaneous bowel movement (SBM). We performed phase 3 studies to determine whether lubiprostone increases the frequency of SBM in patients with chronic idiopathic constipation (CIC) in Japan, and whether long-term administration of lubiprostone increases the quality of life of patients with CIC.

METHODS

We performed a randomized, double-blind, placebo-controlled, phase 3 trial of lubiprostone. Patients with CIC (n = 124) were assigned randomly to groups given placebo (n = 62) or lubiprostone (48 μg/day; n = 62) for 4 weeks. The primary efficacy end point was the change from baseline in the weekly average number of SBMs after 1 week of administration. In a long-term study of efficacy and safety, 209 patients with CIC were given lubiprostone (24 μg twice daily) for 48 weeks.

RESULTS

Daily administration of lubiprostone induced a significantly greater change, from baseline, in the weekly average number of SBMs at week 1 (increase of 3.7 ± 2.8), compared with placebo (increase of 1.3 ± 1.8; P < .001). The frequency of SBMs during each week of the study period was significantly higher after subjects began receiving lubiprostone than at baseline (P < .0001 at all weeks). Long-term administration of lubiprostone significantly increased scores from the Short-Form health survey and irritable bowel syndrome quality-of-life questionnaire, compared with baseline. We did not observe any severe adverse reactions to lubiprostone.

CONCLUSIONS

In phase 3 studies in Japan, lubiprostone increased the weekly average number of SBMs and increased the quality of life of patients with CIC. Clinical Trial Notification of the Japanese Regulatory Authorities: 20-3296 and 20-3300.

Survey of clinical practice for irritable bowel syndrome in East asian countries

AIM

Sociocultural factors are important because their different effects on the features of irritable bowel syndrome (IBS) between countries will provide clues towards solving this problem. The aims of this study were to depict the clinical realities of IBS in East Asian countries and test the hypothesis that the diagnosis and treatment of IBS differ between countries.

SUBJECTS AND METHODS

Study participants were 251 physicians involved in the clinical practice of IBS at major institutions in Japan, South Korea, China, the Philippines, Indonesia and Singapore. The questionnaire contained 45 questions focused on the clinical practice of IBS.

RESULTS

Subjects in Japan, South Korea, China, Indonesia, the Philippines and Singapore accounted for 55.4, 17.9, 8.8, 8.0, 6.4 and 3.6% of the study cohort, respectively. Amongst East Asian physicians, the most important symptom was considered to be abdominal pain by 33.4%, whilst 24.3% regarded alternating diarrhea and constipation to be the most important symptoms. Total colonoscopy and histopathology use showed no difference among countries. Prescriptions given for mild (p < 0.0001), moderate (p < 0.0001), severe (p < 0.0001), intractable (p = 0.002), diarrheal (p < 0.0001) and constipating (p < 0.0001) patients with IBS significantly differed between the countries. Except for several minor points, IBS specialists showed no significant difference in their diagnosis and treatment of IBS when compared to nonspecialists.

CONCLUSION

This survey provided data on the clinical treatment of IBS among East Asian countries. The results supported the hypothesis that the diagnosis and treatment of IBS differs between countries.

Evidence-based clinical practice guidelines for irritable bowel syndrome

New strategies for the care of irritable bowel syndrome (IBS) are developing and several novel treatments have been globally produced. New methods of care should be customized geographically because each country has a specific medical system, life style, eating habit, gut microbiota, genes and so on. Several clinical guidelines for IBS have been proposed and the Japanese Society of Gastroenterology (JSGE) subsequently developed evidence-based clinical practice guidelines for IBS. Sixty-two clinical questions (CQs) comprising 1 definition, 6 epidemiology, 6 pathophysiology, 10 diagnosis, 30 treatment, 4 prognosis, and 5 complications were proposed and statements were made to answer to CQs. A diagnosis algorithm and a three-step treatment was provided for patients with chronic abdominal pain or abdominal discomfort and/or abnormal bowel movement. If more than one alarm symptom/sign, risk factor and/or routine examination is positive, colonoscopy is indicated. If all of them, or the subsequent colonoscopy, are/is negative, Rome III or compatible criteria is applied. After IBS diagnosis, step 1 therapy consisting of diet therapy, behavioral modification and gut-targeted pharmacotherapy is indicated for four weeks. Non-responders to step 1 therapy proceed to the second step that includes psychopharmacological agents and simple psychotherapy for four weeks. In the third step, for patients non-responsive to step 2 therapy, a combination of gut-targeted pharmacotherapy, psychopharmacological treatments and/or specific psychotherapy is/are indicated. Clinical guidelines and consensus for IBS treatment in Japan are well suited for Japanese IBS patients; as such, they may provide useful insight for IBS treatment in other countries around the world.