Recent advances in the pharmacological management of constipation predominant irritable bowel syndrome

Cisapride versus Maren Pill for Functional Constipation: A Meta-Analysis

Background

The efficacy and safety of cisapride in functional constipation (FC) remain unclear. This meta-analysis aimed at investigating the efficacy and safety of cisapride and Maren pill in the treatment of FC. Material and Methods. PubMed, Web of Science, Embase, Cochrane Library, WANFANG DATA, VIP, and CNKI databases were searched from inception to December 2021 for eligible comparative studies investigating the effects and safety of cisapride and Maren pill for FC. The primary outcome was the therapeutic effectiveness rate. The secondary outcomes were recurrence rate and incidence of adverse events.

Results

A total of 526 studies were screened out by searching the electronic databases and by manually searching the relevant reference lists. According to the four-step process (identification, screening, eligibility, and inclusion) to select studies for meta-analysis, 521 articles were excluded. Finally, 5 studies with a total of 414 patients with FC were included in the quantitative analysis after sequential exclusion. The cisapride group had a significantly higher effectiveness rate than the control one (90.78% vs 64.97%, P < 0.05). The incidence of adverse events in the cisapride group was lower than that in the Maren pill group (10.08% vs 13.95%, P < 0.05). Similarly, the recurrence rate of the cisapride group was lower than that of the Maren pill group (32.31% vs 53.16%, P < 0.05).

Conclusion

For FC patients, cisapride is more effective than Maren pill; the recurrence rate and adverse event rate are lower than the latter, which makes it a better choice. The combination of cisapride and Maren pill is a direction of future research studies, which may increase the efficiency and reduce the dosage of cisapride.

Networks Are Associated With Acupuncture Treatment in Patients With Diarrhea-Predominant Irritable Bowel Syndrome: A Resting-State Imaging Study

Background: Irritable Bowel Syndrome (IBS), as a functional gastrointestinal disorder, is characterized by abdominal pain and distension. Recent studies have shown that acupuncture treatment improves symptoms of diarrhea-predominant irritable bowel syndrome (IBS-D) by altering networks in certain brain regions. However, few studies have used resting-state functional magnetic resonance imaging (fMRI) to compare altered resting-state inter-network functional connectivity in IBS-D patients before and after acupuncture treatment. Objective: To analyze altered resting-state inter-network functional connectivity in IBS-D patients before and after acupuncture treatment. Methods: A total of 74 patients with IBS-D and 31 healthy controls (HCs) were recruited for this study. fMRI examination was performed in patients with IBS-D before and after acupuncture treatment, but only at baseline in HCs. Data on the left frontoparietal network (LFPN), default mode network (DMN), salience network (SN), ventral attention network (VAN), auditory network (AN), visual network (VN), sensorimotor network (SMN), dorsal attention network (DAN), and right frontoparietal network (RFPN) were subjected to independent component analysis (ICA). The functional connectivity values of inter-network were explored. Results: Acupuncture decreased irritable bowel syndrome symptom severity score (IBS-SSS) and Hamilton Anxiety Scale (HAMA). It also ameliorated symptoms related to IBS-D. Notably, functional connectivity between AN and VAN, SMN and DMN, RFPN and VAN in IBS-D patients after acupuncture treatment was different from that in HCs. Furthermore, there were differences in functional connectivity between DMN and DAN, DAN and LFPN, DMN and VAN before and after acupuncture treatment. The inter-network changes in DMN-VAN were positively correlated with changes in HAMA, life influence degree, and IBS-SSS in IBS-D. Conclusion: Altered inter-network functional connectivity is involved in several important hubs in large-scale networks. These networks are altered by acupuncture stimulation in patients with IBS-D.

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.

Diagnosing Constipation Spectrum Disorders in a Primary Care Setting

Understanding pathophysiological causes of constipation is worthwhile in directing therapy and improving symptoms. This review aims to identify and fill gaps in the understanding of the pathophysiology of constipation, understand its prevalence, review diagnostic tools available to primary care physicians (PCPs), and highlight patients’ expectations for the management of this common spectrum of disorders. Literature searches conducted via PubMed included terms related to constipation, diagnosis, and patient perceptions. Case studies were developed to highlight the differences between patients who may be appropriately managed in the primary care setting and those requiring specialty consultation. Myriad pathophysiological factors may contribute to constipation, including stool consistency, altered intestinal motility, gut microbiome, anorectal abnormalities, as well as behavioral and psychological factors. Common diagnoses of “primary constipation” include slow-transit constipation, defecation disorders, irritable bowel syndrome with constipation, and chronic idiopathic constipation. A detailed medical history should be conducted to exclude alarm features and PCPs should be familiar with pathophysiological factors that cause constipation, available diagnostic tools, alarm signs, and the various classification criteria for constipation subtypes in order to diagnose and treat patients accordingly. PCPs should understand when a referral to a gastroenterologist, anorectal specialist, pelvic floor physical therapist, and/or mental health specialist is appropriate.

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.