Linaclotide in Chronic Idiopathic Constipation Patients with Moderate to Severe Abdominal Bloating: A Randomized, Controlled Trial

Efficacy and safety of linaclotide in treatment-resistant chronic constipation: A multicenter, open-label study

BACKGROUND

This study aimed to evaluate the efficacy and safety of linaclotide in patients with chronic constipation (CC) or irritable bowel syndrome with constipation (IBS-C) who did not respond to treatment with magnesium oxide (MgO).

METHODS

This study was designed as a multicenter, open-label, single-arm, exploratory study. Patients with CC or IBS-C who took MgO and those meeting the medication initiation criteria were administered linaclotide at a daily dosage of 500 μg for 12 weeks. The primary endpoint was a change in the Japanese version of the Patient Assessment of Constipation Quality of Life (JPAC-QOL) score from baseline, which was evaluated by using a paired t-test.

KEY RESULTS

The patients' mean age (± standard deviation) was 67.6 ± 13.82 years. The full analysis set included 61 patients. The JPAC-QOL total score was 1.60 at baseline and 0.70 at 12 weeks, with a significant mean change of -0.89 ± 0.721 (p < 0.001). Several secondary endpoints also showed improvement. The frequency of spontaneous bowel movement (SBM) and complete SBM increased by 2.70 ± 7.254 (p < 0.01) and 2.81 ± 5.254 times, respectively (p < 0.001). The Bristol Stool Form Scale, abdominal bloating severity, and straining severity scores improved by 1.33 ± 1.274 (p < 0.001), -0.16 ± 0.563 (p < 0.05), and -0.46 ± 0.795 (p < 0.001) points, respectively. The safety analysis set included 65 patients, 7 of whom had diarrhea, which improved with dose reduction and drug withdrawal.

CONCLUSION & INFERENCES

The study was conducted in an older adult population, similar to real clinical practice. Linaclotide may be an option for treating CC that shows an inadequate response to conventional therapy.

A real-world study of persistence and adherence to prescription medications in patients with chronic idiopathic constipation in the United States

BACKGROUND

At present, 4 prescription therapies have been approved by the US Food and Drug Administration for the treatment of chronic idiopathic constipation (CIC) in adults.

OBJECTIVES

To compare persistence with and adherence to prucalopride vs 3 other prescription medications for CIC in a US population.

METHODS

This retrospective, observational cohort study used data from the IBM MarketScan Commercial Claims and Encounters and Medicare Supplemental Databases (January 2015-June 2020). Inclusion criteria were patients (aged ≥18 years) with at least 1 prescription fill for prucalopride, lubiprostone, linaclotide, or plecanatide on or after April 2, 2019 (commercial availability of prucalopride), and at least 1 constipation-related diagnosis code. Persistence was assessed by time to discontinuation, and adherence was assessed by the proportion of days covered (PDC) and the proportion of patients who achieved PDC of at least 80%. Adjusted hazard ratios (HRs) for discontinuation and odds ratios for adherence were calculated.

RESULTS

A total of 14,700 patients (mean age = 48.3 years; female = 81.9%) were included (prucalopride, n = 675; lubiprostone, n = 1,591; linaclotide, n = 11,105; plecanatide, n = 1,329). After adjusting for confounding factors, the HRs for discontinuation were significantly higher for all comparator medications compared with prucalopride after 2 months (HR [95% CI]: lubiprostone, 1.70 [1.48-1.95]; linaclotide, 1.25 [1.10-1.41]; plecanatide, 1.31 [1.13-1.51], all P < 0.001). The unadjusted mean (SD) PDC was 0.53 (0.32) with prucalopride compared with 0.41 (0.31); P less than 0.001 with lubiprostone, 0.48 (0.31), P less than 0.05 with linaclotide, and 0.48 (0.29), P = 0.98 with plecanatide. The comparator medications were all associated with lower odds of achieving PDC of at least 80% relative to prucalopride (odds ratio [95% CI]: lubiprostone, 0.52 [0.40-0.69], P < 0.001; linaclotide, 0.73 [0.58-0.93], P = 0.009; plecanatide, 0.70 [0.53-0.93], P = 0.015).

CONCLUSIONS

The findings of this study indicate that prucalopride has higher treatment persistence and adherence compared with other CIC prescription medications. This research represents the first instance of a real-world claims study showcasing such outcomes.

Treatment and Management of Gastrointestinal Disorders

This article reviews the evaluation and management of several gastrointestinal disorders that are commonly encountered by gastroenterologists and primary care physicians. With a focus on newer therapies, we discuss the management of chronic constipation, irritable bowel syndrome, Clostridioides difficile infection, gastroparesis, steatotic liver disease, and diverticulitis.

Evidence-Based Clinical Guidelines for Chronic Constipation 2023

The Japan Gastroenterological Association published the first version of its clinical guidelines for chronic constipation 2023. Based on the latest evidence, these guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic constipation. They include flowcharts for both diagnosis and treatment of chronic constipation. In the treatment of chronic constipation, the first step involves differentiating between secondary forms, such as organic disease-associated constipation, systemic disease-associated constipation, and drug-induced constipation. The next step is to determine whether the chronic constipation stems from a motility disorder, a form of primary chronic constipation. For functional constipation and constipation-predominant irritable bowel syndrome, treatment should be initiated after evaluating symptoms like reduced bowel movement frequency type or defecation difficulty type. The first line of treatment includes the improvement of lifestyle habits and diet therapy. The first drugs to consider for oral treatment are osmotic laxatives. If these are ineffective, secretagogues and ileal bile acid transporter inhibitors are candidates. However, stimulant laxatives are exclusively designated for as-needed use. Probiotics, bulk-forming laxatives, prokinetics, and Kampo medicines, for which there is insufficient evidence, are considered alternative or complementary therapy. Providing the best clinical strategies for chronic constipation therapy in Japan, these clinical guidelines for chronic constipation 2023 should prove useful for its treatment worldwide. The Japan Gastroenterological Association published the first version of its clinical guidelines for chronic constipation 2023. Based on the latest evidence, these guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic constipation. They include flowcharts for both diagnosis and treatment of chronic constipation. In the treatment of chronic constipation, the first step involves differentiating between secondary forms, such as organic disease-associated constipation, systemic disease-associated constipation, and drug-induced constipation. The next step is to determine whether the chronic constipation stems from a motility disorder, a form of primary chronic constipation. For functional constipation and constipation-predominant irritable bowel syndrome, treatment should be initiated after evaluating symptoms like reduced bowel movement frequency type or defecation difficulty type. The first line of treatment includes the improvement of lifestyle habits and diet therapy. The first drugs to consider for oral treatment are osmotic laxatives. If these are ineffective, secretagogues and ileal bile acid transporter inhibitors are candidates. However, stimulant laxatives are exclusively designated for as-needed use. Probiotics, bulk-forming laxatives, prokinetics, and Kampo medicines, for which there is insufficient evidence, are considered alternative or complementary therapy. Providing the best clinical strategies for chronic constipation therapy in Japan, these clinical guidelines for chronic constipation 2023 should prove useful for its treatment worldwide.

Clinical effects of chemical drugs, fecal microbiota transplantation, probiotics, dietary fiber, and acupuncture in the treatment of chronic functional constipation: a systematic review and network meta-analysis

Currently, there are increasingly diverse treatment modalities for chronic functional constipation (CFC). This study aims to compare the relative efficacy and safety of chemical drugs, fecal microbiota transplantation (FMT), probiotics, dietary fiber, and acupuncture in the treatment of patients with CFC. We searched relevant randomized controlled trials (RCTs) published in five databases up to November 2023. Network meta-analysis (NMA) was carried out using R Studio 4.2.1. Cumulative ranking probability plots, assessed through the surface under the cumulative ranking (SUCRA), were employed to rank the included drugs for various outcome measures. We included a total of 45 RCT studies with 17 118 patients with CFC. From the SUCRA values and NMA results FMT showed the best utility in terms of clinical efficacy, Bristol stool form scale scores, patient assessment of constipation quality of life scores, and the treatment modality with the lowest ranked incidence of adverse effects was electroacupuncture. Subgroup analysis of the chemotherapy group showed that sodium A subgroup analysis of the chemical group showed that sodium picosulfate 10 mg had the highest clinical efficacy. FMT is more promising in the treatment of CFC and may be more effective in combination with the relatively safe treatment of acupuncture.

Pharmacologic Treatment of Chronic Constipation

Chronic constipation is a common disease that can impair the quality of life, with a prevalence of 14% globally and 16.5% in South Korea. Straining, hard stools, the sensation of incomplete evacuation, the sensation of anorectal blockage, and manual maneuvers to facilitate defecation are the related symptoms of chronic constipation. On the other hand, medications commonly referred to as laxatives are the essentials of treatment for constipation compared to non-pharmacological treatment, such as lifestyle modifications, biofeedback, or surgery. Unfortunately, there is still an unmet need to determine if pharmacological treatment for constipation is being administered appropriately. Therefore, there are many disadvantages as to whether the indications and side effects of laxatives are adequately considered and prescribed as the primary treatment modality for constipation in a real clinical situation in Korea. Laxatives are generally recommended as the next step for patients in whom organic causes have been excluded and have not responded to initial non-pharmacologic therapies such as dietary fiber intake and exercise. Laxatives can be classified as bulk-forming laxatives, osmotic laxatives, stimulant laxatives, and other novel laxatives. On the other hand, there are distinct mechanisms underlying constipation, and appropriate administration is the most decisive. Therefore, the present investigators prepared this review to discuss appropriate pharmacological strategies for chronic constipation in Korea. Moreover, this paper also includes suggestions for appropriate pharmacological treatment options for special patient populations.

Randomized controlled trial of linaclotide in children aged 6-17 years with functional constipation

OBJECTIVES

Linaclotide, a guanylate cyclase-C agonist, was recently approved in the United States for treatment of children 6-17 years old with functional constipation (FC). This study evaluated the safety and efficacy of several linaclotide doses in children 6-17 years old with FC.

METHODS

In this multicenter, randomized, double-blind, placebo-controlled phase 2 study, 173 children with FC (based on Rome III criteria) were randomized to once-daily linaclotide (A: 9 or 18 μg, B: 18 or 36 μg, or C: 36 or 72 μg) or placebo in a 1:1:1:1 ratio for 6- to 11-year-olds (dosage determined by weight: 18 to <35 or ≥35 kg) and linaclotide (18, 36, 72, or 145 μg) or placebo in a 1:1:1:1:1 ratio for 12- to 17-year-olds. The primary efficacy endpoint was change from baseline in weekly spontaneous bowel movement (SBM) frequency throughout the 4-week treatment period. Adverse events (AE), clinical laboratory values, and electrocardiograms were monitored.

RESULTS

Efficacy and safety were assessed in 173 patients (52.0% aged 6-11 years; 48.0% aged 12-17 years); 162 (93.6%) completed the treatment period. A numerical improvement in mean SBM frequency was observed with increasing linaclotide doses (1.90 in 6- to 11-year-olds [36 or 72 μg] and 2.86 in 12- to 17-year-olds [72 μg]). The most reported treatment-emergent AE was diarrhea, with most cases being mild; none were severe.

CONCLUSIONS

Linaclotide was well tolerated in this pediatric population, with a trend toward efficacy in the higher doses, warranting further evaluation.

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.

Relationship Between Colonic Transit Response to Eating With Self-reported Constipation Severity in Constipated Patients According to the Phenotype

Background/Aims

Eating is the major synchronizer of gastrointestinal motility and secretions. The present study aims to evaluate the interplay between self-perceived constipation severity (CS) and colonic response to eating in constipated patients according to the phenotype.

Methods

We included 387 consecutive outpatients complaining of Rome IV chronic idiopathic constipation. Likert scales for CS, abdominal pain severity, bloating severity, depression and anxiety assessment, total and segmental colonic transit time (CTT), and colonic transit response to eating (CTRE) were performed in all patients.

Results

Of the 387 patients included (49.7 ± 16.4 years), 320 (83%) were female, 203 had irritable bowel syndrome with constipation (IBS-C), 184 as functional constipation (FC), and 283 had defecation disorders (DD). The female gender was characterized by increased bloating severity (P = 0.011) and decreased Bristol stool form (P = 0.002). In IBS-C and FC patients, CS was related with bloating severity (P < 0.001 in both groups) and total CTT (P = 0.007 in IBS-constipation, P = 0.040 in FC). In IBS-C patients, CS was also associated with abdominal pain severity (P = 0.003) and Bristol stool form (P = 0.004). In contrast, in FC, CS was only related to left CTRE (P = 0.006), and in patients with DD, CS was associated with total CTT (P < 0.001) and left CTRE (P = 0.002).

Conclusion

Colonic transit response to eating was not associated to CS in IBS-C patients, but left CTRE was associated with constipation severity in FC and DD patients.

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.

Nutritional Management of Oncological Symptoms: A Comprehensive Review

Throughout their experience of illness and during the course of treatment, a substantial proportion of cancer patients are prone to develop nutritional and/or metabolic disturbances. Additionally, cancer patients often encounter long-term side effects from therapies, which may lead to impaired digestion, nutrient absorption or bowel motility. Therefore, the preservation and maintenance of an optimal and balanced nutritional status are pivotal to achieving a better prognosis, increasing the tolerance and adherence to cancer therapies and improving the overall quality of life. In this context, personalized nutritional programs are essential for addressing conditions predisposing to weight loss, feeding difficulties, digestion problems and intestinal irregularity, with the goal of promoting adequate nutrient absorption and minimizing the detrimental effects of treatment regimens. The focus of this research is to examine the most common clinical conditions and metabolic changes that cancer patients may experience, including stomatitis, xerostomia, diarrhea, nausea, vomiting, dysphagia, sub-occlusion, dysgeusia, dysosmia, anorexia, and cachexia. Furthermore, we present a pragmatic example of a multidisciplinary workflow that incorporates customized recipes tailored to individual clinical scenarios, all while maintaining the hedonic value of the meals.

Clinical Characteristics of Patients Presenting With Bloating as a Predominant Symptom

BACKGROUND

The estimated prevalence of bloating is 15 to 30% in the adult US population and is even higher in patients with disorders of gut-brain interaction (DGBIs). Despite this frequency, there is little research into patients who endorse bloating as a predominant symptom. The aim of this study was to better characterize these patients.

MATERIALS AND METHODS

New patients with DGBIs were asked to identify their 3 most predominant symptoms over the preceding 3 months; those who reported bloating were classified as "bloating predominant." Rome IV and symptom-specific questionnaires were administered to assess for the frequency of DGBIs and other predominant symptoms in this patient population. Using univariable and multivariable modeling, we analyzed the associations between bloating predominance, DGBI subtype, and clinical characteristics.

RESULTS

Of the 586 patients surveyed, 242 (41%) reported predominant bloating. Bloating-predominant patients were more likely to be female, younger, and meet the criteria for IBS-mixed (IBS-M), functional constipation, and functional dyspepsia compared with nonbloating-predominant patients. Bloating-predominant patients were also more likely to endorse concurrently predominant constipation, incomplete evacuation, abdominal pain, belching, and/or nausea. On multivariable logistic regression, constipation and abdominal pain severity were positively associated, although depression was negatively associated with predominant bloating.

CONCLUSIONS

Patients with predominant bloating are more likely to have constipation-related symptoms than diarrhea-related symptoms. They are also more likely to have more severe abdominal pain than patients without predominant bloating. These findings help characterize patients with bloating as a predominant symptom and suggest that diagnosing and treating constipation should be considered as first-line treatment.

The Intestinal Tract Brush Border in Young Children Uniformly Expresses Guanylate Cyclase C

The present study examined staining of guanylate cyclase C (GCC/GUCY2C) in the small and large intestines of children younger than age 7 years. Normal intestinal tissue from children aged 0 to 7 years was stained using GCC, uroguanylin, and villin antibodies and scored for staining intensity. A subset underwent quantitative real-time polymerase chain reaction. Data were analyzed using t test of independent means, descriptive statistics, and logistic regression. Four hundred sixty-four specimens underwent immunohistochemistry; 291 specimens underwent real-time polymerase chain reaction. GCC, villin, and uroguanylin were detected across age groups and anatomic sites. No significant differences were identifiable across age groups. GUCY2C and uroguanylin mRNA was detected in all samples, with no variability of statistical significance of either target-to-villin normalization between any age cohorts. A gradient of expression of GCC across age groups does not seem to exist.

Intestinal neuropod cell GUCY2C regulates visceral pain

Visceral pain (VP) is a global problem with complex etiologies and limited therapeutic options. Guanylyl cyclase C (GUCY2C), an intestinal receptor producing cyclic GMP(cGMP), which regulates luminal fluid secretion, has emerged as a therapeutic target for VP. Indeed, FDA-approved GUCY2C agonists ameliorate VP in patients with chronic constipation syndromes, although analgesic mechanisms remain obscure. Here, we revealed that intestinal GUCY2C was selectively enriched in neuropod cells, a type of enteroendocrine cell that synapses with submucosal neurons in mice and humans. GUCY2Chi neuropod cells associated with cocultured dorsal root ganglia neurons and induced hyperexcitability, reducing the rheobase and increasing the resulting number of evoked action potentials. Conversely, the GUCY2C agonist linaclotide eliminated neuronal hyperexcitability produced by GUCY2C-sufficient - but not GUCY2C-deficient - neuropod cells, an effect independent of bulk epithelial cells or extracellular cGMP. Genetic elimination of intestinal GUCY2C amplified nociceptive signaling in VP that was comparable with chemically induced VP but refractory to linaclotide. Importantly, eliminating GUCY2C selectively in neuropod cells also increased nociceptive signaling and VP that was refractory to linaclotide. In the context of loss of GUCY2C hormones in patients with VP, these observations suggest a specific role for neuropod GUCY2C signaling in the pathophysiology and treatment of these pain syndromes.

Polyethylene Glycol 3350 in the Treatment of Chronic Idiopathic Constipation: Post hoc Analysis Using FDA Endpoints

METHODS

This multicenter, double-blind, placebo-controlled, parallel-group trial included adults with chronic idiopathic constipation randomized to polyethylene glycol 3350 17 g (n = 204) or placebo (n = 100) once daily for 24 weeks. Post hoc analyses were performed using the US Food and Drug Administration endpoint (≥3 complete spontaneous bowel movements/week and an increase of ≥1 complete spontaneous bowel movement/week from baseline for ≥9/12 weeks, including 3 of the last 4 weeks) along with additional efficacy and safety outcomes.

RESULTS

The proportion of patients meeting the new endpoint was significantly higher with polyethylene glycol 3350 vs placebo (42% vs 13%; P < 0.0001). Reductions in the mean number of hard/lumpy stools/week (-2.1 vs -0.9; P = 0.0014) and the weekly mean five-point cramping rating (-0.3 vs -0.1; P = 0.0272) also significantly favored polyethylene glycol 3350. The proportion of subjects with gastrointestinal adverse events decreased markedly after the first week of treatment in the polyethylene glycol 3350 group.

CONCLUSION

Using the current US Food and Drug Administration-recommended responder definition and other secondary outcomes, once-daily polyethylene glycol 3350 demonstrated substantial and sustained efficacy and safety over 24 weeks in patients with chronic idiopathic constipation. Trial Registration. The original trial was registered with https://clinicaltrials.gov Trial: NCT00153153.

Effects of linaclotide in the treatment of chronic constipation and irritable bowel syndrome with constipation: a meta-analysis

OBJECTIVE

Linaclotide is a guanylate cyclase-C (GCC) agonist that is found in intestinal epithelial cells and is used when treating chronic constipation (CC) and irritable bowel syndrome with constipation (IBS-C). Several randomized controlled trials (RCTs) were conducted for evaluating its efficacy and safety.

METHODS

The PubMed, EMBASE, and Cochrane databases and the Web of Science were searched to find multiple RCTs of patients with CC or IBS-C. The Jadad scoring system was used for evaluating each study's methodological quality, and RevMan5.3 was used for meta-analysis. The composite endpoint reaction approved by the FDA, abdominal pain and discomfort relief, symptom improvement, and diarrhea-related adverse reactions were chosen as observation indicators, and relative risk (RR) and 95% confidence interval (CI) were obtained for quantitative and comprehensive evaluation.

RESULTS

Eleven randomized controlled studies were included, consisting of 5 cases of CC and 6 cases of IBS-C. Linaclotide reached the composite endpoint response approved by FDA in the treatment of CC (RR = 3.26, 95% CI: 2.45-4.33), and the composite endpoint response approved by FDA for the treatment of IBS-C (RR = 2.26, 95% CI: 1.86-2.74) was greater than the placebo (both p < 0.00001). The main adverse reactions of linaclotide were gastrointestinal, mostly diarrhea, which was higher than that of the placebo when treating CC (RR = 3.56, 95% CI: 2.76-4.60) and IBS-C (RR = 8.23, 95% CI: 5.69-11.90) (both p < 0.00001).

CONCLUSION

Linaclotide proved to be effective and safe for the treatment of CC and IBS-C compared to the placebo. However, diarrhea is the primary adverse reaction.

Symptom severity and clinical characteristics of patients with bloating

BACKGROUND

Abdominal bloating is common in functional gastrointestinal disorders (FGID). To better characterize this patient population, we evaluated clinical and psychological characteristics of bloating and analyzed their differences by bloating severity.

METHODS

Patients with FGIDs evaluated at a single academic outpatient referral gastroenterology clinic were surveyed. Bloating severity was classified as minimal, moderate or severe. Symptom-specific questionnaires were used to evaluate bowel habits, abdominal bloating, depression, anxiety, somatization and sleep disturbance. Associations between bloating severity, clinical characteristics and FGID subtypes were analyzed in univariate and multivariate modeling.

KEY RESULTS

Of 612 FGID patients included (78% female, mean age of 44 ± 16.5 years), bloating was reported as minimal in 231(37.8%), moderate in 217(35.4%), or severe in 164(26.8%). Patients with severe bloating were more likely to be female, younger, and have co-existing functional dyspepsia than those with minimal bloating (p < 0.05). Bloating severity and severity of abdominal distension were significantly correlated (p < 0.05). On multivariable regression, patients who met criteria for functional constipation and functional dyspepsia had 80% and 125% higher odds, respectively, of severe bloating compared to minimal to moderate bloating. Younger age, abdominal pain and constipation severity, and somatization scores were also independently associated with severity of bloating.

CONCLUSIONS & INFERENCES

Severe bloating is associated with younger age, and with more severe abdominal pain, constipation, and somatization. Patients who met criteria for functional constipation and functional dyspepsia are more likely to experience severe bloating.

A Practical Approach to the Diagnosis and Treatment of Abdominal Bloating and Distension

Abdominal bloating and distension are highly prevalent symptoms that can negatively impact quality of life and lead to medical consultation. Despite their prevalence, symptoms of bloating and distension pose a unique diagnostic and therapeutic challenge, as they are inherently nonspecific symptoms with a complex etiology, and no uniform diagnostic or treatment algorithm currently exists. Additionally, bloating is common among disorders of gut-brain interaction, which can be difficult to treat. This article offers a practical approach for evaluating and treating symptoms of bloating and distension through discussion of 5 common etiologies: diet, small intestinal bacterial over-growth, constipation, visceral hypersensitivity, and abdomino-phrenic dyssynergia. An effective personalized evaluation and treatment plan can be established to address symptoms of bloating and distension through consideration of these etiologies in the context of the patient's individual characteristics and presentation.

Guanylate cyclase-C agonists as peripherally acting treatments of chronic visceral pain

Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain and altered bowel habit that affects ~11% of the global population. Over the past decade, preclinical and clinical studies have revealed a variety of novel mechanisms relating to the visceral analgesic effects of guanylate cyclase-C (GC-C) agonists. Here we discuss the mechanisms by which GC-C agonists target the GC-C/cyclic guanosine-3',5'-monophosphate (cGMP) pathway, resulting in visceral analgesia as well as clinically relevant relief of abdominal pain and other sensations in IBS patients. Due to the preponderance of evidence we focus on linaclotide, a 14-amino acid GC-C agonist with very low oral bioavailability that acts within the gut. Collectively, the weight of experimental and clinical evidence supports the concept that GC-C agonists act as peripherally acting visceral analgesics.

Comparison of the Efficacy and Safety of Different Doses of Linaclotide for Patients with Chronic Constipation: A Meta-Analysis and Bayesian Analysis

BACKGROUND

It is ambiguous whether a higher dose of linaclotide provides higher efficacy for chronic constipation (CC) patients. The meta-analysis aimed to assess the efficacy and safety of linaclotide doses ranging from 62.5 μg to 600 μg for CC patients.

METHODS

A comprehensive search was conducted, and STATA16 software was used for data analysis.

RESULTS

Seven studies with 4,107 patients were eligible. A significantly enhanced number of completely spontaneous bowel movement (CSBM) responders were found in the extremely low-dose group (OR: 2.94; 95% CI: 1.98-4.34; p < 0.001), the low-dose group (OR: 3.24; 95% CI: 2.44-4.31; p < 0.001), the medium-dose group (OR: 3.08; 95% CI: 1.46-6.50; p=0.003), and high-dose group (OR: 4.79; 95% CI: 3.04-7.54; p < 0.001). Bayesian analysis showed the high-dose group obtained the maximum CSBM responder rate (OR: 4.94; 95% credible interval (CrI): 3.22-7.79; probability rank = 0.87) indirectly compared with extremely low-dose, low-dose, and medium-dose groups. However, no significant difference presented in the CSBM responder rate by pairwise comparisons of the different dose groups. Additionally, no more any adverse events occurred in the higher linaclotide dose group (RR: 0.91; 95% CrI: 0.60-1.38) indirectly compared with other dose groups.

CONCLUSIONS

High dose of linaclotide could be more effective and safer for CC patients, which need more trials to confirm in the future.

Bisacodyl: A review of pharmacology and clinical evidence to guide use in clinical practice in patients with constipation

BACKGROUND

Bisacodyl is a member of the diphenylmethane family and is considered to be a stimulant laxative. It has a dual prokinetic and secretory action and needs to be converted into the active metabolite bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM) in the gut to achieve the desired laxative effect. Bisacodyl acts locally in the large bowel by directly enhancing the motility, reducing transit time, and increasing the water content of the stool. A recent network meta-analysis concluded that bisacodyl showed similar efficacy to prucalopride, lubiprostone, linaclotide, tegaserod, velusetrag, elobixibat, and sodium picosulfate for the primary endpoint of ≥3 complete spontaneous bowel movements (CSBM)/week and an increase of ≥1 CSBM/week over baseline. The meta-analysis also found that bisacodyl may be superior to the other laxatives for the secondary endpoint of change from baseline in the number of spontaneous bowel movements per week in patients with chronic constipation. This observation stimulated the authors to review the available literature on bisacodyl, which has been available on the market since the 1950 s.

PURPOSE

The aim of the current review was to provide an overview of the historic background, structure, function, and mechanism of action of bisacodyl. Additionally, we discuss the important features and studies for bisacodyl to understand its peculiar characteristics and guide its use in clinical practice, but also stimulate research on open questions.

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.

Management of functional gastrointestinal disorders

Functional gastrointestinal (GI) disorders (eg irritable bowel syndrome and functional dyspepsia) are very common conditions which are associated with very poor quality of life and high healthcare utilisation. They are caused by disorders of GI functioning, namely altered gut sensitivity, motility, microbiota, immune functioning and central nervous system processing. They cause chronic symptoms throughout the gut (eg pain, dyspepsia and altered bowel habit), all of which are made worse by maladaptive patient behaviours, stress and psychological comorbidity. Management involves a biopsychosocial approach involving changes in lifestyle and diet, addressing coexisting psychological comorbidity and using medication to treat underlying pathophysiology. Pharmacological treatment with antispasmodics, neuromodulators, motility agents and antidepressants is effective. Psychotherapy in motivated individuals is equally effective. Success of treatment is increased by a good doctor-patient relationship and so this needs to be taken into account during the consultation.

Functional Constipation: Individualising Assessment and Treatment

Chronic constipation is one of the five most common symptoms seen by gastroenterologist. In the absence of alarm symptoms, a confident symptom-based diagnosis can often be made using the Rome criteria. Three different subtypes have been identified to date: normal transit constipation, defaecatory disorders and slow transit constipation. Differentiation between these subtypes can be made through functional testing using tests such as anorectal manometry with balloon expulsion and a radio-opaque marker test. In general, patients are initially advised to increase their fluid and fibre intake. When these general lifestyle recommendations do not improve patients' symptoms, a step-wise and add-on treatment approach should be applied. This review summarises the diagnostic criteria to differentiate functional constipation from other causes of chronic constipation. In addition, current drug treatment options, including discussion of new therapeutic targets are discussed. Further, practical treatment approaches (choice and dosing), include discussion of combination/augmentation, treatment failure (adherence/expectations), and relapse prevention are mentioned. Finally, treatment and management of pain and bloating aspects are included.

Management of Chronic Abdominal Distension and Bloating

Abdominal bloating and distension are 2 of the most commonly reported gastrointestinal symptoms. Abdominal bloating is characterized by symptoms of trapped gas, abdominal pressure, and fullness. Abdominal distension is defined as a measurable increase in abdominal girth. These symptoms frequently co-exist, although they can occur separately. Defined by Rome IV criteria, functional abdominal bloating and distension commonly coincide with other functional gastrointestinal disorders, such as functional dyspepsia, irritable bowel syndrome, and functional constipation. Abdominal bloating and distension can develop for multiple reasons, including food intolerances, a previous infection that perturbed the intestinal microbiota, disordered visceral sensation, delayed intestinal transit, or an abnormal viscero-somatic reflux. Treatment can be challenging to patients and providers-no regimen has been consistently successful. Successful treatment involves identifying the etiology, assessing severity, educating and reassuring patients, and setting expectations. Therapeutic options include dietary changes, probiotics, antibiotics, prokinetic agents, antispasmodics, neuromodulators, and biofeedback. We review the epidemiology and effects of chronic bloating and distension and pathophysiology, discuss appropriate diagnostic strategies, and assess available treatment options.

Lessons learned: Chronic idiopathic constipation patient experiences with over-the-counter medications

INTRODUCTION

Chronic idiopathic constipation (CIC) is a prevalent functional gastrointestinal disorder diagnosed based on patient-reported symptoms and the absence of structural gastrointestinal abnormalities. Individuals with CIC typically institute dietary changes and use stool softeners or over-the-counter (OTC) laxatives, possibly at the direction of a healthcare provider, before prescription medications for CIC are initiated. Although highly prevalent, there is limited information regarding CIC patient experiences with OTC medications.

METHODS

This post-hoc analysis used patient-reported data from a questionnaire administered during patient screening for a prospective linaclotide Phase 3b clinical trial in patients with CIC (N = 1482 screened). The questionnaire asked patients to report their experiences with OTC CIC medications over the preceding 6 months.

RESULTS

Among patients with screening responses (N = 1423), most were female (85%) and white (66%), with a mean age of 48.9 years. A high proportion of patients had used one or more OTC medications (70% had ≥1 OTC; 19% had ≥3 OTCs), with the majority being bisacodyl (33%) and polyethylene glycol (30%). The most commonly cited reason for stopping an OTC medication was insufficient symptom relief (17-40%). The majority of patients taking OTC medications reported no or little satisfaction with the medication's effect on their constipation (62%) and CIC-specific abdominal symptoms (78%). Many patients had little to no confidence in bowel movement (BM) frequency after taking OTC medications and their confidence in their ability to predict BM timing was also low (49-81% not at all confident).

CONCLUSIONS

Treatment effects on individual CIC symptoms, predictability of bowel habits, and satisfaction with treatment are all important factors for healthcare providers and patients to consider when establishing an effective treatment regimen for CIC.

TRIAL REGISTRATION NUMBER

NCT01642914.

Impact of Clinical Outcome Measures on Placebo Response Rates in Clinical Trials for Chronic Constipation: A Systematic Review and Meta-analysis

OBJECTIVES

Chronic constipation (CC) is a recurrent functional bowel disorder worldwide. The purpose of this study is to examine its pooled placebo response rate and compare placebo response level in randomized controlled trials (RCTs) with different endpoint assessments.

METHODS

PubMed, Cochrane Library, and Embase were electronically searched for therapeutic RCTs of CC with placebo control. Data extraction and assessment of risk of bias were performed independently by 2 reviewers. All the statistical calculation and analysis were performed using R 3.6.0. Our protocol has registered in PROSPERO with registration number: CRD42019121287.

RESULTS

There were 46 studies included with 5,992 constipated patients allocated to the placebo arm in total. The pooled placebo response rate was 28.75% (95% confidence interval: 23.83%-33.67%) with significant heterogeneity among trials ((Equation is included in full-text article.)= 93.6%). Treatment efficacy assessed using subjective improvement had a significantly higher placebo response rate than that assessed with improvement in complete (spontaneous) bowel movements or composite improvement (41.40% vs 18.31% or 20.35%, P < 0.001). According to the results of meta-regression, active treatment and endpoint assessment were most likely to lead to the huge heterogeneity among studies.

DISCUSSION

Patients with CC have significant response level to placebo. Based on findings in this study, we do not recommend subjective improvement as endpoint while designing therapeutic RCTs for chronic constipated patients.

Management of Opioid-Induced and Non-Opioid-Related Constipation in Patients With Cancer: Systematic Review and Meta-Analysis

PROBLEM IDENTIFICATION

A systematic review and meta-analysis was conducted to inform the development of national clinical practice guidelines on the management of cancer constipation.

LITERATURE SEARCH

PubMed®, Wiley Cochrane Library, and CINAHL® were searched for studies published from May 2009 to May 2019.

DATA EVALUATION

Two investigators independently reviewed and extracted data from eligible studies. The Cochrane Collaboration risk-of-bias tool was used, and the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach was used to assess the certainty of the evidence.

SYNTHESIS

For patients with cancer and opioid-induced constipation, moderate benefit was found for osmotic or stimulant laxatives; small benefit was found for methylnaltrexone, naldemedine, and electroacupuncture. For patients with cancer and non-opioid-related constipation, moderate benefit was found for naloxegol, prucalopride, lubiprostone, and linaclotide; trivial benefit was found for acupuncture.

IMPLICATIONS FOR PRACTICE

Effective strategies for managing opioid-induced and non-opioid-related constipation in patients with cancer include lifestyle, pharmacologic, and complementary approaches.

SUPPLEMENTAL MATERIAL CAN BE FOUND AT&NBSP;HTTPS

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Comparative Efficacy of Drugs for the Treatment of Chronic Constipation: Quantitative Information for Medication Guidelines

BACKGROUND

Quantitative information is scarce with regard to guidelines for currently prescribed medications for constipation. Furthermore, these guidelines do not reflect the differences in the number of bowel movements caused by each drug.

GOALS

In this study, we used a model-based meta-analysis to quantitatively estimate the deviations from the baseline number of spontaneous bowel movements (SBMs) and complete spontaneous bowel movements (CSBMs) associated with pharmacotherapy for chronic constipation to bridge the knowledge gap in the guidelines for current medications.

STUDY

A comprehensive survey was conducted using literature databases. In this study, we also included randomized placebo-controlled trials on chronic constipation. Pharmacodynamic models were established to describe the time course of the numbers of SBMs and CSBMs produced by each drug.

RESULTS

Data from 20 studies (comprising 9998 participants and 8 drugs) were used to build this model. The results showed that bisacodyl had the greatest effect on increasing the frequency of bowel movements, whereas plecanatide yielded the lowest increase in the number of SBMs and CSBMs. After eliminating the placebo effect, the maximal increase in bowel movement frequency associated with bisacodyl was 6.8 for SBMs (95% confidence interval: 6.1-7.6) and 4.7 for CSBMs (95% confidence interval: 4.3-5.1) per week. These numbers are ∼4 times higher than the number of bowel movements produced by plecanatide. The change in the frequency of SBMs and CSBMs for other drugs, such as sodium picosulfate, velusetrag, linaclotide, elobixibat, lubiprostone, and prucalopride, was similar. The highest increases in the frequency of SBM and CSBM were 2.5 to 4 and 1 to 2.1 per week, respectively. Bisacodyl had the most noticeable loss of efficacy between week 1 and week 4; it reduced the frequencies of SBMs and CSBMs by 2.3 and 2.2, respectively. By contrast, the changes in the frequencies of SBMs and CSBMs were not as great with other drugs.

CONCLUSIONS

The data provided in this study may be a valuable supplement to the medication guidelines for the treatment of chronic constipation.

ONS Guidelines™ for Opioid-Induced and Non-Opioid-Related Cancer Constipation

PURPOSE

This evidence-based guideline intends to support clinicians, patients, and others in decisions regarding the treatment of constipation in patients with cancer.

METHODOLOGIC APPROACH

An interprofessional panel of healthcare professionals with patient representation prioritized clinical questions and patient outcomes for the management of cancer-related constipation. Systematic reviews of the literature were conducted. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach was used to assess the evidence and make recommendations.

FINDINGS

The panel agreed on 13 recommendations for the management of opioid-induced and non-opioid-related constipation in patients with cancer.

IMPLICATIONS FOR NURSING

The panel conditionally recommended a bowel regimen in addition to lifestyle education as first-line treatment for constipation. For patients starting opioids, the panel suggests a bowel regimen as prophylaxis. Pharmaceutical interventions are available and recommended if a bowel regimen has failed. Acupuncture and electroacupuncture for non-opioid-related constipation are recommended in the context of a clinical trial.

SUPPLEMENTARY MATERIAL CAN BE FOUND AT&NBSP;HTTPS

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Constipation and the Quality of Life in Conservatively Treated Chronic Kidney Disease Patients: A Cross-sectional Study

Background: Constipation is a common gastrointestinal disorder that in general population is associated with worse health-related quality of life (HRQoL). The epidemiology of constipation has not been reliably determined in conservatively-treated CKD patients. We aimed to determine the prevalence of constipation and constipation-related symptoms in conservatively-treated CKD patients, to find factors associated with their altered prevalence ratio (PR), and to verify the associations between constipation and HRQoL. Methods: In this cross-sectional study, 111 conservatively-treated CKD outpatients fulfilled questionnaires that included questions addressing HRQoL (SF-36v2®), constipation-related symptoms (The Patient Assessment of Constipation-Symptoms questionnaire), the Bristol stool form scale (BSFS), Rome III criteria of functional constipation (FC), and frequency of bowel movement (BM). Results: Depending on the used definition, the prevalence of constipation was 6.6-28.9%. Diuretics and paracetamol were independently associated with increased PR of BSFS-diagnosed constipation (PR 2.86, 95% CI 1.28-6.37, P = 0.01) and FC (PR 2.67, 95% CI 1.07-6.64, P = 0.035), respectively. The most commonly reported symptoms were bloating (50.9%) and straining to pass a BM (42.7%). Abdominal discomfort (37.3%) was independently associated with worse scores in all analyzed HRQoL domains. In multiple regressions, FC and having <7 BM/week, but not BSFS-diagnosed constipation, were associated with lower scores in several HRQoL domains. Conclusions: Constipation and related symptoms are prevalent in CKD patients. FC and decreased frequency of defecation, but not BSFS-diagnosed constipation, are associated with worse assessment of HRQoL in conservatively-treated CKD patients.

Efficacy and safety of linaclotide for opioid-induced constipation in patients with chronic noncancer pain syndromes from a phase 2 randomized study

Constipation is the most common adverse event (AE) of opioid therapy. This multicenter, phase 2 study evaluated the efficacy and safety of linaclotide in treating opioid-induced constipation (OIC) in patients with chronic noncancer pain syndromes (NCT02270983). Adults with OIC (<3 spontaneous bowel movements [SBMs]/week) related to chronic noncancer pain were randomized 1:1:1 to receive linaclotide 145 µg, linaclotide 290 µg, or placebo once daily for 8 weeks. The primary endpoint was change from baseline in 8-week SBM frequency rate (SBMs/week). Secondary efficacy endpoints included 6/8-week SBM 3 + 1 responders, time to first SBM, and changes from baseline in 8-week stool consistency, abdominal bloating, and straining. Additional endpoints included treatment satisfaction and adequate relief responders. In total, 254 patients were randomized: 87, 88, and 79 received linaclotide 145 µg, linaclotide 290 µg, and placebo, respectively. The mean changes from baseline in SBMs/week during the treatment period were 2.9 and 3.5 in the linaclotide 145 and 290 µg groups (P < 0.01 for both doses), respectively, vs 1.6 in the placebo group. Diarrhea, the most common AE, was generally mild, resulting in 1.1%, 5.7%, and 1.3% of patients discontinuing in the linaclotide 145 μg, linaclotide 290 μg, and placebo groups, respectively. No serious AEs related to diarrhea were reported in any treatment group. Compared with placebo, linaclotide-treated patients had significant improvements in stool consistency, straining, abdominal bloating, and treatment satisfaction scores (P < 0.05). Linaclotide significantly improved OIC symptoms and was well tolerated in patients with chronic noncancer pain.

Placebo response rate in patients with chronic constipation: A protocol for systematic review

OBJECTIVE

The aim of this systematic review and meta-analysis is to calculate the pooled placebo response rate in patients with chronic constipation (CC) in randomized controlled trial (RCT) and its related factors.

METHOD

This systematic review and meta-analysis will be conducted under the guidance of Cochrane Handbook. The inclusive and exclusive criteria and search strategies for PubMed, Cochrane Library, and Embase will be introduced in this protocol. Data collection, extraction, and assessment of risk of bias will be conducted independently by 2 reviewers. The pooled placebo response rate and its 95% confidence interval (95%CI) will be calculated and the heterogeneity assessment, publication bias assessment, and subgroup analysis will be performed using R 3.6.0. This study has been registered on the PROSPERO platform (CRD42019121287).

RESULT

The results of this systematic review and meta-analysis will be published in a peer-reviewed journal.

Placebo Response in Chronic Idiopathic Constipation: A Systematic Review and Meta-Analysis

OBJECTIVES

Chronic idiopathic constipation (CIC), like other functional gastrointestinal disorders, has been associated with a high placebo response rate. However, the placebo response in randomized controlled trials has not been described.

METHODS

We conducted a search of the medical literature following the protocol outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement using MEDLINE, EMBASE and EMBASE Classic, Web of Science, and the Cochrane Central Register of Controlled Trials for all drugs used for the treatment of CIC. Two independent reviewers performed eligibility assessment and data extraction. The mean response rate was examined for the following 2 responder endpoints: (i) greater than or equal to 3 complete spontaneous bowel movements (CSBMs)/wk (≥3 CSBMs/wk responders) and (ii) mean increase of ≥1 CSBM/wk compared with baseline (increase in ≥1 CSBM/wk responders).

RESULTS

A total of 23 placebo-controlled trials met our inclusion criteria and were included in this meta-analysis. The placebo response in CIC trials ranged from 4% to 44%. The magnitude of the placebo response was 13% (95% confidence interval 11%-16%) with the ≥3 CSBM/wk responder endpoint and 28% (95% confidence interval 21%-30%) with the increase of ≥1 in the CSBM responder endpoint. Higher baseline CSBM, older age, and trials with more male participants were significantly associated with a stronger placebo response for both the ≥3 CSBMs/wk endpoint and increase in the ≥1 CSBM/wk endpoint. Trial characteristics such as location (Europe vs Asia/United States) and laxative class (prokinetic vs secretagogue) revealed key differences in the placebo response for both endpoints. The placebo response was not significantly affected by the number of study visits, study duration, year of publication, number of drop outs, or likelihood of receiving active drug.

DISCUSSION

The placebo response in CIC trials ranges from 4% to 44% depending on the endpoint. Modifying factors of the placebo response include multiple subject and trial characteristics.

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

Introduction: Irritable bowel syndrome (IBS) is a complex functional gut disorder that typically manifests in early adult years. More than a third of IBS patients are diagnosed with predominant constipation subtype (IBS-C). This syndrome has a distressing impact on the quality of life and is challenging both for patients and physicians.Areas covered: This review focuses on the pathophysiology of constipation in IBS and presents current management options. It also covers the latest findings that may lead to novel pharmacological options in IBS-C management. The authors intend to highlight the results of published research including abstracts, records from the clinicaltrials.gov database (second and third phases of the study) and information from original FDA documents.Expert opinion: Current therapeutic options for IBS-C treatment are based on linaclotide, lubiprostone, plecanatide, and the reintroduced tegaserod. Drugs present on the market as well as those in pre-clinical development should increase the lower esophageal sphincter pressure, promote gastric motility, accelerate gastric emptying and improve gastro-duodenal coordination. Most significantly, they shall not induce severe side effects.

Non-Cystic Fibrosis-Related Meconium Ileus: GUCY2C-Associated Disease Discovered through Rapid Neonatal Whole-Exome Sequencing

Meconium ileus is caused by cystic fibrosis; however, mutations in the GUCY2C gene also cause this disease. We report non-cystic fibrosis meconium ileus in an infant of non-Middle Eastern origin with compound heterozygous mutations in GUCY2C.

The efficacy of a Persian herbal formulation on functional bloating: A double-blind randomized controlled trial

BACKGROUND

Bloating is a common gastrointestinal complaint which is difficult to treat.

OBJECTIVE

This study investigated the efficacy and compliance of a formulation called KAASER comprised of Trachyspermum ammi (L.) Sprague seed, Zingiber officinale Roscoe. rhizome and Piper nigrum L. berry in the treatment of functional bloating.

DESIGN, SETTING, PARTICIPANTS AND INTERVENTION

A total of 106 patients with functional bloating, between 20 and 50 years of age, participated in this double-blind randomized controlled trial. Patients were divided into 3 parallel groups that received 500 mg of placebo, dimethicone or KAASER, three times a day for 2 weeks.

MAIN OUTCOME MEASURES

The frequency and severity of bloating were primary outcomes, while the frequencies of eructation, defecation, borborygmus and early satiation were secondary outcomes. All parameters were evaluated at the beginning (week 0), and also weeks 2, 4 and 10 of the study, through self-report checklists with a scoring system.

RESULTS

Among the 84 patients who completed the study, the frequency and severity of bloating (P < 0.001), the frequencies of eructation, defecation and borborygmus (P = 0.03) were significantly improved in the group receiving KAASER (36 patients) compared with the dimethicone (35 patients) and placebo (35 patients) groups, during the 3 phases of follow-up. These significant differences persisted through the 2 and 8 weeks of follow-ups after cessation of medication (week 4 and 10). In early satiation, no significant differences were observed among the 3 groups.

CONCLUSION

The results showed that KAASER can be effectively used to treat patients suffering from bloating. Bloating, eructation, defecation and borborygmus in the KAASER group remained significantly improved after 2 and 8 weeks of cessation of medication, making this mechanism an interesting area for further investigation.

TRIAL REGISTRATION

Registration trial IRCT2015100324327N on Iranian Registry of Clinical Trials.

Efficacy of MaZiRenWan, a Chinese Herbal Medicine, in Patients With Functional Constipation in a Randomized Controlled Trial

BACKGROUND & AIMS

The Chinese herbal medicine, MaZiRenWan (MZRW), has been used for more than 2000 years to treat constipation, but it has not been tested in a randomized controlled trial. We performed a trial to evaluate the efficacy and safety of MZRW, compared with the stimulant laxative senna or placebo, for patients with functional constipation (FC).

METHODS

We performed a double-blind, double-dummy, trial of 291 patients with FC based on Rome III criteria, seen at 8 clinics in Hong Kong from June 2013 through August 2015. Patients were observed for 2 weeks and then assigned randomly (1:1:1) to groups given MZRW (7.5 g, twice daily), senna (15 mg daily), or placebo for 8 weeks. Patients were then followed for 8 weeks and evaluated at baseline and weeks 4, 8 (end of treatment), and 16 (end of follow up). Participants recorded information on stool form and frequency, feeling of complete evacuation, and research medication taken. Data on individual bowel symptoms, global symptom improvement, and adverse events were collected. A complete response was defined as an increase ≥1 complete spontaneous bowel movement (CSBM)/week from baseline (the primary outcome). Secondary outcomes included response during the follow-up period, colonic transit, individual and global symptom assessments, quality of life measured with 36-item short form Chinese version, and adverse events.

RESULTS

Although there was no statistically significant difference in proportions of patients with a complete response to MZRW (68%) vs. senna (57.7%) (P = .14) at week 8, there was a statistically significant difference vs. placebo (33.0%) (P < .005). At the 16-week timepoint (after the 8-week follow-up period), 47.4% of patients had a complete response to MZRW, 20.6% had a complete response to senna, and 17.5% had a complete response to placebo (P < .005 for MZRW vs. placebo). The group that received MZRW group also had significant increases in colonic transit and reduced severity of constipation, straining, incomplete evacuation, and global constipation symptoms compared with the groups that received placebo or senna in (P < .05 for all comparisons).

CONCLUSIONS

In a randomized controlled trial of 291 patients with FC, we found MZRW to be well-tolerated and effective in increasing CSBM/week. MZRW did not appear to be more effective than senna and might be considered as an alternative to this drug. ClincialTrials.gov no: NCT01695850.

Bloating and Abdominal Distension: Clinical Approach and Management

Functional abdominal bloating and distension (FABD) are common gastrointestinal complaints, encountered on a daily basis by gastroenterologists and healthcare providers. Functional abdominal bloating is a subjective sensation that is commonly associated with an objective abdominal distension. FABD may be diagnosed as a single entity (the sole or cardinal complaint) or may overlap with other functional gastrointestinal disorders such as functional constipation, irritable bowel syndrome, and functional dyspepsia. The pathophysiology of FABD is not completely understood. Proposed underlying mechanisms include visceral hypersensitivity, behavioral induced abnormal abdominal wall-phrenic reflexes, the effect of poorly absorbed fermentable carbohydrates, and microbiome alterations. Management includes behavioral therapy, dietary interventions, microbiome modulation, and medical therapy. This review presents the current knowledge on the pathophysiology, evaluation, and management of FABD.

Safety and tolerability of linaclotide for the treatment of chronic idiopathic constipation and irritable bowel syndrome with constipation: pooled Phase 3 analysis

BACKGROUND

Linaclotide is approved for treating irritable bowel syndrome with constipation (IBS-C; 290 µg QD) and chronic idiopathic constipation (CIC; 145 µg or 72 µg QD). These analyses aimed to assess linaclotide safety in a large, pooled Phase 3 population.

METHODS

In six randomized controlled trials (RCTs), patients received linaclotide (72 µg, 145 µg, 290 µg) or placebo daily for 12-26 weeks; in two long-term safety (LTS) studies, patients received open-label linaclotide for ≤78 additional weeks. Laboratory values, vital signs, and treatment-emergent adverse events (TEAEs) were assessed.

RESULTS

Overall, 3853 patients received ≥1 dose of linaclotide. The most common TEAE was diarrhea (majority [90.5% in RCTs] mild/moderate). Linaclotide patients experienced 1.1 diarrhea TEAE per patient-year in the RCTs (0.2 in placebo), and 0.3 in the LTS studies. In RCTs, 6.9% linaclotide and 3.0% placebo patients discontinued due to any adverse event (AE); 4.0% linaclotide and 0.3% placebo patients discontinued due to diarrhea. In LTS studies, 9.4% patients discontinued due to any AE, and 3.8% due to diarrhea. Serious AEs (SAEs) were rare and similar across treatment groups; there were no SAEs of diarrhea.

CONCLUSION

These pooled analyses of patients treated for ≤104 weeks confirm linaclotide's overall safety.

Electroacupuncture for Women with Chronic Severe Functional Constipation: Subgroup Analysis of a Randomized Controlled Trial

BACKGROUND

Acupuncture has been found to be effective for treating chronic constipation.

OBJECTIVE

The objective of this exploratory study was to evaluate the efficacy of electroacupuncture (EA) in the subgroup of women with chronic severe functional constipation.

METHODS

This is a subgroup analysis of the multicenter, randomized, sham-acupuncture (SA) controlled trial. The efficacy of 822 (76%) female patients of the 1075 randomized patients with chronic severe functional constipation was evaluated. Patients were randomly assigned to receive 28 sessions of EA or SA over 8 weeks with 12 weeks' follow-up. This study focused on sustained complete spontaneous bowel movements (CSBMs) responders over the 8-week treatment.

RESULTS

The primary outcome which was percentage of the sustained CSBMs responders for the subset of women with severe constipation was significantly higher in the EA group (24.3%) than in the SA group (8.1%) with difference of 13.1% (95%CI, 6.5% to 19.7%; P<0.001). As for the secondary outcomes, responders for ≥9 of 12 weeks of follow-up were higher in the EA group than in the SA group. Additionally, EA had significantly better improvement in mean weekly CSBMs, mean weekly spontaneous bowel movements (SBMs), and mean score changes of stool consistency and straining as well as quality of life of patients. The incidence of adverse events (AEs) related to acupuncture was rare and no statistical significance was found between two groups.

CONCLUSION

EA improved the spontaneity and the completeness of the bowel movement of women with severe functional constipation during 8-week treatment and the effect sustained for 12 weeks after stopping treatment.

Symptomatic Management of Gastroparesis

Gastroparesis is a chronic and debilitating neuromuscular disorder of the upper gastrointestinal tract. Symptoms of gastroparesis include nausea, vomiting, epigastric pain, early satiety, and weight loss. Treating gastroparesis can be difficult. Dietary changes may improve symptoms in patients with mild disease. A variety of medications can be used to treat symptoms of nausea and vomiting, although most have not been subjected to randomized controlled trials and only one is approved by the Food and Drug Administration (metoclopramide). Pain management is essential, as nearly 90% of patients report symptoms of epigastric pain. This article reviews treatment options for symptoms of gastroparesis.

Linaclotide for the treatment of chronic constipation

INTRODUCTION

Chronic constipation (CC) is a common gastrointestinal disorder with limited treatment options. Linaclotide is a potent peptide agonist of the guanylate cyclase-C receptor. This action activates intracellular conversion of guanosine 5-triphosphate to cyclic guanosine monophosphate resulting in the stimulation of intestinal fluid secretion. Linaclotide is a promising new agent for refractory constipation. Areas covered: All published articles regarding the development, clinical efficacy, and safety of linaclotide in treating CC were reviewed. Pharmacodynamics, pharmacokinetics, and metabolism of this secretagogue agent were examined. Clinical studies showed that linaclotide increases the number of spontaneous bowel movements and stool consistency scores. Overall, patients reported relief from abdominal discomfort and severity of constipation. Finally, linaclotide has a good safety profile, with diarrhea being the main side effect. Expert opinion: Linaclotide appears to be a well-tolerated and effective agent for patients with CC, and could be effectively combined with other drugs in patients with refractory constipation. However, data on the efficacy and safety of linaclotide in pediatric patients and in opioid-induced constipation are currently limited and more studies need to be undertaken.

Comparison of acupuncture and other drugs for chronic constipation: A network meta-analysis

The objective of this study was to compare the efficacy and side effects of acupuncture, sham acupuncture and drugs in the treatment of chronic constipation. Randomized controlled trials (RCTs) assessing the effects of acupuncture and drugs for chronic constipation were comprehensively retrieved from electronic databases (such as PubMed, Cochrane Library, Embase, CNKI, Wanfang Database, VIP Database and CBM) up to December 2017. Additional references were obtained from review articles. With quality evaluations and data extraction, a network meta-analysis (NMA) was performed using a random-effects model under a frequentist framework. A total of 40 studies (n = 11032) were included: 39 were high-quality studies and 1 was a low-quality study. NMA showed that (1) acupuncture improved the symptoms of chronic constipation more effectively than drugs; (2) the ranking of treatments in terms of efficacy in diarrhoea-predominant irritable bowel syndrome was acupuncture, polyethylene glycol, lactulose, linaclotide, lubiprostone, bisacodyl, prucalopride, sham acupuncture, tegaserod, and placebo; (3) the ranking of side effects were as follows: lactulose, lubiprostone, bisacodyl, polyethylene glycol, prucalopride, linaclotide, placebo and tegaserod; and (4) the most commonly used acupuncture point for chronic constipation was ST25. Acupuncture is more effective than drugs in improving chronic constipation and has the least side effects. In the future, large-scale randomized controlled trials are needed to prove this. Sham acupuncture may have curative effects that are greater than the placebo effect. In the future, it is necessary to perform high-quality studies to support this finding. Polyethylene glycol also has acceptable curative effects with fewer side effects than other drugs.