A Randomized Phase III Clinical Trial of Plecanatide, a Uroguanylin Analog, in Patients With Chronic Idiopathic Constipation

Managing gastrointestinal manifestations in systemic sclerosis, a mechanistic approach

INTRODUCTION

Systemic sclerosis (SSc) is a connective tissue disease with heterogeneous presentation. Gastrointestinal (GI) complications of SSc are characterized by esophageal reflux, abnormal motility, and microbiome dysbiosis, which impact patient quality of life and mortality. Preventative therapeutics are lacking, with management primarily aimed at symptomatic control.

AREAS COVERED

A broad literature review was conducted through electronic databases and references from key articles. We summarize the physiology of gastric acid production and GI motility to provide context for existing therapies, detail the current understanding of SSc-GI disease, and review GI medications studied in SSc. Finally, we explore new therapeutic options. We propose a management strategy that integrates data on drug efficacy with knowledge of disease pathophysiology, aiming to optimize future therapeutic targets.

EXPERT OPINION

SSc-GI complications remain a challenge for patients, clinicians, and investigators alike. Management presently focuses on treating symptoms and minimizing mucosal damage. Little evidence exists to suggest immunosuppressive therapy halts progression of GI involvement or reverses damage, leaving many unanswered questions about the optimal clinical approach. Further research focused on identifying patients at risk for GI progression, and the underlying mechanism(s) that drive disease will provide opportunities to prevent long-term damage, and significantly improve patient quality of life.

Patient-Reported Outcomes in Disorders of Gut-Brain Interaction

Disorders of gut-brain interaction are characterized by chronic gastrointestinal symptoms in the absence of abnormal endoscopic or radiologic findings or objective biomarkers that can be identified during routine clinical evaluation. The assessment of the symptom pattern and severity, therefore, is the key modality to evaluate the presence, impact, and evolution of these conditions, for both clinical and regulatory purposes. Patient-reported outcomes are structured symptom assessment questionnaires designed to evaluate symptom patterns, quantify severity of symptoms, and evaluate response to treatment at follow-up. This review provides an overview of currently available patient-reported outcomes for evaluating the main disorders of gut-brain interaction, specifically, functional dyspepsia; irritable bowel syndrome; and chronic constipation. It summarizes their content, level of validation for clinical practice and for research, and the regulatory approach to these conditions. Expected future developments and need for further research on patient-reported outcomes for these and other disorders of gut-brain interaction are highlighted.

Polyethylene glycol compared to lactulose for constipation in pregnancy: A randomized controlled trial

OBJECTIVE

To compare polyethylene glycol 4000 versus lactulose in chronic constipation during pregnancy.

METHODS

Women at 28-32 weeks' gestation attending antenatal clinic for routine care were screened using the Rome IV chronic constipation criterion. Eligible women were approached and consented. Participants were randomized to oral polyethylene glycol (10 g/day) or lactulose (10 g/day) for 4 weeks. A bowel movement diary was kept and outcomes using the Patient Assessment of Constipation Symptoms questionnaire (PAC-SYM), Patient Assessment of Constipation Quality of Life questionnaire (PAC-QoL) and Bristol Stool Form Scale (BSFS), which were evaluated at the start and end of the four-week period. Relative risks (RR) were determined for the coprimary outcomes of complete spontaneous bowel movement (CSBM) and PAC-SYM mean score improvement (decrease in score of >1 from the baseline).

RESULTS

A total of 4323 women underwent screening, of which 780 fulfilled the Rome IV criterion, and 360 consented to participate (180 randomized to PEG and lactulose, respectively). Data from 247 women who completed the study were analyzed. CSBM was achieved in 107/124 (86.3%) versus 102/123 (82.9%) (RR 1.04, 95% CI: 0.93-1.16, P = 0.464) for PEG and lactulose trial arms, respectively. PAC-SYM mean score improvement was 62/118 (52.5%) in the PEG arm versus 44/118 (37.3%) in the lactulose arm (RR 1.40, 95% CI: 1.05-1.88). Of secondary outcomes, a significant difference was found in favor of PEG, with respect to PAC-SYM abdominal symptoms subscale, normal stool versus loose stool consistency and side effects of vomiting and diarrhea. After controlling for parity, baseline PAC-SYM, PAC-QoL scores, characteristics different at baseline, only diarrhea and loose stools remained significant.

CONCLUSION

Both PEG 4000 and lactulose are effective laxatives in pregnancy with similar performance after adjusted analysis. Diarrhea and loose stools are less frequently reported with PEG.

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.

Decoding signaling mechanisms: unraveling the targets of guanylate cyclase agonists in cardiovascular and digestive diseases

Soluble guanylate cyclase agonists and guanylate cyclase C agonists are two popular drugs for diseases of the cardiovascular system and digestive systems. The common denominator in these conditions is the potential therapeutic target of guanylate cyclase. Thanks to in-depth explorations of their underlying signaling mechanisms, the targets of these drugs are becoming clearer. This review explains the recent research progress regarding potential drugs in this class by introducing representative drugs and current findings on them.

Fundamental Neurochemistry Review: The role of enteroendocrine cells in visceral pain

While visceral pain is commonly associated with disorders of the gut-brain axis, underlying mechanisms are not fully understood. Dorsal root ganglion (DRG) neurons innervate visceral structures and undergo hypersensitization in inflammatory models. The characterization of peripheral DRG neuron terminals is an active area of research, but recent work suggests that they communicate with enteroendocrine cells (EECs) in the gut. EECs sense stimuli in the intestinal lumen and communicate information to the brain through hormonal and electrical signaling. In that context, EECs are a target for developing therapeutics to treat visceral pain. Linaclotide is an FDA-approved treatment for chronic constipation that activates the intestinal membrane receptor guanylyl cyclase C (GUCY2C). Clinical trials revealed that linaclotide relieves both constipation and visceral pain. We recently demonstrated that the analgesic effect of linaclotide reflects the overexpression of GUCY2C on neuropod cells, a specialized subtype of EECs. While this brings some clarity to the relationship between linaclotide and visceral analgesia, questions remain about the intracellular signaling mechanisms and neurotransmitters mediating this communication. In this Fundamental Neurochemistry Review, we discuss what is currently known about visceral nociceptors, enteroendocrine cells, and the gut-brain axis, and ongoing areas of research regarding that axis and visceral pain.

Non-pharmacological and drug treatment of autonomic dysfunction in multiple system atrophy: current status and future directions

Multiple system atrophy (MSA) is a sporadic, fatal, and rapidly progressive neurodegenerative disease of unknown etiology that is clinically characterized by autonomic failure, parkinsonism, cerebellar ataxia, and pyramidal signs in any combination. Early onset and extensive autonomic dysfunction, including cardiovascular dysfunction characterized by orthostatic hypotension (OH) and supine hypertension, urinary dysfunction characterized by overactive bladder and incomplete bladder emptying, sexual dysfunction characterized by sexual desire deficiency and erectile dysfunction, and gastrointestinal dysfunction characterized by delayed gastric emptying and constipation, are the main features of MSA. Autonomic dysfunction greatly reduces quality of life and increases mortality. Therefore, early diagnosis and intervention are urgently needed to benefit MSA patients. In this review, we aim to discuss the systematic treatment of autonomic dysfunction in MSA, and focus on the current methods, starting from non-pharmacological methods, such as patient education, psychotherapy, diet change, surgery, and neuromodulation, to various drug treatments targeting autonomic nerve and its projection fibers. In addition, we also draw attention to the interactions among various treatments, and introduce novel methods proposed in recent years, such as gene therapy, stem cell therapy, and neural prosthesis implantation. Furthermore, we elaborate on the specific targets and mechanisms of action of various drugs. We would like to call for large-scale research to determine the efficacy of these methods in the future. Finally, we point out that studies on the pathogenesis of MSA and pathophysiological mechanisms of various autonomic dysfunction would also contribute to the development of new promising treatments and concepts.

Plecanatide for the treatment of chronic idiopathic constipation and irritable bowel syndrome with constipation: Post hoc analyses of placebo-controlled trials in adults with severe constipation

BACKGROUND

Patients with chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C) often experience severe symptoms. The current aim was to evaluate plecanatide in adults with CIC or IBS-C with severe constipation.

METHODS

Data were analyzed post hoc from randomized, placebo-controlled trials (CIC [n = 2], IBS-C [n = 2]) of plecanatide 3 mg, 6 mg, or placebo administered for 12 weeks. Severe constipation was defined as no complete spontaneous bowel movements (CSBMs) and an average straining score ≥3.0 (CIC; 5-point scale) or ≥8.0 (IBS-C; 11-point scale) during a 2-week screening. Primary efficacy endpoints were durable overall CSBM responders (CIC: ≥3 CSBMs/week, plus increase from baseline of ≥1 CSBM/week, for ≥9 of 12 weeks, including ≥3 of the last 4 weeks) and overall responders (IBS-C: ≥30% reduction from baseline in abdominal pain and ≥1 CSBM/week increase for ≥6 of 12 weeks).

KEY RESULTS

Severe constipation was observed in 24.5% (646/2639) and 24.2% (527/2176) of CIC and IBS-C populations, respectively. The CIC durable overall CSBM response rate (plecanatide 3 mg, 20.9%; plecanatide 6 mg, 20.2%; placebo, 11.3%) and IBS-C overall response rate (plecanatide 3 mg, 33.0%; plecanatide 6 mg, 31.0%; placebo, 19.0%) were significantly greater with plecanatide versus placebo (p ≤ 0.01 for all). Median time to first CSBM in CIC and IBS-C populations were significantly shorter with plecanatide 3 mg versus placebo (p = 0.01 for both).

CONCLUSIONS AND INFERENCES

Plecanatide was effective in the treatment of severe constipation in adults with CIC or IBS-C.

Pharmacotherapy for gastric and intestinal cramping pain: ‎ current and emerging therapies

INTRODUCTION

Acute gastrointestinal cramping pain (GICP) is a debilitating condition that affects many people worldwide, significantly reducing their quality of life. As such, prompt treatment is crucial.

AREAS COVERED

This article will explore relevant literature from databases such as PubMed, Scopus, Google Scholar, Cochrane Library, and Web of Science. Additionally, we searched ClinicalTrials.gov and the WHO ICTRP database for the latest clinical trials.

EXPERT OPINION

Consensus dictates that antispasmodics such as hyoscine-N-butyl bromide and mebeverine should be the primary treatment for GICP. If these prove ineffective, patients can switch to an antispasmodic with a different mode of action or add acetaminophen/NSAIDs for more severe cases. Currently, several antispasmodics are undergoing clinical trials, including drotaverine, alverine, pinaverium, otilonium bromide, fenoverine, tiropramide, otilonium bromide, trimebutine, and peppermint oil. Well-designed head-to-head studies are necessary to evaluate current antispasmodics' safety, efficacy, pharmacokinetic, and pharmacoeconomics profiles. Recent studies have shown that fixed-dose combinations of antispasmodics + NSAIDs or two different antispasmodics can improve patient compliance and synergistically reduce GICP. Therefore, it is recommended that the global availability and accessibility of these products be enhanced.

Common gastrointestinal drug-drug interactions in geriatrics and the importance of careful planning

INTRODUCTION

Polypharmacy, which uses multiple medications to treat chronic illnesses, is common among elderly patients. However, it can lead to drug interactions, especially with gastrointestinal (GI) medicines that are extensively used. These drug interactions can have severe consequences and pose a significant challenge to healthcare providers. Therefore, it is crucial to identify the underlying mechanisms of these interactions and develop strategies to minimize medication errors.

AREAS COVERED

We analyzed databases on GI illnesses common in older adults, including GERD, peptic ulcer disease, IBS, IBD, constipation, and diarrhea. Our research identified noteworthy drug interactions and utilized major electronic databases such as USFDA, PubMed, Scopus, and Google Scholar until 15 May 202315 May 2023, along with a review of reference lists.

EXPERT OPINION

Aging can affect how the body processes drugs, leading to an increased risk of drug interactions. Therefore, healthcare professionals must carefully evaluate a patient's medical history and health condition to design personalized treatment plans.

American Gastroenterological Association-American College of Gastroenterology Clinical Practice Guideline: Pharmacological Management of Chronic Idiopathic Constipation

INTRODUCTION

Chronic idiopathic constipation (CIC) is a common disorder associated with significant impairment in quality of life. This clinical practice guideline, jointly developed by the American Gastroenterological Association and the American College of Gastroenterology, aims to inform clinicians and patients by providing evidence-based practice recommendations for the pharmacological treatment of CIC in adults.

METHODS

The American Gastroenterological Association and the American College of Gastroenterology formed a multidisciplinary guideline panel that conducted systematic reviews of the following agents: fiber, osmotic laxatives (polyethylene glycol, magnesium oxide, lactulose), stimulant laxatives (bisacodyl, sodium picosulfate, senna), secretagogues (lubiprostone, linaclotide, plecanatide), and serotonin type 4 agonist (prucalopride). The panel prioritized clinical questions and outcomes and used the Grading of Recommendations Assessment, Development, and Evaluation framework to assess the certainty of evidence for each intervention. The Evidence to Decision framework was used to develop clinical recommendations based on the balance between the desirable and undesirable effects, patient values, costs, and health equity considerations.

RESULTS

The panel agreed on 10 recommendations for the pharmacological management of CIC in adults. Based on available evidence, the panel made strong recommendations for the use of polyethylene glycol, sodium picosulfate, linaclotide, plecanatide, and prucalopride for CIC in adults. Conditional recommendations were made for the use of fiber, lactulose, senna, magnesium oxide, and lubiprostone.

DISCUSSION

This document provides a comprehensive outline of the various over-the-counter and prescription pharmacological agents available for the treatment of CIC. The guidelines are meant to provide a framework for approaching the management of CIC; clinical providers should engage in shared decision making based on patient preferences as well as medication cost and availability. Limitations and gaps in the evidence are highlighted to help guide future research opportunities and enhance the care of patients with chronic constipation.

American Gastroenterological Association-American College of Gastroenterology Clinical Practice Guideline: Pharmacological Management of Chronic Idiopathic Constipation

INTRODUCTION

Chronic idiopathic constipation (CIC) is a common disorder associated with significant impairment in quality of life. This clinical practice guideline, jointly developed by the American Gastroenterological Association and the American College of Gastroenterology, aims to inform clinicians and patients by providing evidence-based practice recommendations for the pharmacological treatment of CIC in adults.

METHODS

The American Gastroenterological Association and the American College of Gastroenterology formed a multidisciplinary guideline panel that conducted systematic reviews of the following agents: fiber, osmotic laxatives (polyethylene glycol, magnesium oxide, lactulose), stimulant laxatives (bisacodyl, sodium picosulfate, senna), secretagogues (lubiprostone, linaclotide, plecanatide), and serotonin type 4 agonist (prucalopride). The panel prioritized clinical questions and outcomes and used the Grading of Recommendations Assessment, Development, and Evaluation framework to assess the certainty of evidence for each intervention. The Evidence to Decision framework was used to develop clinical recommendations based on the balance between the desirable and undesirable effects, patient values, costs, and health equity considerations.

RESULTS

The panel agreed on 10 recommendations for the pharmacological management of CIC in adults. Based on available evidence, the panel made strong recommendations for the use of polyethylene glycol, sodium picosulfate, linaclotide, plecanatide, and prucalopride for CIC in adults. Conditional recommendations were made for the use of fiber, lactulose, senna, magnesium oxide, and lubiprostone.

DISCUSSION

This document provides a comprehensive outline of the various over-the-counter and prescription pharmacological agents available for the treatment of CIC. The guidelines are meant to provide a framework for approaching the management of CIC; clinical providers should engage in shared decision making based on patient preferences as well as medication cost and availability. Limitations and gaps in the evidence are highlighted to help guide future research opportunities and enhance the care of patients with chronic constipation.

Randomized Placebo-Controlled Phase 3 Trial of Vibrating Capsule for Chronic Constipation

BACKGROUND & AIMS

Despite therapeutic advances, effective treatments for chronic constipation remain an unmet need. The vibrating capsule is a nonpharmacologic, orally ingested, programmable capsule that vibrates intraluminally to induce bowel movements. We aimed to determine the efficacy and safety of the vibrating capsule in patients with chronic constipation.

METHODS

We conducted a phase 3, double-blind, placebo-controlled trial of patients with chronic constipation, who were randomized to receive either a vibrating or placebo capsule, once daily, 5 days a week for 8 weeks. The primary efficacy end points were an increase of 1 or more complete spontaneous bowel movements per week (CSBM1 responder) or 2 or more CSBMs per week (CSBM2) from baseline during at least 6 of the 8 weeks. Safety analyses were performed.

RESULTS

Among 904 patients screened, 312 were enrolled. A greater percentage of patients receiving the vibrating capsule achieved both primary efficacy end points compared with placebo (39.3% vs 22.1%, P = .001 for CSBM1; 22.7% vs 11.4% P = .008 for CSBM2). Significantly greater improvements were seen with the vibrating capsule for the secondary end points of straining, stool consistency, and quality-of-life measures compared with placebo. Adverse events were mild, gastrointestinal in nature, and similar between groups, except that a mild vibrating sensation was reported by 11% of patients in the vibrating capsule group, but none withdrew from the trial.

CONCLUSIONS

In patients with chronic constipation, the vibrating capsule was superior to placebo in improving bowel symptoms and quality of life. The vibrating capsule was safe and well tolerated. (Clinical trials.gov, Number: NCT03879239).

An Update of Pharmacological Management in Children with Functional Constipation

Functional constipation is a common problem in childhood worldwide and has a great impact on social, physical, and emotional functioning of affected children and their caregivers. It is a clinical diagnosis based on the Rome IV criteria. Non-pharmacological treatment involves education, demystification, lifestyle advice, and toilet training. Pharmacological treatment consists of disimpaction, maintenance treatment, and eventually weaning if possible. Polyethylene glycol is considered as the first choice of laxative for both disimpaction and maintenance treatment. Different osmotic laxatives, stimulant laxatives, lubricants, and enemas are available as alternative pharmacological treatment options. Novel drugs are emerging but evidence to support the widespread application of these drugs in the pediatric population is often lacking and more high-quality research is needed in this field. If children remain symptomatic despite optimal pharmacological treatment, botulinum toxin injections in the anal sphincter can be considered as an alternative, more invasive treatment option. This review provides an update on currently available literature concerning the pharmacologic treatment of functional constipation in children.

Systemic sclerosis gastrointestinal dysmotility: risk factors, pathophysiology, diagnosis and management

Nearly all patients with systemic sclerosis (SSc) are negatively affected by dysfunction in the gastrointestinal tract, and the severity of gastrointestinal disease in SSc correlates with high mortality. The clinical complications of this dysfunction are heterogeneous and include gastro-oesophageal reflux disease, gastroparesis, small intestinal bacterial overgrowth, intestinal pseudo-obstruction, malabsorption and the requirement for total parenteral nutrition. The abnormal gastrointestinal physiology that promotes the clinical manifestations of SSc gastrointestinal disease throughout the gastrointestinal tract are diverse and present a range of therapeutic targets. Furthermore, the armamentarium of medications and non-pharmacological interventions that can benefit affected patients has substantially expanded in the past 10 years, and research is increasingly focused in this area. Here, we review the details of the gastrointestinal complications in SSc, tie physiological abnormalities to clinical manifestations, detail the roles of standard and novel therapies and lay a foundation for future investigative work.

Detecting and treating the protean manifestations of diabetic autonomic neuropathy

The manifestations of diabetic autonomic neuropathy (DAN) are protean and clinically involve multiple systems, including the cardiovascular system, the gastrointestinal system, the genitourinary system as well as the sweat glands (sudomotor dysfunction) and the gallbladder. In addition, cardiac autonomic neuropathy (CAN) is associated with a correctible inability to appreciate and correct hypoglycaemia. While not a clinical problem, pupillary involvement should be the clue and the catalyst to investigate for other manifestations of DAN. This review outlines a practical approach to detecting and investigating the manifestations of DAN. Of particular importance is early detection of cardiovascular involvement where prompt therapy through glycaemic control can decrease the severity of CAN and decelerate the frequency and severity of retinopathy and nephropathy in addition to decreasing cardiovascular events and mortality. CAN also plays a role in accelerating other diabetic complications such as acute ischaemic stroke, heart failure, medial artery calcinosis, foot ulcers, peripheral artery disease and Charcot joints. Many therapies of DAN are available, which should not only decrease morbidity and mortality from DAN, but also improve the patient's quality of life. However, the therapies available are largely symptomatic.

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.

On the Utility of Chemical Strategies to Improve Peptide Gut Stability

Inherent susceptibility of peptides to enzymatic degradation in the gastrointestinal tract is a key bottleneck in oral peptide drug development. Here, we present a systematic analysis of (i) the gut stability of disulfide-rich peptide scaffolds, orally administered peptide therapeutics, and well-known neuropeptides and (ii) medicinal chemistry strategies to improve peptide gut stability. Among a broad range of studied peptides, cyclotides were the only scaffold class to resist gastrointestinal degradation, even when grafted with non-native sequences. Backbone cyclization, a frequently applied strategy, failed to improve stability in intestinal fluid, but several site-specific alterations proved efficient. This work furthermore highlights the importance of standardized gut stability test conditions and suggests defined protocols to facilitate cross-study comparison. Together, our results provide a comparative overview and framework for the chemical engineering of gut-stable peptides, which should be valuable for the development of orally administered peptide therapeutics and molecular probes targeting receptors within the gastrointestinal tract.

Mechanisms of Action of Current Pharmacologic Options for the Treatment of Chronic Idiopathic Constipation and Irritable Bowel Syndrome With Constipation

Multiple therapeutic agents are currently available for the treatment of chronic idiopathic constipation and irritable bowel syndrome with constipation. A better understanding of the mechanism of action of each treatment provides important insights into expected responses and is key to optimizing treatment outcomes. Some constipation treatments, such as stimulant laxatives, may increase bowel movement frequency but are ineffective at relieving, and may even exacerbate, abdominal symptoms. On the contrary, prescription treatments, such as the guanylyl cyclase-C agonists, for example, may improve bowel symptoms and reduce visceral hypersensitivity. This review summarizes the mechanisms of action of commonly used over-the-counter and prescription therapies for chronic idiopathic constipation and irritable bowel syndrome with constipation, outlining how these mechanisms contribute to the efficacy and safety of each treatment option.

Cost of Constipation: A New Look With a Focus on New Medications

GOAL

The study was designed to assess drug costs for constipation therapy and to relate costs to markers of functional status.

BACKGROUND

Secretagogues have been introduced as new agents for the treatment of constipation. Previously published modeling studies suggested that improved productivity lowers the indirect disease burden and balances the higher drug costs.

STUDY

Data were abstracted from the publicly available Medical Expenditure Panel Survey to identify adults with a functional gastrointestinal disorder who received a prescription for laxatives or secretagogues covering >2 days. Demographic data, recorded health care utilization and cost, and markers of functional status were extracted for the years from 2005 to 2017 to determine differences between participants treated with secretagogues or laxatives.

RESULTS

The cohort of 2006 persons was female predominant [67.8%; age: 56.9 (55.8-57.9) years] and spent $92.89 (75.68-110.10) for medications treating constipation. The use of secretagogues (10.3% of the cohort) was the best independent predictor of constipation treatment costs. Using quality of life measures, perceived limitations in activities or work, and absenteeism, there was no difference between participants receiving laxatives and those taking secretagogues.

CONCLUSION

Using survey data designed to be representative of the United States population, the study identified secretagogues as a key cost factor in drug treatment of constipation. The results do not support models suggesting improved role functioning offsets these higher direct expenditures. While prospective comparative studies are needed to more definitively correlate costs with direct or indirect benefits of different agents, limiting the use of more expensive medications to otherwise refractory cases may help to reign in the spiraling health care costs in this country.

Review of the Safety Profiles of Laxatives in Pregnant Women

Chronic constipation is one of the most common complaints seen in the gastroenterology clinic and is particularly prevalent in women. Women who become pregnant may suffer from existing constipation or develop constipation de novo. A thorough understanding of the safety of laxative therapies during pregnancy and the postpartum period is essential to successfully treating these women. Current understanding of the safety of both over the counter and prescription laxatives has not been adequately evaluated. In this article we provide an updated and comprehensive review of the safety profiles of laxatives that are currently used for the treatment of chronic constipation to aid the clinician in risk-benefit discussions with women who are currently or planning to become pregnant.

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.

Colonic Response to Physiological, Chemical, Electrical and Mechanical Stimuli; What Can Be Used to Define Normal Motility?

The colon plays an important functional role in the bacterial fermentation of carbohydrates, transmural exchange of fluid and short-chain fatty acids, and the formation, storage and evacuation of faeces and gaseous contents. Coordinated colonic motor patterns are essential for these functions to occur. Our understanding of human colonic motor patterns has largely come through the use of various forms of colonic manometry catheters, combined with a range of stimuli, both physiological and artificial. These stimuli are used in patients with colonic disorders such as constipation, irritable bowel syndrome and faecal incontinence to understand the pathophysiology mechanisms that may cause the disorder and/or the associated symptoms. However, our understanding of a "normal" colonic response remains poor. This review will assess our understanding of the normal colonic response to commonly used stimuli in short duration studies (<8 hrs) and the mechanisms that control the response.

Chronic Idiopathic Constipation in Adults: A Review on Current Guidelines and Emerging Treatment Options

Chronic idiopathic constipation (CIC) is a common functional bowel disorder characterized by difficult, infrequent, and/or incomplete defecation. It has a great impact on the quality of life and on health care system and represents a heavy economic burden. The diagnosis is based on symptoms, classified by the Rome IV criteria. The aim of this review was to evaluate the current therapeutic guidelines for adult CIC and highlight new emerging treatments. In detail, European, French, Spanish and Korean guidelines have been identified and compared. Osmotic laxatives, and in particular polyethylene glycol, represent the first-line therapeutic approach. Stimulant laxatives are recommended as a second-line therapy. Pelvic floor rehabilitation is recommended in patients with ano-rectal dyssynergia. In patients who fail to improve with pharmacological therapies sacral nerve stimulation is considered as last chance before surgery. Surgical approach has however limited indications in selected cases. Inertia coli refractory to any approach and obstructed defecation are two subtypes which can benefit from surgery. Among emerging agents, prucalopride, a prokinetic agent, is recommended as a second-line treatment in refractory CIC patients. In addition, the secretagogues linaclotide and plecanatide and the bile acid transported inhibitor elobixibat can be effective in patients not responsive to a second-line therapeutic regimen, although they are not worldwide commercially available.

Chronic constipation in adults: Contemporary perspectives and clinical challenges. 2: Conservative, behavioural, medical and surgical treatment

BACKGROUND

Chronic constipation is a prevalent disorder that affects quality of life of patients and consumes resources in healthcare systems worldwide. In clinical practice, it is still considered a challenge as clinicians frequently are unsure as to which treatments to use and when. Over a decade ago, a Neurogastroenterology and Motility journal supplement devoted to the investigation and management of constipation was published (Neurogastroenterol Motil 2009;21(Suppl 2):1). In October 2018, the 3rd London Masterclass, entitled "Contemporary management of constipation" was held. The faculty members of this symposium were invited to write two reviews to present a collective synthesis of talks presented and discussions held during this meeting. The first review addresses epidemiology, diagnosis, clinical associations, pathophysiology, and investigation.

PURPOSE

The present is the second of these reviews, providing contemporary perspectives and clinical challenges regarding behavioral, conservative, medical, and surgical treatments for patients presenting with constipation. It includes a management algorithm to guide clinical practice.

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.

Review of Treatment Options for Irritable Bowel Syndrome with Constipation and Chronic Idiopathic Constipation

Irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) are two common disorders of gut-brain interaction. Affected patients often first present to their primary care providers seeking care for symptoms of constipation, abdominal pain, and bloating, which have a significant impact on their health-related quality of life. These patients often require extensive counseling and reassurance, and knowledge of reliable diagnostic criteria and treatment options is imperative to managing their conditions. Family medicine practitioners, including nurse practitioners and physician assistants, are uniquely qualified to provide a diagnosis and safe, effective management of these disorders. This article reviews the latest evidence and provides practical advice related to diagnosis and management of IBS-C and CIC.

A practical approach to the evaluation and management of gastrointestinal symptoms in patients with systemic sclerosis

The gastrointestinal (GI) tract is the most commonly affected internal organ system in systemic sclerosis (SSc). SSc may lead to impaired function in any region of the GI tract, from the esophagus to the anorectum, which causes significant morbidity as well as mortality in patient subsets. Given the low prevalence of SSc in the community, many rheumatologists may not have a systematic framework for diagnosing or treating the GI complaints in this disease. These practice recommendations aim to summarize and consolidate the current guidelines from the fields of gastroenterology and rheumatology and establish a symptom-based framework for diagnosis and management based on available evidence in the literature. Subject areas that are in need of additional research are also identified.

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.

Plecanatide Is Effective and Safe in the Treatment for Chronic Idiopathic Constipation: Results of a Phase II Trial

BACKGROUND

Many patients with chronic idiopathic constipation (CIC) remain unsatisfied with their treatment options. Plecanatide is a pH-sensitive uroguanylin analog that increases fluid and ion movement into the gastrointestinal lumen, softening stools and encouraging motility, while limiting the risk of diarrhea.

AIMS

The objective of this phase 2 study is to evaluate the safety and efficacy of once-daily oral plecanatide in patients with CIC and identify the most effective dose.

METHODS

A 12-week, multicenter, randomized, double-blind, placebo-controlled, dose-ranging study was conducted in patients aged 18-75 years and diagnosed with CIC based on modified Rome III criteria (< 3 complete spontaneous bowel movements [CSBMs] per week and infrequent loose stools without the use of laxatives). Participants were randomized to placebo or plecanatide 0.3, 1.0, or 3.0 mg. The primary efficacy endpoint was the proportion of overall CSBM responders. Key secondary endpoints included time to first CSBM, change in CSBM and spontaneous bowel movement (SBM) frequency rates, patient-reported outcomes, safety, and tolerability.

RESULTS

Of 951 randomized participants, 946 were included in the modified intent-to-treat population. Plecanatide 0.3 and 3.0 mg significantly increased overall CSBM responder rates compared with placebo (0.3 mg, P = 0.016; 3.0 mg, P = 0.009). Plecanatide was associated with decreased time to first CSBM, significant increases in CSBM and SBM frequency, and decreased patient-reported constipation severity compared with placebo. Diarrhea was the most frequently reported treatment-emergent adverse event.

CONCLUSIONS

Plecanatide is a well-tolerated treatment that relieved the symptoms of CIC with a relatively low incidence of diarrhea.

Evaluation and Treatment of Constipation in the Geriatric Population

Chronic constipation affects one-third of the US population and occurs disproportionately in the elderly and female individuals, increasing in older individuals who are institutionalized. This condition has a significant impact on health care costs and quality of life. Clinicians need to consider primary as well as secondary causes of constipation in elderly individuals because the cause is often multifactorial. Diagnostic algorithms should eliminate red-flag symptoms that may indicate a malignancy but also consider pelvic floor dysfunction, which is more common in this age group. An appropriate treatment plan is tailored to the severity of the patient's symptoms.

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.

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.

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.

Constipation and Fecal Incontinence in the Elderly

PURPOSE OF REVIEW

To review the epidemiology, pathogenesis, clinical features, and management of primary constipation and fecal incontinence in the elderly.

RECENT FINDINGS

Among elderly people, 6.5%, 1.7%, and 1.1% have functional constipation, constipation-predominant IBS, and opioid-induced constipation. In elderly people, the number of colonic enteric neurons and smooth muscle functions is preserved; decreased cholinergic function with unopposed nitrergic relaxation may explain colonic motor dysfunction. Less physical activity or dietary fiber intake and postmenopausal hormonal therapy are risk factors for fecal incontinence in elderly people. Two thirds of patients with fecal incontinence respond to biofeedback therapy. Used in combination, loperamide and biofeedback therapy are more effective than placebo, education, and biofeedback therapy. Vaginal or anal insert devices are another option. In the elderly, constipation and fecal incontinence are common and often distressing symptoms that can often be managed by addressing bowel disturbances. Selected diagnostic tests, prescription medications, and, infrequently, surgical options should be considered when necessary.

An overview of interventions for constipation in adults

INTRODUCTION

The increasing global prevalence of the symptoms of constipation adversely affects the quality of life (QOL) of symptomatic patients. An acceptable universal definition of constipation does not exist and a detailed history taking form each patient with various complaints including stool consistency, sensing of incomplete evacuation or a manual need to assist evacuation is required. Complexity of obtaining etiologic diagnosis and the wide range of therapeutic options can mislead physicians in choosing correct treatment.

AREAS COVERED

This review, considers the pathophysiology of constipation and the diagnostic approach to identify the etiology of constipation. Available interventions including non-pharmacological, pharmacological, and invasive methods such as acupuncture and surgical management are discussed. This review utilized on PubMed, Google Scholar, Scopus, and clinicaltrials.gov to search for studies and reviews published between 2000 and 2020.

EXPERT COMMENTARY

Constipation necessitates careful considerations to detect the exact pathophysiology. Medical history, focused physical assessments, and selected diagnostic tests help choosing the right management. Non-pharmacological methods are beneficial in most of the cases. If a satisfactory response is not achieved, over the counter or prescribed medications are available. Options for patients who failed to respond to available medications are addressed in this review.

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.

Influence of sleep disorders on anxiety and depression and quality of life in elderly patients with chronic functional constipation

BACKGROUND

With the changes of dietary structure and lifestyles, the incidence of chronic constipation is gradually increasing. Sleep disorders increase gastrointestinal symptoms and are a risk factor for anxiety and depression. The purpose of this study was to explore the influence of sleep disorders on anxiety and depression and quality of life in elderly patients with chronic functional constipation, so as to provide an objective basis for the treatment of elderly patients with chronic functional constipation.

AIM

To investigate the effects of sleep disorders on anxiety and depression and quality of life in elderly patients with chronic functional constipation.

METHODS

A total of 126 elderly patients with chronic functional constipation admitted to our hospital from March 2017 to September 2019 were selected as the study subjects. They were divided into a sleep disorder group and a normal sleep group according to whether they had a sleep disorder. All patients underwent assessments using the constipation scoring system (CSS), patient assessment of constipation-symptoms (PAS-SYM) questionnaire, sleep quality assessment, self-rating anxiety scale (SAS), self-rating depression scale (SDS), and a quality of life scale.

RESULTS

In the sleep disorder group, the CSS score was 19.63 ± 3.36, the PAS-SYM score was 1.59 ± 0.52, the SAS score was 58.92 ± 6.72, and the SDS score was 57.74 ± 6.38, all of which were significantly higher than those of the normal sleep group (P < 0.05). The scores of social function, emotional score, physical role, physical health, mental health, and total health in the sleep disorder group were 71.56 ± 3.38, 75.89 ± 2.95, 76.86 ± 2.92, 80.25 ± 3.35, 78.36 ± 3.65, and 76.19 ± 2.56, respectively, all of which were significantly lower than those of the normal sleep group (P < 0.05). CSS scores, PAS-SYM scores, and total scores were positively correlated with SAS and SDS scores (P < 0.05). The scores of the six dimensions in SF-36 were negatively correlated with SAS and SDS scores (P < 0.05).

CONCLUSION

Sleep disorders, anxiety, and depression may be important factors affecting the clinical symptoms and quality of life of elderly patients with chronic functional constipation.

Mechanisms, Evaluation, and Management of Chronic Constipation

With a worldwide prevalence of 15%, chronic constipation is one of the most frequent gastrointestinal diagnoses made in ambulatory medicine clinics, and is a common source cause for referrals to gastroenterologists and colorectal surgeons in the United States. Symptoms vary among patients; straining, incomplete evacuation, and a sense of anorectal blockage are just as important as decreased stool frequency. Chronic constipation is either a primary disorder (such as normal transit, slow transit, or defecatory disorders) or a secondary one (due to medications or, in rare cases, anatomic alterations). Colonic sensorimotor disturbances and pelvic floor dysfunction (such as defecatory disorders) are the most widely recognized pathogenic mechanisms. Guided by efficacy and cost, management of constipation should begin with dietary fiber supplementation and stimulant and/or osmotic laxatives, as appropriate, followed, if necessary, by intestinal secretagogues and/or prokinetic agents. Peripherally acting μ-opiate antagonists are another option for opioid-induced constipation. Anorectal tests to evaluate for defecatory disorders should be performed in patients who do not respond to over-the-counter agents. Colonic transit, followed if necessary with assessment of colonic motility with manometry and/or a barostat, can identify colonic dysmotility. Defecatory disorders often respond to biofeedback therapy. For specific patients, slow-transit constipation may necessitate a colectomy. No studies have compared inexpensive laxatives with newer drugs with different mechanisms. We review the mechanisms, evaluation, and management of chronic constipation. We discuss the importance of meticulous analyses of patient history and physical examination, advantages and disadvantages of diagnostic testing, guidance for individualized treatment, and management of medically refractory patients.

Analysis of correlation of sleep disturbance with anxiety, depression, and quality of life in elderly patients with chronic constipation based on "brain-gut axis" theory

BACKGROUND

Sleep disorders can increase the incidence of gastrointestinal symptoms, and a long-term decline in sleep quality is a risk factor for anxiety and depression. This study, based on the "brain-gut axis" theory, explored whether sleep disorder aggravates the clinical manifestations of elderly patients with chronic constipation and whether it affects their psychological mood and quality of life.

AIM

To explore the correlation of sleep disturbance with anxiety, depression, and quality of life in elderly patients with chronic constipation based on the "brain-gut axis" theory.

METHODS

One hundred and twenty-six elderly patients with chronic constipation who were hospitalized at our hospital from March 2017 to September 2019 were selected as the study subjects. The constipation scoring system (CSS), symptom self-rating questionnaire, sleep quality assessment, anxiety and depression scales, and quality of life scale were administered to all patients.

RESULTS

The sleep disorder group had a CSS score of 19.63 ± 3.36, patient assessment of constipation symptom (PAS-SYM) score of 1.59 ± 0.52, self-rating anxiety scale (SAS) score of 58.92 ± 6.72, and self-rating depression scale (SDS) score of 57.74 ± 6.38, which were significantly higher than those of the normal sleep group (P < 0.05). In the sleep disorder group, the scores of social function, mood, physical role, physical health, mental health, and overall health were 71.56 ± 3.38, 75.89 ± 2.95, 76.86 ± 2.92, 80.25 ± 3.35, 78.36 ± 3.65, and 76.19 ± 2.56, respectively, all of which were significantly lower than those of the normal sleep group (P < 0.05). CSS score, scores of all dimensions of PAC-SYM score, and PAC-SYM total score were positively correlated with SAS and SDS scores (P < 0.05). The scores of the six dimensions of SF-36 were negatively correlated with SAS and SDS scores (P < 0.05).

CONCLUSION

The brain-gut axis is the bridge between the gastrointestinal tract and the brain. Sleep disorders, anxiety, and depression may be important factors affecting the clinical symptoms of elderly patients with chronic constipation, and affect their quality of life.

Abnormal Uroguanylin Immunoreactive Cells Density in the Duodenum of Patients with Diarrhea-Predominant Irritable Bowel Syndrome Changes following Fecal Microbiota Transplantation

Altered densities of enteroendocrine cells play an important role in patients with irritable bowel syndrome (IBS). Uroguanylin activates guanylate cyclase-C to regulate intestinal electrolyte and water transport. Aim. To quantify uroguanylin immunoreactive cells density in the duodenum of diarrhea-predominant IBS (IBS-D) patients compared to controls and to investigate the effect of fecal microbiota transplantation (FMT) on these cell densities. Method. Twelve patients with IBS-D according to Rome III criteria were included. The cause was identified as post infectious (PI, n = 6) or idiopathic (n = 6). They completed the IBS-symptom questionnaire before and 3 weeks after FMT. Thirty grams of fresh feces donated from healthy relatives were diluted with 60 ml normal saline and instilled via endoscope into the duodenum. Biopsies were taken from the patients' duodenum before and 3 weeks after FMT. Duodenal biopsies taken from eight healthy controls were also included. The biopsies were immunostained for uroguanylin and quantified using computerized image analysis. Results. Uroguanylin immunoreactive cells were found both in duodenal villi and crypts in both controls and IBS-D patients. The densities of uroguanylin immunoreactive cells were significantly lower in the villi (P < 0.0001) and higher in the crypts (P < 0.0001) for the patients than the controls. Following FMT, the densities of uroguanylin immunoreactive cells for the total group and idiopathic subgroup decreased significantly in the duodenal crypts (P = 0.049 and 0.04, respectively) but not in the villi. No significant changes were shown in the PI-IBS subgroups. The cells density in only the crypts correlated with diarrhea (r = 0.97, P = 0.001) and bloating (r = -0.91, P = 0.01) in the PI-IBS subgroup before FMT and with abdominal pain (r = 0.63, P = 0.03) in the total group of IBS-D patients after FMT. Conclusion. Altered uroguanylin immunoreactive cells density was found in IBS-D patients compared to controls. Changes in these cells density following FMT correlated with IBS symptoms (diarrhea, bloating, and abdominal pain).

Plecanatide for the treatment of constipation-predominant irritable bowel syndrome

Introduction: As an analogue of uroguanylin plecanatide binds to the Guanylate Cyclase-C receptor activating fluid and ion secretion in the small intestine with the same pH-dependent binding kinetics as the natural ligand. Plecanatide has been FDA approved as safe and effective for the indications of Chronic Idiopathic Constipation (CIC) and Irritable Bowel Syndrome with Constipation (IBS-C).Areas covered: All clinical trial results supporting approval of plecanatide in IBS-C are reported, evaluated and interpreted in the context of the complex pathophysiology of functional diseases and the barriers that must be overcome for appropriate protocol design and conduct.Expert opinion: The Expert Opinion section discusses safety and efficacy of plecanatide for IBS-C. Broader consideration of some of the inherent challenges in understanding and treating functional gastrointestinal disorders includes: 1. the difficulty of understanding diseases with complex pathophysiology that clinically present with a few simple symptoms, 2. exploring the pathophysiology of functional diseases using pharmacophysiology, 3. value of 'Set Theory' in the evaluation of complex clinical data and 4. physiologic and pathophysiologic insight gained by evaluation 'physiologic redundancy' and 'conservation of function'.

An approach to the diagnosis and management of Rome IV functional disorders of chronic constipation

Introduction: Chronic constipation is highly prevalent, affecting between 10% and 15% of the population. The Rome IV criteria categorizes disorders of chronic constipation into four subtypes: (a) functional constipation, (b) irritable bowel syndrome with constipation, (c) opioid-induced constipation, and (d) functional defecation disorders, including inadequate defecatory propulsion and dyssynergic defecation. The initial management approach for these disorders is similar, focusing on diet, lifestyle and the use of standard over-the-counter laxatives. If unsuccessful, further therapy is tailored according to subtype.Areas covered: This review covers the definition, epidemiology, diagnostic criteria, investigations and management of the Rome IV disorders of chronic constipation.Expert opinion: By adopting a logical step-wise approach toward the diagnosis of chronic constipation and its individual subtypes, clinicians have the opportunity to tailor therapy accordingly and improve symptoms, quality of life, and patient satisfaction.

Management of functional constipation in children and adults

Functional constipation is common in children and adults worldwide. Functional constipation shows similarities in children and adults, but important differences also exist regarding epidemiology, symptomatology, pathophysiology, diagnostic workup and therapeutic management. In children, the approach focuses on the behavioural nature of the disorder and the initial therapeutic steps involve toilet training and laxatives. In adults, management focuses on excluding an underlying cause and differentiating between different subtypes of functional constipation - normal transit, slow transit or an evacuation disorder - which has important therapeutic consequences. Treatment of adult functional constipation involves lifestyle interventions, pelvic floor interventions (in the presence of a rectal evacuation disorder) and pharmacological therapy. When conventional treatments fail, children and adults are considered to have intractable functional constipation, a troublesome and distressing condition. Intractable constipation is managed with a stepwise approach and in rare cases requires surgical interventions such as antegrade continence enemas in children or colectomy procedures for adults. New drugs, including prokinetic and prosecretory agents, and surgical strategies, such as sacral nerve stimulation, have the potential to improve the management of children and adults with intractable functional constipation.