Examining Balloon Expulsion Testing as an Office-Based, Screening Test for Dyssynergic Defecation: A Systematic Review and Meta-Analysis

Enhancing standardization in anorectal manometry testing: the impact of a national position paper

BACKGROUND

The 2019 International Anorectal Physiology Working Group published the 'London Classification', providing recommendations for anorectal manometry (ARM) and balloon expulsion testing (BET). Despite this, the extent of guideline adoption in clinical settings was unclear. This study aimed to evaluate ARM and BET practices across Israel, identify deviations from these international guidelines, and measure the impact of a newly instated national position paper.

METHODS

In late 2020, gastroenterologists from 95% of Israeli centers performing ARM responded to a comprehensive 61-item survey. The survey highlighted discrepancies with international standards, prompting the formation of a national task force. This task force drafted a position paper incorporating international recommendations, followed by an educational course on ARM and BET. A subsequent survey assessed practice changes 1 year later.

RESULTS

Initial findings showed considerable variation in practices, including inconsistent application of the London classification, lack of standardized reference values, selective reporting on parameters like anal squeeze pressure, and differences in ARM and BET methodologies. Following the introduction of the position paper, 87% of centers altered their practices to include standardized reporting, consistent use of normal values, and uniform execution of tests like the rectoanal inhibitory reflex. Despite these improvements, variations in BET techniques persisted, particularly regarding balloon use and patient positioning.

CONCLUSION

The implementation of a national position paper and subsequent educational initiatives markedly enhanced the standardization of ARM and BET procedures in Israel, demonstrating the value of targeted educational and policy interventions in harmonizing medical practices with established international guidelines.

Prevalence and Clinical Impact of the London Classification: A Prospective, International, Multicenter Study From the Lower Gastrointestinal International Consortium (LoGIC)

INTRODUCTION

The London classification provides standardization for characterization of disorders of anorectal function, although prevalences and clinical impact of these disorders are unclear.

METHODS

An international research consortium was established, including 5 specialist centers. Prospective data were collected in consecutive adults referred for refractory chronic constipation (CC), fecal incontinence (FI), or coexistent CC/FI over 18 months. Patients completed a standardized clinical questionnaire and underwent anorectal physiology tests, which were performed and interpreted using uniform methodology. The prevalence of the London classification was compared between symptom groups (CC, FI, and coexistent CC/FI), equipment types, and sites. Clinical impact was assessed using Cleveland Clinic Constipation and St. Marks Incontinence Scores.

RESULTS

Of 1,012 included patients (85.6% women), 30.5% had self-reported CC, 33.2% had FI, and 36.3% had coexistent CC/FI. Rectoanal areflexia was uncommon (3.1%). Disorders of anal tone/contractility (CC: 45.0%; FI: 68.5%; coexistent CC/FI: 63.8%; P < 0.0001) and disorders of rectal sensation (major findings: rectal hyposensitivity, CC: 10.0%; FI: 5.0%; coexistent CC/FI: 11.1%; P = 0.018; rectal hypersensitivity, CC: 3.8%; FI: 9.0%; coexistent CC/FI: 4.9%; P = 0.025) varied between the symptom groups and were associated with symptom severity. Most disorders of rectoanal coordination were found in similar proportions across the symptom groups and were not associated with the severity of CC (median Cleveland Clinic Constipation Score 10-14 in all groups). Prevalences of some disorders differed between equipment types (specifically balloon expulsion test).

DISCUSSION

This prospective multicenter study provides information on the prevalence and clinical impact of the London classification and will guide refinement of the current London classification.

Use of a footstool improves rectal balloon expulsion in some patients with defecatory disorders

BACKGROUND

Whether patients with defecatory disorders (DDs) with favorable response to a footstool have distinctive anorectal pressure characteristics is unknown. We aimed to identify the clinical phenotype and anorectal pressure profile of patients with DDs who benefit from a footstool.

METHODS

This is a retrospective review of patients with high resolution anorectal manometry (HR-ARM) and balloon expulsion test (BET) from a tertiary referral center. BET was repeated with a 7-inch-high footstool in those who failed it after 120 s. Data were compared among groups with respect to BET results.

KEY RESULTS

Of the 667 patients with DDs, a total of 251 (38%) had failed BET. A footstool corrected BET in 41 (16%) of those with failed BET. Gender-specific differences were noted in anorectal pressures, among patients with and without normal BET, revealing gender-based nuances in pathophysiology of DDs. Comparing patients who passed BET with footstool with those who did not, the presence of optimal stool consistency, with reduced instances of loose stools and decreased reliance on laxatives were significant. Additionally, in women who benefited from a footstool, lower anal pressures at rest and simulated defecation were observed. Independent factors associated with a successful BET with a footstool in women included age <50, Bristol 3 or 4 stool consistency, lower anal resting pressure and higher rectoanal pressure gradient.

CONCLUSION & INFERENCES

Identification of distinctive clinical and anorectal phenotype of patients who benefited from a footstool could provide insight into the factors influencing the efficacy of footstool utilization and allow for an individualized treatment approach in patients with DDs.

Diagnosis of Chronic Constipation

Patients with chronic constipation (CC) usually complain of mild to severe symptoms, including hard or lumpy stools, straining, a sense of incomplete evacuation after a bowel movement, a feeling of anorectal blockage, the need for digital maneuver to assist defecation, or reduced stool frequency. In clinical practice, healthcare providers need to check for 'alarm features' indicative of a colonic malignancy, such as bloody stools, anemia, unexplained weight loss, or new-onset symptoms after 50 years of age. In the Seoul Consensus on the diagnosis and treatment of chronic constipation, the Bristol stool form scale, colonoscopy, and digital rectal examination are useful for objectively evaluating the symptoms and making a differential diagnosis of the secondary cause of constipation. If patients with CC improve to lifestyle modification or first-line therapies, the effort to determine the subtypes of CC is usually not considered. On the other hand, if conventional therapeutic strategies fail, diagnostic testing needs to be considered to distinguish between the different subtypes of functional constipation (normal-transit constipation, slow transit constipation, or defecatory disorder) because these subtypes of constipation have different therapeutic implications and a correct diagnosis is critical. In the Seoul consensus, physiological testing is recommended for patients with functional constipation who have failed to respond to treatment with available laxatives (for a minimum of 12 weeks and recommended a therapeutic regimen) or who are strongly suspected of having a defecatory disorder. The Seoul consensus contains statements of physiological testing, including balloon expulsion test, anorectal manometry, defecography, and colon transit time.

Increased Grades of Rectal Intussusception: Role of Decline in Pelvic Floor Integrity and Association With Dyssynergic Defecation

INTRODUCTION

The natural history of rectal intussusception (RI) is poorly understood. We hypothesized that decline in pelvic floor integrity and function leads to increasing RI grades.

METHODS

Retrospective analysis of a registry of patients with defecatory disorders with high-resolution anorectal manometry and magnetic resonance defecography was performed. Association of risk factors on increasing RI grades was assessed using logistic regression.

RESULTS

Analysis included a total of 238 women: 90 had no RI, 43 Oxford 1-2, 49 Oxford 3, and 56 Oxford 4-5. Age ( P = 0.017), vaginal delivery ( P = 0.008), and prior pelvic surgery ( P = 0.032) were associated with increased Oxford grades. Obstructive defecation symptoms and dyssynergic defecation were observed at relatively high rates across groups. Increased RI grades were associated with less anal relaxation at simulated defecation yet, higher rates of normal balloon expulsion ( P < 0.05), linked to diminished anal sphincter. Indeed, increased RI grades were associated with worsening fecal incontinence severity, attributed to higher rates of anal hypotension. Levator ani laxity, defined by increased levator hiatus length and its excessive descent at straining, was associated with increasing RI grades, independent of age, history of vaginal delivery, and pelvic surgeries and could independently predict increased RI grades. Concurrent anterior and posterior compartments, and visceral prolapse were associated with higher Oxford grades.

DISCUSSION

Our data suggest that decline in pelvic floor integrity with abnormal levator ani laxity is associated with increased RI grades, a process that is independent of age, history of vaginal deliveries, and/or pelvic surgeries, and perhaps related to dyssynergic defecation.

Diagnostic value of balloon expulsion test and anorectal manometry in patients with constipation: a systematic review and meta-analysis

This study aims to compare the diagnostic value of balloon expulsion test and anorectal manometry in patients with constipation through meta-analysis. Databases, encompassing PubMed, EMBASE, Cochrane Library, Web of Science, etc. were searched for all English publications on the diagnosis of constipation using balloon expulsion test and anorectal manometry. The publication date was restricted from the inception of the databases until December 2022. Data analysis was carried out utilizing Stata 15.0 and Meta-Disc 1.4 software. Thirteen studies involving 2171 patients with constipation were included. According to the meta-analysis, the balloon expulsion test showed a pooled sensitivity of 0.75 (95% CI: 0.72-0.77), a pooled specificity (Spe) of 0.67 (95% CI: 0.62-0.72), a pooled positive likelihood ratio (+LR) of 3.24 (95% CI: 1.53-6.88), a pooled negative likelihood ratio (-LR) 0.35 (95% CI: 0.23-0.52) and a pooled diagnostic odds ratio (DOR) of 9.47 (95% CI: 3.27-27.44). For anorectal manometry, the pooled Sen, Spe, +LR, -LR and DOR were 0.74 (95% CI: 0.72-0.76), 0.73 (95% CI: 0.70-0.76), 2.69 (95% CI: 2.18-3.32), 0.35 (95% CI: 0.28-0.43), and 8.3 (95% CI: 5.4-12.75), respectively. The area under the summary receiver operating characteristic curve areas for balloon expulsion test and anorectal manometry were 0.8123 and 0.8088, respectively, with no statistically significant disparity (Z = -0.113, P > 0.05). Both the balloon expulsion test and anorectal manometry demonstrate comparable diagnostic performance, each offering unique advantages. These diagnostic procedures hold significance in the diagnosis of constipation.

High-resolution anorectal manometry for diagnosing obstructed defecation syndrome associated with moderate rectocele compared to healthy individuals

BACKGROUND

Few studies have investigated healthy female individuals (HFI) and those with obstructed defecation syndrome associated with moderate rectocele in women (MRW), identified using three-dimensional high-resolution anorectal manometry (3D HRAM) parameters that correlate with age stratification.

OBJECTIVE

We aimed to explore the clinical diagnostic values of the MRW and HFI groups using 3D HRAM parameters related to age stratification.

METHODS

A prospective non-randomized controlled trial involving 128 cases from the MRW (treatment group, 68 cases) and HFI (control group, 60 cases) groups was conducted using 3D HRAM parameters at Tianjin Union Medical Center between January 2017 and June 2022, and patients were divided into two subgroups based on their ages: the ≥50 and < 50 years subgroups.

RESULTS

Multivariate binary logistic regression analysis showed that age (P = 0.024) and rectoanal inhibitory reflex (P = 0.001) were independent factors affecting the disease in the MRW group. Compared to the HFI group, the receiver operating characteristic (ROC) curve demonstrated that the 3D HRAM parameters exhibited a higher diagnostic value for age (Youden index = 0.31), urge to defecate (Youden index = 0.24), and rectoanal pressure differential (Youden index = 0.21) in the MRW group.

CONCLUSIONS

Compared to the HFI group, the ROC curve of the 3D HRAM parameters suggests that age, urge to defecate, and rectoanal pressure differential in the MRW group have a significant diagnostic value. Because the Youden index is lower, 3D HRAM cannot be considered the gold standard method for diagnosing MRW.

Optimizing the Utility of Anorectal Manometry for Diagnosis and Therapy: A Roundtable Review and Recommendations

BACKGROUND & AIMS

Anorectal manometry (ARM) is a comprehensive diagnostic tool for evaluating patients with constipation, fecal incontinence, or anorectal pain; however, it is not widely utilized for reasons that remain unclear. The aim of this roundtable discussion was to critically examine the current clinical practices of ARM and biofeedback therapy by physicians and surgeons in both academic and community settings.

METHODS

Leaders in medical and surgical gastroenterology and physical therapy with interest in anorectal disorders were surveyed regarding practice patterns and utilization of these technologies. Subsequently, a roundtable was held to discuss survey results, explore current diagnostic and therapeutic challenges with these technologies, review the literature, and generate consensus-based recommendations.

RESULTS

ARM identifies key pathophysiological abnormalities such as dyssynergic defecation, anal sphincter weakness, or rectal sensory dysfunction, and is a critical component of biofeedback therapy, an evidence-based treatment for patients with dyssynergic defecation and fecal incontinence. Additionally, ARM has the potential to enhance health-related quality of life and reduce healthcare costs. However, it has significant barriers that include a lack of education and training of healthcare providers regarding the utility and availability of ARM and biofeedback procedures, as well as challenges with condition-specific testing protocols and interpretation. Additional barriers include understanding when to perform, where to refer, and how to use these technologies, and confusion over billing practices.

CONCLUSIONS

Overcoming these challenges with appropriate education, training, collaborative research, and evidence-based guidelines for ARM testing and biofeedback therapy could significantly enhance patient care of anorectal disorders.

Differential Findings on Anorectal Manometry in Patients with Parkinson's Disease and Defecatory Dysfunction

Introduction

Gastrointestinal dysfunction, particularly constipation, is among the most common non-motor manifestations in Parkinson's Disease (PD). We aimed to identify high-resolution anorectal manometry (HR-ARM) abnormalities in patients with PD using the London Classification.

Methods

We conducted a retrospective review of all PD patients at our institution who underwent HR-ARM and balloon expulsion test (BET) for evaluation of constipation between 2015 and 2021. Using age and sex-specific normal values, HR-ARM recordings were re-analyzed and abnormalities were reported using the London Classification. A combination of Wilcoxon rank sum and Fisher's exact test were used.

Results

36 patients (19 women) with median age 71 (interquartile range [IQR]: 69-74) years, were included. Using the London Classification, 7 (19%) patients had anal hypotension, 17 (47%) had anal hypocontractility, and 3 women had combined hypotension and hypocontractility. Anal hypocontractility was significantly more common in women compared to men. Abnormal BET and dyssynergia were noted in 22 (61%) patients, while abnormal BET and poor propulsion were only seen in 2 (5%). Men had significantly more paradoxical anal contraction and higher residual anal pressures during simulated defecation, resulting in more negative recto-anal pressure gradients. Rectal hyposensitivity was seen in nearly one third of PD patients and comparable among men and women.

Conclusion

Our data affirms the high prevalence of anorectal disorders in PD. Using the London Classification, abnormal expulsion and dyssynergia and anal hypocontractility were the most common findings in PD. Whether the high prevalence of anal hypocontractility in females is directly related to PD or other confounding factors will require further research.

Utility of Anorectal Testing to Predict Outcomes With Pelvic Floor Physical Therapy in Chronic Constipation: Pragmatic Trial

BACKGROUND & AIMS

We performed a clinical trial that aimed to inform the clinical utility of anorectal manometry (ARM) and balloon expulsion time (BET) as up-front tests to predict outcomes with community-based pelvic floor physical therapy as the next best step to address chronic constipation after failing an empiric trial of soluble fiber supplementation or osmotic laxatives.

METHODS

We enrolled 60 treatment-naïve patients with Rome IV functional constipation failing 2 weeks of soluble fiber supplementation or osmotic laxatives. All patients underwent ARM/BET (London protocol) followed by community-based pelvic floor physical therapy. Outcomes were assessed at baseline and 12 weeks. The primary end point was clinical response (Patient Assessment of Constipation-Symptoms instrument).

RESULTS

Fifty-three patients completed pelvic rehabilitation and the post-treatment questionnaire. Contemporary frameworks define dyssynergia on balloon expulsion time and dyssynergic patterns (ARM), but these parameters did not inform clinical outcomes (area under the curve [AUC], <0.6). Squeeze pressure (>192.5 mm Hg on at least 1 of 3 attempts; sensitivity, 47.6%; specificity, 83.9%) and limited squeeze duration (inability to sustain 50% of squeeze pressure for >20 seconds; sensitivity, 71.4%; specificity, 58.1%) were the strongest predictors of clinical outcomes. Combining BET with squeeze duration (BET greater than 6.5 seconds and limited squeeze duration) improved predictive accuracy (AUC, 0.75; 95% CI, 0.59-0.90). BET poorly predicted outcomes as a single test (AUC, 0.54; 95% CI, 0.38-0.69).

CONCLUSIONS

Using ARM to evaluate squeeze profiles, rather than dyssynergia, appears useful to screen patients with chronic constipation for up-front pelvic floor physical therapy based on likelihood of response. BET appears noninformative as a single screening test (ClinicalTrials.gov: NCT04159350).

An Office-Based, Point-of-Care Test Predicts Treatment Outcomes With Community-Based Pelvic Floor Physical Therapy in Patients With Chronic Constipation

BACKGROUND & AIMS

Rectal evacuation disorders are common among constipated patients. We aimed to evaluate the accuracy of an investigational point-of-care test (rectal expulsion device [RED]) to predict outcomes with community-based pelvic floor physical therapy.

METHODS

We enrolled patients meeting Rome IV criteria for functional constipation failing fiber/laxatives for more than 2 weeks. RED was inserted and self-inflated, and then time-to-expel was measured in a left lateral position. All patients underwent empiric community-based pelvic floor physical therapy in routine care with outcomes measured at 12 weeks. The primary end point was global clinical response (Patient Assessment of Constipation Symptoms score reduction, >0.75 vs baseline). Secondary end points included improvement in health-related quality-of-life (Patient Assessment of Constipation Quality of Life score reduction, >1.0) and complete spontaneous bowel movement frequency (Food and Drug Administration complete spontaneous bowel movement responder definition).

RESULTS

Thirty-nine patients enrolled in a feasibility phase to develop the use-case protocol. Sixty patients enrolled in a blinded validation phase; 52 patients (mean, 46.9 y; 94.2% women) were included in the intention-to-treat analysis. In the left lateral position, RED predicted global clinical response (generalized area under the curve [gAUC], 0.67; 95% CI, 0.58-0.76]), health-related quality-of-life response (gAUC, 0.67; 95% CI, 0.58-0.77; P < .001), and complete spontaneous bowel movement response (gAUC, 0.63; 95% CI, 0.57-0.71; P < .001). As a screening test, a normal RED effectively rules out evacuation disorders (expected clinical response, 8.9%; P = .042). Abnormal RED in the left lateral position (defined as expulsion within 5 seconds or >120 seconds) predicted 48.9% clinical response to physical therapy. A seated maneuver enhanced the likelihood of clinical response (71.1% response with seated RED retained >13 seconds) but likely is unnecessary in most settings.

CONCLUSIONS

RED offers an opportunity to disrupt the paradigm by offering a personalized approach to managing chronic constipation in the community (Clinicaltrials.gov: NCT04159350).

Can a Defecation Posture Modifying Device Correct an Abnormal Balloon Expulsion Test in Chronically Constipated Patients?

Evacuation disorders are common among chronically constipated (CC) patients who fail to respond to laxatives and are typically diagnosed by anorectal manometry (ARM) and/or balloon expulsion testing (BET).^1,2 Recently, there has been emerging interest in the use of defecation posture-modifying devices (DPMDs) to improve constipation symptoms, presumably by replicating the physiologic benefits of squatting on stool evacuation, such as straightening of the anorectal angle and relaxing the pelvic floor. However, the ability of DPMDs to normalize anorectal function in adult patients with CC has not been studied.

Dyssynergic Defecation: A Comprehensive Review on Diagnosis and Management

About one-third of chronically constipated patients have an evacuation disorder, and dyssynergic defecation is a common cause of the evacuation disorder. In dyssynergic defecation, the coordination between abdominal and pelvic floor muscles during defecation is disrupted and patients cannot produce a normal bowel movement. The etiology of dyssynergic defecation is still unknown. Although a detailed history taking and a careful examination including digital rectal examination could be useful, other modalities such as anorectal manometry and balloon expulsion test are necessary for the diagnosis. Biofeedback therapy is one of the most effective and safe treatments. Here, we provide an overview of dyssynergic defecation as well as how to diagnose and manage this condition.

Development of a Simple, Point-of-Care Device to Test Anorectal Function in Patients with Constipation: Randomized Clinical Trial

Functional constipation (FC) is one of the most frequently encountered gastrointestinal conditions in practice.¹ Practice guidelines universally recommend that patients with typical constipation symptoms and no alarm features be treated empirically with dietary/lifestyle interventions and laxative therapy.^2,3 Unfortunately, by the time a patient reaches a gastroenterologist, these treatments frequently have already been tried. Anorectal function testing (anorectal manometry [ARM] and balloon expulsion test [BET]) is the next best step in management guidelines in this all-too-common scenario, because treatment can then be targeted toward pelvic floor dysfunction or colon transit abnormalities. Unfortunately, more than 95% of patients continue to take only over-the-counter laxatives and receive empirical dietary advice, whereas fewer than 2% undergo physiologic evaluation to ascertain the cause of their symptoms.⁴ Indeed, more than 90% of patients desire more effective treatment options. These observations call into question the wisdom of a management strategy that fails to recognize the intrinsic diversity of the constipation universe and reinforces the misguided "one size fits all" empirical treatment strategy.

A Randomized, Double-Blind, Controlled Trial of Percutaneous Tibial Nerve Stimulation With Pelvic Floor Exercises in the Treatment of Childhood Constipation

INTRODUCTION

The management of childhood constipation is challenging. Pelvic floor dysfunction (PFD) is one of the most common causes of childhood constipation. Percutaneous tibial nerve stimulation (PTNS) with pelvic floor exercises (PFE) has achieved a satisfactory outcome in the elderly individuals and women with PFD. The efficacy of PTNS with PFE in childhood constipation has not been established.

METHODS

A randomized, double-blind, controlled trial with 84 children who met the inclusion criteria was conducted. All participants were randomly assigned to PTNS with PFE or sham PTNS with PFE groups and received their individual intervention for 4 weeks with a 12-week follow-up evaluation. The spontaneous bowel movements (SBM) ≥3 per week were the main outcomes, and the risk ratio (RR) with 95% confidence interval (CI) were calculated. High-resolution anorectal manometry and surface electromyography were used for the assessment of pelvic floor function, and the adverse effects were assessed based on symptoms.

RESULTS

At the end of the follow-up period, 26 patients (61.9%) in the PTNS with PFE group and 15 patients (35.7%) in the sham group had ≥3 SBM per week compared with baseline (net difference 26.2%, 95% CI 5.6%-46.8%; RR 2.750, 95% CI 1.384-5.466; P < 0.05). PFD remission occurred in 49 children, 33 (78.6%) in the PTNS with PFE group and 16 (38.1%) in the sham group (RR 2.063, 95% CI 1.360-3.128, P < 0.05). No adverse effects occurred.

DISCUSSION

PTNS with PFE is a safe and effective method in the treatment of childhood constipation, particularly in children with PFD or dyssynergic defecation.

Anorectal manometry for the diagnosis of pelvic floor disorders in patients with hypermobility spectrum disorders and hypermobile Ehlers-Danlos syndrome

INTRODUCTION

Functional gastrointestinal disorders (FGID) including impaired rectal evacuation are common in patients with Hypermobility Spectrum Disorder (HSD) or Hypermobile Ehlers-Danlos Syndrome (hEDS). The effect of connective tissue pathologies on pelvic floor function in HSD/hEDS remains unclear. We aimed to compare clinical characteristics and anorectal pressure profile in patients with HSD/hEDS to those of age and sex matched controls.

METHODS

We conducted a retrospective review of all FGID patients who underwent high resolution anorectal manometry (HR-ARM) and balloon expulsion test (BET) for evaluation of impaired rectal evacuation. Patients with HSD/hEDS were age and sex matched to a randomly selected cohort of control patients without HSD/hEDS. An abnormal BET was defined as the inability to expel a rectal balloon within 2 minutes. Wilcoxon rank sum test and Fisher's exact test were used to make comparisons and logistic regression model for predictive factors for abnormal evacuation.

RESULTS

A total of 144 patients (72 with HSD/hEDS and 72 controls) were analyzed. HSD/hEDS patients were more likely to be Caucasian (p < 0.001) and nulliparous. Concurrent psychiatric disorders; depression, and anxiety (p < 0.05), and somatic syndromes; fibromyalgia, migraine and sleep disorders (p < 0.001) were more common in these patients. Rate of abnormal BET were comparable among the groups. HDS/hEDS patients had significantly less anal relaxation and higher residual anal pressures during simulated defecation, resulting in significantly more negative rectoanal pressure gradient. The remaining anorectal pressure profile and sensory levels were comparable between the groups. While diminished rectoanal pressure gradient was the determinant of abnormal balloon evacuation in non HSD/hEDS patients, increased anal resting tone and maximum volume tolerated were independent factors associated with an abnormal BET in HSD/hEDS patients. Review of defecography data from a subset of patients showed no significant differences in structural pathologies between HSD/hEDS and non HSD/hEDS patients.

CONCLUSIONS

These results suggest anorectal pressure profile is not compromised by connective tissue pathologies in HSD patients. Whether concurrent psychosomatic disorders or musculoskeletal involvement impact the pelvic floor function in these patients needs further investigation.

Review of the indications, methods, and clinical utility of anorectal manometry and the rectal balloon expulsion test

BACKGROUND

Anorectal manometry (ARM) comprehensively assesses anorectal sensorimotor functions.

PURPOSE

This review examines the indications, techniques, interpretation, strengths, and weaknesses of high-resolution ARM (HR-ARM), 3-dimensional high-resolution anorectal manometry (3D-HR-ARM), and portable ARM, and other assessments (i.e., rectal sensation and rectal balloon expulsion test) that are performed alongside manometry. It is based on a literature search of articles related to ARM in adults. HR-ARM and 3D-HR-ARM are useful for diagnosing defecatory disorders (DD), to identify anorectal sensorimotor dysfunction and guide management in patients with fecal incontinence (FI), constipation, megacolon, and megarectum; and to screen for anorectal structural (e.g., rectal intussusception) abnormalities. The rectal balloon expulsion test is a useful, low-cost, radiation-free, outpatient assessment tool for impaired evacuation that is performed and interpreted in conjunction with ARM. The anorectal function tests should be interpreted with reference to age- and sex-matched normal values, clinical features, and results of other tests. A larger database of technique-specific normal values and newer paradigms of analyzing anorectal pressure profiles will increase the precision and diagnostic utility of HR-ARM for identifying abnormal mechanisms of defecation and continence.

Clinical value of positive BET and pelvic floor dyssynergia in Chinese patients with functional defecation disorder

BACKGROUND

Functional defecation disorder (FDD) is a common subtype of functional constipation (FC). Balloon expulsion test (BET) and high resolution anorectal manometry (HR-ARM) are significant tools but their results are not always consistent.

AIMS

To investigate the characteristics of patients with positive BET and pelvic floor dyssynergia (PFD) and explore the value of both positive results in FDD diagnosis.

METHODS

We retrospectively diagnosed FC subtypes and enrolled FDD patients based on Rome-IV criteria. They underwent HR-ARM, BET and CTT tests. Then they were classified to two groups and further stratified by FDD subtypes. Validated questionnaires were applied to investigate patients' constipation, anxiety/depression and quality of life.

RESULTS

335 FDD patients were finally enrolled. They were classified into two groups according to whether BET and PFD were both positive (consistent or not). 84.48% showed consistent results. These patients had significantly higher anal residual pressure, lower anal relaxation rate, manometric defecation index (MDI) and a more negative rectoanal pressure gradient (RAPG) (Ps < .05). The specific distribution of FDD phenotypes in two groups showed significant difference (p = .021). Males suffered a more negative RAPG (p < .001) and age was correlated with anal relaxation rate (p < .001). A subset (177 individuals) was investigated with validated questionnaires. Scores for Defecation Symptoms, Physical Discomfort and GAD-7 score were significantly high in Consistent Group (Ps < .05). GAD-7 score was associated with Defecation Symptoms (p < .001) while anal residual pressure, GAD-7 and Defecation Symptoms score were linked to Physical Discomfort (Ps < .05). The diagnostic specificity and PPV for FDD rose significantly with positive BET and PFD.

CONCLUSION

FDD patients with positive BET and PFD suffered from severe defecation symptoms, anxiety and impaired QOL. Positive BET and PFD could be an ideal tool for screening FDD.

Rectal Evacuation Disorders are Associated With Poor Bowel Preparation in Patients With Chronic Constipation: Results From Two Centers

INTRODUCTION

We evaluated factors that can predict the adequacy of bowel preparation in patients with chronic constipation undergoing colonoscopy.

MATERIALS AND METHODS

We identified patients with chronic constipation who underwent anorectal manometry and at least 1 colonoscopy at 2 tertiary referral centers from 2003 to 2019. We also identified a subgroup of patients who underwent colonic transit testing through radiopaque marker testing. We determined demographic, medical, and constipation-related factors associated with poor bowel preparation and their effect on standardized quality metrics using univariate and multivariate analyses.

RESULTS

We identified 274 patients with chronic constipation who underwent anorectal manometry testing. Both outlet dysfunction (prolonged balloon expulsion) and slow-transit constipation were associated with suboptimal bowel preparation. Outlet dysfunction was also associated with decreased cecal intubation rates, adenoma detection rates, and sessile serrated polyp detection rates. In multivariable analyses controlling for demographics and known factors associated with poor bowel preparation, outlet dysfunction was associated with an almost 3-fold odds of suboptimal bowel preparation [odds ratio (OR): 2.9; 95% confidence interval (CI): 1.6-5.1] and a 3-fold reduction in cecal intubation rates (OR: 0.3; 95% CI: 0.1-0.8). Among those with radiopaque marker colonic transit testing available, slow-transit constipation was associated with a >2-fold odds of suboptimal bowel preparation (OR: 2.2; 95% CI: 1.1-4.4).

CONCLUSIONS

Among a cohort of patients with chronic constipation undergoing colonoscopy, outlet dysfunction was associated with suboptimal bowel preparation and other quality metrics. Constipated patients with a rectal evacuation disorder may represent a subgroup of patients that could benefit from individualized strategies for better bowel preparation.

Baseline Predictors of Discontinuation of Prescription Drug Therapy for IBS-C: Cohort Analysis at an Integrated Healthcare System

BACKGROUND

Effective prescription drug treatment of constipation-predominant irritable bowel syndrome (IBS-C) requires patients to remain on daily therapy, yet predictive factors to optimize treatment selection are unknown.

AIMS

We assessed whether common comorbidities including chronic overlapping pain conditions (COPCs), mood disorders, or concurrent medications influence the risk of discontinuing IBS-C prescription drug therapy.

METHODS

We included all IBS-C patients who initiated treatment with the secretagogues linaclotide or lubiprostone across the Michigan Medicine healthcare system between 2012 and 2016. A Cox proportional hazards model was constructed to model time-to-treatment discontinuation as a valid, quantifiable measure of IBS medication persistence using hazards ratios (HR) with 95% confidence intervals (CI).

RESULTS

Our cohort included 225 patients on linaclotide and 492 on lubiprostone (mean age 48.3 years, 86.9% women, 46.6% with at least one COPC, 60.3% with at least one mood disorder) with an average follow-up of 2.1 years. Patients with at least one COPC (HR = 0.566; 95%CI = 0.371-0.863) and also women (HR = 0.535; 95%CI = 0.307-0.934) had a lower risk of discontinuing linaclotide, while COPCs predicted a trend toward increased discontinuation of lubiprostone (HR = 1.254; 95%CI = 0.997-1.576). Age, comorbid mood disorders, and baseline use of narcotics or benzodiazepines did not significantly mediate the risk of treatment discontinuation; our findings remained stable in univariate and multivariable analyses.

CONCLUSIONS

COPCs and sex appear to influence the likelihood of discontinuation of two commonly prescribed secretagogues, while mood disorders, narcotics, and benzodiazepines may not. Routine assessment for comorbid COPCs prior to initiating therapy may optimize IBS-C treatment selection and outcomes in practice.

Anorectal manometry to diagnose dyssynergic defecation: Systematic review and meta-analysis of diagnostic test accuracy

BACKGROUND

Chronic constipation is a common condition, and dyssynergic defecation underlies up to 40% of cases. Anorectal manometry is recommended to assess for dyssynergic defecation among chronically constipated patients but remains poorly standardized. We aimed to evaluate the diagnostic accuracy of anorectal manometry and determine optimal testing parameters.

METHODS

We performed a systematic review with meta-analysis of diagnostic test accuracy including cohort studies of chronically constipated patients and case-control studies of patients with dyssynergic defecation or healthy controls. Meta-analysis was performed to determine summary sensitivity, specificity, and area under the curve (AUC) with 95% confidence intervals (CI).

KEY RESULTS

A total of 15 studies comprising 2140 patients were included. Including all studies (estimating optimal diagnostic accuracy), the AUC was 0.78 [95% CI 0.72-0.82], summary sensitivity was 79% [61%-90%], and summary specificity was 64% [44%-79%] to diagnose dyssynergic defecation. In cohort studies only (estimating real-world diagnostic accuracy), the AUC was 0.72 [0.66-0.77], summary sensitivity was 86% [64%-95%], and summary specificity was 49% [30%-68%]. Employing three consecutive simulated defecation attempts improved sensitivity to 94%. A fourth simulated defecation maneuver with air insufflation may improve accuracy. Measuring anorectal pressures to identify complex dyssynergic patterns did not improve real-world diagnostic accuracy estimates over anal pressure measurement alone. Choice of manometry system did not impact diagnostic accuracy.

CONCLUSIONS & INFERENCES

Following the current iteration of the London consensus protocol (three simulated defecation attempts measuring anal relaxation), the role of anorectal manometry in evaluating dyssynergic defecation appears limited. Future iterations of this protocol may improve diagnostic accuracy.

Digital Rectal Examination Is a Valuable Bedside Tool for Detecting Dyssynergic Defecation: A Diagnostic Study and a Meta-Analysis

BACKGROUND

Accurate dyssynergic defecation (DD) diagnosis depends on anorectal physiological tests that are not widely available.

AIM

The purpose of this study is to evaluate the diagnostic yield of digital rectal examination (DRE) compared with anorectal physiological tests in diagnosing DD in patients with constipation.

METHODS

A total of 218 chronic constipation patients who fulfilled the Rome IV diagnostic criteria for functional constipation (FC) and underwent a standardized DRE and high-resolution anorectal manometry (HRAM) test were enrolled in this study. The diagnostic accuracy of DRE compared with HRAM was evaluated, and the agreement between DRE and HRAM was calculated. Furthermore, a comprehensive literature search on PubMed, Web of Science, Cochrane Library, and Embase database was conducted to further elucidate the pooled diagnostic accuracy of DRE in DD patients.

RESULTS

A total of 101 patients (46.33%) had a DD pattern using HRAM, while 117 patients (53.67%) were diagnosed without DD. The sensitivity of DRE in diagnosing dyssynergia was 71.3%, and the specificity was 76.1%. There was a moderate agreement between DRE and HRAM for diagnosing DD (κ-coefficient = 0.474, P < 0.001). Meanwhile, six studies (including our study) comprising 964 constipated patients were included in our meta-analysis. The outcomes demonstrated that the AUC was 0.85 (95% CI 0.82-0.88) with 77% summary sensitivity (95% CI 65-86) and 80% summary specificity (95% CI 71-86) to diagnose DD.

CONCLUSIONS

DRE could be a valuable tool for screening DD. Our study revealed acceptable sensitivity and specificity of DRE in detecting dyssynergia compared with the physiological tests. Meanwhile, our study highlights that DRE remains an important tool in clinical practice.

Rectal Distension Increased the Rectoanal Gradient in Patients with Normal Rectal Sensory Function

BACKGROUND

Frequent observation of abnormal manometric patterns consistent with dyssynergia in healthy volunteers has warranted the need for reassessment of the current methods to enhance the diagnostic value of anorectal manometry in functional defecatory disorders. Whether rectal distention at simulated evacuation will affect anorectal pressure profile and increase rectoanal gradient is not known.

METHODS

One hundred and eight consecutive patients with chronic constipation, 93 females, median age 53 years (interquartile range: 40-65), were studied. Simulated evacuation was performed firstly with empty balloon and subsequently after balloon distention to 50 and 100 ml. Anorectal pressures were compared. We also performed subgroup analysis in relation to outcome of balloon expulsion test (BET). In addition, we studied the effect of rectal distension on the rectoanal pressure gradient with respect to rectal sensory function.

RESULTS

Rectal balloon distension at simulated evacuation improved rectoanal gradient and decreased the rate of dyssynergia during high-resolution anorectal manometry. In subgroup analysis, the increase in rectoanal gradient and correction of dyssynergia with rectal distension was limited to the patients who had normal BET and normal rectal sensory function. Rate of anal relaxation, residual anal pressures, and rectoanal gradient were significantly different between patients with and without normal BET at 50 ml of rectal distension. Rectoanal gradient recorded only after rectal distension, along with BMI and maximum tolerable volumes, could predict BET results independently in patients with chronic constipation.

CONCLUSIONS

Rectal distension during simulated evacuation will affect the anorectal pressure profile. Increase in rectoanal gradient and correction of dyssynergia was only significant in patients with normal rectal sensory function and normal BET.

Prevalence and Clinical Characteristics of Dyssynergic Defecation and Slow Transit Constipation in Patients with Chronic Constipation

Patients with chronic constipation who do not respond to initial treatments often need further evaluation for dyssynergic defecation (DD) and slow transit constipation (STC). The aims of this study are to characterize the prevalence of DD and STC in patients referred to a motility center with chronic constipation and correlate diagnoses of DD and STC to patient demographics, medical history, and symptoms. High-resolution ARM (HR-ARM), balloon expulsion testing (BET) and whole gut transit scintigraphy (WGTS) of consecutive patients with chronic constipation were reviewed. Patients completed questionnaires describing their medical history and symptoms at the time of testing. A total of 230 patients completed HR-ARM, BET, and WGTS. Fifty (22%) patients had DD, and 127 (55%) patients had STC. Thirty patients (13%) had both DD and STC. There were no symptoms that were suggestive of STC vs. DD; however, patients with STC and DD reported more severe constipation than patients with normal transit and anorectal function. Patients with chronic constipation often need evaluation for both DD and STC to better understand their pathophysiology of symptoms and help direct treatment.

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.

Pretest and Post-test Probabilities of Diagnoses of Rectal Evacuation Disorders Based on Symptoms, Rectal Exam, and Basic Tests: a Systematic Review

BACKGROUND & AIMS

There is controversy over the utility of symptoms, examination, and tests for diagnosis of rectal evacuation disorders (REDs) or slow-transit constipation (STC). We aimed to ascertain the pooled prevalence, sensitivity, specificity, and likelihood ratios for clinical parameters to determine pretest and post-test probabilities of diagnoses of RED and STC without RED.

METHODS

We searched the MEDLINE and PUBMED databases since 1999 for studies that used binary data to calculate sensitivity, specificity, and likelihood ratios to determine the diagnostic utility of history, symptoms, and tests for RED and STC. RED and STC were defined based on confirmation by at least 1 objective anorectal test or colonic transit test. Controls had normal test results based on the specific protocol in each study.

RESULTS

We reviewed 100 articles; 63 studies of RED and 61 studies of STC met the inclusion criteria. Among 3364 patients with chronic constipation, objective tests demonstrated RED alone, 27.2%; normal transit constipation alone, 37.2%; STC alone, 19.0%; and RED with STC, 16.6%. To diagnose RED, discriminant features were urinary symptoms (specificity, 100%; likelihood ratio, above 10; 58 patients), less than 2 findings of dyssynergia in a digital rectal exam (sensitivity, 83.2%; negative likelihood ratio, 0.2; 462 patients) and rectoanal pressure gradient below -40 mm Hg with high anal pressure during straining (specificity, 100%; likelihood ratio, above 10; 101 patients). The features most strongly associated with STC alone were call to stool (specificity, 91.5%; likelihood ratio, 10.5; 75 patients) and absence of abdominal distension, fullness, or bloating (sensitivity, 92.9%; negative likelihood ratio, 0.1; 93 patients).

CONCLUSIONS

In a systematic review, we found specific symptoms, lack of dyssynergia in a digital rectal exam, and findings on anorectal manometry to be highly informative and critical in evaluation of RED and STC.

Anorectal physiology in health: A randomized trial to determine the optimum catheter for the balloon expulsion test

BACKGROUND

Anorectal manometry (ARM) and balloon expulsion test (BET) are pivotal in investigation of anorectal disorders. There is controversy, however, about normal values and optimum methodology for performing these tests. Our aims were to compare BET using three different balloons and to establish normal values for ARM and BET in health.

METHODS

Forty-four female healthy subjects (mean age 56 ± 12 years) underwent ARM, followed by BET which was performed in a private toilet using three different catheters (party balloon, Foley catheter and a commercially available catheter) in a single-blinded randomized order. Outcome measures were time to balloon expulsion and comprehensive measures of anal sphincter function, the push maneuver and rectal sensation.

KEY RESULTS

The Foley catheter took longer to expel compared to both party and commercial balloons (both pairwise P < 0.001) with a wider distribution of results (P < 0.001). Ten of 40 healthy subjects could not expel the Foley catheter within 120 seconds. On ARM, older age was associated with lower resting anal sphincter pressure (ρ = -0.3, P = 0.05) and lower anal squeeze pressure (ρ = -0.3, P = 0.05). Having at least one vaginal delivery (compared to none) was associated with lower anal squeeze pressures (P = 0.03) and a smaller difference between cough and squeeze pressures (P = 0.03).

CONCLUSIONS & INFERENCES

A commercial balloon exhibited superior results in vivo compared to the Foley catheter without the concerns of latex allergy and quality control present with the use of a party balloon. Normal values for high-resolution water-perfused manometry have been established and an effect seen for age and parity.