Epidemiology, pathophysiology, and classification of fecal incontinence: state of the science summary for the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) workshop

Cell therapy to improve regeneration of skeletal muscle injuries

Diseases that jeopardize the musculoskeletal system and cause chronic impairment are prevalent throughout the Western world. In Germany alone, ~1.8 million patients suffer from these diseases annually, and medical expenses have been reported to reach 34.2bn Euros. Although musculoskeletal disorders are seldom fatal, they compromise quality of life and diminish functional capacity. For example, musculoskeletal disorders incur an annual loss of over 0.8 million workforce years to the German economy. Among these diseases, traumatic skeletal muscle injuries are especially problematic because they can occur owing to a variety of causes and are very challenging to treat. In contrast to chronic muscle diseases such as dystrophy, sarcopenia, or cachexia, traumatic muscle injuries inflict damage to localized muscle groups. Although minor muscle trauma heals without severe consequences, no reliable clinical strategy exists to prevent excessive fibrosis or fatty degeneration, both of which occur after severe traumatic injury and contribute to muscle degeneration and dysfunction. Of the many proposed strategies, cell-based approaches have shown the most promising results in numerous pre-clinical studies and have demonstrated success in the handful of clinical trials performed so far. A number of myogenic and non-myogenic cell types benefit muscle healing, either by directly participating in new tissue formation or by stimulating the endogenous processes of muscle repair. These cell types operate via distinct modes of action, and they demonstrate varying levels of feasibility for muscle regeneration depending, to an extent, on the muscle injury model used. While in some models the injury naturally resolves over time, other models have been developed to recapitulate the peculiarities of real-life injuries and therefore mimic the structural and functional impairment observed in humans. Existing limitations of cell therapy approaches include issues related to autologous harvesting, expansion and sorting protocols, optimal dosage, and viability after transplantation. Several clinical trials have been performed to treat skeletal muscle injuries using myogenic progenitor cells or multipotent stromal cells, with promising outcomes. Recent improvements in our understanding of cell behaviour and the mechanistic basis for their modes of action have led to a new paradigm in cell therapies where physical, chemical, and signalling cues presented through biomaterials can instruct cells and enhance their regenerative capacity. Altogether, these studies and experiences provide a positive outlook on future opportunities towards innovative cell-based solutions for treating traumatic muscle injuries-a so far unmet clinical need.

Three-dimensional high-resolution anorectal manometry can predict response to biofeedback therapy in defecation disorders

PURPOSE

Biofeedback therapy (BT) is a simple and effective technique for managing outlet constipation and fecal incontinence. Several clinical factors are known to predict BT response, but a 50% failure rate persists. Better selection of BT responsive patients is required. We aimed to determine whether the defecation disorder type per high-resolution manometry (HRM) was predictive of BT response.

METHODS

We analyzed clinical, manometric, and ultrasound endoscopic data from patients who underwent BT in our department between January 2015 and January 2016. Patients were classified into four groups per the following defecation disorder classification criteria: rectal pressure > 40 mmHg and anal paradoxical contraction (type I); rectal pressure < 40 mmHg and anal paradoxical contraction (type II); rectal pressure > 40 mmHg and incomplete anal relaxation (type III); and rectal pressure < 40 mmHg and incomplete anal relaxation (type IV). An experienced single operator conducted ten weekly 20-min sessions. Efficacy was evaluated with the visual analog scale.

RESULTS

Of 92 patients, 47 (50.5%) responded to BT. Type IV and type II defecation disorders were predictive of success (p = 0.03) (OR = 5.03 [1.02; 24.92]) and failure (p = 0.05) (OR = 0.41 [0.17; 0.99]), respectively. The KESS score severity before BT (p = 0.03) (OR = 0.9 [0.81; 0.99]) was also predictive of failure.

CONCLUSION

The manometry types identified according to the defecation disorder classification criteria were predictive of BT response. Our data confirm the role of three-dimensional HRM in the therapeutic management of anorectal functional disorders.

Downregulation of thromboxane A2 and angiotensin II type 1 receptors associated with aging-related decrease in internal anal sphincter tone

Aging-associated decrease in internal anal sphincter (IAS) tone (AADI) is a major contributor in the rectoanal incontinence (RI). To determine the pathogenesis of AADI, we investigated the effect of aging on GPCR activation and related downstream signaling. We particularly investigated two GPCRs that characterize IAS smooth muscle cells (SMCs): thromboxane A2 and angiotensin II type 1. Two groups of Fischer 344 rats (6-month-old [young group] and 26-month-old [old group]) were employed to determine the GPCR function by isometric contraction, the expressions of GPCRs, and their downstream regulatory signaling proteins (regulator of G-protein signaling 2, RGS2; GPCR Kinase 5, GRK5; and β-arrestin, Arrb2) using RT-PCR, qPCR, and western blot analyses. We used reversible biotinylation to monitor the GPCR trafficking using SMCs. Aging selectively attenuated thromboxane A2 and Ang II-induced IAS contraction. RT-PCR, qPCR, and WB data revealed a significant decrease in the expressions of the GPCRs and increase in the expression of RGS2, GRK5, and Arrb2. The increased GPCR internalization and decreased recycling under aging were validated by reversible biotinylation. We conclude that downregulation of GPCR, accompanied by upregulation of regulatory proteins, plays an important role in receptor desensitization and may be important underlying mechanisms of RI in certain aging patients.

Cortico-anorectal, Spino-anorectal, and Cortico-spinal Nerve Conduction and Locus of Neuronal Injury in Patients With Fecal Incontinence

BACKGROUND & AIMS

The neuropathophysiology of fecal incontinence (FI) is incompletely understood. We examined the efferent brain-anorectal and spino-anorectal motor-evoked potentials (MEP) to characterize the locus of neuronal injury in patients with FI.

METHODS

We performed bilateral transcranial, translumbar, and transsacral magnetic stimulations in 27 patients with FI (19 female) and 31 healthy individuals (controls, 20 female) from 2015 through 2017. MEPs were recorded simultaneously from the rectum and anus using 4 ring electrodes. The difference in MEP latencies between the transcranial (TMS) and translumbar transsacral magnetic stimulations was calculated as cortico-spinal conduction time. MEP data were compared between patients with FI and controls. Patients filled out questionnaires that assessed the severity and effects of FI.

RESULTS

The MEP latencies with TMS were significantly longer in patients with FI than controls at most sites, and on both sides (P < .05). Almost all translumbar and transsacral MEP latencies were significantly prolonged in patients with FI vs controls (P < .01). The cortico-spinal conduction time were similar, on both sides, between patients with FI and controls. Ninety-three percent of patients had 1 or more abnormal translumbar and transsacral latencies, but neuropathy was patchy and variable, and not associated with sex or anal sphincter function or defects.

CONCLUSIONS

Patients with FI have significant neuropathy that affects the cortico-anorectal and spino-anorectal efferent pathways. The primary loci are the lumbo-rectal, lumbo-anal, sacro-rectal, and sacro-anal nerves; the cortico-spinal segment appears intact. Peripheral spino-anal and spino-rectal neuropathy might therefore contribute to the pathogenesis of FI.

A Practical Guide to Biofeedback Therapy for Pelvic Floor Disorders

PURPOSE OF REVIEW

Biofeedback therapy (BFT) is effective for managing pelvic floor disorders (i.e., defecatory disorders and fecal incontinence). However, even in controlled clinical trials, only approximately 60% of patients with defecatory disorders experienced long-term improvement. The review serves to update practitioners on recent advances and to identify practical obstacles to providing biofeedback therapy.

RECENT FINDINGS

The efficacy and safety of biofeedback therapy have been evaluated in defecatory disorders, fecal incontinence, and levator ani syndrome. Recent studies looked at outcomes in specific patient sub-populations and predictors of a response to biofeedback therapy. Biofeedback therapy is effective for managing defecatory disorders, fecal incontinence, and levator ani syndrome. Patients who have a lower bowel satisfaction score and use digital maneuvers fare better. Biofeedback therapy is recommended for patients with fecal incontinence who do not respond to conservative management. A subset of patients with levator ani syndrome who have dyssynergic defecation are more likely to respond to biofeedback therapy.

Three-dimensional high-resolution anorectal manometry in functional anorectal disorders: results from a large observational cohort study

BACKGROUND

The aim of the study was to describe the results of 3D high-resolution anorectal manometry (3DHRAM) in a large cohort of patients with functional anorectal disorders.

METHODS

In this single-center retrospective study, all consecutive patients referred for investigation of fecal incontinence (FI) or dyssynergic defecation (DD) underwent 3DHRAM. The parameters analyzed were usual manometric data, repartition of dyssynergic patterns, and the prevalence of a new "muscular subtype classification" underlying dyssynergia, anal sphincter defects, and pelvic floor disorders.

RESULTS

Final analyses were performed in 1477 patients with a mean age 54 ± 16 years; 825 patients suffered from DD, and 652 patients suffered from FI. Among these patients, 86% met the diagnostic criteria for dyssynergia. Type II dyssynergia was the most frequently observed (56%) in women and men suffering from FI and in women with DD. Type I was the most frequently observed in men with DD (49%). Regarding the muscle type subgroups, combined puborectalis muscle involvement with an external anal sphincter profile was the most frequently observed. The global prevalence of rectal intussusception and excessive perineal descent were 12% and 21%, respectively. Type III dyssynergia was more frequently associated with pelvic floor disorders than were other types of dyssynergia (p < 0.001).

CONCLUSION

This large cohort study provides reference values for 3DHRAM in patients with functional anorectal disorders. Further studies are necessary to assess the prevalence of pelvic floor disorders in healthy volunteers and to develop new scores and classifications including all of these new parameters.

ACOG Practice Bulletin No. 210 Summary: Fecal Incontinence

Fecal incontinence, or the involuntary leakage of solid or loose stool, is estimated to affect 7-15% of community-dwelling women (). It is associated with reduced quality of life, negative psychologic effects, and social stigma (), yet many women do not report their symptoms or seek treatment. Less than 3% of women who do self-report fecal incontinence will have this diagnosis recorded in their medical record (). Obstetrician-gynecologists are in a unique position to identify women with fecal incontinence because pregnancy, childbirth, obstetric anal sphincter injuries (OASIS), and pelvic floor dysfunction are important risk factors that contribute to fecal incontinence in women. The purpose of this Practice Bulletin is to provide evidence-based guidelines on the screening, evaluation, and management of fecal incontinence to help obstetrician-gynecologists diagnose the condition and provide conservative treatment or referral for further work up and surgical management when appropriate. For discussion on fecal incontinence associated with OASIS, see Practice Bulletin No. 198, Prevention and Management of Obstetric Lacerations at Vaginal Delivery ().

Effects of delivery mode and age on motor unit properties of the external anal sphincter in women

INTRODUCTION AND HYPOTHESIS

This study aimed to assess the individual and interactive effects of delivery mode and age on the function of the external anal sphincter (EAS) by analyzing the motor unit properties with intramuscular electromyography (EMG). Results are expected to improve the understanding of delivery-related occult obstetric EAS injuries and its development over the aging process and further support early clinical detection and intervention.

METHODS

A total of 49 postpartum women were recruited into four test groups according to their age and delivery mode: young vaginal delivery (Y-VD), elderly vaginal delivery (E-VD), young cesarean section (Y-CS), and elderly cesarean section (E-CS) groups. Anorectal ultrasonography, manometry, and intramuscular EMG were employed for comprehensive evaluation of EAS function.

RESULTS

No significant difference in anorectal ultrasonography and most manometry measurements was associated with delivery age or mode. Intramuscular EMG, however, revealed a statistically significant difference in the characteristics of motor unit potentials (MUPs), including duration, turns, phases, and multiphase wave ratio between four subject groups. No significant interaction effect between age and delivery mode was found.

CONCLUSIONS

Delivery mode and age have a significant effect on the neuromuscular function of the EAS, suggesting a potential protectiveness of cesarean section against impairment to the EAS. Our results do not provide significant evidence regarding the interaction effect of delivery mode and age; further investigations are needed to confirm this conclusion.

Prevalence of incontinence among cognitively impaired older residents in long-term care facilities in East Asia: A cross-sectional study

AIM

The current study was an international cross-sectional study comparing the prevalence of incontinence among cognitively impaired older residents in long-term care facilities in East Asia, including Japan, Korea, China, Taiwan and Thailand between 2015 and 2016.

METHODS

Participants were cognitively impaired older residents in long-term care facilities. Demographic data were collected. The Clinical Dementia Rating scale was used to assess dementia severity, and the Barthel Index was used as a surrogate measure of incontinence and toilet use dependence. The prevalence of urinary incontinence and fecal incontinence were examined. Multiple logistic regression analysis was used to predict incontinence and toilet use dependence.

RESULTS

We analyzed data from 662 participants (age 82.6 ± 9.9 years, 57.6% women). The prevalence of urinary incontinence ranged from 10.1% in Taiwan to 71.0% in Korea. The prevalence of fecal incontinence varied from 4.0% in Taiwan to 57.0% in Korea. A higher Clinical Dementia Rating score was a significant predictor of urinary and fecal incontinence and toilet use dependence (P < 0.0001).

CONCLUSIONS

The current survey showed a high prevalence of incontinence in long-term care residents in East Asia, and identified challenges for future studies. Development of clinical guidelines for incontinence care in cognitively impaired older persons is urgently required. Geriatr Gerontol Int 2019; 19: 444-450.

Regenerative medicine as a therapeutic option for fecal incontinence: a systematic review of preclinical and clinical studies

BACKGROUND

Fecal incontinence is the uncontrollable loss of stool and has a prevalence of around 7-15%. This condition has serious implications for patients' quality of life. Current treatment options show unsatisfactory results. A novel treatment option is therefore needed.

OBJECTIVE

This systematic review aims to perform a quality assessment and to give a critical overview of the current research available on regenerative medicine as a treatment for fecal incontinence.

STUDY DESIGN

A systematic search strategy was applied in PubMed, Cochrane Library, EMBASE, MEDLINE, Web of Science, and Cinahl from inception until March of 2018. Studies were found relevant when the animals or patients in the studied group had objectively determined or induced fecal incontinence, and the intervention must have used any kind of cells, stem cells, or biocompatible material, with or without the use of trophic factors. Studies were screened on title and consecutively on abstract for relevance by 2 independent investigators. The risk of bias of preclinical studies was assessed using the SYstematic Review Centre for Laboratory animal Experimentation risk of bias tool for animal studies, and for clinical studies the Cochrane risk of bias tool for randomized trials was used.

RESULTS

In all, 34 preclinical studies and 5 clinical studies were included. Animal species, type of anal sphincter injury, intervention, and outcome parameters were heterogenous. Therefore, a meta-analysis could not be performed. The overall risk of bias of the included studies was high.

CONCLUSION

The efficacy of regenerative medicine to treat fecal incontinence could not be determined due to the high risk of bias and heterogenicity of the available preclinical and clinical studies. The findings of this systematic review may result in improved study design of future studies, which could help the translation of regenerative medicine to the clinic as an alternative to current treatments for fecal incontinence.

Double incontinence: associated factors and impact on the quality of life of women attended at a health referral service

Abstract Objective: To evaluate the prevalence, associated factors, and impact on quality of life of double incontinence in a group of women with urinary incontinence. Method: A cross-sectional study was performed, including female patients with urinary or double incontinence (urinary and fecal incontinence) treated at a tertiary hospital from the public healthcare system. Information about sociodemographic and clinical characteristics was collected, and quality of life was assessed using validated questionnaires. The Mann-Whitney, Chi-square, and Fisher tests were used to evaluate the association between the variables and the types of dysfunction (urinary or double incontinence) and a worse general health perception. Results: Of 227 incontinent women included in the study, 120 (52,9%) were older individuals. The prevalence of double incontinence was 14.1% (32 patients). Double incontinence was associated with a higher number of comorbidities (p-value=0.04), polypharmacy (p-value=0.04), and rectocele (p-valor=0.02). Higher BMI (p-value=0.02) and number of comorbidities (p-value=0.05), but not double incontinence (p-value=0.36), were associated with low general health perception scores. Conclusion: the prevalence of double incontinence was different from other studies conducted in similar scenarios. The group of women included in the study presented low general health perception scores, but this was not associated with the presence of double incontinence. A higher number of comorbidities was associated with both double incontinence and a lower general health perception.

Gatekeeper Improves Voluntary Contractility in Patients With Fecal Incontinence

Background. Gatekeeper (GK) has shown to be safe and effective in patients with fecal incontinence (FI). We aimed to understand its mechanism of action by comparing pre- and post-implant change in the external anal sphincter (EAS) contractility. Methods. Study of EAS contractility was conducted in 16 FI females (median age = 69 years) before and after implant of 6 GK prostheses. Muscle tension (Tm), expressed in millinewtons per centimeter squared, mN(cm²)⁻¹, was calculated using the equation Tm = P(r_i)(tm)⁻¹, where P is the average maximum squeeze pressure and r_i and tm the inner radius and thickness of the EAS, respectively. The effect of a predefined set of covariates on Tm was tested by restricted maximum likelihood models. Results. Compared with baseline, despite unchanged tm (2.7 [2.5-2.8] vs 2.5 [2.2-2.8] mm; P = .31 mm), a significant increase in P (median = 45.8 [26.5-75.8] vs 60.4 [43.1-88.1] mm Hg; P = .017), and r_i (12.4 [11.5-13.4] vs 18.7 [17.3-19.6] mm; P < .001) resulted in an increase in Tm (233.2 [123.8-303.2] vs 490.8 [286.9-562.4] mN(cm²)⁻¹; P < .001) at 12 months after GK implant. Twelve-month follow-up improvements were also observed on Cleveland Clinic FI score (8-point median decrease; P = .0001), St Marks FI score (10-point median decrease; P < .0001), and American Medical Systems score (39-point median decrease; P < .0001). Restricted maximum likelihood models showed that years of onset of FI was negatively associated with change in Tm (P = .048). Conclusions. GK-related EAS compression positively influences muscle contractility by increasing r_i, with consequent increase in Tm (length-tension relationship). Further studies are needed to confirm the long-term effectiveness of GK.

Physical Activity, BMI, and Risk of Fecal Incontinence in the Nurses' Health Study

BACKGROUND

Higher body mass index (BMI) and low physical activity have been associated with increased prevalence of fecal incontinence (FI) in cross-sectional studies, but prospective studies examining the role of these factors are lacking. We sought to determine whether BMI and/or physical activity are associated with risk of FI among older women.

METHODS

We prospectively examined the association between BMI and physical activity and risk of FI in the Nurses' Health Study among 51,708 women who were free of FI in 2008. We defined FI as at ≥1 liquid or solid FI episode/month during the past year reported in 2010 or 2012. We used Cox proportional hazards models to calculate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for FI according to physical activity and BMI, adjusting for potential confounding factors.

RESULTS

During more than 175,000 person-years of follow-up, we documented 5954 cases of incident FI. Compared with women in the lowest activity category (<3 metabolic equivalent of task (MET)-hrs/week), multivariable-adjusted HRs for FI were 0.86 (95% CI 0.80-0.93) for women doing 3-8 MET-hrs/week, 0.78 (95% CI 0.72-0.84) for 9-17 MET-hrs/week, 0.76 (95% CI 0.69-0.83) for 18-26 MET-hrs/week, and 0.75 (95% CI 0.70-0.81) for 27 + MET-hrs/week (P_trend = <0.0001). There was no association between BMI and risk of FI.

CONCLUSIONS

Higher levels of physical activity were associated with a modest reduction (25%) in risk of incident FI among older women. These results support a potential role of ongoing physical activity in the neuromuscular health of the anorectal continence mechanism with aging.

TRANSLATIONAL IMPACT

These results support a potential role of ongoing physical activity in the neuromuscular health of the anorectal continence mechanism with aging.

Assessment of brain activity during voluntary anal sphincter contraction: Comparative study in women with and without fecal incontinence

BACKGROUND

Voluntary anal sphincter function is driven by an extended network of brain structures, most of which are still unknown. Disturbances in this function may cause fecal incontinence. The aim of this study was to characterize the cerebral areas involved in voluntary contraction of the anorectal sphincter in healthy women and in a group of patients with fecal incontinence by using a standardized functional magnetic resonance imaging (fMRI) protocol.

METHODS

This comparative study included 12 healthy women (mean age 53.17 ± 4.93 years) and 12 women with fecal incontinence (56.25 ± 6.94 years). An MRI-compatible anal manometer was used to register voluntary external anal sphincter contraction. During brain fMRI imaging, participants were cued to perform 10-s series of self-paced anal sphincter contractions at an approximate rate of 1 Hz. Brain structures linked to anal sphincter contractions were mapped and the findings were compared between the 2 study groups.

KEY RESULTS

There were no differences in the evoked brain activity between the 2 groups. In healthy women, group fMRI analysis revealed significant activations in medial primary motor cortices, supplementary motor area, bilateral putamen, and cerebellum, as well as in the supramarginal gyrus and visual areas. In patients with fecal incontinence, the activation pattern involved similar regions without significant differences with healthy women.

CONCLUSIONS & INFERENCES

This brain fMRI-anorectal protocol was able to map the brain regions linked to voluntary anal sphincter function in healthy and women with fecal incontinence.

Increased Long-term Dietary Fiber Intake Is Associated With a Decreased Risk of Fecal Incontinence in Older Women

BACKGROUND & AIMS

Fiber supplements are frequently used as treatment for fecal incontinence (FI), but little is known about the role of dietary fiber in the prevention of FI.

METHODS

We performed a prospective study to examine the association between long-term dietary fiber intake and risk of FI in 58,330 older women (mean age, 73 years) in the Nurses' Health Study who were free of FI in 2008. Energy-adjusted long-term dietary fiber intake was determined using food frequency questionnaires starting in 1984 and updated through 2006. We defined incident FI as at least 1 liquid or solid FI episode per month during the past year during 4 years of follow-up using self-administered biennial questionnaires. We used Cox proportional hazards models to calculate multivariable-adjusted hazard ratios and 95% CIs for FI according to fiber intake, adjusting for potential confounding factors.

RESULTS

During 193,655 person-years of follow-up, we documented 7,056 incident cases of FI. Compared with women in the lowest quintile of fiber intake (13.5 g/day), women in the highest quintile (25 g/day) had an 18% decrease in risk of FI (multivariable hazard ratio, 0.82; 95% CI, 0.76-0.89). This decrease appeared to be greatest for risk of liquid stool FI, which was 31% lower in women with the highest intake of fiber compared with women with the lowest intake (multivariable hazard ratio, 0.69; 95% CI, 0.62-0.75). Risk of FI was not significantly associated with fiber source.

CONCLUSIONS

In an analysis of data from almost 60,000 older women in the Nurses' Health Study, we found higher long-term intake of dietary fiber was associated with decreased risk of FI. Further studies are needed to determine the mechanisms that mediate this association.

Risk Factors for Fecal Urgency Among Individuals With and Without Diarrhea, Based on Data From the National Health and Nutrition Examination Survey

BACKGROUND & AIMS

Fecal urgency is a common symptom among patients with gastrointestinal disorders, but can also occur in healthy individuals with normal bowel habits. There have been few studies of fecal urgency in the general population. We performed a cross-sectional analysis of data from the National Health and Nutrition Examination Survey (NHANES) to analyze the prevalence of and risk factors for this symptom.

METHODS

We analyzed data from 4676 persons who completed the Bowel Health Questionnaire from the NHANES, from 2009 through 2010. The NHANES sampled a nationally representative group of adults in the United States and provides information on demographics, medical comorbidities, and dietary habits of survey participants. The Bowel Health Questionnaire provided additional information about bowel symptoms such as urgency, incontinence, constipation, and diarrhea. We identified individuals with fecal urgency and calculated differences in fecal urgency among subgroups using chi-squared analysis. We used logistic regression to identify factors associated with urgency.

RESULTS

In our study population, the prevalence of fecal urgency was 3.3%; 29.5% of individuals with fecal urgency had diarrhea. The prevalence of fecal urgency was significantly higher in individuals who had diarrhea (14.8%) than in individuals without diarrhea (3.1%). Older age, female sex, poverty, urinary urge incontinence, diarrhea, and increased stool frequency were all associated with fecal urgency on multivariable analysis. Decreased fiber intake and increased carbohydrate intake were associated with urgency among individuals with diarrhea.

CONCLUSIONS

In an analysis of data from 4676 individuals who completed a Bowel Health Questionnaire from the NHANES, we found a significantly higher proportion of individuals with diarrhea to have fecal urgency. However, most individuals with fecal urgency do not have diarrhea. Factors associated with fecal urgency vary among individuals with and without diarrhea.

Innervation asymmetry of the external anal sphincter in aging characterized from high-density intra-rectal surface EMG recordings

AIMS

The innervation zone asymmetry of the external anal sphincter (EAS) has been investigated as a risk factor for the development of fecal incontinence (FI). This study aims to utilize an intra-rectal high-density surface electromyogram (HD-sEMG) recording and advanced HD-sEMG decomposition technique to characterize the effects of aging on the asymmetry of EAS functional innervation.

METHODS

HD-sEMG signals were recorded intra-rectally from six healthy young and seven healthy elderly women during voluntary contractions of the EAS. EMG signals were decomposed into constituent motor unit action potentials (MUAPs) and the innervation zone of each decomposed motor unit was identified. Asymmetry index (AI) was defined and calculated for all subjects. The maximum squeezing pressures of the EAS were also measured for all subjects as a comparison.

RESULTS

The HD-sEMG decomposition and AI calculation were successfully performed from EMG data acquired from all the subjects. The AI values were 28.7 ± 17.0% for the young group and 55.6 ± 18.8% for the elderly group. The AI and EAS contraction strength were found to be negatively correlated (P < 0.05). A two-tailed student's t-test demonstrated a significant increase in AI with age by comparison between two groups (P < 0.05).

CONCLUSIONS

Our work demonstrates, for the first time, that EAS functional innervation tends to become increasingly asymmetrical with advancing age, and this increase is associated with a compromised anorectal function. Results suggest that the intra-rectal HD-sEMG will serve as an advanced tool for assessing and monitoring the anorectal neuromuscular function minimally invasively under different pathophysiological conditions.

Subtypes and symptoms of fecal incontinence in the Dutch population: a cross-sectional study

PURPOSE

To study the distribution of subtypes and symptoms of fecal incontinence in the general Dutch population.

METHODS

We performed a cross-sectional study in a representative sample of the general Dutch population. All respondents (N = 1259) completed the Groningen Defecation and Fecal Continence questionnaire. We assigned the respondents to a so-called healthy subgroup (n = 1008) and a comorbidity subgroup (n = 251). The latter subgroup comprised the respondents who reportedly suffered from chronic diseases and who had undergone surgery known to influence fecal continence. We defined fecal incontinence according to the Rome IV criteria.

RESULTS

The combination of urge fecal incontinence and soiling was the most frequent form of fecal incontinence in the total study group, the "healthy" subgroup, and the comorbidity subgroup (49.0, 47.3, and 51.5%). Passive fecal incontinence was the least frequent form of fecal incontinence in all three groups (4.0, 5.4, and 2.2%). The prevalence and severity of fecal incontinence was significantly higher in the comorbidity subgroup than in the "healthy" subgroup. Only in the comorbidity subgroup did the fecally incontinent respondents feel urge sensation significantly less often before defecating than their fecally continent counterparts (16.5 versus 48.8%, P < 0.001).

CONCLUSION

Urge fecal incontinence combined with soiling is commonest in the general Dutch population. Chronic diseases and bowel and pelvic surgery both increase and aggravate fecal incontinence.

Structure-function relationship of the human external anal sphincter

INTRODUCTION AND HYPOTHESIS

Obstetrical external anal sphincter (EAS) injury and subsequent dysfunction are leading risk factors for female fecal incontinence (FI). Limited knowledge of the EAS structure-function relationship hinders treatment optimization. We directly measured functionally relevant intrinsic parameters of human EAS and tested whether vaginal delivery alters the EAS structure-function relationship.

METHODS

Major predictors of in vivo EAS function were compared between specimens procured from vaginally nulliparous (VN, n = 5) and vaginally parous (VP, n = 7) cadaveric donors: operational sarcomere length (Ls), which dictates force-length relationship; physiological cross-sectional area (PCSA), which determines isometric force-generating capacity; fiber length (Lfn), responsible for muscle excursion and contractile velocity; and muscle stiffness. Data were analyzed using unpaired and paired t tests, α < 0.05. Results are presented as mean ± SEM.

RESULTS

The VN and VP (median parity 3) groups were similar in age and BMI. No gross anatomical defects were identified. EAS Ls (2.36 ± 0.05 μm) was shorter than the optimal Lso (2.7 μm), at which contractile force is maximal, P = 0.0001. Stiffness was lower at Ls than Lso (5.4 ± 14 kPa/μm vs 35.3 ± 12 kPa/μm, P < 0.0001). This structural design allows active and passive tension to increase with EAS stretching. EAS relatively long Lfn (106 ± 24.8 mm) permits rapid contraction without decreased force, whereas intermediate PCSA (1.3 ± 0.3 cm2) is conducive to maintaining resting tone. All parameters were similar between groups.

CONCLUSIONS

This first direct examination of human EAS underscores how EAS intrinsic design matches its intended function. Knowledge of the EAS structure-function relationship is important for understanding the pathogenesis of FI and the optimization of treatments for EAS dysfunction.

Gastrointestinal and urinary complaints in adults with hereditary spastic paraparesis

BACKGROUND

Hereditary spastic paraparesis (HSP) is a group of rare genetic disorders affecting the central nervous system. Pure HSP is limited to lower limb spasticity and urinary voiding dysfunction. Complex HSP involves additional neurological features. Beyond the described core symptoms, knowledge about the burden of disease for adults with HSP is limited, particularly regarding gastrointestinal functions, fecal incontinence, and urinary symptoms.

METHODS

We conducted a cross-sectional self-report survey with 108 adult HSP patients (M_age = 57.7 years, SD = 11.5, range 30 to 81; 54.2% females) recruited from a national HSP user group association and a national (non-clinical) advisory unit for rare disorders. HSP data was compared to data from a Norwegian population study, HUNT-3 (N = 46,293).

RESULTS

The HSP group reported more gastrointestinal and urinary complaints compared to controls. Gastrointestinal complaints included at least "much" complaints with constipation (14.6%) and alternating constipation/diarrhea (8.0%), and at least daily uncontrollable flatulence (47.6%), fecal incontinence (11.6%), and inability to hold back stools (38.5%). Urinary complaints included frequent urination (27.4% > 8 times daily), sudden urge (51.9%) and urinary incontinence (30.5% at least daily/nightly).

CONCLUSION

This survey of adults with HSP recruited from non-clinical settings showed constipation, alternate constipation and diarrhea, fecal incontinence, and voiding dysfunction represent considerable problems for many persons with HSP. Health care providers should screen and manage often unrecognized gastrointestinal and fecal incontinence complaints among HSP patients.

High-Resolution Anorectal Manometry - New Insights in the Diagnostic Assessment of Functional Anorectal Disorders

Functional anorectal disorders such as faecal incontinence (FI), functional anorectal pain, and functional defecation disorders (FDD) are highly prevalent and represent a high socioeconomic burden. Several tests of anorectal function exist in this setting; however, high-resolution anorectal manometry (HR-ARM) is a new tool that depicts pressure all along the anal canal and can assess rectoanal coordination. HR-ARM is used in the diagnosis of FI and especially FDD although data in health is still sparse, and pressure phenomena seen during simulated defecation, such as dyssynergia, are highly prevalent in health.

The "rectosigmoid brake": Review of an emerging neuromodulation target for colorectal functional disorders

The regulation of gastrointestinal motility encompasses several overlapping mechanisms including highly regulated and coordinated neurohormonal circuits. Various feedback mechanisms or "brakes" have been proposed. While duodenal, jejunal, and ileal brakes are well described, a putative distal colonic brake is less well defined. Despite the high prevalence of colonic motility disorders, there is little knowledge of colonic motility owing to difficulties with organ access and technical difficulties in recording detailed motor patterns along its entire length. The motility of the colon is not under voluntary control. A wide range of motor patterns is seen, with long intervals of intestinal quiescence between them. In addition, the use of traditional manometric catheters to record contractile activity of the colon has been limited by the low number of widely spaced sensors, which has resulted in the misinterpretation of colonic motor patterns. The recent advent of high-resolution (HR) manometry is revolutionising the understanding of gastrointestinal motor patterns. It has now been observed that the most common motor patterns in the colon are repetitive two to six cycles per minute (cpm) propagating events in the distal colon. These motor patterns are prominent soon after a meal, originate most frequently in the rectosigmoid region, and travel in the retrograde direction. The distal prominence and the origin of these motor patterns raise the possibility of them serving as a braking mechanism, or the "rectosigmoid brake," to limit rectal filling. This review aims to describe what is known about the "rectosigmoid brake," including its physiological and clinical significance and potential therapeutic applications.

Evaluation of the Fecal Incontinence Quality of Life Scale (FIQL) using item response theory reveals limitations and suggests revisions

PURPOSE

The Fecal Incontinence Quality of Life Scale (FIQL) is a commonly used patient-reported outcome measure for fecal incontinence, often used in clinical trials, yet has not been validated in English since its initial development. This study uses modern methods to thoroughly evaluate the psychometric characteristics of the FIQL and its potential for differential functioning by gender.

METHODS

This study analyzed prospectively collected patient-reported outcome data from a sample of patients prior to colorectal surgery. Patients were recruited from 14 general and colorectal surgeons in Vancouver Coastal Health hospitals in Vancouver, Canada. Confirmatory factor analysis was used to assess construct validity. Item response theory was used to evaluate test reliability, describe item-level characteristics, identify local item dependence, and test for differential functioning by gender.

RESULTS

236 patients were included for analysis, with mean age 58 and approximately half female. Factor analysis failed to identify the lifestyle, coping, depression, and embarrassment domains, suggesting lack of construct validity. Items demonstrated low difficulty, indicating that the test has the highest reliability among individuals who have low quality of life. Five items are suggested for removal or replacement. Differential test functioning was minimal.

CONCLUSIONS

This study has identified specific improvements that can be made to each domain of the Fecal Incontinence Quality of Life Scale and to the instrument overall. Formatting, scoring, and instructions may be simplified, and items with higher difficulty developed. The lifestyle domain can be used as is. The embarrassment domain should be significantly revised before use.

Relationship between symptoms and quality of life in fecal incontinence

BACKGROUND

Most measures of fecal incontinence (FI) severity assess the frequency of solid and liquid FI, but may incorporate other features. We compared two scales-the Fecal Incontinence Severity Score (FISS) and Fecal Incontinence Severity Index (FISI)-to determine which questionnaire and which individual questions predict FI Quality of Life (FIQOL).

METHODS

A national sample of American adults completed a health questionnaire, and 234 with monthly FI were selected. Participants completed assessments of FI severity, FIQOL, and somatization. Stepwise linear regression models evaluated whether FISS and FISI total scores, or individual items on the FISS and FISI predicted FIQOL after adjusting for gender, age, income, and somatization (Brief Symptom Inventory-18).

KEY RESULTS

Reliable responses were provided by 186. Age was 49 years, and 52% were women. The mean FISS score was 8.4 (95% confidence interval [CI] 8.0-8.9, 13 questions) and mean FISI was 29.9 (95% CI 27.4-32.4, 62 questions), indicating moderate FI severity. The mean FIQOL was 2.6 (95% CI 2.4-2.7, 5 questions). Lower income, greater somatization, and total FISS and FISI scores explained 69% of FIQOL; and total FISS and FISI scores were independent predictors. On the FISS, frequency, amount, and urgency to defecate were independently associated with FIQOL. After adding somatization, all but amount remained significant. For the FISI scale, solid and liquid FI and gas were significant predictors, but adjusting for somatization excluded solid FI.

CONCLUSIONS AND INFERENCES

Five variables independently explained FIQOL: overall frequency of FI, frequency of liquid and gas leakage, urgency, and somatization.

Irritable Bowel Syndrome and Quality of Life in Women With Fecal Incontinence

OBJECTIVES

The objectives of this work were to determine the prevalence of irritable bowel syndrome (IBS) and IBS subtypes in women presenting for fecal incontinence (FI) treatment and to assess the impact of IBS on FI symptoms and quality of life (QOL).

METHODS

In this multicenter prospective cohort study, women reported at least monthly solid, liquid, or mucus FI. Rome III clinical criteria defined IBS. Women also self-reported having an IBS diagnosis. Baseline questionnaires included the following: Modified Manchester Health Questionnaire, Fecal Incontinence Severity Index, Bristol Stool Scale, Pelvic Floor Distress Inventory, and the Pelvic Floor Impact Questionnaire.

RESULTS

Of the 133 women enrolled, 119 completed Rome III IBS questionnaires, and 111 reported on whether they had a previous diagnosis of IBS. The prevalence of IBS was 31% (95% confidence interval [CI], 22.9%-40.2%) according to the Rome III IBS criteria. The most common subtypes were IBS-mixed (41%) and IBS-diarrhea (35%). Twenty-four (22%) of 111 patients had a previous diagnosis of IBS. Among women who met Rome III IBS criteria, 23 (66%) of 35 women had never had a diagnosis of IBS. Women with FI and IBS reported significantly worse QOL compared to women without IBS despite similar FI severity and stool consistency.

CONCLUSIONS

Irritable bowel syndrome negatively affects QOL and affects one third of women with FI presenting for care in tertiary centers. Our findings suggest that assessment of IBS symptoms and diagnosis may be important for women presenting for FI treatment.

Modern Theories of Pelvic Floor Support : A Topical Review of Modern Studies on Structural and Functional Pelvic Floor Support from Medical Imaging, Computational Modeling, and Electromyographic Perspectives

PURPOSE OF REVIEW

Weakened pelvic floor support is believed to be the main cause of various pelvic floor disorders. Modern theories of pelvic floor support stress on the structural and functional integrity of multiple structures and their interplay to maintain normal pelvic floor functions. Connective tissues provide passive pelvic floor support while pelvic floor muscles provide active support through voluntary contraction. Advanced modern medical technologies allow us to comprehensively and thoroughly evaluate the interaction of supporting structures and assess both active and passive support functions. The pathophysiology of various pelvic floor disorders associated with pelvic floor weakness is now under scrutiny from the combination of (1) morphological, (2) dynamic (through computational modeling), and (3) neurophysiological perspectives. This topical review aims to update newly emerged studies assessing pelvic floor support function among these three categories.

RECENT FINDINGS

A literature search was performed with emphasis on (1) medical imaging studies that assess pelvic floor muscle architecture, (2) subject-specific computational modeling studies that address new topics such as modeling muscle contractions, and (3) pelvic floor neurophysiology studies that report novel devices or findings such as high-density surface electromyography techniques. We found that recent computational modeling studies are featured with more realistic soft tissue constitutive models (e.g., active muscle contraction) as well as an increasing interest in simulating surgical interventions (e.g., artificial sphincter). Diffusion tensor imaging provides a useful non-invasive tool to characterize pelvic floor muscles at the microstructural level, which can be potentially used to improve the accuracy of the simulation of muscle contraction. Studies using high-density surface electromyography anal and vaginal probes on large patient cohorts have been recently reported. Influences of vaginal delivery on the distribution of innervation zones of pelvic floor muscles are clarified, providing useful guidance for a better protection of women during delivery. We are now in a period of transition to advanced diagnostic and predictive pelvic floor medicine. Our findings highlight the application of diffusion tensor imaging, computational models with consideration of active pelvic floor muscle contraction, high-density surface electromyography, and their potential integration, as tools to push the boundary of our knowledge in pelvic floor support and better shape current clinical practice.

Fecal incontinence knowledge, attitudes, and help-seeking behaviors among community-dwelling adults in Korea

OBJECTIVES

Fecal incontinence (FI) is a common debilitating disorder that tends to be underreported. Although low health literacy likely contributes to the underreporting, studies on FI knowledge among the general population remain scarce. We investigated how FI knowledge is associated with attitudes and help-seeking behaviors.

METHODS

We conducted a cross-sectional survey among community-dwelling adults undergoing national health screening in Korea. A structured, self-administered questionnaire was used to assess FI knowledge, attitudes, and help-seeking behaviors. Odds ratios (ORs; 95% confidence intervals, CIs) were estimated using logistic regression with adjustment for covariables.

RESULTS

Of the 601 participants completing the survey, only 29.8% were aware of the term FI, and their knowledge levels were insufficient. As for FI-related attitudes, 24.6% considered FI to be very rare, and 22.3% considered it to be moderately or less distressing. Individuals who knew the term FI tended to consider FI more common (OR: 2.45; 95%CI: 1.49-4.02) and distressing (OR: 1.68; 95%CI: 1.07-2.63) than those without knowledge. Assuming future FI occurrence, those considering FI to be distressing were less willing to ignore or self-manage the condition (OR: 0.25; 95%CI: 0.11-0.58). Among patients with FI (n = 83), only 30.1% had sought help and 8.4% had consulted doctors. Knowing the term FI was significantly associated with overall help-seeking behavior (OR: 9.23; 95%CI: 2.09-40.77).

CONCLUSIONS

FI knowledge levels and help-seeking rates were low among community-dwelling adults. FI knowledge was significantly associated with attitudes and help-seeking behaviors. Future public education programs are warranted to improve FI knowledge, attitudes, and help-seeking behaviors.

In vivo magnetofection: a novel approach for targeted topical delivery of nucleic acids for rectoanal motility disorders

In these studies, we developed a novel approach of in vivo magnetofection for localized delivery of nucleic acids such as micro-RNA-139-5p (miR-139-5p; which is known to target Rho kinase2) to the circular smooth muscle layer of the internal anal sphincter (IAS). The IAS tone is known to play a major role in the rectoanal continence via activation of RhoA-associated kinase (RhoA/ROCK2). These studies established an optimized protocol for efficient gene delivery using an assembly of equal volumes of in vivo PolyMag and miR139-5p or anti-miR-139-5p (100 nM each) injected in the circular smooth muscle layer in the pinpointed areas of the rat perianal region and then incubated for 20 min under magnetic field. Magnetofection efficiency was confirmed and analyzed by confocal microscopy of FITC-tagged siRNA. Using physiological and biochemical approaches, we investigated the effects of miR-139-5p and anti-miR-139-5p on basal intraluminal IAS pressure (IASP), fecal pellet count, IAS tone, agonist-induced contraction, contraction-relaxation kinetics, and RhoA/ROCK2 signaling. Present studies demonstrate that magnetofection-mediated miR-139-5p delivery significantly decreased RhoA/ROCK2, p-MYPT1, and p-MLC₂₀ signaling, leading to decreases in the basal IASP and IAS tone and in rates of contraction and relaxation associated with increase in fecal pellet output. Interestingly, anti-miR-139-5p transfection had opposite effects on these parameters. Collectively, these data demonstrate that magnetofection is a promising novel method of in vivo gene delivery and of nucleotides to the internal anal sphincter for the site-directed and targeted therapy for rectoanal motility disorders. NEW & NOTEWORTHY These studies for the first time demonstrate the success of topical in vivo magnetofection (MF) of nucleic acids using perianal injections. To demonstrate its effectiveness, we used FITC-tagged siRNA via immunofluorescence microcopy and functional and biochemical evidence using miR-139-5p (which is known to target ROCK2). In conclusion, MF allows safe, convenient, efficient, and targeted delivery of oligonucleotides such as siRNAs and microRNAs. These studies have direct therapeutic implications in rectoanal motility disorders especially associated with IAS.

Microstructural white matter brain abnormalities in patients with idiopathic fecal incontinence

BACKGROUND

Abnormal central nervous system processing of visceral sensation may be a part of the pathogenesis behind idiopathic fecal incontinence (IFI). Our aim was to characterize brain differences in patients with IFI and healthy controls by means of structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI).

METHODS

In 21 female patients with IFI and 15 female healthy controls, whole-brain structural differences in gray matter volume (GMV), cortical thickness, and white matter tracts fractional anisotropy (FA) were quantified. For this purpose, we used voxel-based morphometry, surface based morphometry and tract-based spatial statistic, respectively. Furthermore, associations between structural brain characteristics and latencies of rectal sensory evoked electroencephalography potentials were determined.

KEY RESULTS

Compared to healthy controls, IFI patients had significantly reduced FA values, reflecting reduced white matter tract integrity, in the left hemisphere superior longitudinal fasciculus (SLF), posterior thalamic radiation, and middle frontal gyrus (MFG), all P<.05. No differences were observed in GMV or in cortical thickness. The reduced FA values in the SLF and MFG were correlated with prolonged latencies of cortical potentials evoked by rectal stimuli (all P<.05).

CONCLUSIONS & INFERENCES

This explorative study suggests that IFI patients have no macrostructural brain changes, but exhibit microstructural changes in white matter tracts relevant for sensory processing. The clinical relevance of this finding is supported by its correlations with prolonged latencies of cortical potentials evoked by rectal stimulation. This supports the theories of central nervous system changes as part of the pathogenesis in IFI patients.

Trends in Surgeon-Level Utilization of Sacral Nerve Stimulator Implantation for Fecal Incontinence in New York State

BACKGROUND

There is a paucity of real-world data regarding surgeon utilization of sacral nerve stimulation for fecal incontinence compared with anal sphincteroplasty.

OBJECTIVE

This study aims to examine trends in sacral nerve stimulation use compared with sphincteroplasty for fecal incontinence and surgeon-level variation in progression to implantation of the pulse generator.

DESIGN

This is a population-based study.

PATIENTS

Patients with fecal incontinence between 2011 and 2014 in New York who underwent stage 1 of the sacral nerve stimulation procedure were selected. For the comparison with sphincteroplasty, patients with fecal incontinence who underwent anal sphincteroplasty between 2008 and 2014 were included.

MAIN OUTCOME MEASURES

The main outcomes after sacral nerve stimulation generator placement were unplanned 30-day admission, emergency department visit within 30 days, revision or explant of leads or generator, and 30-day mortality.

RESULTS

Six hundred twenty-one patients with fecal incontinence underwent a stage 1 procedure with 79.7% progressing to stage 2. There has been an increase in the number of sacral nerve stimulation cases per year as well as the number of surgeons performing the procedure. The rate of progression to stage 2 among patients treated by colorectal surgeons was 80.2% compared with 77.0% among those treated by noncolorectal surgeons. Among those who completed stage 2, there were 3 (0.5%) unplanned 30-day admissions, 24 (4.4%) emergency department visits within 30 days, and 0 mortalities within 30 days. Thirty-two (6.5%) patients had their leads or pulse generator revised or explanted. There was a significant decrease in annual sphincteroplasty cases and the number of providers performing the procedure starting in 2011.

LIMITATIONS

We lacked data regarding patient and physician decision making and the severity of disease.

CONCLUSIONS

Sacral nerve stimulation for fecal incontinence is increasing in popularity with an increasing number of surgeons utilizing sacral nerve stimulation for fecal incontinence rather than sphincteroplasty. See Video Abstract at http://links.lww.com/DCR/A450.

Surgical Interventions and the Use of Device-Aided Therapy for the Treatment of Fecal Incontinence and Defecatory Disorders

The purpose of this clinical practice update expert review is to describe the key principles in the use of surgical interventions and device-aided therapy for managing fecal incontinence (FI) and defecatory disorders. The best practices outlined in this review are based on relevant publications, including systematic reviews and expert opinion (when applicable). Best Practice Advice 1: A stepwise approach should be followed for management of FI. Conservative therapies (diet, fluids, techniques to improve evacuation, a bowel training program, management of diarrhea and constipation with diet and medications if necessary) will benefit approximately 25% of patients and should be tried first. Best Practice Advice 2: Pelvic floor retraining with biofeedback therapy is recommended for patients with FI who do not respond to the conservative measures indicated above. Best Practice Advice 3: Perianal bulking agents such as intra-anal injection of dextranomer may be considered when conservative measures and biofeedback therapy fail. Best Practice Advice 4: Sacral nerve stimulation should be considered for patients with moderate or severe FI in whom symptoms have not responded after a 3-month or longer trial of conservative measures and biofeedback therapy and who do not have contraindications to these procedures. Best Practice Advice 5: Until further evidence is available, percutaneous tibial nerve stimulation should not be used for managing FI in clinical practice. Best Practice Advice 6: Barrier devices should be offered to patients who have failed conservative or surgical therapy, or in those who have failed conservative therapy who do not want or are not eligible for more invasive interventions. Best Practice Advice 7: Anal sphincter repair (sphincteroplasty) should be considered in postpartum women with FI and in patients with recent sphincter injuries. In patients who present later with symptoms of FI unresponsive to conservative and biofeedback therapy and evidence of sphincter damage, sphincteroplasty may be considered when perianal bulking injection and sacral nerve stimulation are not available or have proven unsuccessful. Best Practice Advice 8: The artificial anal sphincter, dynamic graciloplasty, may be considered for patients with medically refractory severe FI who have failed treatment or are not candidates for barrier devices, sacral nerve stimulation, perianal bulking injection, sphincteroplasty and a colostomy. Best Practice Advice 9: Major anatomic defects (eg, rectovaginal fistula, full-thickness rectal prolapse, fistula in ano, or cloaca-like deformity) should be rectified with surgery. Best Practice Advice 10: A colostomy should be considered in patients with severe FI who have failed conservative treatment and have failed or are not candidates for barrier devices, minimally invasive surgical interventions, and sphincteroplasty. Best Practice Advice 11: A magnetic anal sphincter device may be considered for patients with medically refractory severe FI who have failed or are not candidates for barrier devices, perianal bulking injection, sacral nerve stimulation, sphincteroplasty, or a colostomy. Data regarding efficacy are limited and 40% of patients had moderate or severe complications. Best Practice Advice 12: For defecatory disorders, biofeedback therapy is the treatment of choice. Best Practice Advice 13: Based on limited evidence, sacral nerve stimulation should not be used for managing defecatory disorders in clinical practice. Best Practice Advice 14: Anterograde colonic enemas are not effective in the long term for management of defecatory disorders. Best Practice Advice 15: The stapled transanal rectal resection and related procedures should not be routinely performed for correction of structural abnormalities in patients with defecatory disorders.

Age-related external anal sphincter muscle dysfunction and fibrosis: possible role of Wnt/β-catenin signaling pathways

Studies show an age-related increase in the prevalence of anal incontinence and sphincter muscle atrophy. The Wnt/β-catenin signaling pathway has been recently recognized as the major molecular pathway involved in age-related skeletal muscle atrophy and fibrosis. The goals of our study were to 1) evaluate the impact of normal aging on external anal sphincter (EAS) muscle length-tension (L-T) function and morphology and 2) specifically examine the role of Wnt signaling pathways in anal sphincter muscle fibrosis. New Zealand White female rabbits [6 young (6 mo of age) and 6 old (36 mo of age)] were anesthetized, and anal canal pressure was measured to determine the L-T function of EAS. Animals were killed at the end of the study, and the anal canal was harvested and processed for histochemical studies (Masson trichrome stain for muscle/connective tissue) as well as for molecular markers for fibrosis and atrophy [collagen I, β-catenin, transforming growth factor-β (TGF-β), atrogin-1, and muscle-specific RING finger protein-1 (MuRF-1)]. The L-T was significantly impaired in older animals compared with young animals. Anal canal sections stained with trichrome showed a significant decrease in the muscle content (52% in old compared with 70% in young) and an increase in the connective tissue/collagen content in the old animals. An increased protein and mRNA expression of all the fibrosis markers was seen in the older animals. Aging EAS muscle exhibits impairment of function and increase in connective tissue. Upregulation of atrophy and profibrogenic proteins with aging may be the reason for the age-related decrease in anal sphincter muscle thickness and function.NEW & NOTEWORTHY Our studies using a female rabbit model show age-related alterations in the structure and function of the external anal sphincter (EAS) muscle. We used endoluminal ultrasound to measure age-related changes in EAS muscle thickness. We employed Western blot and quantitative PCR to demonstrate age-related changes in the levels of important fibrogenic as well as atrophy markers. Our findings may have significant clinical implications, i.e., use of specific antagonists to prevent age-related EAS muscle dysfunction.

Prevalence of anal incontinence in a working population within a healthcare environment

OBJECTIVES

Anal incontinence is a devastating affliction with several considerations that make it difficult to define in terms of epidemiology with good precision. The aim of the present work is to study the prevalence of an important disorder such as anal incontinence in a healthy working population within a sanitary environment.

MATERIAL AND METHODS

A cluster of easy understanding and filling inquiry forms are distributed to 910 apparently healthy individuals at our hospital. This questionnaires include filiation data, passed medical history, presence or not of Incontinence and other symptoms such as urgency. The Cleveland Clinic Incontinence Score is also registered.

RESULTS

Anal incontinence is present in a 21.2% of subjects when considered in any of it forms (flatus, liquid or solid faeces). A Clevleand Clinic Incontinence Score higher than 6 was obtained in a 7.3% of the sample and higher than 10 in 1.2%. No gender predominance has been identified. A slightly higher severity is recognised with increasing age. Obstetric and anal surgical background are the only related factors identified in the studied sample.

CONCLUSIONS

Faecal incontinence is a high prevalent affliction, even among apparently healthy population. Considering the aetiologic factors that have been established, prevention during obstetric and anal surgical procedures is absolutely mandatory.

Association of urinary phenolic compounds, inflammatory bowel disease and chronic diarrheal symptoms: Evidence from the National Health and Nutrition Examination Survey

Endocrine disruptors such as phenolic compounds and parabens may be involved in chronic non-infective disease. While products incorporating these compounds are extensively utilized in consumer and personal products, little is known about their effect on bowel health. Inflammatory bowel disease (IBD) - consisting of the diseases ulcerative colitis and Crohn's disease - and irritable bowel syndrome are common chronic non-infectious diarrheal diseases. Despite limited knowledge on the etiology of IBD, these diseases have increased prevalence in industrialized countries and cause significant impairment to quality of life. In the present study we examine relationships between urinary environmental phenolic compounds, chronic diarrhea and inflammatory bowel disease. Data was obtained from the 2005-2010 US National Health and Nutrition Examination Survey (NHANES) including demographics, lifestyle factors, self-reported health conditions, inflammatory markers and urinary phenolic chemical concentrations. Only participants with complete environmental phenols & parabens component were included in our analysis. Chronic diarrheal symptoms were determined by using the 2009-2010 NHANES questionnaire which included questions pertaining to bowel health. We utilized chronic bowel leakage symptoms as a surrogate marker for chronic diarrhea. The presence of IBD was also analyzed from 2009 to 2010 NHANES data, as a sub-analysis for arthropathy directly querying the presence or absence of IBD. Among the subset of 5218 American adults aged 20-80 years in the NHANES study period who completed environmental phenols & parabens component, 25.5% reported chronic diarrheal symptoms. Abnormal markers of inflammation were present in 2200 (42.2%) of respondents. For IBD, 19 individuals with arthropathy confirmed a diagnosis of ulcerative colitis, and 1 person confirmed a Crohn's diagnosis. After adjustment for demographics, inflammatory and subsample weighing; lower paraben levels were associated with chronic bowel leakage (diarrheal) symptoms. Higher 4-tert-octylphenol levels was significantly associated with ulcerative colitis. Further study of underlying mechanisms should be considered.

3D High-definition anorectal manometry: Values obtained in asymptomatic volunteers, fecal incontinence and chronic constipation. Results of a prospective multicenter study (NOMAD)

BACKGROUND

3D-high definition anorectal manometry (3DARM) may aid the diagnosis of functional anorectal disorders, but data comparing asymptomatic and symptomatic subjects are scarce. We aimed to describe 3DARM values in asymptomatic volunteers and those with fecal incontinence (FI) or chronic constipation (CC), and identify which variables differentiate best these groups.

METHODS

Asymptomatic subjects were stratified by sex, age, and parity. Those with FI or CC were included according to anorectal symptom questionnaires. Endoanal ultrasound examination and 3DARM were performed the same day. Anal pressures were analyzed at rest, during voluntary squeeze, and during push maneuver, and compared between the 3 groups. Anal pressure defects were defined and compared to ultrasound defects.

KEY RESULTS

A total of 126 subjects (113 female, mean age 52 years, range 18-83) were included; 36 asymptomatic, 38 FI, 42 CC. Anal resting and squeeze pressures, and rectal sensitivity values were lower in FI women than in the other groups. Typical anal sphincter asymmetry during squeezing was less frequently observed in FI women. A dyssynergic pattern during push maneuver was found in 70% of asymptomatic subjects, and with a similar frequency in the 2 symptomatic groups. There was slight concordance between 3D-pressure defects and ultrasound defects.

CONCLUSIONS & INFERENCES

3D anal pressures in asymptomatic women were significantly lower than in men, and in FI compared to asymptomatic women. The classical dyssynergic pattern during push maneuver was found as frequently in asymptomatic and symptomatic patients. Further studies should try to identify 3DARM variables that could reliably identify dyssynergic defecation.

Pathophysiology of fecal incontinence in obese patients: A prospective case-matched study of 201 patients

BACKGROUND

Obesity is an emerging risk factor for fecal incontinence (FI). The aim of this study was to characterize pathophysiologic mechanisms of FI in obese patients compared with non-obese patients in a prospective case-matched study.

METHODS

The general characteristics and data of the anorectal manometry and endosonography of patients who were evaluated for FI at a single institution from 2005 to 2015 were prospectively assessed. Fecal incontinence was defined by a Cleveland Clinic Incontinence Score (CCIS) >4. Obesity was defined by a body mass index ≥30 kg/m² . Obese patients were case-matched with two age- and sex-matched non-obese patients.

KEY RESULTS

A total of 201 patients were included (67 obese matched with 134 non-obese). The CCIS, Knowles-Eccersley-Scott Symptom Constipation Score and quality of life score were comparable between obese and non-obese patients with FI. Factors significantly associated with obesity in FI patients were cholecystectomy (odds ratio [OR]=3.45 [1.19-10.32], P=.0230), irritable bowel syndrome - diarrhea (OR=2.94 [1.22-7.19], P=.0158), upper part of the anal canal resting pressure ≥22 mm Hg (OR=3.45 [1.45-8.76], P=.0045), maximum rectal tolerable volume ≥240 mL (OR=3.14 [1.34-7.54], P=.0082), and abdominal pressure ≥28 mm Hg (OR=2.75 [1.13-7.33], P=.0248) by multivariate analysis.

CONCLUSIONS & INFERENCES

Obese patients with FI had a comparable severity of FI to that of non-obese patients with FI. Regarding obesity in patients with FI, physicians should focus on stool consistency.

Robotic Placement of the FENIX Continence Restoration System in a Patient with Previous Radiation to the Pelvis: A Case Report

Fecal incontinence (FI) is a disabling problem affecting women. Conservative treatment includes dietary modification, antimotility agents, and pelvic floor physical therapy. If conservative medical management is unsuccessful, surgical intervention may be required. Surgical options include rectal sphincteroplasty, bulking agent injection, radiofrequency anal sphincter remodeling, and sacral nerve stimulation therapy. Recently, a new therapy for FI, the FENIX Continence Restoration System (Torax Medical, Inc., Shoreview, MN), has become available. The FENIX device is placed through a perineal incision; however, pelvic radiation and previous anal carcinoma are both contraindications. We report the case of a 62-year-old woman with FI after anal carcinoma. Treatment included surgery, chemotherapy, and pelvic radiation. Initially, she was treated with conservative therapy and sacral nerve stimulation, which were only partially effective. A physical examination showed perineal skin changes consistent with previous radiation, which increased the patient's risk of infection and a nonhealing wound. Therefore, a robotic approach was used to place the FENIX device and improve the patient's quality of life. Our case sets a precedent for expanding the treatment options of FI in patients with previous pelvic radiation and using a robotic approach for the placement of the FENIX device.

Age and Dyssynergia Subtypes Associated With Normal Sphincter Pressures in Women With Fecal Incontinence

OBJECTIVES

Fecal incontinence (FI) is frequently associated with low sphincter pressures, sensory abnormalities, and advanced age. Twenty-three percent of patients with FI and 22% of healthy patients demonstrate dyssynergic defecation (DD) on high-resolution anorectal manometry. Overflow incontinence occurs in some DD patients with normal resting and squeeze anal sphincter pressures. Our aim was to identify factors associated with normal sphincter pressures in women with FI.

METHODS

We reviewed medical records of 134 women with FI. Patients with normal resting and squeeze anal pressures were compared with those with abnormal pressures using Wilcoxon rank sum test and Fisher exact. Multivariable logistic regression was performed to identify factors associated with normal resting and squeeze anal pressures.

RESULTS

Among 134 women, abnormal resting and/or squeeze pressures were identified in 113 and normal pressures were identified in 21. Women with normal sphincter pressures were younger (mean age 52.7 ± 10.8 years vs 59.0 ± 14.0 years, P = 0.036), more often had abnormal defecation indices (100% vs 83.2%, P = 0.043) and higher rectal defecation pressures (30.8 ± 18.8 mm Hg vs 50.8 ± 22.6 mm Hg, P < 0.001). There was an overall association between DD subtype and normal and abnormal sphincter pressure groups (P = 0.021). Dyssynergia subtypes I or III (odds ratio, 7.2; 95% confidence interval, 1.8-28.8) and age younger than 67 years (odds ratio, 8.5; 95% confidence interval, 1.5-48.6) were associated with greater odds of having normal sphincter pressures.

CONCLUSIONS

Female FI patients with normal anal sphincter pressures are younger, have higher rectal defecation pressures, and more often have type I or type III DD.

Menopausal Hormone Therapy Is Associated With Increased Risk of Fecal Incontinence in Women After Menopause

BACKGROUND & AIMS

Low estrogen levels can contribute to development of fecal incontinence (FI) in women after menopause by altering neuromuscular continence mechanisms. However, studies have produced conflicting results on the association between menopausal hormone therapy (MHT) and risk of FI.

METHODS

We studied the association between MHT and risk of FI among 55,828 postmenopausal women (mean age, 73 years) who participated in the Nurses' Health Study, were enrolled since 2008, and with no report of FI. We defined incident FI as a report of at least 1 liquid or solid FI episode per month during 4 years of follow-up from self-administered, biennial questionnaires administered in 2010 and 2012. We used Cox proportional hazard models to calculate multivariate-adjusted hazard ratios and 95% confidence intervals (CIs) for FI risk in women receiving MHT, adjusting for potential confounding factors.

RESULTS

During more than 185,000 person-years of follow-up, there were 6834 cases of incident FI. Compared with women who never used MHT, the multivariate hazard ratio for FI was 1.26 (95% CI, 1.18-1.34) for past users of MHT and 1.32 (95% CI, 1.20-1.45) for current users. The risk of FI increased with longer duration of MHT use (P trend ≤ .0001) and decreased with time since discontinuation. There was an increased risk of FI among women receiving MHT that contained a combination of estrogen and progestin (hazard ratio, 1.37; 95% CI, 1.10-1.70) compared with estrogen monotherapy.

CONCLUSIONS

Current or past use of MHT was associated with a modestly increased risk of FI among postmenopausal women in the Nurses' Health Study. These results support a potential role for exogenous estrogens in the impairment of the fecal continence mechanism.

Role of differentially expressed microRNA-139-5p in the regulation of phenotypic internal anal sphincter smooth muscle tone

The present study focused on the role of microRNA-139-5p (miRNA-139-5p) in the regulation of basal tone in internal anal sphincter (IAS). Applying genome-wide miRNA microarrays on the phenotypically distinct smooth muscle cells (SMCs) within the rat anorectrum, we identified miRNA-139-5p as differentially expressed RNA repressor with highest expression in the purely phasic smooth muscle of anococcygeus (ASM) vs. the truly tonic smooth muscle of IAS. This pattern of miRNA-139-5p expression, previously shown to target ROCK2, was validated by target prediction using ingenuity pathway (IPA) and by qPCR analyses. Immunoblotting, immunocytochemistry (ICC), and functional assays using IAS tissues and cells subjected to overexpression/knockdown of miRNA-139-5p confirmed the inverse relationship between miRNA-139-5p and ROCK2 expressions/IAS tone. Overexpression of miRNA-139-5p caused a decrease, while knockdown by anti-miRNA-139-5p caused an increase in the IAS tone; these tissue contractile responses were confirmed by single-cell contraction using magnetic twisting cytometry (MTC). These findings suggest miRNA-139-5p is capable of significantly influencing the phenotypic tonicity in smooth muscle via ROCK2: a lack of tone in ASM may be associated with the suppression of ROCK2 by high expression of miRNA-139-5p, whereas basal IAS tone may be associated with the persistence of ROCK2 due to low expression of miRNA-139-5p.

Patient preferences for endpoints in fecal incontinence treatment studies

BACKGROUND

Randomized controlled trials of treatments for fecal incontinence (FI) are difficult to compare because case definitions and study endpoints vary. Our aims were to assess patient perspectives on the case definition for FI and how treatment success should be measured.

METHODS

In Phase 1, 28 FI patients participated in anonymous on-line focus groups, and in Phase 2, 186 people with FI, stratified by gender, race, and age completed an online survey.

KEY RESULTS

Focus group participants described frequency and urgency as the most important characteristics for defining FI. Most (80%) thought staining of underwear constitutes FI, but only 33% thought gas leakage was FI. When asked how the success of treatment should be defined, 77% said by a reduction in frequency or complete cure, but less than half thought a 50% reduction in frequency was enough. When asked how much reduction would be needed, responses averaged 80%. The Phase 2 survey confirmed that frequency, urgency, and intestinal discomfort are the most important characteristics for case definition, and that success should be defined by at least a 75% decrease in frequency. A 50% reduction was an acceptable endpoint for 58% overall but only 26% for those aged ≥65. "Adequate relief" was acceptable to 78%.

CONCLUSIONS AND INFERENCES

Inclusion criteria for trials should specify a minimum frequency of FI. Most patients would require a ≥75% reduction in FI frequency to call a treatment successful but young adults and those with more severe FI would accept a ≥50% reduction as meaningful.

Factors Associated with Fecal Incontinence in Women of Childbearing Age with Crohn's Disease

BACKGROUND

Fecal incontinence is common in women with Crohn's disease, but little is known about the impact of childbirth, perianal Crohn's disease, and past surgical history on fecal incontinence.

METHODS

Self-administered questionnaires were mailed to consecutive women referred to a tertiary gastroenterology centre with a focus on fecal incontinence and childbirth. These data were cross-referenced with a prospective database of the same patients' own Crohn's disease histories. Fecal incontinence was defined as a Cleveland Clinic Incontinence Score ≥5. Factors associated with fecal incontinence were analyzed.

RESULTS

A total of 173 patients were assessed, including 113 parous women. The prevalence of fecal incontinence was 37.5% (95% CI, 30.7-45.0). The disease duration, a history of anal surgery for fistula, the number of childbirths per woman and Crohn's activity were all independently associated with fecal incontinence in a multivariate analysis model. Specifically, among the group of parous women, fecal incontinence was associated with prior abdominal surgery, prior anal surgery, and Crohn's activity. The mode of delivery was not statistically associated with fecal incontinence.

CONCLUSIONS

Fecal incontinence is a significant complaint in at least one-third of women of childbearing age with Crohn's disease. Patients'disease and treatment histories seem to have a comparable effect to their childbirth history concerning the presence of fecal incontinence. Both physicians and surgeons who are involved in the management of Crohn's disease need to keep this in mind.

Gastrointestinal Complications of Obesity

Obesity usually is associated with morbidity related to diabetes mellitus and cardiovascular diseases. However, there are many gastrointestinal and hepatic diseases for which obesity is the direct cause (eg, nonalcoholic fatty liver disease) or is a significant risk factor, such as reflux esophagitis and gallstones. When obesity is a risk factor, it may interact with other mechanisms and result in earlier presentation or complicated diseases. There are increased odds ratios or relative risks of several gastrointestinal complications of obesity: gastroesophageal reflux disease, erosive esophagitis, Barrett's esophagus, esophageal adenocarcinoma, erosive gastritis, gastric cancer, diarrhea, colonic diverticular disease, polyps, cancer, liver disease including nonalcoholic fatty liver disease, cirrhosis, hepatocellular carcinoma, gallstones, acute pancreatitis, and pancreatic cancer. Gastroenterologists are uniquely poised to participate in the multidisciplinary management of obesity as physicians caring for people with obesity-related diseases, in addition to their expertise in nutrition and endoscopic interventions.

Wnt-β Catenin Signaling Pathway: A Major Player in the Injury Induced Fibrosis and Dysfunction of the External Anal Sphincter

Wnt-β catenin is an important signaling pathway in the genesis of fibrosis in many organ systems. Our goal was to examine the role of Wnt pathway in the external anal sphincter (EAS) injury-related fibrosis and muscle dysfunction. New Zealand White female rabbits were subjected to surgical EAS myotomy and administered local injections of either a Wnt antagonist (sFRP-2; daily for 7 days) or saline. Anal canal pressure and EAS length-tension (L-T) were measured for 15 weeks after which the animals were sacrificed. Anal canal was harvested and processed for histochemical studies (Masson trichrome stain), molecular markers of fibrosis (collagen and transforming growth factor-β) and immunostaining for β catenin. Surgical myotomy of the EAS resulted in significant impairment in anal canal pressure and EAS muscle L-T function. Following myotomy, the EAS muscle was replaced with fibrous tissue. Immunostaining revealed β catenin activation and molecular studies revealed 1.5–2 fold increase in the levels of markers of fibrosis. Local injection of sFRP-2 attenuated the β catenin activation and fibrosis. EAS muscle content and function was significantly improved following sFRP-2 treatment. Our studies suggest that upregulation of Wnt signaling is an important molecular mechanism of injury related EAS muscle fibrosis and sphincter dysfunction.

Fecal incontinence in irritable bowel syndrome: Prevalence and associated factors in Swedish and American patients

BACKGROUND

Fecal incontinence (FI) is a prevalent but poorly recognized problem in the general population with profound negative effects on daily life. The prevalence of FI in irritable bowel syndrome (IBS) and its association with clinical, demographic, and pathophysiological factors remain largely unknown.

METHODS

One US (n=304) and one Swedish (n=168) patient cohort fulfilling Rome III criteria for IBS completed Rome III diagnostic questions on FI and IBS symptoms, and questionnaires on IBS symptom severity, quality of life, anxiety and depression, and work productivity impairment. The patients also underwent assessments of colorectal sensitivity and motility.

KEY RESULTS

Fecal incontinence ≥ one day per month was reported by 19.7% (USA) and 13.7% (Sweden) of IBS patients. These proportions rose to 43.4% and 29.8% if patients with less frequent FI were included. Fecal incontinence prevalence was higher in older age groups, with a clear increase above age 40. Irritable bowel syndrome patients with FI reported greater overall IBS symptom severity, more frequent and loose stools, and greater urgency. Negative effects of FI on quality of life, psychological distress, and work productivity were demonstrated. No associations were found between colorectal physiology and FI.

CONCLUSIONS & INFERENCES

Fecal incontinence is common in IBS patients, and similar to previous general population reports, the major risk factors for FI in IBS are older age, rectal urgency, and loose, frequent stools. When IBS patients have comorbid FI, the impact on quality of life, psychological symptoms, and work impairment appears greater.