Fecal Incontinence: Pathogenesis, Diagnosis, and Updated Treatment Strategies

Effect of Single-Dose Imipramine on Anal Sphincter Tone in Healthy Women: A Randomized, Placebo-Controlled Study Using Anal Acoustic Reflectometry

INTRODUCTION AND HYPOTHESIS

Despite the high prevalence of fecal incontinence, existing treatment options may be inadequate. Drugs that enhance the tone of the anal sphincter complex could potentially be an effective pharmacological approach. This study investigated the effect of the tricyclic antidepressant imipramine on anal sphincter tone in healthy women, employing anal acoustic reflectometry as the evaluating method.

METHODS

In a double-blind, randomized, placebo-controlled crossover study, 16 healthy female volunteers were randomized to one of two treatment sequences. The participants attended two study visits separated by at least 7 days' washout. At each visit, they received a single dose of 50 mg imipramine or matching placebo, in alternating order. We assessed the anal opening pressure under the resting state and during voluntary squeezing of the pelvic floor. Measurements were performed pre-dose and 1 h after drug administration, corresponding to the estimated time of peak plasma concentration of imipramine.

RESULTS

All participants completed the study. In total, 44% of the participants reported at least one adverse effect, primarily anticholinergic. Compared with placebo, imipramine increased anal opening pressure by 15.2 cmH2O (95% confidence interval [CI] 2.0-28.2 cmH2O, p = 0.03) in the resting state and 15.1 (95% CI 4.2-26.0 cmH2O, p = 0.01) cmH2O during squeezing.

CONCLUSIONS

The findings indicate that imipramine increases anal sphincter tone in healthy women. However, further research is required to evaluate its clinical impact on individuals with fecal incontinence. This research also demonstrates the effectiveness of using anal acoustic reflectometry for assessing pharmacological effects on anal sphincter function.

Tissue engineering and regenerative medicine approaches in colorectal surgery

Tissue engineering and regenerative medicine (TERM) is an emerging field that has provided new therapeutic opportunities by delivering innovative solutions. The development of nontraditional therapies for previously unsolvable diseases and conditions has brought hope and excitement to countless individuals globally. Many regenerative medicine therapies have been developed and delivered to patients clinically. The technology platforms developed in regenerative medicine have been expanded to various medical areas; however, their applications in colorectal surgery remain limited. Applying TERM technologies to engineer biological tissue and organ substitutes may address the current therapeutic challenges and overcome some complications in colorectal surgery, such as inflammatory bowel diseases, short bowel syndrome, and diseases of motility and neuromuscular function. This review provides a comprehensive overview of TERM applications in colorectal surgery, highlighting the current state of the art, including preclinical and clinical studies, current challenges, and future perspectives. This article synthesizes the latest findings, providing a valuable resource for clinicians and researchers aiming to integrate TERM into colorectal surgical practice.

Effect of reboxetine and citalopram on anal opening pressure in healthy women: A randomized, double-blind, placebo-controlled crossover study

BACKGROUND

In placebo-controlled clinical trials, reboxetine, a selective noradrenaline reuptake inhibitor, increases urethral pressure and relieves stress urinary incontinence symptoms in women. Considering the close connection in neural regulation of the external urethral and anal sphincters, we hypothesized that reboxetine may also enhance anal sphincter pressure. Conversely, it is believed that selective serotonin reuptake inhibitors may contribute to fecal incontinence by reducing anal sphincter pressure. In this study, we investigated the effect of reboxetine and citalopram on anal opening pressure in healthy female volunteers.

METHODS

In a double-blind, three-way crossover trial, 24 female participants received single doses of 40 mg citalopram, 8 mg reboxetine, and matching placebos, with a minimum of 8-day washout between sessions. Using anal acoustic reflectometry, we measured anal opening pressure during both resting and squeezing conditions at the estimated time of peak plasma concentration for both study drugs.

KEY RESULTS

Compared with placebo, reboxetine increased anal opening pressure with 23.4 cmH2O (95% confidence interval [CI] 16.5-30.2, p < 0.001) during rest and with 22.5 cmH2O (95% CI 15.2-29.8, p < 0.001) during squeeze. Citalopram did not change anal opening pressure statistically significantly compared to placebo.

CONCLUSIONS & INFERENCES

An 8-mg dose of reboxetine increased anal opening pressure substantially in healthy women, suggesting potential benefits for fecal incontinence symptoms. In contrast, a 40-mg dose of citalopram showed a marginal and statistically insignificant effect on anal opening pressure, indicating that selective serotonin reuptake inhibitors do not contribute to fecal incontinence by reducing anal sphincter tone.

Bidirectional Relationships between Sarcopenia and Pelvic Floor Disorders

Sarcopenia and pelvic floor disorders (PFDs) are prevalent and often cooccurring conditions in the aging population. However, their bidirectional relationship and underlying mechanisms remain underexplored. This narrative review aims to elucidate this relationship by exploring potential causative interplays, shared pathophysiological mechanisms, and common risk factors. A comprehensive literature search was conducted to identify relevant studies focusing on epidemiological associations, interaction mechanisms, and implications for patient care. While epidemiological studies demonstrate associations between sarcopenia and PFDs, our findings reveal a cyclical relationship where sarcopenia may exacerbate PFDs through mechanisms such as decreased muscle strength and mobility. Conversely, the presence of PFDs often leads to reduced physical activity due to discomfort and mobility issues, which in turn exacerbate the muscle atrophy associated with sarcopenia. Additionally, shared risk factors such as physical inactivity, nutritional deficiencies, metabolic syndrome, and menopausal hormonal changes likely contribute to the onset and progression of both conditions. These interactions underscore the importance of concurrently integrated care approaches that address both conditions. Effective management requires comprehensive screening, the recognition of contributing factors, and tailored exercise regimens supported by a multidisciplinary approach. Future research should focus on longitudinal studies tracking disease progression and evaluating the efficacy of multidisciplinary care models in optimizing patient outcomes.

Association between low handgrip strength and incontinence among Chinese middle-aged and older people: A cross-sectional study

Objective

Incontinence seriously affects the lives of middle-aged and older people. Pelvic floor muscle assessment is very important for incontinence, and handgrip strength can be used as an auxiliary diagnostic tool. Our study aims to find new cutoff points of handgrip strength as early indicators of incontinence and analyze the association between low handgrip strength and incontinence among Chinese middle-aged and older people.

Methods

Participants were recruited from the 2015 China Health and Retirement Longevity Study. Receiver operating characteristic (ROC) curves were used to find the handgrip strength cutoff point. Logistic regression analysis was performed to explore other incontinence-related risk factors.

Results

The study included 10,229 middle-aged and older people. Compared with normal handgrip strength participants, medium strength participants had 1.510 [men, 95% confidence interval (CI) = 1.017-2.243] and 1.792 (women, 95% CI = 1.294-2.480) times greater risk of incontinence, and low strength participants had 2.420 (men, 95% CI = 1.787-3.277) and 1.516 (women, 95% CI = 1.130-2.032) times greater risk of incontinence. Trend test results showed that the risk of incontinence increased with decreasing handgrip strength in middle-aged and older people.

Conclusions

Our study suggests that handgrip strength < 31 kg in men and < 20.5 kg in women is significantly associated with higher risk of incontinence in Chinese middle-aged and older people. The risk of incontinence increases with decreasing handgrip strength. Handgrip strength should be measured in routine physical examinations in middle-aged and older people for timely assessment and intervention in incontinence.

One-stage implant in sacral neuromodulation for faecal incontinence - short-term outcome from a prospective study

AIM

Sacral neuromodulation (SNM) is approved for the treatment of faecal incontinence (FI) in a two-stage technique. With standardized implantation, approximately 90% of patients undergo successful Stage I operation and proceed to a permanent implant (Stage II). The aim of this work was to explore the feasibility of SNM as a one-stage procedure and report the 24-week efficacy.

METHOD

This study included patients diagnosed with idiopathic FI or FI due to an external anal sphincter defect ≤160° and one or more episodes of FI per week despite maximal conservative therapy. Patients were offered a one-stage procedure if a motor response of the external anal sphincter was achieved in three or more poles with at least one at ≤1.5 mA at lead placement. Patients were followed for 24 weeks. Their evaluation included the Wexner/St Mark's Incontinence Score, Faecal Incontinence Quality of Life score (FIQoL), a visual analogue scale (VAS) for assessing patient satisfaction and a bowel habit diary.

RESULTS

Seventy-three patients with a median age of 60 years (interquartile range 50-69 years) completed this prospective study. Episodes of FI were significantly reduced at the 24-week follow-up, from 13 (8-23) at baseline to 2 (0-5) (p-value = 0002). A ≥50% reduction in the number of FI episodes was achieved in 92% of participants. The Wexner score improved significantly from 16 (14-17) at baseline to 9 (5-13) (p-value < 0.001), and the St Mark's score improved significantly from 18 (16-20) to 11 (7-16) (p-value < 0.001). All domains in the FIQoL score and VAS for patient satisfaction improved significantly following the one-stage procedure.

CONCLUSION

A one-stage implantation procedure is feasible in selected patients with FI, significantly improving continence, quality of life and patient satisfaction after 24 weeks of follow-up.

Is magnetic anal sphincter augmentation still an option in fecal incontinence treatment: a systematic review and meta-analysis

PURPOSE

Magnetic anal sphincter (MAS) augmentation is a novel surgical option for the treatment of fecal incontinence. Current clinical evidence is conflicting. The purpose of this meta-analysis was to report the safety profile, potential benefits, and the functional efficacy of this device.

METHODS

The study followed the PRISMA guidelines. Literature databases (Medline, Scopus, Web of Science, CENTRAL) were screened for eligible articles. The primary endpoint was the pooled effect of MAS in the Cleveland Clinic Incontinence Score (CCIS) score. Quality evaluation was based on the ROBINS-I and Risk of Bias 2 tool.

RESULTS

Overall, 8 studies with 205 patients were included. MAS resulted in a significant reduction of CCIS values (p = 0.019), and improvement only in the embarrassment domain of FIQoL scores (p = 0.034). The overall morbidity rate was 61.8%. Postoperative adverse events included MAS explantation in 12%, infection in 5.1%, pain in 10% and obstructed defecation in 5.8% of patients.

CONCLUSION

The application of MAS in patients with fecal incontinence results in the improvement of some clinical parameters with a notable morbidity rate. Due to several study limitations, further, high-quality RCTs are required to delineate the efficacy and safety of MAS.

A Predictive Model to Identify the Effects of Transcutaneous Sacral Nerve Stimulation With Pelvic Floor Exercises in Fecal Incontinence After Surgery for Anorectal Malformation

INTRODUCTION

Although the combination of transcutaneous sacral nerve stimulation (tSNS) and pelvic floor exercises (PFEs) has shown significant effectiveness in treating fecal incontinence (FI) after surgery for congenital anorectal malformation (CARM), not all patients achieve satisfactory continence. Therefore, identifying which individuals will benefit from this method is crucial.

METHODS

A prospective cohort study enrolled 92 children with FI. All patients underwent tSNS with PFE treatment, and an improved outcome was defined as a Wexner score ≤4. A predictive model to identify the effects of tSNS with PFEs in FI was developed based on the analysis of magnetic resonance imaging and high-resolution anorectal manometry with area under the receiver-operating characteristic curve to evaluate the predictive value of external anal sphincter (EAS) thickness index and anal squeezing pressure (ASP).

RESULTS

tSNS with PFEs improved outcomes in 72 patients and led to poor outcomes in 20 (4 had their rectums deviate from the puborectalis muscle center or puborectal muscle ruptures while 16 lacked EAS with a lower ASP). The areas under the receiver-operating characteristic curve for EAS thickness index and ASP in predicting the effects of tSNS with PFEs were 0.915 (95% confidence interval 0.846-0.983, P = 0.000) and 0.886 (95% confidence interval 0.819-0.952, P = 0.000), respectively. By applying cutoff values of 0.076 for EAS thickness index and 21.95 mm Hg for ASP, tSNS with PFEs was found to be ineffective.

DISCUSSION

tSNS with PFEs is effective for most patients with FI after CARM surgery, except when the rectum deviates from the puborectal muscle center, puborectal muscle rupture occurs, or EAS is absent with a low ASP.

Simulation of artificial anal sphincter motion and interaction with intestinal environment using SOFA

BACKGROUND

Artificial anal sphincter is an implantable medical device for treating fecal incontinence. Reasonable simulation facilitates the advancement of research and reduces experiments on biological tissue. However, the device's clamping motion and sensor interaction with the intestine in the simulation still require further exploration. This article presents a simulation of the artificial anal sphincter's clamping and sensing and its interaction with the intestinal environment using the Simulation Open Framework Architecture (SOFA).

METHODS

Firstly, the proposed simulation algorithm and its principles in SOFA are analyzed. Secondly, the clamping motion and sensor system of the artificial anal sphincter are simulated. Thirdly, a finite element model of intestine is established based on the properties of intestinal soft tissue. Finally, the in vitro experiments are performed.

RESULTS

The simulation results indicate that the sensor system of the artificial anal sphincter has good sensing performance during the clamping motion and fecal accumulation process. Experiments have shown that optimal sensory capabilities can be achieved as the posture of the artificial anal sphincter with a roll angle between 20° and 40°. The comparison demonstrates a mean absolute error of 10%-20% between simulation and in vitro experimental results for sensor forces, which verifies the effectiveness of the simulation.

CONCLUSION

The proposed novel simulation achieves a more comprehensive interaction between the artificial anal sphincter motion and intestinal environment. This study may provide more effective simulation data for guidance in improving the performance of sensor perception of artificial anal sphincter for further research.

Association between calf circumference and incontinence in Chinese elderly

BACKGROUND

The objective of this study was to analyze the association between calf circumference and incontinence in Chinese elderly, and to find out the maximal cut-off point by gender for the use of calf circumference in screening for incontinence.

METHODS

In this study, participants were from the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS). The maximal calf circumference cut-off point and other incontinence-related risk factors were explored using receiver operating characteristic (ROC) curves and logistic regression analysis.

RESULTS

The study included 14,989 elderly people (6,516 males and 8,473 females) over 60. The prevalence of incontinence in elderly males was 5.23% (341/6,516), significantly lower than females, which was 8.31% (704/8,473) (p < 0.001). There was no correlation between calf circumference < 34 cm in males and < 33 cm in females and incontinence after adjusting the confounders. We further stratified by gender to predict incontinence in elderly based on the Youden index of ROC curves. We found the association between calf circumference and incontinence was the strongest when the cut-off points were < 28.5 cm for males and < 26.5 cm for females, with an odds rate (OR) value of 1.620 (male, 95%CI: 1.197-2.288) and 1.292 (female, 95%CI: 1.044-1.600) after adjusting the covariates, respectively.

CONCLUSIONS

Our study suggests that calf circumference < 28.5 cm in males and < 26.5 cm in females is a risk factor for incontinence in the Chinese elderly population. Calf circumference should be measured in routine physical examination, and timely interventions should be made to reduce the risk of incontinence in subjects with calf circumference less than the threshold.

Differences in Anorectal Manometry Values Among Women With Fecal Incontinence in a Racially, Ethnically, and Socioeconomically Diverse Population

IMPORTANCE

Anorectal manometry (ARM) is a valuable diagnostic and therapeutic tool that can both aid in identifying mechanisms contributing to fecal incontinence (FI) and inform management strategies. Consensus on standard reference range values has not been established, and women of varying racial and ethnic backgrounds are not well-represented in the current literature.

OBJECTIVE

We aimed to compare ARM values between women of different racial and ethnic groups with FI.

STUDY DESIGN

We conducted a retrospective cross-sectional study of women with FI who underwent ARM at a tertiary health system in an urban underserved community between 2016 and 2021. Demographic information and ARM values were collected from the medical record. Socioeconomic status (SES) was represented by the percent of the population living below the poverty line according to zip code using U.S. census data. Anorectal manometry values were compared between racial and ethnic groups, and multivariable logistic regression was conducted to control for patient characteristics.

RESULTS

Fifty-eight women were included in the analysis: 33% Hispanic, 22% Black, and 45% White. Hispanic and Black women had higher body mass index and higher rates of diabetes and loose stools and were of significantly lower SES compared with White women. Black and Hispanic women had significantly lower thresholds for volume at first sensation and higher mean anal squeeze pressure. Differences were maintained after controlling for body mass index, diabetes, SES, and diarrhea (P = 0.03 and P = 0.01, respectively). Other ARM values were not significantly different between groups.

CONCLUSIONS

Racial and ethnic differences in ARM values among women with FI exist. Further studies are needed to determine whether these differences have an impact on symptom severity, treatment selection and outcomes, and patient satisfaction.

Relationship between Incontinence and Disease Severity in Patients Transported by Ambulance

Introduction

Retrospectively investigated this relationship using data from Shimoda Fire Department.

Methods

We investigated patients who were transported by Shimoda Fire Department from January 2019 to December 2021. The participants were divided into groups based on the existence of incontinence at the scene or not (Incontinence [+] and Incontinence [-]). We compared the variables mentioned above between these groups.

Results

There were 499 cases with incontinence and 8241 cases without incontinence. There were no significant differences between the two groups with respect to weather and wind speed. The average age, percentage of male patients, percentage of cases in the winter season, rate of collapse at home, scene time, rate of endogenous disease, disease severity, and mortality rate in the incontinence (+) group were significantly greater in comparison to the incontinence (-) group, whereas the average temperature in the incontinence (+) group was significantly lower than that in the incontinence (-) group. Regarding the rates of incontinence of each disease, neurologic, infectious, endocrinal disease, dehydration, suffocation, and cardiac arrest at the scene had more than twice the rate of incontinence in other conditions.

Conclusions

This is the first study to report that patients with incontinence at the scene tended to be older, showed a male predominance, severe disease, high mortality, and required a long scene time in comparison to patients without incontinence. Prehospital care providers should therefore check for incontinence when evaluating patients.

Effects of neuromodulation on treatment of recurrent anal fissure: A systematic review

BACKGROUND

Anal fissure is a linear tear in the distal anoderm most frequently occurring in the posterior midline. Lateral internal sphincterotomy is considered the gold standard for the treatment of this condition. To this date, several pharmacological and neuromodulatory therapies have been tried out as alternative non-invasive treatments for anal fissures, however, the efficacy of some of these methods remains to be understood.

OBJECTIVE

the primary aim of this study was to review available literature on neuromodulatory treatments for recurrent anal fissure as a potentially effective cure for this condition.

DATA SOURCES

A search was conducted among five main online databases Embase, PubMed, Web of Science, Scopus, and Scholar.

STUDY SELECTION

All published human studies in English literature addressing neuromodulation for the treatment of recurrent anal fissure were selected.

INTERVENTION

neuromodulation for the treatment of anal fissure. We chose to include all articles in which the authors stated that the procedure they performed was via neuromodulation technique, or that the described technique used in their study resembled the technique.

RESULT

Among a total of 3487 evaluated studies, seven represented the effects of neuro modulation on treatment of recurrent anal fissure, among which two were randomized controlled trials and the rest were prospective studies. A total of 186 patient were evaluated in these studies. The mean age of the participants was 46.97 ± 8.2. The average VAS score before intervention was 7.77 ± 2.13, which decreased to 0.31 ± 1.13 after intervention.

LIMITATIONS

limitations of this study include the lack of related articles, and data regarding this subject.

CONCLUSION

Posterior tibial nerve stimulation (PTNS) provides rapid pain relief and fissure healing especially in short-to mid-terms with little to no complications, however, using this treatment, symptoms of anal fissure do not improve as well as LIS, especially in the long-term.