2021-08-17
Tatsuya Abe, Masao Kunimoto, Yoshikazu Hachiro, Yoshiaki Ebisawa,
Houhei Hishiyama and Masanori Murakami
Keywords: Fecal incontinence; calcium polycarbophil; pharmacotherapy; stool form scale
1. INTRODUCTION
Fecal incontinence (FI) is a psychologically distressing and disabling condition that has a significant impact on the quality of life and poses a large economic burden. Non-operative therapy is generally the first approach to improve FI symptoms, and the addition of a daily fiber supplement, which acts as a bulking agent to allow for more solid stools, are advised in its management. A randomized, blinded, placebo-controlled study found that daily fiber supplementation improved FI and stool consistency.
In addition to fiber supplementation, pharmacologic agents with a constipating effect, including loperamide, diphenoxylate, atropine, and codeine, may be useful for patients with FI. Of these, loperamide is the most commonly used with proposed additional beneficial effects on the anal sphincter resting tone. Although loperamide has been shown as particularly useful in patients with diarrhea and urge-related FI, its use in other FI types is often associated with unsatisfactory results.
FI is commonly exacerbated by watery stools or diarrhea; however, it may also arise as a consequence of chronic constipation. In some patients, prolonged rectal retention or incomplete evacuation of the stool may lead to stool seepage or soiling of undergarments. A majority of these patients suffer from obstructive or dyssynergic defecation, and many additionally exhibit impaired rectal sensation. Similarly, in the elderly and children with functional incontinence, the prolonged rectal retention of stool can lead to fecal impaction.
Calcium polycarbophil (CP) is an insoluble, synthetic hydrophilic polymer. Studies in canines demonstrated that CP could absorb up to 70 times its own weight in fluid, improve stool consistency, and decrease the frequency of bowel movements. Alternatively, in a constipation model, CP was shown to increase stool frequency and fecal weight. Although CP is recommended as an ideal and initial bulk- forming agent in patients with FI, there are relatively few clinical studies defining the effect of CP on FI. Therefore, we reviewed the outcomes of CP treatment in patients with FI at our institution.
2.MATERIALS AND METHODS
Prospectively collected data from patients with FI treated with CP (Polyful®, Mylan, Tokyo, Japan) at our institution between January 2005 and December 2014 were retrospectively reviewed. The inclusion criteria were the presence of at
least one FI episode per month for at least 3 consecutive months. The exclusion criteria were the presence of current rectal prolapse, active perineal sepsis, diagnosis of anorectal tumor, and treatment with additional therapeutic modalities. Patients previously treated with other modalities were included if they received CP during the enrollment period.
In all patients, the data collected included demographics, risk factors for FI (anorectal surgery, obstetric-related trauma, systemic neurologic disorder, or spinal pathology), and a completed comprehensive symptom question- naire. The questionnaire assessed both the nature and frequency of FI episodes and the patterns of defecation, including laxative use and stool form by the Bristol Stool Form Scale, which is a medical aid designed to classify the form of human feces into seven categories. Types 1 and
2 indicated constipation, and types 3 and 4, mostly the latter, described ideal stools. Types 5, 6, and 7 indicated soft to watery stools. FI was additionally classified into passive incontinence (defecation without the patient’s knowledge), urge incontinence (failure to defer defecation for 15 min), or mixed incontinence (a combination of passive and urge incontinence). The severity of FI was assessed with the grading system of the Cleveland Clinic Incontinence Score (CCIS), ranging from 0 (complete continence) to 20 (complete incontinence). The potential underlying causes of FI were determined by questionnaires and anorectal physiologic tests.
All patients underwent comprehensive anorectal physiologic tests with the rectum unprepared. Anorectal manometry (ARM) was performed using a 5-mm diameter, 1- channel, solid-state catheter with a microtipped transducer ARM system. The lubricated catheter was introduced into the rectum, with the patient in the left lateral
position with the hips flexed to 90°. The maximal resting pressure (MRP) was recorded by means of a rapid pull-through technique and was defined as the highest resting pressure recorded. Subsequently, the maximal squeeze pressure (MSP), defined as the highest pressure recorded above the baseline (zero) at any level of the anal canal during maximum squeeze effort by the patient, was measured. Next, each patient was evaluated by endoanal ultrasound scanning (EAUS) with a scanner that has a 7-MHz rotating endoprobe. The questionnaires and anorectal physiologic tests were routinely used in our clinical practice.
All patients received oral CP tablets at a dose of either 1.0 g three times per day (3.0 g per day) or 0.5 g three times per day (1.5 g per day), as needed based on age, perceived severity of incontinence, and need for relief, or at the clinician’s discretion. The medications were taken with at least one glass of water after meals. Most patients were encouraged to perform Kegel exercises at home to strengthen the puborectalis muscle and the external anal sphincter. The primary efficacy measures of this study were the CCIS and the stool consistency. Patients were evaluated before and after 1 month of therapy.
The data were expressed as mean ± standard deviation for quantitative variables. In the figures, the means were plotted with standard errors. Paired analysis was performed using paired t- test. Two-tailed P values of less than 0.05 were considered significant.
