Usefulness of Patient-Reported Outcome Measures and Anorectal Physiologic Tests in Predicting Clinical Outcome for Fecal Incontinence

Abstract

Fecal incontinence (FI) is one of the most intractable diseases for colorectal surgeons. Although many reports have been published, the pathophysiology of FI is not yet fully understood, and its cause is often difficult to identify. Treatment of FI includes conservative and surgical treatments with the aim of improving symptoms and patients’ quality of life (QoL). Surgical treatment for FI is generally considered in a small number of patients who have failed to respond to conservative treatment. However, the choice of conservative or surgical treatment has depended on the decision of the individual physician, as few studies have revealed objective tools for the selection of surgical treatment. Numerous surgical methods, including anal sphincter repair, an artificial anal sphincter, and sacral nerve stimulation (SNS), have been proposed to treat FI. Wald [1] reported on the uncertain effect of the traditional surgical technique, anal sphincter repair, and noted that short-term results showed improvement in up to 85% of patients with FI while long-term results showed a failure rate of more than 50% after 40 to 60 months, which increased further thereafter [2, 3]. The author also reported that the effects of treatment deteriorated over time, especially in older patients. O’Brien et al. [4], in a prospective, randomized, controlled study, reported the effect of an artificial anal sphincter on patients with severe FI. In the artificial anal sphincter group (7 patients) and the control group (7 patients), the Wexner Incontinence Scores were compared before and after 6 months of treatment. At 6 months, a significant difference was found between the groups (artificial anal sphincter group vs. control group: from 19.0 to 4.8 vs. from 17.1 to 14.3, P = 0.002). However, this was the result of only 14 patients. Benezech et al. [5] mentioned that the artificial sphincter had a high rate of complications, but a moderate effect, which, in turn, limited its use for treating patients with FI. Thaha et al. [6] reported a systemic review on the efficacy of SNS for treating patients with FI. The authors selected all randomized trials assessing the effects of SNS for treating FI in adults. They found limited evidences from the trials and suggested that a proportion of patients with FI could be improved by using SNS. Therefore, the authors emphasized the need for strict high-quality randomized trials to better assessment the effects of SNS. At present, the evaluation of FI also requires high-quality evidence. Although studies have predicted the effectiveness of each treatment of FI, the tools used to assess the effectiveness were not integrated and varied from subjective patient-reported outcome measures (PROMs) to physiologic tests, including anorectal manometry (ARM). Whether these subjective scoring systems or physiologic tests including ARM would be better as a measure to help predict the appropriate treatment for FI is not clear yet. What is the usefulness of PROMs and anorectal physiologic tests in predicting the clinical outcome for patients with FI? Ramage et al. [7] conducted a very meaningful study, perhaps the first study using ARM to predict the need for surgery in patients with FI. The authors assessed the usefulness of ARM and PROMs in predicting the need for surgery in 276 patients with FI. Two hundred twenty-eight patients (82.6%) underwent conservative treatment, and 48 patients (17.4%) underwent surgery. On binomial regression analyses, age, male sex, ARM including maximal resting pressure, 5-second squeeze increment, threshold volume to distension, urge volume to distension, all domains of the Birmingham Bowel and Urinary Symptoms Questionnaire (BBUSQ), the Wexner Incontinence Score, and all domains of the Short Form 36 (SF-36) were factors predictive of the need for surgery. Receiver operating characteristic curve analyses showed that Correspondence to: Chang-Nam Kim, M.D. Department of Surgery, Eulji University Hospital, Eulji University School of Medicine, 95 Dunsanseo-ro, Seo-gu, Daejeon 35233, Korea Tel: +82-42-259-1335, Fax: +82-42-259-1335 E-mail: [email protected] ORCID code: https://orcid.org/0000-0001-7781-9119