Outcome of percutaneous tibial nerve stimulation (PTNS) for fecal incontinence: a prospective cohort study.

Objectives: The aim of this study was to assess the long-term efficacy of percutaneous tibial nerve stimulation (PTNS) in fecal incontinence (FI).

Background: There is extensive evidence regarding the efficacy of PTNS in urinary incontinence. Data on the efficacy of PTNS for FI are limited to a few small case series with relatively short-follow up.

Methods: A prospective cohort of patients with FI was studied. Incontinence scores were measured using a validated questionnaire (Cleveland Clinic Florida-FI score) at specific time points: before treatment, after completion of a treatment course (12 PTNS sessions), and before the last maintenance ("top-up") therapy. Deferment time and average number of weekly incontinence episodes were also estimated from a prospective bowel dairy kept by the patient at these time points. Quality of life was assessed with the Rockwood Fecal Incontinence Quality of Life questionnaire.

Results: A total of 150 patients were recruited to the study between January 2008 and June 2012. Analysis was performed on 115 patients who continued to receive PTNS after a median follow-up of 26 (range, 12-42) months. The baseline Cleveland Clinic Florida-FI score ±SD (12.0 ± 3.9) improved after 12 PTNS sessions (9.4 ± 4.6, P < 0.0001) and after "top-up" treatments (10.0 ± 4.3, P < 0.0001). The increase in the Cleveland Clinic Florida-FI score between the end of the 12th session and the last "top-up" therapy was also significant (P = 0.04). A similar pattern was seen for the deferment time and the quality of life scores. The median time between "top-up" sessions was 12 months (range, 1-40 months), significantly longer than the recommended interval of 6 months.

Conclusions: PTNS is a well-tolerated treatment with high acceptability in the majority of patients. It provides a sustained improvement in FI up to 42 months in a relatively noninvasive manner. The effect of PTNS diminishes with time and additional therapy sessions at 6 monthly intervals may result in greater improvements. PTNS ought to be considered as the first step in all patients with FI refractory to maximum conservative therapies.