Efficacy of cyclic sacral nerve stimulation for faecal incontinence

Background Sacral nerve stimulation (SNS) is an established treatment option for faecal incontinence. Cyclic stimulation will improve the longevity of the implanted stimulator, but little is known about its efficacy. The aim of this retrospective clinical study was to assess the efficacy of cyclic SNS for faecal incontinence. Sixty-three patients underwent percutaneous nerve evaluation (PNE) test with a 2-week period of continuous SNS. The PNE test was deemed positive in 42 patients (67 %) who underwent implantation with permanent stimulator. All 42 patients were initially stimulated in a cyclic manner with stimulation for 20 s followed by 8 s without. During follow-up, the stimulator was explanted in 2 patients and permanently turned off in one due to the loss of effect. A postal questionnaire including the Wexner score, a general quality of life (Qol) score, and a bowel habit diary was distributed to 39 patients. The questionnaire was returned by 29/39 (74 %) of the patients. Median duration of follow-up was 16 (range 3-34) months. The Wexner score and the general QoL score were significantly improved compared to pre-treatment values. Some 18 patients (62 %) were still treated with cyclic stimulation at follow-up, reporting more frequent episodes of urgency without incontinence (p = 0.020) compared to symptoms during the PNE test. Patients who had changed to continuous stimulation due to a suboptimal effect during follow-up reported more frequent episodes of urgency with incontinence (p = 0.034), minor soiling (p = 0.045) and days wearing pads (p = 0.027) compared with symptoms during the PNE test. Cyclic stimulation seems effective for most patients treated with SNS for faecal incontinence.