OC-007 Double blind randomised controlled trial of percutaneous tibial nerve stimulation for the treatment of faecal incontinence in adults

Abstract

<h3>Introduction</h3> Percutaneous Tibial Nerve Stimulation (PTNS) is a relatively new ambulatory therapy for faecal incontinence. Case series data suggest beneficial outcomes in 50–80% patients however the effectiveness of PTNS vs. sham has not been trialled. We aimed to assess the short-term efficacy of PTNS compared to sham electrical stimulation in adults with faecal incontinence. <h3>Method</h3> In this multicentre, parallel-group, double-blind, randomised controlled trial involving 17 UK specialist centres, patients aged 18 years or over with significant faecal incontinence, who had failed conservative treatments were randomly assigned (1:1) to receive either PTNS or sham electrical stimulation. Randomisation was stratified by sex and then by centre in females. Patients and outcome assessors were masked to allocation for the 14-week duration of the trial when the effect of the intervention on severity of FI and quality of life was assessed using bowel diaries and validated questionnaires. A clinical response to treatment (primary outcome) was defined as a ≥50% reduction in weekly FI episodes. Secondary outcomes included reduction in mean weekly FI episodes, summative symptom scores, disease-specific and generic quality of life measures. ISRCTN registration number: 88559475. <h3>Results</h3> 227 patients were randomised (from 373 screened) to receive PTNS (n = 115) or sham stimulation (n = 112). 12 patients withdrew; 7 from the PTNS group and 5 from the sham group. Missing data were multiply imputed. 39 patients in the PTNS group (38%) had a 50% or greater reduction in weekly FI episodes compared to 32 in the sham group (31%) (OR 1.28, 95% CI 0.72–2.28, p = 0.396). There was a significantly greater decrease in mean total weekly FI episodes in the PTNS compared to sham group (difference in means –2.3, 95% CI (–4.2 to –0.3), p = 0.02). This reflected a significant reduction in mean weekly urge (–1.5, 95% CI (–2.7 to –0.2), p = 0.02) but not passive episodes (–0.64, 95% CI (–1.67 to 0.40), p = 0.23). No significant difference in St Mark’s Continence Score was observed between groups (difference in means –0.047, 95% CI (–1.033 to 0.939), p = 0.93). No differences in the disease-specific Faecal Incontinence Quality of Life and Gastrointestinal Quality of life tools or the generic SF-36 quality of life tool were observed between the groups. No serious adverse events related to treatment were reported. <h3>Conclusion</h3> PTNS did not confer significant clinical benefit over sham electrical stimulation in the treatment of adults with faecal incontinence. <h3>Funding</h3> This project was funded by the NIHR Health Technology Assessment programme. <h3>Disclosure of interest</h3> None Declared.