Sa1373 Significant Findings From a Randomised Control Trial of Posterior Tibial Nerve Stimulation in Systemic Sclerosis Associated Faecal Incontinence

Abstract

Background The gastrointestinal tract is affected in up to 90% of Systemic Sclerosis (SSc) patients with faecal incontinence (FI) being reported in up to 38%. Passive faecal incontinence secondary to internal anal sphincter atrophy is the characteristic finding. We have shown that neuropathic changes are implicated in SSc patients with FI and sacral nerve stimulation has emerged as a potentially beneficial therapy in SSc. However this is expensive, invasive, not widely available and we have shown that medium term efficacy is poor. Posterior tibial nerve stimulation (PTNS) is a potential alternative to modulate the sacral plexus indirectly, with none of these disadvantages. This is the preliminary data on a randomized placebo controlled trial of PTNS versus sham PTNS to determine if nerve modulation is an effective treatment in SSc associated FI. Methods We commenced a prospective randomised singleblind study of SSc patients with FI in February 2013 from a specialist Scleroderma unit. Baseline symptom scoring (bowel diary, Wexner), manometry and endoanal ultrasound were completed prior to randomization to PTNS or sham. PTNS was administered conventionally, by insertion of an acupuncture needle according to anatomical landmarks, connected to an electrical stimulator. Sham PTNS was administered in identical fashion but the PTNS surface electrode was not connected and instead separate TENS surface electrodes were connected to a TENS unit. Each patient underwent blinded intervention for 30 minute periods, once a week for 12 weeks. The primary endpoints were reduction in faecal incontinence episodes/ week and a reduction in Wexner incontinence scores. A Wexner responder was defined as a post-treatment reduction in score to ≤ 10 with the maximum score at 20. Results A total of 23 SSc patients (20 f), mean age 62 (41-82) completed the trial by October 2014. Of these 12 (10 f) underwent PTNS and 11 (10 f) patients underwent sham stimulation. All PTNS patients showed a reduction in the number of FI episodes/week when compared to SHAM patients at 12 weeks (p=0.0025) (plot 1). 6/12 (50%) PTNS patients were Wexner responders compared to 0/11 SHAM patients with the% change inWexner score significantly reduced in the PTNS group (p=0.0019) (plot 2). Conclusion. Our results demonstrate significant short-term benefits of PTNS in SSc associated FI. This argues for a neuropathic and reversible cause for incontinence in SSc. PTNS could be considered as an alternative to permanent SNS placement.