A prospective observational cohort study of posterior tibial nerve stimulation in patients with multiple sclerosis: design and methods.

BACKGROUND: Posterior tibial nerve stimulation (PTNS) is a promising treatment for lower urinary tract symptoms (LUTS) in patients with MS. However, long term data focusing on PTNS impact on health-related quality of life (HRQOL), bowel and bladder symptoms are lacking. This paper describes a study protocol that examines the extended efficacy of PTNS on MS related bladder and bowel symptoms and resulting HRQOL. METHODS/DESIGN: This is a single-centered, prospective, longitudinal, observational cohort study of patients with MS who suffer from LUTS and are refractory to two prior treatment modalities. Participants who have elected to pursue PTNS therapy for LUTS will be eligible. The primary outcome is the median number of urinary frequency and incontinence episodes on a 3-day voiding diary at 3, 12 and 24 months compared to baseline. Secondary outcome measures will include change in total AUA-SS, M-ISI, NBSS, SF-12, SSS and BCS scores from baseline The Expanded Disability Status Scale and magnetic resonance imaging will be evaluated at baseline and annually throughout the study. DISCUSSION: This research protocol aims to expand on the existing literature regarding outcomes of PTNS in MS. Specifically, it will provide long term follow-up data on bladder, bowel, sexual and HRQOL outcomes. The completion of this study will provide longitudinal efficacy data of the impact of PTNS in MS patients. TRIAL REGISTRATION: NCT04063852.