A prospective, randomized study: Switch off the sacral nerve stimulator during the night?

PURPOSE: Sacral nerve stimulation is an effective treatment for fecal incontinence. Some have recommended to switch off the pacemaker during the night to extend the lifetime of the expensive pacemaker. This study was designed to investigate whether a nightly switch off affects the clinical results of sacral nerve stimulation. METHODS: Twenty patients successfully treated with sacral nerve stimulation (19 females; median age, 59 (range, 36-72) years) were randomized to: Group A, pacemaker continuously on for three weeks followed by three weeks with the pacemaker off during the night, or Group B, opposite order. Daily bowel-habit diary, Wexner, and St. Mark's incontinence scores were obtained. RESULTS: One failed to return the daily bowel-habit diary, leaving 19 participating patients. Median Wexner incontinence score increased from 6 (range, 2-14) to 7 (range, 3-16) during the off period (P=0.04), whereas St. Mark's incontinence score increased from 10 (range, 3-16) to 11 (range, 3-18; P=0.03). Median number of days with soiling per three weeks increased from 0 (range, 0-12) to 1 (range, 0-15) during the off period (P=0.008). Seven of 19 had more days with soiling during the off period. Defecation frequency per three weeks increased from 26 (range, 11-71) to 34 (range, 9-70) during the off period (P=0.19). Only four continued with a nightly switch off after the study. CONCLUSIONS: It could be considered to recommend compliant patients to switch off the pacemaker during the night to extend the lifetime of the pacemaker. One-third experienced increased soiling, and they should turn the pacemaker on all day and night. Among the remaining, only a minor proportion will be motivated for turning the pacemaker off.