Sacral nerve stimulation in fecal incontinence: Are there factors associated with success?

PURPOSE: Sacral nerve stimulation has been used successfully in treating fecal incontinence. This study was designed to evaluate the proportion of patients with unsuccessful implantation despite positive test stimulation and to examine and compare factors associated with the success of the transitory and permanent sacral nerve stimulation. METHODS: A total of 61 patients (55 females; median age, 56 (range, 33-77) years) with refractory fecal incontinence underwent temporary stimulation. A 50 percent or greater improvement in the number of episodes of fecal incontinence or urgency was required to proceed to permanent implantation and was the criteria of success of permanent sacral nerve stimulation at the last follow-up visit in implanted patients. The factors compared between the success and the failure groups during temporary and permanent stimulation were patients' age and gender, diagnosis and characteristics of fecal incontinence, previous surgery, quality of life scores, anorectal manometry, endoanal ultrasound, and electrophysiologic tests performed before stimulation. RESULTS: Temporary stimulation was successful in 35 patients (57.4 percent). A permanent neurostimulation device was implanted in 33 patients. Age was the only factor related to success of the temporary stimulation (P = 0.03). After permanent implantation, 31 percent of patients did not attain screening phase results for the number of episodes of fecal incontinence or urgency. A neurologic disorder was more frequently the origin of fecal incontinence in the success group compared with others (P = 0.03). The left bulbocavernosus reflex was more frequently delayed in the success group than in the others (P = 0.03), and a prolonged or absent bulbocavernosus reflex was more frequent in the success group than in the failure group (P=0.03). CONCLUSIONS: Patients with fecal incontinence from neurologic origins could be good candidates for sacral nerve stimulation.