Examining the Evidence
Does electrical stimulation aid muscle training for stress incontinence?
To determine whether pelvic floor electrical stimulation (PFES) improves outcomes of multicomponent behavioral training for stress incontinence.
Electrical stimulation did not significantly improve outcomes.
Two hundred community-dwelling women with stress incontinence were randomized to 1 of 3 groups for an 8-week period: 1) biofeedback-assisted pelvic floor muscle training (PFMT), home exercises, bladder control strategies, and self-monitoring with bladder diaries; 2) the same program plus home PFES (15 minutes every other day, alternating with home exercises); or 3) self-administered behavioral training consisting of a self-help booklet and bladder diaries.
Intention-to-treat analysis revealed that frequency of incontinent episodes was reduced by 68.6% in group 1, 71.9% in group 2, and 52.5% in group 3. Attrition rates for the 3 groups were 18.2%, 11.9%, and 37.3%, respectively. Efficacy analysis, which examined only those completing treatment (n = 155), showed no significant differences among the groups on reduction of incontinence episodes. Patients in the PFES group reported more satisfaction with their progress, suggesting some placebo effect.
The strength of this timely study is its design: a prospective randomized controlled trial with a large sample size and adequate power. It suffers, however, due to its short-term follow-up and a significantly greater attrition rate in the control group.
Only 2 prior studies have evaluated the effect of electrical stimulation as an adjunct to PFMT for stress incontinence. A study of 14 patients showed that the addition of electrical stimulation improved outcome of physiotherapy. 1 Another study found the addition of both biofeedback and electrical stimulation improved symptoms and muscle strength, but the study did not isolate the effects of PFES as a single adjunct.2
Patient compliance is vital to the success of behavioral therapy. The motivated patient with adequate neuromuscular function will improve with PFMT, with or without adjunctive therapy, and thus may forego surgical intervention. Less motivated patients, those who lack awareness of pelvic floor muscles, or those with decreased pelvic floor function may achieve greater success with adjunctive therapy, be it biofeedback or PFES. Still, long-term efficacy of such therapies is not known.
1. Blowman C, Pickles C, Emery S, et al. Prospective double blind controlled trial of intensive physiotherapy with and without stimulation of the pelvic floor in treatment of genuine stress incontinence. Physiotherapy. 1991;77:661-664.
2. Sung MS, Hong JY, Chol YH, et al. PFES biofeedback versus intensive pelvic floor muscle exercise for the prevention and treatment of genuine stress incontinence. J Korean Med Sci. 2000;15:303-308.