RESUMEN
BACKGROUND: To date, standard recommendations for the management of stress urinary incontinence (SUI) would be either pelvic floor muscle training (PFMT) or surgery. A new form of drug treatment with a serotonin-noradrenaline reuptake inhibitor (SNRI), duloxetine, may now have a place in treatment of this condition. OBJECTIVES: To determine whether a SNRI is better than placebo (or no treatment, other pharmacological and non-pharmacological therapies, or surgery) in the treatment of women with SUI, or mixed urinary incontinence that includes stress incontinence (MUI), or both and which doses should be used. SEARCH STRATEGY: We searched the Cochrane Incontinence Group specialised register (searched 1 December 2004), (CENTRAL) (Issue 2, 2004), MEDLINE (January 1966 to September 2004), PREMEDLINE (11 March 2004), Dissertation Abstracts and the reference lists of relevant articles. SELECTION CRITERIA: All randomised or quasi-randomised controlled trials of treatment for SUI or MUI, in which at least one management arm involved a SNRI. DATA COLLECTION AND ANALYSIS: Two authors evaluated the trials for appropriateness for inclusion and methodological quality. Three authors performed the data extraction using predetermined criteria. Analyses were performed using the Cochrane Review Manager software, RevMan. MAIN RESULTS: Nine randomised trials were included, involving 3327 adults with predominantly SUI, randomised to receive duloxetine or placebo. Both arms in individual trials were comparable for various baseline characteristics. Treatment duration was between three weeks and 12 weeks. Duloxetine was significantly better than placebo in terms of improving patients' quality of life (WMD 5.26, 95%CI 3.84 to 6.68. P< 0.00001) and perception of improvement. Individual studies demonstrated a significant reduction in the Incontinence Episode Frequency (IEF) by approximately 50% during treatment with duloxetine. With regard to objective cure, however, meta-analysis of stress pad test and 24 hour pad weight change failed to demonstrate a benefit for duloxetine over placebo though data were relatively few. Subjective cure favoured duloxetine, albeit with a small effect size (3%). One trial suggested that duloxetine was better than pelvic floor muscle training alone in reducing IEF (P < 0.05) based on median percentage decrease in IEF per week. Although significant side effects were commonly associated with duloxetine, they were reported as acceptable. AUTHORS' CONCLUSIONS: The available evidence suggests that duloxetine treatment can significantly improve the quality of life of patients with stress urinary incontinence, but it is unclear whether or not benefits are sustainable. Adverse effects are common but not serious. About one in three participants allocated duloxetine reported adverse effects (most commonly nausea) related to treatment, and about one in eight allocated duloxetine stopped treatment as a consequence.