Objective: To analyze by meta-analysis the results of randomized controlled clinical trials on the efficacy of estrogen treatment in menopausal patients with urinary incontinence.
Study design: Meta-analysis.
Materials and methods: Randomized controlled clinical trials, published from January 1965 to December 1996, on estrogen therapy in patients with urinary incontinence, were selected. They included: trials with placebo vs estrogen therapy, studies on menopausal patients with confirmed diagnosis of urinary incontinence based on clinical and/or urodynamic tests, studies with sufficient statistical informations on the results obtained and with information about subjective and objective outcome.
Results: Out of 72 articles reviewed, 7 were selected and only 4 were considered on the basis of the requested criteria. Subjective outcome was statistically different in patients treated with estrogen therapy compared with patients treated with placebo. Objective clinical and urodynamic outcome was not statistically different in the two types of treatment (estrogen vs placebo treatment).
Conclusions: There were few published randomized controlled studies on estrogen therapy in patients with urinary incontinence in medical literature. Different results between subjective and objective outcome showed by meta-analysis, could be explained either by an estrogen induced unperceivable improvement not registered by clinical and instrumental parameters or by insufficient systems used to collect subjective data. Therefore, it is suggested that, for future research, randomized controlled clinical trials on topical or transcutaneous systemic estrogen treatment with a more than 6 months follow-up will be carry out.