Selective serotonin reuptake inhibitor-induced urinary incontinence

Irrespective of its cause, urinary incontinence is a medical condition seriously affecting quality of life and is increasingly recognized. In this study, we examined the association between the use of selective serotonin reuptake inhibitors (SSRIs) and urinary incontinence.

A retrospective follow-up study among starters with an SSRI was performed to estimate the relative and absolute risk for urinary incontinence associated with SSRI use. Data came from the PHARMO database, which includes information on drug dispensing for approximately 450,000 residents living in eight Dutch cities. All patients initially using an SSRI between 1994 and 1998 were selected. The frequency measures for urinary incontinence were estimated by using prescription sequence analysis, where initiation of spasmolytic drugs or absorbent products was used as a measure for urinary incontinence. Besides crude incidence density calculations, Andersen-Gill's model was used in order to control for possible confounding factors and time varying covariates.

A total of 13,531 were identified as first time users of an SSRI. Compared to non-exposure, the incidence density ratio for urinary incontinence during SSRI exposure was 1.75 (95% CI 1.56-1.97). Overall, compared to baseline, SSRI use caused 14 extra cases of urinary incontinence per 1000 patients treated per year; the elderly were more at risk resulting in 60 extra cases per 1000 patients per year. The adjusted relative risk for urinary incontinence due to SSRI use was 1.61 (95% CI 1.42-1.82); the risk for sertraline users was 2.76; 95% CI 1.47-5.21).

Exposure to SSRIs is associated with an increased risk for developing urinary incontinence, which can be explained pharmacologically. Approximately 15 out of 1000 patients treated per year with an SSRI developed urinary incontinence. The elderly and users of sertraline are at the highest risk.