Spaying and urinary incontinence in bitches under UK primary veterinary care: a case–control study

OBJECTIVES: To evaluate associations between spaying and urinary incontinence in bitches under primary veterinary care in the UK. MATERIALS AND METHODS: A case–control study was nested within the study population of 333,910 bitches, which included all bitches within the VetCompass database with an electronic patient record in 2016 or in both 2015 and 2017. The electronic records were searched automatically for urinary incontinence cases, which were manually reviewed for inclusion. All non‐cases were included as controls. Additional demographic and clinical information was extracted on cases and controls. RESULTS: The study included 427 incident cases and 1708 controls that were presented between November 1, 2014 and October 31, 2017. Prior spaying was associated with increased odds of urinary incontinence (odds ratio: 3.01; 95% CIs: 2.23 to 4.05). Increased odds of urinary incontinence were additionally associated with increasing age and increasing bodyweight. Age at spay was not associated with urinary incontinence. CLINICAL SIGNIFICANCE: The findings support spaying as a major risk factor associated with urinary incontinence, but age at spay appears to be of less clinical importance. These results will help assist clinicians in making evidence‐based recommendations on spaying while taking other considerations for urinary incontinence into account.