Epidemiological study of feline idiopathic cystitis in Seoul, South Korea.

Objectives The objective of this study was to investigate potential risk factors for the diagnosis of feline idiopathic cystitis (FIC) in cats living in a primarily indoor environment. Methods A case-control study focusing on a cohort of cats attending a first-opinion veterinary practice in Seoul, South Korea, from 2012-2016, was undertaken. Data were collected from cats' owners by questionnaire and analysed using a multivariable logistic regression analysis. Results Fifty-eight cases of FIC and 281 randomly selected controls were surveyed. Over 90% of the cases and controls had no access to the outside, and 100% and 91% of the cases and controls, respectively, were neutered. The estimated prevalence of an FIC diagnosis was 1.77% (95% confidence interval [CI] 1.36-2.18). The final logistic regression model included five variables associated with an FIC diagnosis. Males had 2.34 times the odds of being diagnosed with FIC compared with females (95% CI 1.18-4.62; P = 0.015). Cats reported as not having vantage points had 4.64 times the odds of an FIC diagnosis compared with those reported as having vantage points (95% CI 2.05-10.49; P <0.001). Cats living in an apartment had 2.53 times the odds of an FIC diagnosis compared with those living in a house (95% CI 1.30-4.93; P = 0.006). Cats cohabiting with other cats were more likely to be diagnosed with FIC than those living alone (odds ratio 3.16, 95% CI 1.61-6.22; P = 0.001). Cats using non-clumping litter had 2.62 times the odds of an FIC diagnosis compared with those using clumping litter (95% CI 1.38-4.96; P = 0.003). Conclusions and relevance This study was conducted in a different epidemiological context from previous studies in that the overwhelming majority of the cats studied were housed entirely indoors. This study identified several significant associations related to a cat's indoor environment. These findings suggest that the cat's physical and social environment may play a role in the development of FIC.