Risk factors for endoparasitism in dogs: retrospective case-control study of 6578 veterinary teaching hospital cases.

OBJECTIVES: The diagnostic utility of routine faecal examinations can be greatly enhanced through an appreciation of risk factors most commonly associated with endoparasitism.
METHODS: From a sample of 6578 canine patients presenting to a veterinary teaching hospital between 1996 and 2006, this study used univariate and multi-variable techniques to examine putative signalment, medical history and demographic factors predisposing dogs to intestinal parasites.
RESULTS: Age and median household income were the strongest predictors of endoparasitism. The odds of a patient being diagnosed with endoparasites were 0.82 times smaller for every 1 year increase in age (OR=0.82, 95% CI: 0.80 to 0.84) and for every $10,000 increase in median household income, the odds were 0.86 times lower (OR=0.86, 95% CI: 0.83 to 0.89). The variables gender, neuter status, month of diagnosis, admitting clinical service and primary diagnosis were not significant predictors. Animals that were presented for underlying medical conditions were less likely to have parasites and the presence of diarrhoea was associated with 76% lower odds of endoparasitism compared to healthy animals (OR=0.76, 95% CI: 0.64 to 0.90). CLINICAL SIGNIFICANCE: Clinicians should maintain a high index of suspicion for parasites in younger patients that live in high population density and low income neighbourhoods.