The relationship between urinalysis abnormalities, soiling behavior, and cognitive decline in aging dogs.

Abstract

Background: In elderly people, dementia and urinary tract dysfunction often exacerbate one another. Aging dogs also suffer cognitive decline but the relationship between cognitive decline, soiling behaviors, and urinalysis abnormalities has not been explored.

Hypothesis/objectives: Soiling behavior is associated with urinalysis abnormalities and cognitive performance in aging dogs.

Animals: Eighty-four client-owned dogs enrolled in a longitudinal cohort study of aging.

Methods: In this prospective observational study, dogs were evaluated biannually with free-catch urinalysis, owner-completed Canine Dementia Scale (CADES), and a cognitive test battery. Mean age at enrollment was 12.77 years ± 1.91, 53 were female spayed, 29 male neutered, and 1 female and 1 male intact. Mixed-effects and generalized linear mixed models were used to assess the associations between urinalysis variables and cognitive test performance.

Results: Of 231 urinalyses, 19 showed pyuria, 14 hematuria, 11 bacteriuria, and 194 proteinuria. Urine specific gravity (USG) ranged from 1.005 to 1.056 and decreased significantly with age (P < .001). Soiling scores ranged from 0 to 25, and were associated with increasing age (P < .001) and decreasing USG (P < .001). In multivariable models, age and USG remained significant predictors of soiling. Higher soiling scores were associated with poorer performance on inhibitory control (P < .001) and detour tasks (P < .001).

Conclusions and clinical importance: Increased soiling behavior was linked to USG and executive function. Abnormal urinalysis findings were less frequent than expected. Soiling behavior in aging dogs might not exclusively reflect urinary tract or systemic disease and could be an indicator of cognitive decline.