Personality traits of aged dogs according to their cognitive status

Canine cognitive dysfunction (CCD) syndrome is a neurodegenerative condition that shares similarities with Alzheimer’s disease (AD) in humans. In human studies, high neuroticism, low openness, and low extraversion have been significantly associated with AD diagnosis. Similarly, changes in dog behaviour, including alterations in personality, have been reported as common features in dogs with CCD, but no precise assessment of their changes has yet been realised. The aim of this study (based on the CaniAge cohort) was to compare characteristics of dogs with cognitive impairment (CI dogs) and non-CI dogs in a French senior dog population including owner-reported personality traits between dogs. Data were collected via an online survey, including the CADES scale (Canine Dementia Scale), the Monash Canine Personality Questionnaire, the Canine Owner-Reported Quality of Life (CORQ) assessment, and an environment questionnaire. Dogs aged of 6 years and older were included. Responses were obtained for 566 senior dogs of various breeds, with a median age of 9.86 years (Interquartile range: 8.08–11.98). Among them, 234 were classified as cognitively impaired, including 182 with mild impairment, 44 with moderate impairment, and 8 with severe impairment or dementia. Compared to non-CI dogs, CI dogs scored significantly lower on extraversion and amicability, and higher on neuroticism. After adjustment, CI dogs showed significantly lower amicability and higher neuroticism compared to non-CI dogs. This study is complementary of previous studies regarding CI-characteristics but is also the first to explore personality trait differences between CI and non-CI dogs, supporting observations previously reported in Alzheimer's disease research. • Dogs with cognitive impairment (CI) differ in personality profiles. • Neuroticism is higher in dogs with CI after adjustment. • Amicability is lower in dogs with CI after adjustment. • Dogs with CI have a lower quality of life than dogs without CI.