Physical signs of canine cognitive dysfunction

Physical disturbances are common in dogs with canine cognitive dysfunction (CCD). However, the relation between these physical disturbances and CCD has not been clarified. The aim of this study was to clarify the physical disturbances in CCD by questionnaire survey. The questionnaire consisted of items of general information, physical disturbances (gait and posture abnormalities, and deteriorating perception) and a CCD assessment scale named the CCD rating scale (CCDR). The survey was conducted toward owners of dogs aged 10 years or older in two ways: A web-based (Web survey) and a paper-based (Paper survey) survey. To determine which physical disturbances were associated with CCD, ordinal logistic regression analyzes were performed. Through the Web survey, 726 valid responses were obtained, and the test results revealed that vision impairment, smell disturbance, tremor, swaying or falling and head ptosis were significantly associated with CCD. These items, except for head ptosis, were also significantly associated with, or tended to be associated with, CCD in 103 valid responses to the Paper survey. The prevalence of CCD was increased in the elderly dog population, especially in dogs aged 16 years or older. In contrast, physical signs gradually increased from 10 years of age. These results suggest that physical disturbances may appear in the early stages of CCD. In conclusion, the present study revealed new clinical signs of CCD linked to physical disturbances and suggested that these signs could be useful for detecting early stage of CCD.