title: Prevalence of behavioral changes associated with age-related cognitive impairment in dogs.
abstract: OBJECTIVE
  To determine the prevalence of age-related behavioral changes, namely impairment, in a randomly chosen population of dogs.
  
  
  METHODS
  Age-stratified cohort study.
  
  
  METHODS
  97 spayed female and 83 castrated male dogs that were 11 to 16 years old.
  
  
  METHODS
  Data on possible impairment in 4 behavioral categories (ie, orientation in the home and yard, social interaction, house training, and sleep-wake cycle) linked to cognitive dysfunction were obtained from dog owners, using a structured telephone interview. Hospital records of dogs had been screened to exclude dogs with dysfunction in organ systems that may cause behavioral changes. Dogs with behavioral impairment were those with > or = 2 signs of dysfunction within a category. Dogs with impairment in 1 category were considered mildly impaired and those with impairment in > or =2 categories were considered severely impaired.
  
  
  RESULTS
  Age by sex interactions for dogs with impairment in any category were not significant, and, therefore, data on castrated males and spayed females were pooled for analyses across ages. The prevalence of age-related progressive impairment was significant in all categories. The percentage of 11- to 12-year-old dogs with impairment in > or = 1 category was 28% (22/80), of which 10% (8/80) had impairment in > or = 2 behavioral categories. Of 15- to 16-year-old dogs, 68% (23/34) had impairment in > or =1 category, of which 35% (12/34) had impairments in > or = 2 categories. There were no significant effects of body weight on the prevalence of signs of dysfunction in the behavioral categories.
  
  
  CONCLUSIONS
  Data collected provide estimates of the prevalence of various degrees of age-related behavioral changes associated with cognitive dysfunction in dogs. Age-related behavioral changes may be useful indicators for medical intervention for dogs with signs of cognitive impairment.
authors.affiliation: Animal Behavior Clinic, Portland, OR 97202, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Neilson
authors.forename: B L
authors.initials: BL
authors.lastname: Hart
authors.forename: K D
authors.initials: KD
authors.lastname: Cliff
authors.forename: W W
authors.initials: WW
authors.lastname: Ruehl
mesh_terms: D000367:Age Factors; D000818:Animals; D001522:Behavior, Animal; D003072:Cognition Disorders / Q000453:epidemiology*; D015331:Cohort Studies; D003221:Confusion; D003430:Cross-Sectional Studies; D004283:Dog Diseases / Q000453:epidemiology*; D004285:Dogs; D005260:Female; D006311:Hearing Disorders / Q000453:epidemiology / Q000662:veterinary; D008297:Male; D015995:Prevalence; D014786:Vision Disorders / Q000453:epidemiology / Q000662:veterinary