Does Dog Ownership Impact Older Adult Physical Activity, Brain And Cognitive Health?

Physical activity and social interactions resulting from dog ownership and dog walking may benefit older adults’ brain health and reduce dementia risk. However, the relationship between pet ownership and brain-level indicators of dementia risk in older adults, including brain structure and function, remains unknown. PURPOSES: The purposes of this study were to pilot methods for examining behavioral risk factors (physical activity and social interaction) for dementia, as well as to determine differences in cognitive function and brain health (structure and function) in older adult dog owners compared to non-dog owners. METHODS: Older adult participants (n = 25; age 75[4] years; 60% female) completed two study visits, consisting of the National Institute of Health (NIH) Toolkit Cognitive Battery and a 45-minute MRI brain scan that included structural brain imaging. The primary cognitive outcome was the fluid composite score from the NIH Toolkit. Participants also wore an activPAL physical activity monitor (24 hrs/d) and logged all dog walking for 7 days. RESULTS: Non-dog-owner and dog-owner mean(SD) step counts were 7106.8(2989.5) steps/day and 8972.2(5650.3) steps/day, respectively. Dog owners took an average of 1865 steps/day more than non-dog-owners. 10/11 dog walkers reported having gotten to know people in their neighborhood as a result of their dog. Of those, 9/10 said they regarded someone they had met through their dog as a friend, and 9/10 received one or more types of social support through someone they had met through their dog. The fluid cognition composite scores for dog owners and non-dog owners were 55.6(8.8) and 58.0(7.1), respectively. There were no group differences in gray matter volume, white matter volume, left or right hippocampal volume, and left or right cortical thickness, when controlling for age, sex, education and total intracranial volume. CONCLUSIONS: This pilot study demonstrated the feasibility of these study methods, and will inform a larger, fully-powered study. If our hypotheses are supported, this research could inform dementia prevention programs and policies that leverage the human-dog bond, such as supporting dog ownership in older adulthood or developing behavioral and environmental programs that support dog walking.