The study points to dog ownership enhancing the effects of other protective lifestyle measures like not socially isolating and exercising regularly.

Current dog owners (8.6 %) had an odds ratio (OR) of 0.60 (95 %CI: 0.37-0.977) of having disabling dementia compared to past and never owners. For cat ownership, the corresponding OR was 0.98 (95 %CI: 0.62-1.55). Current dog owners with a regular exercise habit had an OR of 0.37 (0.20-0.68) compared to past and never dog owners with no exercise habit. Further, current dog owners with no social isolation had an OR of 0.41 (0.23-0.73) compared to past and never dog owners with social isolation. Dog ownership had a suppressive effect on incident disabling dementia after adjusting for background factors over a 4-year follow-up period. Specifically, dog owners with an exercise habit and no social isolation had a significantly lower risk of disabling dementia.