A new meta-analysis published in Circulation suggests having a dog may be associated with longer life and better cardiovascular outcomes, especially for stroke survivors who live alone. In a meta-analysis of 10 studies comprising over 3.8 million individuals, those who had dogs compared with those who did not significant reductions in all-cause mortality (24%), post heart attack mortality (65%), and other cardiovascular-related mortality (31%).
Of the 10 studies analyzed, 6 included comparison of all-cause mortality outcomes for dog owners vs nonowners, and 4 compared cardiovascular outcomes for dog owners vs nonowners. Individuals studied were age 40 to 85 and experienced heart attack or ischemic stroke between 2001 and 2012.
In a prospective registry study published in the same issue of Circulation, those who had dogs vs those who did not also had reduced mortality risk, which was modulated by whether they lived alone or with a child or partner. For those who lived alone after having a heart attack or stroke, the mortality risk reduction was 33% and 27%, respectively. Dog owners who lived with a partner or child had a 15% and 12% risk reduction compared with people without dogs.
The lower risk of death associated with dog ownership could be explained by an increase in physical activity and decreased depression and loneliness, both of which have been connected to dog ownership in previous studies.
“We know that social isolation is a strong risk factor for worse health outcomes and premature death,” said Tove Fall, DVM, professor at Uppsala University and coauthor on the prospective registry study. “Previous studies have indicated that dog owners experience less social isolation and have more interaction with other people. Furthermore, keeping a dog is a good motivation for physical activity, which is an important factor in rehabilitation and mental health. The results of this study suggest positive effects of dog ownership for patients who have experienced a heart attack or stroke. However, more research is needed to confirm a causal relationship and giving recommendations about prescribing dogs for prevention.”
Jeffrey D. Kennedy, MD; and Melissa J. Chen, MD, MPH
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