The first analysis of data from the Kardiozive Brno 2030 study examines the association of pet ownership -- specifically dog ownership -- with cardiovascular disease risk factors and cardiovascular health.

It finds that owning a pet may help maintain a healthy heart, especially if that pet is a dog.

The study first established baseline health and socio-economic information on more than 2,000 subjects in the city of Brno, Czech Republic, from January 2013 through Dec. 2014, follow up are schedule every five years until 2030. In the 2019 evaluation, the study looked at 1,769 subjects with no history of heart disease and scored them based on Life's Simple 7 ideal health behaviors and factors, as outlined by the American Heart Association: body mass index, diet, physical activity, smoking status, blood pressure, blood glucose and total cholesterol.

They compared the cardiovascular health scores of pet owners overall to those who did not own pets, and dog owners to other pet owners and those who did not own pets. 

Pet owners were more likely to report higher physical activity, better diet and a healthier blood sugar range, but independent of their age, sex and education level dog owners were the healthiest.

The study is a statistical correlation, so obviously only exploratory the way a study in mice or in cells is. As with mouse studies, anyone who claims effects are causal in humans is selling you something, in this case a pet. Just as having a baby won't save your marriage, deciding to adopt, rescue or purchase a pet as a potential strategy to improve cardiovascular health is suspect. It could instead be that healthier people choose pets that are more active while people who are obese choose cats. 

Still, Francisco Lopez-Jimenez, M.D., chair of the Division of Preventive Cardiology at Mayo Clinic in Rochester, says that having a dog may prompt owners to go out, move around and play with their dog regularly. Owning a dog also has been linked to better mental health in other studies and less perception of social isolation -- both risk factors for heart attacks. Dr. Lopez-Jimenez is a senior investigator of this study.