In a new Swedish study investigating the association between dog ownership and cardiovascular health, researchers found that dog owners have a reduced risk of death due to cardiovascular disease and other causes.
The protective link is particularly strong among people who live alone and among those who own dog breeds originally bred for hunting.
For the study, the research team from Uppsala University analyzed the data of more than 3.4 million Swedes aged 40 to 80 with no history of cardiovascular disease and compared the information to seven different national data sources, including two dog ownership registries.
“A very interesting finding in our study was that dog ownership was especially prominent as a protective factor in persons living alone, which is a group reported previously to be at higher risk of cardiovascular disease and death than those living in a multi-person household,” said Mwenya Mubanga, lead junior author of the study and Ph.D. student at the Department of Medical Sciences and the Science for Life Laboratory, Uppsala University.
“Perhaps a dog may stand in as an important family member in the single households. The results showed that single dog owners had a 33 percent reduction in risk of death and 11 percent reduction in risk of myocardial infarction during follow-up compared to single non-owners. Another interesting finding was that owners to dogs from breed groups originally bred for hunting were most protected.”
In Sweden, each resident is given a unique personal identity number. Every visit to a hospital is recorded in national databases, accessible to researchers after de-identification of data.
Even dog ownership registration has been mandatory in Sweden since 2001. This allowed scientists to study how being registered as a dog-owner relates to a later diagnosis of cardiovascular disease or death from any cause.
“These kind of epidemiological studies look for associations in large populations but do not provide answers on whether and how dogs could protect from cardiovascular disease,” said Dr. Tove Fall, senior author of the study and associate professor in epidemiology at the Department of Medical Sciences and the Science for Life Laboratory, Uppsala University.
“We know that dog owners in general have a higher level of physical activity, which could be one explanation to the observed results. Other explanations include an increased well-being and social contacts or effects of the dog on the bacterial microbiome in the owner.”
“There might also be differences between owners and non-owners already before buying a dog, which could have influenced our results, such as those people choosing to get a dog tending to be more active and of better health,” said Fall.
“Thanks to the population-based design, our results are generalizable to the Swedish population, and probably also to other European populations with similar culture regarding dog ownership.”
Their findings are published in the journal Scientific Reports.
Source: Uppsala University