Study shows long-term pet ownership linked to slower decline in cognition over time
American Academy of Neurology
"Prior
studies have suggested that the human-animal bond may have health benefits like
decreasing blood pressure and stress," said study author Tiffany Braley,
MD, MS, of the University of Michigan Medical Center in Ann Arbor and a member
of the American Academy of Neurology. "Our results suggest pet ownership
may also be protective against cognitive decline."
The
study looked at cognitive data from 1,369 older adults with an average age of
65 who had normal cognitive skills at the start of the study. A total of 53%
owned pets, and 32% were long-term pet owners, defined as those who owned pets
for five years or more. Of study participants, 88% were white, 7% were Black,
2% were Hispanic and 3% were of another ethnicity or race.
Researchers used data from the Health and Retirement Study, a large study of Medicare beneficiaries. In that study, people were given multiple cognitive tests. Researchers used those cognitive tests to develop a composite cognitive score for each person, ranging from zero to 27. The composite score included common tests of subtraction, numeric counting and word recall. Researchers then used participants' composite cognitive scores and estimated the associations between years of pet ownership and cognitive function.
Over
six years, cognitive scores decreased at a slower rate in pet owners. This difference
was strongest among long-term pet owners. Taking into account other factors
known to affect cognitive function, the study showed that long-term pet owners,
on average, had a cognitive composite score that was 1.2 points higher at six
years compared to non-pet owners. The researchers also found that the cognitive
benefits associated with longer pet ownership were stronger for Black adults,
college-educated adults and men. Braley says more research is needed to further
explore the possible reasons for these associations.
"As
stress can negatively affect cognitive function, the potential stress-buffering
effects of pet ownership could provide a plausible reason for our
findings," said Braley. "A companion animal can also increase
physical activity, which could benefit cognitive health. That said, more
research is needed to confirm our results and identify underlying mechanisms
for this association."
A
limitation of the study was that length of pet ownership was assessed only at
one time point, so information regarding ongoing pet ownership was unavailable.
The
study will be presented at the American Academy of Neurology's 74th Annual
Meeting being held in person in Seattle, April 2 to 7, 2022 and virtually,
April 24 to 26, 2022.
The
study was supported by the National Institutes of Health, the National Heart,
Lung, and Blood Institute and the National Institute on Aging.
