Adults older than 50 who have long-term depression symptoms have double the risk of stroke as adults who don’t show signs of the mood disorder, new research shows.
And the increased stroke risk remains, even after the depression symptoms ease, especially for women, say researchers led by Paola Gilsanz, a postdoctoral research fellow at Harvard University’s T.H. Chan School for Public Health in Boston.
“This is the first study evaluating how changes in depressive symptoms predict changes in stroke risk,” Gilsanz said in a university news release. “If replicated, these findings suggest that clinicians should seek to identify and treat depressive symptoms as close to onset as possible, before harmful effects on stroke risk start to accumulate.”
The findings were published online May 13 in the Journal of the American Heart Association.
Tracking mood and stroke history
Researchers followed more than 17,000 men and women ages 50 and older who were participating in the Health and Retirement Study from 1998 to 2010. Participants were interviewed every two years about a wide range of health indicators, including depression, stroke risk factors and stroke history.
Researchers found people who showed elevated depression symptoms in two consecutive interviews were more than twice as likely to suffer a first stroke as those who showed lower depression levels.
Stroke risk remained high even among people whose depression symptoms eased between interviews, especially among women. And, researchers found, people who developed depression symptoms between interviews didn’t have the elevated stroke risk.
People younger than 65 had greater stroke risk associated with depression symptoms than older people.
Why does mood make a difference?
It’s possible depression itself causes some sort of change in blood vessels that increases the risk of stroke, researchers suggested. It’s also possible lifestyle behaviors seen in depressed people ““ lack of physical activity or higher incidence of smoking ““ may play a role.
More research is needed to determine whether the results can be duplicated in other groups, or across larger sections of the population, said study senior author Maria Glymour, an epidemiologist at the University of California, San Francisco.
The Health and Retirement Study is funded by the National Institute on Aging and conducted by the University of Michigan.
