The more symptoms of depression people have, the higher their risk of stroke, researchers say.
"There are a number of well-known risk factors for stroke, such as high blood pressure, diabetes and heart disease; but we are beginning to understand that there are nontraditional risk factors as well, and having depressive symptoms looms high on that list," said study co-author Virginia Howard. She's a professor in the School of Public Health at the University of Alabama (UA) at Birmingham.
"These nontraditional risk factors need to be in the conversation about stroke prevention," Howard said in a university news release.
The study included more than 9,500 Black people and more than 14,500 white people across the United States who were 45 and older and had no history of stroke.
A four-item depression scale was used to determine how often the participants felt depressed, sad or lonely or had crying spells.
During an average follow-up of nine years, there were more than 1,260 strokes among the participants.
Compared to participants with no depressive symptoms, those with scores of one to three had a 39% increased stroke risk. Those with scores of more than four had a 54% higher risk, after the researchers accounted for demographic factors.
Race didn't affect stroke risk, according to the study recently published in the journal Neurology: Clinical Practice.
One of the study's objectives was to determine whether depressive symptoms might help explain the increased risk that Black Americans have for stroke, especially in the South.
"The traditional risk factors don't explain all the difference in stroke risk between races," said study co-author Cassandra Ford, of the UA College of Nursing.
"The results have been mixed among the few studies that enrolled Black participants and examined race and depressive symptoms in relation to stroke. Depression often goes undetected and undiagnosed in Black patients, who are frequently less likely to receive effective care and management," Ford explained.
"These findings suggest that further research needs to be conducted to explore nontraditional risk factors for stroke," she concluded.