Stress, hostility and depression increase the risk of stroke or transient ischemic attack in middle-aged and older adults, according to a University of Minnesota study.

For the study, researchers used data from another ongoing study on cardiovascular disease risk factors in six U.S. cities. The study included over 6,700 adults (38.5 percent of white, 27.8 percent African-American, 21.9 percent Hispanic and 11.8 percent Chinese) aged between 45-84 years. None of these participants had a history of cardiovascular diseases at the beginning of the study.

About 53 percent of the women also completed a questionnaire on chronic stress, depression, anger and hostility over a period of two years.

At the end of 8.5 to 11 years of follow up, 147 strokes and 48 TIAs were reported. The researchers found that 86 percent are more likely to suffer a stroke or TIA when depressed, 59 percent had heightened risk of developing a stroke and hostility doubles the risk of stroke or TIA. The researchers did not, however, discover any higher risk in case of anger.

"There's such a focus on traditional risk factors - cholesterol levels, blood pressure, smoking and so forth - and those are all very important, but studies like this one show that psychological characteristics are equally important," said lead author Susan Everson-Rose, Ph.D., M.P.H., in a statement.

"Given our aging population, it's important to consider these other factors that might play a role in disease risk. Stroke is a disease of the elderly predominantly, and so learning more about things that can influence risk for stroke as people age is important."

The finding is published in the American Heart Association journal Stroke.