July 10, 2014 | Steven Reinberg
The study found that depression seemed to raise the risk of a stroke or a transient ischemic attack (TIA) by 86 percent. It also found that stress apparently raised stroke or TIA risk by 59 percent. And hostility doubled the risk, the researchers said. A TIA is a mini-stroke caused by a temporary blockage of blood flow to the brain. However, it's important to note that the study only found an association between the risk of stroke and negative emotions. It wasn't designed to prove that negative emotions can cause strokes.
Still, "chronic stress and negative emotions are important psychological factors that affect one's health, and findings from this study link these factors to brain health in particular," said the study's lead author, Susan Everson-Rose, an associate professor of medicine at the University of Minnesota.
"Patients and their health care providers should be aware that experiences of chronic stress and negative emotional states can increase risk for stroke," she noted. The findings were published online July 10 in the journal Stroke.
For the study, Everson-Rose and her colleagues collected data on nearly 7,000 adults, aged 45 to 84, who took part in the Multi-Ethnic Study of Atherosclerosis. The study included people from six different sites in the United States.
Participants filled out questionnaires asking about chronic stress, depressive symptoms, anger and hostility. None of the patients had heart disease or a history of stroke at the beginning of the study.
After an average follow-up of about 8.5 years, just under 3 percent of the original group had suffered either a stroke or a mini-stroke -- 147 participants had a stroke and 48 had a mini-stroke, according to the study.
The researchers found that those who reported the highest levels of emotional problems were at the greatest risk for a stroke or mini-stroke, compared with those with the lowest levels of stress, hostility and depression. These associations remained significant even when the researchers took into account age, race, sex, health behaviors and other known risk factors for stroke, Everson-Rose and colleagues noted. Interestingly, anger didn't appear to significantly increase the risk for stroke or mini-stroke, the investigators found.
The researchers didn't ask about people's coping strategies. So they don't know if how people coped with their emotions could have had an effect on stroke risk.
For those concerned about reducing their stroke risk, classic risk factors -- such as smoking and high blood pressure -- are important. But, this study suggests that people also need to pay attention to stress and emotions and how they affect health, Everson-Rose said.
Dr. Richard Libman, chief of vascular neurology at North Shore-LIJ Health System in Manhasset, N.Y., said, "Psychological factors have been long thought to play a role in heart disease and stroke." Depression isn't just a consequence of stroke, but predicts a higher risk of stroke years in advance, he said.
"Chronic stress has been thought to be a risk factor for stroke. In other studies, acute stress has also been found to be a trigger for stroke, that is to say that strokes occur immediately after a stressful event more often than would be expected," Libman explained. "This study reopens a neglected field in stroke research, that is the psychological aspects of our lives, which can have a profound impact on our health," he said.
Dr. Jeffrey Borenstein, president and CEO of the Brain & Behavior Research Foundation in New York City, said that for overall health, it's important that people suffering stress and depression get professional help. "People shouldn't suffer in silence, they should seek help, whether it be talk therapy, medication or a combination of the two," he said.