According to a unique patient study extended stress has been found to cause stroke, also called cerebral infarction.
Conducted by research collaborators from the Sahlgrenska Academy at the University of Gothenburg and Sahlgrenska University Hospital, Sweden, the study found that many stroke patients urgently admitted to hospital have stated that they were under great stress over a prolonged period prior to suffering their stroke.
"There appears to be a correlation between stress and stroke, but this needs to be interpreted with great caution. We asked about self-perceived stress among the stroke patients, and there is, of course, a risk of patients who have just had a cerebral infarction remembering incorrectly or over-interpreting with regard to their level of stress," said Katarina Jood, a researcher at the Sahlgrenska Academy.
For the study, nearly 600 patients were asked to complete a questionnaire, ten days after being admitted to Sahlgrenska University Hospital with acute cerebral infarction.
In the questionnaire, the patients were asked to choose between six different alternatives to indicate how stressed they had felt before their stroke, from "never been stressed" to "constantly stressed over the past five years".
The patients' responses were compared with a healthy control group who were asked the same question.
"We found an independent link between self-perceived psychological stress and stroke. A new finding was that the link between stress and stroke varies between different types of cerebral infarction," said Jood.
The study found that there is a link to stress in those cases where the stroke is caused by atherosclerosis or to blood clots that have developed locally in the smaller vessels of the brain.
The link was also found for those patients in whom it had not been possible to establish the cause of the stroke despite an extensive evaluation.
On the contrary, the researchers could not see any independent correlation with stress for those patients who had had a stroke due to a blood clot from the heart.
"We do not know why stress appears to play a greater role in particular types of stroke, but it is an important finding as it prompts further studies on what role stress plays in the development of stroke," said Jood.
The study has been published in the scientific journal BMC Medicine.