Severe Stress May Cause Stroke
Patients who were rushed to a hospital suffering a stroke report that they had been experiencing severe stress for a long time prior to the stroke, according to a recent collaborative study conducted in Sweden. The patients in the study experienced a cerebral infarction, which is the type of stroke that occurs in about 85 percent of stroke cases.
Stroke is the third leading cause of death in the United State, according to the National Stroke Association. A stroke occurs when a blood clot blocks an artery that carries blood from the heart to the body or when a blood vessel breaks, interrupting blood flow to a region of the brain. Either of these events cause brain cells to die and damage to the brain. The American Heart Association lists many risk factors for stroke, including high blood pressure, high cholesterol, family history, diabetes, sedentary lifestyle, and smoking, but stress is not on the list.
Other research indicates a role of stress in causing disease. The body responds to stress by releasing stress hormones, and these hormones increase blood pressure, heart rate, and blood sugar levels. According to the National Cancer Institute, chronic stress can increase the risk of heart disease, depression, obesity, and other conditions. Studies also show that stress can affect the growth and spread of cancer, although the exact mechanisms involved are not yet understood.
In the Swedish study, the researchers asked nearly 600 patients to complete a questionnaire within 10 days after being admitted to the hospital with stroke (acute cerebral infarction). The patients were asked to choose from six options about how much stress they had experienced before their stroke, ranging from “never been stressed” to “constantly stressed over the past five years.” All of the responses were compared with those of healthy controls who responded to the same question.
The investigators found that the link between level of stress and the occurrence of stroke varied between different types of cerebral infarction. That is, they found an association between stress and stroke when the stroke is caused by atherosclerosis or blood clots that have developed locally in smaller vessels in the brain. They also noted a link among patients in whom a cause of the stroke had not been identified despite extensive evaluation.
The authors of the study note that although their results indicate a correlation between stress and stroke, the study depended on self-reporting, an approach that runs the risk of patients not remembering events correctly or of over-interpreting them. However, they regard their findings as important and as a strong indicator to further investigate the role stress plays in the development of stroke.
American Heart Association
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National Stroke Association
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