Although uncontrolled anger and aggression are frequently associated with strokes, researchers now say the outbursts may be caused by brain damage itself rather than linked to episodes of stroke-related depression
"We think that the inability to control anger and aggression is more likely a symptom of brain injury rather than a reactive behavior secondary to stroke, even in patients with physical disabilities," says study author Jong S. Kim, MD of the Asan Medical Center in Seoul, Korea, in a news release.
Of the 145 stroke patients studied, 32% described an inability to control anger or aggression up to a year after their stroke. Sometimes the emotional eruptions occurred spontaneously and without provocation, and in other cases a family member may have prompted the unusual response.
Researchers also studied the number of lesions on the brains of the stroke patients. They found there was a link between the number and location of the lesions and the appearance of anger and aggression. The condition was also closely associated with speech and physical disabilities.
The study authors say their findings suggest that the inability to control anger or aggression should be included in the list of common behavioral problems caused by strokes -- along with depression and emotional instability.
The study is published in the April issue of Neurology.