People who had strokes were more likely to have experienced anger or negative emotions in the two hours prior to the stroke than at the same time the day before the stroke.Try not to get angry. That’s the message gleaned from new Israeli research that found that anger appears to have a bigger effect on the onset of strokes than positive emotions. Anger and other negative emotions may be triggers for ischemic stroke, according to an Israeli study published in the December 14 issue of Neurology, the scientific journal of the American Academy of Neurology.

Strokes are the third leading cause of death in the United States and the leading cause of disability in adults. Each year, about 500,000 Americans suffer new strokes, and another 200,000 suffer a recurrent stroke. Thirty percent will die within the year, and another 30% will be unable to live independently. More than half of those who survive their strokes will die within eight years.

The study found that people who had strokes were more likely to have experienced anger or negative emotions in the two hours prior to the stroke than at the same time the day before the stroke. They were also more likely to have reacted quickly to a startling event, such as getting out of bed suddenly after hearing a grandchild fall down and cry or standing up from a chair quickly after hearing an unexpected loud noise. The people were also more likely to have experienced anger, negative emotions, or sudden changes in body position in the two hours before the stroke than they were, on average, in the year before the stroke.

The study’s lead researcher, Dr. Silvia Koton of the Israel Center for Disease Control, said many patients reported that stroke symptoms began after episodes of “overwhelming emotion.”

“There’s a lot of information and studies that have been done about the conventional reasons for the cause of strokes – high blood pressure, obesity, smoking – there are the main reasons, Koton told ISRAEL21c.”Despite that, there has been little research done to explain why a person has a stroke at a certain moment – what is the trigger that brings it on?”

The study examined 200 Israelis who were hospitalized with an ischemic stroke or a transient ischemic attack (mini-stroke). Ischemic stroke is caused by reduced blood flow to the brain. It is the most common type of stroke.

The study participants, who had an average age of 68, were interviewed one to four days after the stroke occurred. Approximately 30 percent of patients reported exposure to anger, negative emotions such as fear, irritability, or nervousness, or sudden changes in body position in response to a startling event during the two hours before the stroke. According to the study, exposure to a potential trigger could increase the risk of stroke by as much as 14 times during the two-hour period immediately following exposure.

Levels of anger and other negative emotions were rated on a scale. For example, participants were identified as exposed to anger if they said they had a peak level of anger at a five or higher on a seven-point scale, which was defined as “very angry,” “furious,” or “enraged.”

Researchers don’t know how these triggers precipitate a stroke. “It’s possible that brief episodes of mental stress cause transient changes in blood clotting and in the function of cells lining blood vessels. It is important to note that our study does not assess the cumulative risk related to exposures to potential triggers but short-term risks during the two-hour period immediately following exposures,” said Koton, who in addition to her research at the center for disease control also teaches at Tel Aviv University.

Sudden reactions to startling events could trigger stroke through effects on blood circulation or an excessive response by the sympathetic nervous system, which regulates body functions such as heart rate or blood pressure.

The study also examined whether other factors such as positive emotions, heavy physical exertion, and heavy meals were triggers for stroke, and no significant relationship was found.

Other studies have found that anger, negative emotions, sudden changes in body position, and heavy physical exertion may be potential triggers for heart attacks.

“The main modifiable risk factors for stroke are high blood pressure, smoking, diabetes, hyperlipidemia, and obesity. However, this study demonstrates that there are factors that may trigger the premature onset of stroke and this is an important area of potential intervention,” said Koton.

“We hope that the findings will lead to some prevention of strokes. One way is targeting groups of people who are prone to strokes because of one of the conventional reasons, and giving them training in behavior management – teaching them how to cope with anger and pressure. Behavior modification can protect their health to an extent,” she said. “The possibility of preventive medications to lessen the risk of stroke among specific high-risk groups might also be studied.”

Koton said further research might be able to identify the people most vulnerable to strokes set off by particular occurrences. “Although people cannot be told not to get mad, stress- and anger-coping programs can be offered to high-risk groups,” she said.

“There’s more work to be done – such as to explain why I act differently to a trigger than you do, but we’ve started the ball rolling by looking at the mechanism of the trigger.”

Kotin discounted the theory raised by some people who have read her study that Israelis might be more stroke-prone due to the various pressures they deal with on a daily basis.

“We’re all just people, and everyone reacts differently to pressure. What we’re talking about in the study is immediate anger and how that can trigger a stroke. And people around the world get angry, not just Israelis.”