People who have suffered a heart attack may be at an increased risk for suicide, according to a new Danish study.

Heart attack patients without a history of previous mental illness were at least three times more likely to commit suicide in the month following their hospital discharge than those in the general population who had not had a heart attack, the researchers said.

However, among heart attack patients who did have a psychiatric disorder, their suicide risk was substantially greater.

Heart attacks are known to be stressful events, and they put people at risk for depression , anxiety and poor quality of life. The new study supports the American Heart Association's recommendations to screen heart attack patients for depression and suicidal thoughts , the researchers said.

Additionally, the study provides another reason to continue to test the effects of depression treatments on heart attack patients. Not only might those treatments whether they're medications or behavioral therapies help reduce the risk of death from cardiovascular events, but they also may reduce the risk of patient suicide, Dr. Redford B. Williams, a professor of psychology and neuroscience at Duke University in Durham, N. C., wrote in an editorial accompanying the study. A recent study found those people with both heart disease and depression were five times more likely to die than healthy people over a five-year period.

Although previous studies have found that chronic conditions, including stroke, are associated with an increase in suicidal plans, the new study is the first to look specifically at the link between heart attack and suicide.

Researchers from Aarhus University and the University of Southern Denmark examined data from five of the country's national registries of health information. They found more than 19,800 people ages 40 to 89 who had committed suicide between 1981 and 2006. For each suicide case, they identified up to 10 people in the registry of a similar age who had not committed suicide , a total of more than 190,000 control subjects.

Of those who had committed suicide, 4.3 percent had suffered a heart attack, compared with 2.9 percent of the control group.

Special attention should be paid to heart attack patients who already suffer from psychiatric illness, as this group was at very high risk of suicide, the researchers said.

The study was published online Nov. 22 in the journal Circulation.

Pass it on: Heart attack patients may be at an increased risk for suicide, particularly in the month following the event.

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