Researchers at Columbia University have found that clinically depressed women are more than twice as likely to die after a heart attack than happy women. The findings of the study have been published in the Journal of the American College of Cardiology, and involved more than 63,000 women. According to the findings, the more depressed a woman is the greater the chance of a sudden cardiac death, and researchers suggested this could be because unhappy women are more likely to smoke, have high blood pressure and eat badly. The risk was even higher among women on antidepressant drugs. Although, researchers say this could be because antidepressants are given to the most depressed women–they would like to conduct more studies to explore a possible link between them and sudden cardiac death.