A new study by the US National Institute on ageing has warned that ambitious and aggressive people are at a risk of heart attacks and strokes as compared to agreeable and more trusting people. The research was carried out in four villages of Italy and subjects were closely observed for a period of three years. The study directly relates tension and stiffness in neck arteries to stress caused by anger and aggression. The conclusion was reached with a help of personality test taken by respondents which measures antagonism.