Psychological investigations carried out on 1326 Helsinki policemen showed that individuals with electrocardiogram (ECG) signs of coronary heart disease (CHD), and those showing symptoms, were more anxious, aggressive, defensive and inhibited than those free from signs or symptoms. It is suggested that the poor prognosis associated with angina pectoris may be related to the psychological characteristics of the patients who suffer from it. Studies of 5- and 10-year prospective data showed that subjects dying from myocardial infarction differed from survivors on six significant psychological characteristics, including optimism, inhibition and superego strength. Multiple logistic analysis showed an association of lowered self-esteem and high somatization with myocardial infarction. A particular statistical analysis ("ridit analysis") revealed the existence of 4 variables (inhibition, neuroticism, differentiation and certainty) which distinguished to some degree with different manifestations of CHD. The nature of these variables and the correlations involved are discussed. It is concluded that psychological variables have some predictive power not only for the risk of CHD, but also for the risk of clinically different CHD events.