The effects of psychosocial and clinical factors on mortality in ischemic heart disease (IHD) were examined in a 10-year follow-up of 150 middle-aged men. Three groups of men were included: men with clinically manifest IHD, men with risk factors and healthy men. Psychosocial factors were assessed by means of standardized questionnaires. They comprised educational level, social class, marital status and a comprehensive assessment of the daily rounds of life of these men. Furthermore, a subjective rating of the own general health status was obtained. The clinical investigation included a standard physical examination, fasting serum lipids, glucose and urate, a frontal and sagittal chest X-ray and a 24-hour ambulatory ECG monitoring. During follow-up 37 men died, 20 of them from IHD. Non-survivors were discriminated from survivors by the following factors: older age, lower education, lower social class, higher systolic blood pressure, increased ventricular irritability and cardiac enlargement. Furthermore, a relative social isolation as indicated by a low social activity level and a poor self-rated general health status was characteristic of non-survivors. In multivariate analyses three factors emerged as the equally strong predictors of mortality, both from all causes and from IHD: social isolation, a poor self-rated health status and ventricular irritability. The psychosocial mortality predictors were independent of and of similar strength as the clinical predictors.