Type A behaviour, education and psychosocial work characteristics in relation to ischemic heart disease--a case control study of young survivors of myocardial infarction.

The interaction of Type A behaviour, psychosocial work environment and education in relation to medical risk factors for IHD was analyzed in a case-control study of male and female post-MI-patients under age 45. In multivariate analysis LDL/HDL-cholesterol ratio and smoking (explaining 27 and 6% of the variance) emerged as the two most important discriminators of patients from control subjects. The third factor, variety of work tasks, explained 5% of the variance. Type A behaviour ranked as factor no. 7, explaining only 2% of the variance and educational level did not reach statistical significance as an independent explanatory factor. When the sample was divided into men and women with high and low education, most of the patient-control difference in Type A and psychosocial work characteristics was found among highly educated men on one hand and women with a low level of education on the other. Thus Type A behaviour seems to be less important and psychosocial work environment more important in adding psychosocial risk to the medically established risk of IHD.