RELATIONSHIP BETWEEN JOB STRESS AND PLASMA FIBRINOLYTIC-ACTIVITY IN MALE JAPANESE WORKERS

Psychosocial job stress has been shown to be associated with the devel opment of cardiovascular disease. However, the pathophysiological mech anisms underlying this relationship remain unclear. The aim of the pre sent study was to elucidate whether marked job stress affects the para meters of blood coagulation and fibrinolysis, such as plasma fibrinoge n concentration, tissue plasminogen activator (t-PA), and plasminogen activator inhibitor 1 (PAI-1) activities, in 213 middle-aged male work ers in a computer-producing factory. Job stress was measured using a J apanese version of the Job Content Questionnaire (JCQ) developed by Ka rasek. The mean t-PA activity in workers with lower and higher job dem ands was 0.23 and 0.18 IU/ml respectively, and this difference was sig nificant (P < 0.05). The mean plasma fibrinogen in workers with lower and higher job decision latitude was 224.8 and 236.3 mg/dl respectivel y, and the mean PAI-1 activity in workers with lower and higher job st rain was 14.9 and 17.7 U/ml respectively, though these differences rem ained at a borderline level of significance (0.05 < P < 0.10). Multipl e regression analyses showed that the parameters of blood coagulation and fibrinolysis were closely associated with the cardiovascular risk factors of age, obesity, blood pressure, elevated serum lipids, and sm oking, but that high job demands were significantly related to decreas es in t-PA activity, independently of the traditional risk factors. Th ese results suggest that psychosocial job stress may be related, at le ast partly, to the development of cardiovascular disease via changes i n plasma fibrinolytic activity.