Incidence and risk of coronary heart disease in an industrial population. A five-year prospective study.

In a large machinery factory a cohort of 3754 men aged between 40 and 50 years have been studied for 5 years. Total and coronary mortality rates have been determined and also the incidence of certain non-fatal states which required hospitalization due to various types of coronary heart disease (CHD), hypertension, brain apoplexy, diabetes mellitus and malignancies. Among the subjects exposed to CHD risk factors (RF), i.e. among smokers, hypertensive and hypercholesterolemic subjects, and among those who had a positive coronary family history and a positive cardiovascular (chest pain) questionnaire, both total and coronary mortality rates were several fold higher and they increased almost exponentially with increasing numbers of RF. Among the RF it was the cardiovascular (chest pain) questionnaire which had the highest prognostic value. Workmen manifested a higher total and coronary mortality than did the employees in the technico-economical professions (TEP). The highest mortality rate was found among the workmen employed in heavy manual occupation. In contrast the lowest total coronary mortality rate was observed in the TEP having little responsibility in their vocation and also among qualified workmen and specialized technical and scientifical workers.