Psychological Factors and Heart Disease
A number of studies have revealed that perceived emotional stress can produce various transient cardiovascular responses. The reactions may include changes in heart rate and cardiac output. They may include abnormalities in heart rhythm, changes in blood pressure, peripheral resistance, blood viscosity, blood clotting time, and serum cholesterol levels. A hypothesis suggested by the findings which requires further research follows: If these cardiovascular responses were sustained for a period of time, they would ultimately influence the onset or course of coronary artery disease. These studies also suggest that emotional tension at one's work may place an additional strain on an already diseased heart.In patients whose cardiovascular system is already impaired, investigators have traced the sequence from emotional upset to heart disease. Since the reported evidence has been based on cardiac subjects, it is still possible that "gradual increase in tension" is perceived only after illness occurs, but not necessarily perceived as stressful before beart disease. Owing to the lack of prospective studies in which the life stress factors are studied prior to heart disease, emotion as a cause or contributory factor to heart disease has not been fully accepted. These studies suggest that certain personality traits may be common to certain forms of heart disease. Most of this evidence has been observed from time-consuming, detailed personality analysis, and the evidence depends on studies of relatively few patients and poor or no controls.It is important to note that these studies on personality type and heart disease were conducted after heart disorders developed. This raises the question of whether the reported personality characteristics preceded or followed the heart disease. The investigations to date assume that the personality structure occurred before the appearance of the heart disease, but before we can answer this question, a longitudinal study of the personality of individuals prior to cardiovascular disease would be necessary.