Type A behavior and coronary atherosclerosis.

OBJECTIVES: To evaluate whether the pathogenesis of type A behavior may involve the premature development of coronary atherosclerosis. BACKGROUND: Type A or coronary-prone behavior is considered a possible risk factor for the development of coronary heart disease. Premature development of coronary atherosclerosis is suspected to play a role. Utilizing electron beam computed tomography, one can accurately determine the degree of coronary artery calcification, which is reflective of coronary atherosclerosis. METHODS: We performed a study of 35 men who had no clinical evidence of coronary heart disease. Twenty exhibited severe type A behavior and 15 exhibited type B behavior. All subjects were given an Electron Beam Computed Tomography scan of their coronary arteries and a treadmill electrocardiogram. RESULTS: Eight of the 20 (40%) type A subjects were found to have coronary calcification compared to none of the type B subjects (P=0.005). The correlation coefficient between type A score and coronary calcium score was 0.39 (P=0.09). CONCLUSIONS: The pathophysiology by which type A behavior increases the risk for coronary heart disease may involve the premature development of coronary atherosclerosis.

Effect of type A behavioral counseling on frequency of episodes of silent myocardial ischemia in coronary patients.

Thirteen of 32 patients with coronary heart disease who also exhibited symptoms and signs of severe time urgency and hostility (the two overt components of type A behavior [TAB]) were found to exhibit multiple episodes of silent myocardial ischemia over a 48-hour period of Holter monitoring as indicated by electrocardiogram ST depressions. Ten of these 13 patients were given 14 months of TAB counseling in an attempt to diminish the intensity of their time urgency and hostility. The remaining three patients served as controls. After counseling, the intensity of the time urgency and hostility of the 10 counseled patients diminished 53% and 59%, respectively, as measured by the videotaped clinical examination. The time urgency and hostility of the three uncounseled control patients did not significantly change. The mean frequency of ischemic episodes in the 10 patients who received TAB counseling significantly declined from an initial 6.6 to 3.1 ischemic episodes per 24 hours. However, the mean frequency of ischemic episodes did not significantly decline in 2 of the 3 uncounseled patients. The third uncounseled patient developed a conduction defect in the 14-month interlude, making an analysis of his repeat 48-hour electrocardiogram for episodes of ST depression impossible.