In 1978, available prospective and retrospective research provided a data base that lead to the establishment of the Type A behavior pattern (TABP) as a risk factor for CHD. Since then a growing body of more recent research has now called into serious question the robustness of the association between global TABP and CHD. The most damaging evidence has been the negative findings of the well-controlled prospective study of TABP in MRFIT, followed by recent repeated failures to link TABP to angiographically documented coronary artery disease. However, the method of component scoring of the Structured Interview (SI) has demonstrated that some components of the multidimensional TABP have consistent association with CHD, even when global TABP shows no relationship.
The aim of the proposed research is to component score SI's derived from the two major prospective studies of TABP -- WCGS and MRFIT -- in an attempt to identify specific components of TABP that are consistently related to the incidence of CHD. If the same attributes that are related to angiographic findings are also predictive of incidence of CHD in both of these prospective studies, then their status as coronary-prone behaviors will be well established. Such data also would help clarify the reasons for the inconsistent epidemiological findings reported for TABP in WCGS and MRFIT, and to direct research resources in a more profitable direction. In this connection, an additional aim of the proposed research is to examine whether the same components of tABP that are related to CHD are also related to exaggerated challenge-induced cardiovascular reactivity in over 1,000 subjects derived from nine psychophysiological studies, of which a subset included ambulatory monitoring of cardiovascular response during daily activity.
A final aim of the proposed research is to determine how specific pathologic components of the TABP and other behavioral characteristics interact to affect cardiovascular reactivity both in the laboratory and in daily life during (a) cigarette smoking alone (b) stress alone and (c) cigarette smoking while engaged in stressful activity. Findings may permit identification of smokers who are particularly at risk for CHD and to suggest pathways whereby behavioral dispositions, stressful experience, and cardiovascular reactions interact to heighten cigarette smoking as a risk factor for CHD.
