Stability and Change in Type A Components and Cardiovascular Reactivity in Medical Students During Periods of Academic Stress¹

This study examined the effects of academic stress upon components of Type A behavior and cardiovascular reactivity. In a longitudinal design, heart rate and blood pressure responses to the Type A Structured Interview (SI) and additional laboratory challenges were measured in medical students at three points during an academic semester. Sessions 1 and 3 were scheduled during vacation periods; Session 2 took place during an intensive examination week. Results indicated that three “stylistic” components of Pattern A derived from the SI—loud and explosive speech, short response latency, and potential for hostility—increased significantly during the exam period. Similar increases achieved marginal significance for another stylistic component, rapid and accelerated speech. By contrast, global Type A assessments did not increase with academic demands. Cardiovascular reactivity was significantly but only moderately stable across the three sessions, showing less consistency than has been reported in previous research. In addition, there was little evidence in this study that cardiovascular reactivity was potentiated by academic stress or by Type A behavior. These results demonstrate the influence of naturalistic environmental factors on overt behavioral components that have recently been suggested as coronary risk factors. Therefore, it is advisable for future experimental and epidemiological research to examine the social and environmental context in which these behaviors occur.