The relationship of physiological responses to the coronary-prone behavior pattern in children.

Forty-one male and female children were tested for Type A (coronary-prone) behavior using the Bortner test and the MYTH questionnaire. Based on their classification as A or B, three physiological variables were compared: systolic blood pressure (SBP), heart rate (HR) (phasic, tonic, and variability), and skin conductance (SC) (magnitude and latency of responses, number of spontaneous responses) during a 3-min rest period, a 10-min unsignaled reaction time (RT), and a 10-min word task. When using the Bortner to classify groups, Type As showed a tendency toward higher SBP levels and greater SBP reactivity to tasks, and significantly greater HR levels, HR reactivity to tasks, HR variability during rest, and SCR magnitude to RT signals. When using the MYTH, Type A females showed larger increases in SBP and HR to tasks, a lower mean HR, and a faster RT. Type A males showed a higher mean HR. Thus, children classified as Type A resemble Type A adults when compared on physiological responses to stress; however, the results depend on the method used to determine Type A behavior.