Physiological reactivity and Type A behavior in preschool children: a longitudinal study.

Measurements of Type A behavior were related to cardiovascular (systolic and diastolic blood pressure, heart rate) and neuroendocrine (urinary catecholamines and cortisol) reactivity in 30 male and 30 female preschool children during various active conditions at their mean ages of 3.5, 4.5, 5.5, and 6.5. Significant elevations of physiological arousal occurred in most active conditions and for all physiological variables except cortisol. Playgroup leaders in daycare centers filled out a Swedish version of the scale measuring Type A behavior, and boys obtained significantly higher scores than girls. Whereas Type A scores were relatively consistent over time, however, physiological reactivity was not a stable individual characteristic, and correlations between Type A scores and cardiovascular reactivity reached significance in only 4 of 33 tests for the boys (one negative correlation) and in 1 case for the girls. Correlations between Type A scores and catecholamine reactivity did not reach significance. In summary, the data do not support the assumption of a consistent relationship between Type A behavior and physiological reactivity in preschool children. A significant correlation (r = .57, p less than .01) found for boys during a computer game suggests that an association may exist during "Type A-relevant" challenge.