Vital exhaustion, temperament, and cardiac reactivity in task-induced stress.

The associations between vital exhaustion (long-term stress), temperament, and cardiac reactivity were studied during an experimentally induced stress in a sample of 76 healthy subjects. Vital exhaustion was assessed with the Maastricht Questionnaire(MQ), and temperament with Cloninger's Temperament and Character Inventory (TCI). Cardiac reactivity was measured in terms of heart rate, respiratory sinus arrhythmia, and pre-ejection period. They were continuously measured during three stressors, i.e. mental arithmetic, reaction time, and giving speech. Results showed that vital exhaustion (long-term stress) was first of all associated with parasympathetic withdrawal. In addition, among exhausted persons the initial parasympathetic tone had no effect on task-induced parasympathetic reactivity, whereas in non-exhausted subjects parasympathetic reactivity was greatest when initial parasympathetic tone was high. Vital exhaustion interacted with temperament and gender: exhausted, persistent women expressed the highest level of physiological stress reactivity. Findings suggest that background stress may diminish one's capacity to cope with acute stress.