Physiological (heart rate, blood pressure, electrodermal activity), biochemical (epinephrine, norepinephrine, cortisol) and subjective parameters (self-rating score) of 33 patients with panic disorder (diagnoses according to DSM-III-R) before, during and after stress exposure were compared with those of healthy controls. As stressors a video containing frightening scenes (FS), mental arithmetic (MA), a video documenting a patient suffering from a panic attack (PA) and an improvised speech (IS) were applied. We found significantly higher baseline levels of electrodermal activity (EDA) and norepinephrine (NE) secretion and a subsequent further increase during stress exposure in panic disorder patients as compared with normal controls. The most potent stressors during the trial proved to be mental arithmetics and improvised speech, which was evident in both groups. The situation panic attack video appeared to be a "panic disorder patient-specific" stressor; here we noticed the most pronounced reactions in the patient group. Panic disorder patients had significantly higher self-rating scores of the parameters panicky feelings, anxiety and nervousness at the beginning and throughout the investigation. We conclude that panic disorder patients have a higher degree of activation compared with normal controls, which is evident regarding levels of electrodermal activity and norepinephrine secretion. Furthermore, the panic attack video appears to be a panic disorder patient-specific stressor.
