Basal sympathoadrenal function in posttraumatic distress disorder.

Research has consistently shown that patients with posttraumatic stress disorder (PTSD) manifest greater changes in heart rate, blood pressure, and plasma epinephrine than controls when exposed to trauma-related laboratory stressors. However, findings are equivocal as to whether PTSD subjects differ from controls on basal, or tonic, measures of autonomic activity. In this study, PTSD patients (n = 11) and asymptomatic controls (n = 11) were compared on measures of basal sympathoadrenal function, including plasma norepinephrine and epinephrine as well as heart rate and blood pressure. Results showed that PTSD patients were not significantly different from control subjects on any measure. Although phasic alterations in autonomic function in PTSD have been consistently found in previous research, this study suggests that tonic sympathetic nervous system activity in PTSD patients may not differ from that of healthy controls.