CSF norepinephrine concentrations in posttraumatic stress disorder

Objective. Despite evidence of hyperresponsive peripheral and central nervo us system (CNS) noradrenergic activity in posttraumatic stress disorder (PT SD), direct measures of CNS norepinephrine in PTSD have been lacking. The g oal of this study was to determine serial CSF norepinephrine levels in pati ents with PTSD. Method: CSF samples were obtained serially over a 6-hour period in 11 male combat veterans with chronic PTSD and eight healthy men through an indwelli ng subarachnoid catheter. Thus the authors were able to determine hourly CS F norepinephrine concentrations under baseline (unstressed) conditions. Sev erity of the patients' PTSD symptoms was assessed with the Clinician-Admini stered PTSD Scale. Results. CSF norepinephrine concentrations were significantly higher in the men with PTSD than in the healthy men. Moreover, CSF norepinephrine levels strongly and positively correlated with the severity of PTSD symptoms, Pla sma norepinephrine concentrations showed no significant relationship with t he severity of PTSD symptoms. Conclusions: These findings reveal the presence of greater CNS noradrenergi c activity under baseline conditions in patients with chronic PTSD than in healthy subjects and directly link this pathophysiologic observation with t he severity of the clinical posttraumatic stress syndrome.