Central nervous system norepinephrine (NE) is normally involved in blood pressure regulation, but it is pathophysiologically elevated in posttraumatic stress disorder (PTSD).
We monitored blood pressure while performing serial cerebrospinal fluid (CSF) sampling for 6 hours to determine CSF NE concentrations in men with combat-related PTSD (n = 11) and in healthy men (n = 8).
CSF NE concentrations strongly and positively correlated with mean diastolic blood pressure in the healthy men (R = 0.93, p < .002) but not in the patients (R = 0.10, p = .77). Within individuals, mean arterial pressure, systolic blood pressure, diastolic blood pressure and pulse pressure were poorly correlated over time in patients with PTSD but highly correlated over time in the healthy men, indicating that measurement of these hemodynamic parameters are poorly prognostic of subsequent measurements of the same parameter in patients with PTSD.
These data demonstrate the loss of the normal direct relationship between CSF NE and blood pressure in combat veterans with PTSD. Whether this dysynchrony mechanistically relates to the hemodynamic abnormalities in PTSD or, like some of the psychobehavioral symptoms, can be corrected with anti-noradrenergic pharmacotherapy remains to be determined.
NE = norepinephrine;
CNS = central nervous system;
PTSD = posttraumatic stress disorder;
CSF = cerebrospinal fluid;
MAP = mean arterial pressure;
BMI = body mass index;
AR = autoregressive order 1 model.