Variability and severity of depression and anxiety in post traumatic stress disorder and major depressive disorder

In order to better characterize the similarities in and differences between the nature of the affective disturbance associated with Posttraumatic Stre ss Disorder (PTSD) and with Major Depressive Disorder (MDD), self-reported mood and anxiety ratings were examined in PTSD subjects, MDD subjects, and subjects without a psychiatric disorder while they were undergoing a chrono biologic study. Based on serial ratings on visual analogue scales over a 24 hr period, PTSD subjects showed comparable levels of depression as the MDD group, as measured by the mean and maximum levels of mood; however, they h ad greater mood variability, as measured by the range and coefficients of v ariation of the mood ratings. The MDD but not the PTSD group had significan tly lower mood variability than the non-psychiatric group, as measured fly the coefficients of variation. The PTSD group reported higher levels of anx iety than the non-psychiatric or MDD group bat showed no differences in any measure of variability of anxiety These findings suggest there are phenome nologic differences ist the affective symptoms experienced by patients with PTSD and with MDD and that mood variability may distinguish between them. (C) 2001 Wiley-Liss, Inc.