The co-occurrence of PTSD and dissociation: differentiating severe PTSD from dissociative-PTSD.
OBJECTIVE
A dissociative-posttraumatic stress disorder (PTSD) subtype has been included in the DSM-5. However, it is not yet clear whether certain socio-demographic characteristics or psychological/clinical constructs such as comorbid psychopathology differentiate between severe PTSD and dissociative-PTSD. The current study investigated the existence of a dissociative-PTSD subtype and explored whether a number of trauma and clinical covariates could differentiate between severe PTSD alone and dissociative-PTSD.


METHODS
The current study utilized a sample of 432 treatment seeking Canadian military veterans. Participants were assessed with the Clinician Administered PTSD Scale (CAPS) and self-report measures of traumatic life events, depression, and anxiety. CAPS severity scores were created reflecting the sum of the frequency and intensity items from each of the 17 PTSD and 3 dissociation items. The CAPS severity scores were used as indicators in a latent profile analysis (LPA) to investigate the existence of a dissociative-PTSD subtype. Subsequently, several covariates were added to the model to explore differences between severe PTSD alone and dissociative-PTSD.


RESULTS
The LPA identified five classes: one of which constituted a severe PTSD group (30.5 %), and one of which constituted a dissociative-PTSD group (13.7 %). None of the included, demographic, trauma, or clinical covariates were significantly predictive of membership in the dissociative-PTSD group compared to the severe PTSD group.


CONCLUSIONS
In conclusion, a significant proportion of individuals report high levels of dissociation alongside their PTSD, which constitutes a dissociative-PTSD subtype. Further investigation is needed to identify which factors may increase or decrease the likelihood of membership in a dissociative-PTSD subtype group compared to a severe PTSD only group.
School of Psychology, University of Ulster at Coleraine Campus, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK, armour.cherie@gmail.com.
Cherie
C
Armour
Karen-Inge
KI
Karstoft
J Don
JD
Richardson
D000328:Adult; D002170:Canada / Q000453:epidemiology; D015897:Comorbidity; D003863:Depression; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004213:Dissociative Disorders / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008889:Military Personnel / Q000523:psychology* / Q000706:statistics & numerical data; D012720:Severity of Illness Index; D013313:Stress Disorders, Post-Traumatic / Q000453:epidemiology* / Q000523:psychology; D014728:Veterans / Q000523:psychology* / Q000706:statistics & numerical data