The National Comorbidity Study NCS (Kessler et al., 1995) found that 59% of men and 44% of women with PTSD met criteria for three or more other psychiatric diagnoses. Fourteen percent of men had two other diagnoses, 17% had one, with only 12% having no co-morbid diagnosis. The percentages for women were 18% with two other diagnoses, 17% with one and 21% with no co-morbidity. The most common co-morbid diagnoses were: affective disorders (especially depression); other anxiety disorders (such as generalised anxiety disorder, panic disorder, obsessive compulsive disorder and speciﬁc phobias); and substance use disorders, although the structured interview did not assess dissociation. Many Complex PTSD presentations are so enmeshed in co-morbid factors that the traumatic antecedents can be readily neglected by clinicians insistent on a phenomenological rather than an aetiological nosology. There is a relative paucity of data on the occurrence, duration and prognosis of other post-trauma psychological conditions, whether co-morbid or occurring in the absence of PTSD. For DID the co-morbidity problem is greater, as noted by the ISST-D (Chu et al., 2011):
“. . . the typical DID patient presents a polysymptomatic mixture of dissociative and PTSD symptoms that are embedded in a matrix of ostensibly non-trauma-related symptoms (e.g. depression, panic attacks, substance abuse, somatoform symptoms, eating-disordered symptoms). The prominence of these latter, highly familiar symptoms often leads clinicians to diagnose only these comorbid conditions. When this happens, the undiagnosed DID patient may undergo a long and frequently unsuccessful treatment for their other conditions.”
Even when dissociative disorders are of signiﬁcant severity, the diagnosis remains elusive with only those believing that the diagnosis is of utility likely to diagnose, a fate PTSD has also encountered. Research has shown both PTSD and sub-syndromal PTSD have higher suicide risk (e.g., Kessler, 2000), with or without major depression; the earlier the onset of childhood sexual abuse, the greater the suicidal intent (Lopez-Castroman et al., 2015).
(Extracted from) The Comprehensive Resource Model: Effective Therapeutic Techniques for the Healing of Complex Trauma, written by Lisa Schwarz, Frank Corrigan, Alastair Hull and Rajiv Raju, published by Routledge, 2017