<P> Around half of people with DID have less than 10 identities and most have less than 100; as many as 4,500 have been reported . The average number of identities has increased over the past few decades, from two or three to now an average of approximately 16 . However, it is unclear whether this is due to an actual increase in identities, or simply that the psychiatric community has become more accepting of a high number of compartmentalized memory components . The primary identity, which often has the patient's given name, tends to be "passive, dependent, guilty and depressed" with other personalities being more active, aggressive or hostile, and often containing a current time line that lacks childhood memory . Most identities are of ordinary people, though fictional, mythical, celebrity and animal parts have been reported . </P> <P> The psychiatric history frequently contains multiple previous diagnoses of various disorders and treatment failures . The most common presenting complaint of DID is depression, with headaches being a common neurological symptom . Comorbid disorders can include substance abuse, eating disorders, anxiety, posttraumatic stress disorder (PTSD), and personality disorders . A significant percentage of those diagnosed with DID have histories of borderline personality disorder and bipolar disorder . Further, data supports a high level of psychotic symptoms in individuals with DID, and that both individuals diagnosed with schizophrenia and those diagnosed with DID have histories of trauma . Other disorders that have been found to be comorbid with DID are somatization disorders, major depressive disorder, as well as history of a past suicide attempt, in comparison to those without a DID diagnosis . Individuals diagnosed with DID demonstrate the highest hypnotizability of any clinical population . The large number of symptoms presented by individuals diagnosed with DID has led some clinicians to suggest that, rather than being a separate disorder, diagnosis of DID is actually an indication of the severity of the other disorders diagnosed in the patient . </P> <P> The DSM - IV - TR states that acts of self - mutilation, impulsivity, and rapid changes in interpersonal relationships "may warrant a concurrent diagnosis of borderline personality disorder". Steven Lynn and colleagues have suggested that the significant overlap between BPD and DID may be a contributing factor to the development of therapy induced DID, in that the suggestion of hidden alters by therapists who propose a diagnosis of DID provides an explanation to patients for the behavioral instability, self - mutilation, unpredictable mood changes and actions they experience . In 1993 a group of researchers reviewed both DID and borderline personality disorder (BPD), concluding that DID was an epiphenomenon of BPD, with no tests or clinical description capable of distinguishing between the two . Their conclusions about the empirical proof of DID were echoed by a second group, who still believed the diagnosis existed, but while the knowledge to date did not justify DID as a separate diagnosis, it also did not disprove its existence . Reviews of medical records and psychological tests indicated that the majority of DID patients could be diagnosed with BPD instead, though about a third could not, suggesting that DID does exist but may be over-diagnosed . Between 50 and 66% of patients also meet the criteria for BPD, and nearly 75% of patients with BPD also meet the criteria for DID, with considerable overlap between the two conditions in terms of personality traits, cognitive and day - to - day functioning, and ratings by clinicians . Both groups also report higher rates of physical and sexual abuse than the general population, and patients with BPD also score highly on measures of dissociation . Even using strict diagnostic criteria, it can be difficult to distinguish between dissociative disorders and BPD (as well as bipolar disorder and schizophrenia), though the presence of comorbid anxiety disorders may help . </P> <P> The cause of DID is unknown and widely debated, with debate occurring between supporters of different hypotheses: that DID is a reaction to trauma; that DID is produced by inappropriate psychotherapeutic techniques that cause a patient to enact the role of a patient with DID; and newer hypotheses involving memory processing that allows for the possibility that trauma - causing dissociation can occur after childhood in DID, as it does in PTSD . It has been suggested that all the trauma - based and stress - related disorders be placed in one category that would include both DID and PTSD . Disturbed and altered sleep has also been suggested as having a role in dissociative disorders in general and specifically in DID, alterations in environments also largely affecting the DID patient . </P>

When was dissociative identity disorder added to the dsm