Dissociative Identity Disorder (DID), formerly referred to as multiple personality disorder, is characterized by the existence of 2 or more identities or personality traits within a single individual. Patients with this disorder demonstrate transfer of behavioral control among alter identities either by state transitions or by inference and overlap of alters who manifest themselves simultaneously. It is observed in 1-3% of the general population.

Mental status

DSM-IV diagnostic criteria for DID include the presence of 2 or more distinct identities or personality states, with at least 2 of these identities or personality states recurrently taking control of the person's behavior. Also, the inability of the patient to recall important personal information is too extensive to be explained by ordinary forgetfulness. In addition, the disturbance is not due to the direct physiologic effects of a substance or a general medical condition. Importantly, note that symptoms in children are not attributable to imaginary playmates or other fantasy play.

The dramatic and extreme patients with DID depicted in the media probably represent fewer than 5% of patients with this disorder. Most patients with DID have a covert and subtle presentation. The typical clinical presentation is one of a refractory psychiatric disorder, usually a mood disorder, or with multiple somatic symptoms. Patients have often received several psychiatric diagnoses over many years of treatment, such as bipolar disorder, PTSD, personality disorders, or various anxiety disorders.

Alter-identities vary in complexity and psychological structure. In some patients, highly developed alter-identities are present with marked presentational differences in posture, voice, mood, energy, interests, talents, capacities, manifest age, and even sex. However, in most cases, the alter-personalities are relatively limited in their depth and do not manifest dramatic differences. In general, all alter-identities should be held responsible for the behavior of each of the other alter-identities, despite subjective amnesia to the behavior.

DID is thought to begin in childhood in response to repeated traumatic and/or overwhelming life experiences, most of which involve physical and sexual abuse. Other traumatic events include long and painful childhood medical experiences and wartime dislocation. In studies of patients with DID, a range of 70% of patients to more than 95% of patients reported childhood abuse. However, some patients cause controversy because they revise their histories as treatment progresses.

Patients with DID typically also have DA. They cannot remember important life events. They have blackout phases and also experience fluctuations in personalities and talents. Some patients actually have variable blood pressures, blood glucose levels, changes in visual acuity, and variable responses to drugs and treatments with the shifting of identities.

Most patients with DID are diagnosed in adulthood. However, with new knowledge and awareness of the sequela of abuse, patients are now being diagnosed in childhood and adolescence.

The current view is that DID is a developmental posttraumatic disorder usually starting before age 6 years, although it is diagnosed much later. Traumatizing circumstances and poor relationships with caretakers disrupt the normal consolidation of personal identity across shifts in state, mood, and personal and social context. These traumatic memories are encapsulated to permit development in other areas of life such as academics and social life. These entities show some development separate from other identities. The outcome is a person embodying a number of relatively concrete independent self-states. These self-states are often in conflict with each other.

Differential diagnoses

When diagnosing DID, clinicians should also consider other disorders such as other dissociative disorders, mood disorder, personality disorders, schizophrenia, seizure disorder, eating disorders, malingering, and factitious disorders.

Schizophrenia is in the differential diagnosis because patients often hear voices; the difference is that they hear voices within their heads, not from outside. Careful history taking to recognize chronic amnesia, symptoms of PTSD, a history of maltreatment, and the presence of alter identities may allow making a diagnosis of DID even if other comorbid disorders are observed.

continue: Treatment of DID

top . pages 1 2 . send to friend . dissociative disorders site map

Reviewed: 04/2006