Dissociative identity disorder (DID), formerly known as multiple personality disorder, is a psychiatric condition characterized by the presence of ≥ 2 distinct alternating personality states that control a person’s behaviors and thoughts. While dominant, a personality is usually unaware of events that occurred during other personality states.
- Rare condition; prevalence in the United States: approximately 1%
- Women affected more than men
- Main risk factors are childhood sexual and physical abuse and psychogenic trauma.
- Comorbidities include:
- Substance use disorders
- Somatoform conditions
- Personality disorders—borderline personality and avoidant personality
- Trauma model:
- Early childhood trauma or abuse might lead to splitting off personalities as a way to cope with the trauma.
- 85%–97% of those with DID report history of severe childhood trauma.
- Sociocognitive model:
- Proposed that patients learn to construe themselves as multiple selves.
- Symptoms of DID are believed to be absorbed by patients through representations of DID in movies, books, and other media.
Diagnosis and Clinical Features
- Careful history taking, especially with multiple longitudinal assessments, as well as history from multiple sources, is the hallmark of correct diagnosis.
- Clinical diagnosis through meeting specific criteria:
- Presence of ≥ 2 distinct personality states
- Recurrent memory gaps (in everyday events, important personal information, and/or traumatic events)
- Disruption involves marked discontinuity in sense of self and sense of agency.
- Accompanied by related alterations in affect, behavior, consciousness, memory, perception, cognition, and/or sensorimotor functioning
- Changes are observed by others or reported by patient.
- Symptoms cause significant impairment.
- The disturbance is not a normal part of a broadly accepted cultural or religious practice.
- Substance use (alcohol), medical conditions (seizures), and other psychiatric conditions must be ruled out.
- Depersonalization: sense of detachment from self
- Derealization: sense of detachment from one’s surroundings
- Trance state: narrowing of awareness of immediate surroundings
- Self-alteration: sense that a part of one’s self is markedly different from other parts of one’s self
- Amnesia and gaps in memory
Management and Prognosis
- Main goal is to promote safety and reduce severity of symptoms. Physicians must mitigate the high risk of self-harm for those with DID.
- Most widely used approach
- Goal is to help patient tolerate past trauma.
- Also may include other behavioral therapy, e.g., cognitive therapy, eye movement desensitization and reprocessing (EMDR), and hypnosis
- Group therapy: more effective in carefully structured group composed of only with patients with DID
- Medication usually reserved for comorbidities (e.g., mood disorders or PTSD)
- Drug-assisted interviewing: Aim is disinhibition to help the patient speak more freely.
- Dissociative identity disorder is a chronic illness and has an incomplete recovery.
- Patients with earlier age at onset tend to have a poorer prognosis.
- Patients with undiagnosed or untreated DID are at higher risk of self-harm and suicide.
- Borderline personality disorder: cluster of mental diseases marked by splitting, self-harm, chronic feelings of emptiness, outbursts, and inability to sustain relationships. Individuals with borderline personality disorder have difficulties in handling everyday stresses, and their behavior can lead to serious issues with relationships and work. The persistent dysfunction in mood and interpersonal relationships found in borderline personality disorder is not as prevalent in those with DID because of the variability in personality style.
- PTSD: psychiatric disturbance seen after experiencing a life-threatening event. Symptoms last > 1 month and involve reexperiencing the event as flashbacks or nightmares, avoiding reminders, irritability, hyperarousal, and poor memory and concentration. In those with DID, there are dissociative symptoms that are not related to or arising from PTSD, such as amnesia of nontraumatic and normal everyday events.
- Malingering: not a medical disorder, but rather the behavior of an individual. Malingering is characterized by the intentional falsification of symptoms for an external benefit. Patients may either invent new ailments or exaggerate current symptoms. Those who falsify DID often have amnesia for socially unacceptable behaviors and exaggerate their symptoms in the presence of others.
- Schizophrenia: chronic mental health disorder that is characterized by positive symptoms (delusions, hallucinations, and disorganized speech or behavior) and negative symptoms (flat affect, avolition, anhedonia, poor attention, and alogia). Schizophrenia is associated with a decline in functioning lasting > 6 months. Those with DID may experience similar alterations in realities; however, these are often experienced in a personified way (from the viewpoint of another personality).
- Ross CA. (1991). Epidemiology of multiple personality disorder and dissociation. Psychiatr Clin North Am. https://pubmed.ncbi.nlm.nih.gov/1946021/
- Spanos NP. (1994). Multiple identity enactments and multiple personality disorder: a sociocognitive perspective. Psychol Bull. https://pubmed.ncbi.nlm.nih.gov/8078970/
- Sadock BJ, Sadock VA, Ruiz P. (2014). Dissociative disorders. Chapter 12 of Kaplan and Sadock’s Synopsis of Psychiatry: Behavioral Sciences/Clinical Psychiatry. Philadelphia: Lippincott Williams and Wilkins, pp. 451–464.
- Mitra P, Jain A. (2021). Dissociative identity disorder. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK568768/