Exact incidence is unknown, with estimates around 2% or more of the general population, and women are more commonly diagnosed. Earlier onset of symptoms is associated with increased severity. A childhood history of abuse or neglect is common and often overlooked or minimized. Risk factors include physical or emotional abuse, as well as exposure to combat, violence, or natural disasters.
The presenting features for all dissociative disorders include temporary alterations in the patient's relation to reality. Dissociative identity disorder presents with 2 or more distinct personality states (formally multiple personality disorder); dissociative amnesia presents with partial or complete loss of memory for psychologically stressful events; dissociative amnesia with fugue state presents with sudden, unexplained travel and inability to recall features of one's past or identity; and dissociative depersonalization / derealization presents with the sensation of an out-of-body experience or feeling completely detached from one's self or surroundings.
Comorbid conditions include mood disorders, anxiety disorders, posttraumatic stress disorder, and functional neurological disorders. Suicide is common among patients with dissociative disorders, especially dissociative identity disorder.
Dissociative disorders can be transient or recurrent. Treatment includes psychotherapy and medication. Patients with these disorders may have an increased risk of various general medical conditions.
F44.9 – Dissociative and conversion disorder, unspecified
44376007 – Dissociative disorder
Differential Diagnosis & Pitfalls
- Mood disorders – including depression and bipolar disorder; may be associated with personality changes, abnormal behaviors, alterations in cognition, or memory loss
- Anxiety disorders (see generalized anxiety disorder) – can present with transient depersonalization during an acute panic attack
- Posttraumatic stress disorder – may present with amnesia or depersonalization / derealization
- Psychotic disorders – manifestations of dissociative disorders may be confused with symptoms of psychotic disorders, eg, hallucinations
- Conversion disorder (see somatic symptom and related disorders) – functional neurologic symptoms typically present without changes in behavior, personality, and memory and can involve other neurologic symptoms
- Personality disorders – especially borderline personality disorder, which is differentiated by the persistence of the personality traits, whereas dissociative identity disorder is characterized by longitudinal variability in personality
- Neurocognitive disorders including frontotemporal dementia or other dementias – patients present with drastic personality changes and memory loss later in life; time course is progressive rather than static or fluctuating
- Seizures – memory loss does not persist after postictal state
- Transient global amnesia – sudden memory loss and confusion, not as closely associated with history of trauma; resolves within hours to a couple of days and is rarely recurrent
- Delirium – acute changes in metal status
- Wernicke-Korsakoff syndrome – confusion, memory loss, and confabulation associated with physical symptoms including ataxia and abnormal eye movements
- Substance use / medications – hallucinogens, marijuana, cocaine, and other drugs can cause memory loss or depersonalization experiences
- Medical conditions – some conditions can cause changes in cognition, memory, and/or behavior, eg, endocrine encephalopathies