Depersonalization disorder
Synonyms and keywords: Derealization disorder; depersonalization disorder; dissociative disorder; depersonalization/derealization disorder

# Overview
Depersonalization Disorder (DPD) is a dissociative disorder in which sufferers are affected by persistent feelings of depersonalization. The symptoms include a sense of automation, feeling a disconnection from one's body, and difficulty relating oneself to reality.  Occasional moments of depersonalization are normal, but a persistent feeling is not. Brief periods of depersonalization are notably caused by stress, a lack of sleep, or a combination.  It becomes a disorder when the dissociation interferes with the social and occupational functions necessary to everyday living. Often a victim of DPD feels as if he or she is going insane, though this is almost never the case.  Depersonalization disorder is often associated as a comorbid disorder of anxiety disorders, panic disorders, clinical depression, and/or bipolar disorder.  Anxiety can exacerbate depersonalization symptoms. In addition, DPD can cause anxiety since the person feels abnormal and uneasy at the loss of their sense of self.  Reality testing remains intact during episodes and continuous depersonalization, meaning that a person suffering from the disorder will be able to respond to questions and interact normally with his or her environment. This fact can be distressing for those with DPD; the friends and family of the victim do not realise that anything is wrong, because a person with DPD will usually not be visibly distraught.  While a nuisance, and very distressing to the sufferer, people with depersonalization disorder represent no risk to society, since their grasp on reality remains intact.

# Historical Perspective
The word depersonalization itself was first used by Henri Frederic Amiel in The Journal Intime.  The July 8, 1880 entry reads: "I find myself regarding existence as though from beyond the tomb, from another world; all is strange to me; I am, as it were, outside my own body and individuality; I am depersonalized, detached, cut adrift. Is this madness?" (Emphasis added)

# Pathophysiology
Not much is known about the neurobiology of depersonalization disorder, however a few studies may explain the subjective sense of detachment that forms the core of this dissociative experience.  A PET scan found functional abnormalities in the visual, auditory, and somatosensory cortex, as well as areas responsible for an integrated body schema.  In an fMRI study of DPD patients, emotionally aversive scenes activated the right ventral prefrontal cortex.  Participants demonstrated a reduced neural response in emotion-sensitive regions, as well as an increased response in regions associated with emotional regulation.  In a similar test of emotional memory, depersonalization disorder patients did not process emotionally salient material in the same way as healthy controls. In a test of skin conductance responses to unpleasant stimuli, the subjects showed a selective inhibitory mechanism on emotional processing.
Depersonalization disorder may be associated with dysregulation of the hypothalamic-pituitary-adrenal axis, the area of the brain involved in the "fight-or-flight" response.  Patients demonstrate abnormal cortisol levels and basal activity.  Studies found that patients with DPD could be distinguished from patients with clinical depression and posttraumatic stress disorder.

# Causes
Depersonalization disorder has been associated with childhood interpersonal trauma.  Emotional abuse is a significant predictor of depersonalization disorder and depersonalization symptoms.
Depersonalization is the third most common psychological experience, after feelings of anxiety and feelings of depression, and often occurs after life threatening experiences, such as accidents, assault, or serious illness or injury. The most common immediate precipitants of the disorder are severe stress, depression and panic, and marijuana and hallucinogen ingestion.

# Epidemiology and Demographics

## Prevalence
The prevalence of depersonalization/derealization is 2,000 per 100,000 (2%) of the overall population.

## Gender
Men and women are affected equally by DPD.

## Age
The average age of onset during the teenage years or early 20s, although some report being depersonalized as long as they can remember, and others report a later onset.

# Differential Diagnosis
- Anxiety disorders
- Brain tumour or lesion
- Illness anxiety disorder
- Major depressive disorder
- Mental disorders due to another medical condition
- Migraine
- Obsessive-compulsive disorder
- Other dissociative disorders
- Psychotic disorders
- Substance/medication-induced disorders:*Ecstasy
- Hallucinogens
- Ketamine
- Marijuana
- Salvia
- Temporal Lobe Epilepsy
- Transcendental meditation

# Risk Factors
- Anxiety
- Childhood interpersonal traumas
- Depression
- Emotional abuse
- Emotional neglect
- Growing up with a seriously impaired,mentally ill parent
- Illicit drug use
- Hallucinogens
- Ketamine
- MDMA
- Salvia
- Tetrahydrocannabinol
- Physical abuse
- Severe stress
- Sexual abuse
- Unexpected death or suicide of a family member or close friend
- Witnessing domestic violence

# Natural History, Complications and Prognosis
The onset can be acute or insidious.  With acute onset, some individuals remember the exact time and place of their first experience of depersonalization.  This may follow a prolonged period of severe stress, a traumatic event, an episode of another mental illness, or drug use.  Insidious onset may reach back as far as can be remembered, or it may begin with smaller episodes of lesser severity that gradually become stronger.  This disorder is episodic in about one-third of individuals, with each episode lasting from hours to months at a time. Depersonalization can begin episodically, and later become continuous at constant or varying intensity.

# Diagnosis
The diagnosis of DPD can be made with the use of various interviews and scales.  The Structured Clinical Interview for DSM-IV Dissociative Disorders (SCID-D) is widely used, especially in research settings.  This interview takes about 30 minutes to 1.5 hours, depending on individual's experiences.
The Dissociative Experiences Scale (DES) is a simple, quick, self-administered questionnaire that has been widely used to measure dissociative symptoms.  It has been used in hundreds of dissociative studies, and can detect depersonalization and derealization experiences.
The Dissociative Disorders Interview Schedule (DDIS) is a highly structured interview which makes DSM-IV diagnoses of somatization disorder, borderline personality disorder and major depressive disorder, as well as all the dissociative disorders. It inquires about positive symptoms of schizophrenia, secondary features of dissociative identity disorder, extrasensory experiences, substance abuse and other items relevant to the dissociative disorders. The DDIS can usually be administered in 30-45 minutes.

## DSM-V Diagnostic Criteria for Depersonalization/Derealization Disorder 

## DSM-IV Diagnostic Criteria for Depersonalization/Derealization Disorder
The diagnostic criteria defined in section 300.6 of the Diagnostic and Statistical Manual of Mental Disorders are as follows:
- Persistent, recurring feeling of being detached from ones mental processes or body; as if an observer
- During depersonalization, reality testing is intact
- Depersonalization causes significant distress, and impairment in social, occupational, or other functioning
- Depersonalization is not related to another disorder, substance use, or general medical condition

# Symptoms
The core symptom of depersonalization disorder is the subjective experience of unreality. Common descriptions are: watching oneself from a distance; out-of-body experiences; a sense of just going through the motions; feeling as though one is in a dream or movie; not feeling in control of one's speech or physical movements; and feeling detached from one's own thoughts or emotions.  These experiences may cause a person to feel uneasy or anxious since they strike at the core of a person's identity.
Sufferers retain the ability to distinguish between their own internal experiences and the objective reality of the outside world.
Some of the more common factors that exacerbate dissociative symptoms are negative affects, stress, subjective threatening social interaction, and unfamiliar environments.  Factors that tend to diminish symptoms are comforting interpersonal interactions, intense physical or emotional stimulation, and relaxation.
Fears of going crazy, brain damage, and losing control are common complaints.  Individuals report occupational impairments as they feel they are working below their ability, and interpersonal troubles since they have an emotional disconnection from those they care about.  Neuropsychological testing has shown deficits in attention, short-term memory and spatial-temporal reasoning.
An analogy is comparing real life to a game, a game everyone plays, all the time. Someone suffering from depersonalization disorder constantly feels as if they cannot get into the game; any stimulus feels contrived or artificial to them. The rules of this game seem to have been forcibly applied upon them (anything from movement, to gravity or hunger) instead of being inherently applicable to them. If understanding dawns upon them of what they should be experiencing, it is often through reason and observation, or the feeling of knowing what and why it is happening. This sort of insight seems to rob everything of its spontaneity, its importance already having been diminished because of their sense of detachment. They are perpetual, and almost all the time, involuntary, cynics of our reality.

# Treatment
To date, no treatment recommendations or guidelines for depersonalization disorder have been established. A variety of psychotherapeutic techniques has been used to treat depersonalization disorder (including trauma-focused therapy and cognitive-behavioural techniques), although none of these have established efficacy to date. Clinical pharmacotherapy research continues to explore a number of possible options.
Naloxone was used in a pilot study in 11 patients with chronic DPD.  Of the 11 patients, three experienced complete remission, and seven had marked improvement of depersonalization symptoms. The study only reported immediate treatment results, which makes the efficacy of continued treatment unknown.  Naloxone can only be administered intravenously, which makes long-term treatment difficult.  Naltrexone was used in a preliminary study in 14 individuals with DPD. Participants were treated for 6-10 weeks, at a fairly high average dose of 120 milligrams per day.  Three individuals were very much improved, another one was much improved, and on average a 30% decrease in depersonalization symptoms were reported. In another study in borderline personality disorder, doses of 200 milligrams per day of naltrexone was reported to decrease general dissociative symptoms over a 2-week period of treatment.
In a retrospective report of 117 subjects with DPD, 18 of 35 benzodiazepine trials were reported to have led to slight or definite improvement. Some individuals anecdotally appear to benefit from clonazepam in particular.  These drugs are not known to affect the symptoms of dissociation at all, however they do target the often co-morbid anxiety and stress experienced by those with DPD. To date no clinical trials have studied the effectiveness of benzodiazepines.
A series of small studies in the past decade have suggested a possible role of selective serotonin reuptake inhibitors in treating primary depersonalization disorder.  However, a recently completed placebo-controlled trial failed to show benefit with fluoxetine in 54 patients with depersonalization disorder.   SSRI treatment created an overall improvement in participants, but only by reducing anxiety and depression.  Clomipramine is a tricyclic antidepressant that is helpful with both depression and obsessional disorders.  In a study of four subjects treated with clomipramine, two showed clinically significant improvement of DPD.