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Dissociative Disorders

Psychiatry - Classification & Disorders













Introduction:

Dissociative disorders are a fascinating group of disorders which is considered a myth by some and by some, a reality. Dissociation is defined as a disruption in the usually integrated functions of consciousness, memory, identity and perception of the environment (Mulder et al. 1998) leading to a fragmentation of the coherence, unity and continuity of the sense of self. Dissociative disorders were first officially classified as a separate diagnostic group in DSM-III (Tutkun et al. 1998). Besides being a disorder on its own, dissociation may accompany several psychiatric disorders as a confounding factor or co morbid disorder (Evren et al. 2007). Dissociative disorders may accompany several psychiatric disorders (Sar & Ross, 2006) including borderline personality disorder (Sar et al. 2003; Sar, Akyuz, Kugu, Ozturk, & Ertem-Vehid, 2006), obsessive–compulsive disorder (Lochner et al. 2004), posttraumatic stress disorder (Briere, Scott, & Weathers, 2005), acute stress disorder (Spiegel, Classen, & Cardena, 2000), eating disorders (Farrington et al. 2002), pathological gambling (Grant & Kim, 2003), kleptomania (Grant, 2004), and schizophrenia (Ross & Keyes, 2004). Traumatic childhood experiences play a major role in the development of dissociative disorders (Tutkun et al. 1998; Kluft, 1991; Spiegel, 1991). Regression analysis done in one of the studies indicated that dissociation in young adulthood was significantly predicted by observed lack of parental responsiveness in infancy, while childhood verbal abuse was the only type of trauma that added to the prediction of dissociation (Dutra et al. 2009). Substance use is suggested to be an important problem among patients with dissociative disorder (Evren et al. 2007; Ellason et al. 1996).

Other conditions that can mimic similar symptoms as dissociative disorders are Dementia, Substance induced, certain medical conditions such as Multiple sclerosis, temporal lobe epilepsy, head trauma and other psychiatric conditions such as Post Traumatic Stress Disorder, somatoform disorders, affective illnesses, anxiety disorders as well as malingering (Chu et al. 2005).

This chapter gives an overview of Dissociative disorders including clinical symptoms and classification, pathogenesis and management (assessment and treatment).

Phenomenology

Epidemiology

Several studies have shown that dissociative disorders may have been previously under diagnosed and a much higher prevalence is encountered. (Foote et al. 2006) The prevalence of dissociative disorders in general psychiatric settings ranges between 5.0% and 20.7% among inpatients (Sar et al. 2007) and between 12.0% and 29.0% among outpatients. (Sar et al. 2007) In an outpatient study (the only methodologically strong outpatient study) in Turkish outpatients Sar et al. found that 12% of Turkish outpatients could qualify for a diagnosis of a dissociative disorder, including 4% with dissociative identity disorder and 8% with dissociative disorder not otherwise specified. (Foote et al. 2006) Only 1% of those patients had been diagnosed with dissociative disorder before entering the study. (Foote et al. 2006) Inpatient populations have been studied more thoroughly as listed in Table 1. (Foote et al. 2006) In one of the studies, frequency of dissociative disorders was studied in the psychiatry emergency ward and noted to be as high as 34.9%. (Sar et al. 2006) Table 1. Studies of the prevalence of dissociative disorders in inpatient psychi-atric patients
Study Patients with Dissociative disorder (%) Patients with Dissociative Identity disorder (%)
Ross et al. 21 3-5
Saxe et al. 13 4
Horen et al. 17 6
Latz et al. 15 4
Knudsen et al. 8 7
Lussier et al. 9 7
Tutkun et al. 10 5
Rifkin et al. ? 1
Friedl and Draijer 8 2
Gast et al. 4-8 1-2

Clinical Symptoms and Classification

In International Classification of Diseases, 10th revision (ICD-10) dissociative disorders has been listed under the category of Neurotic, stress- related and somatoform disorders. It includes conversion, hysteria and hysterical psychosis and excludes malingering. As per ICD-10, in dissociative disorders there is a partial or complete loss of the normal integration between memories of the past, awareness of identity and immediate sensations, and control of bodily movements. They are presumed to be psychogenic in origin, being associated closely in time with traumatic events, insoluble and intolerable problems, or disturbed relationships. The symptoms cannot be attributed to any medical or neurological disorder excluded by physical exam and investigations. In addition, there is evidence that the loss of function is an expression of emotional conflicts or needs. Table 2. Classification and clinical symptoms of dissociative disorders (F44) as per ICD-10 criteria
ICD-10 Code Classification Symptoms Excludes
F44.0 Dissociative amnesia Loss of memory, usually of impor- tant events, not due to organic dis- order or ordinary fatigue/forgetful- nessCentered on traumatic events e.g., accidents or unexpected bereave- ments Psychoactive sub- stance induced amnesic disorder- NOSAnterograde, retrograde amne- siaNonalcoholic organic amnesic syndromePostictal amnesia in epilepsy
F44.1 Dissociative fugue Symptoms of dis- sociative amnesia + purposeful travel beyond the usual everyday range. Postictal fugue in epilepsy
F44.2 Dissociative stupor Profound diminu- tion or absence of voluntary move- ment & normal responsiveness to external stimuli such as light, noise & touch.Evidence of recent stressful event(s). Organic catatonic disorderStupor: • NOS • Catatonic • Depressive • manic
F44.3 Trance & Posses- sion disorders Temporary loss of the personal identity & full awareness of the surround- ings.Involuntary or unwanted. States associated with: • acute & tran- sient psychotic disorders • organic personal- ity disorder • postconcussional syndrome • psychoactive substance intoxi- cation • schizophrenia
F44.4 Dissociative motor disorders Loss of ability to move the whole or a part of a limb or limbs (most com- mon).AphoniaDysphonia
F44.5 Dissociative con- vulsions Epileptic seizures like movements but with maintenance of consciousness or replaced by a state of stupor or trance.Tongue bit- ing, urinary inconti- nence, bruising due to falling are rare.
F44.6 Dissociative anaes- thesia and sensory loss Anaesthetic areas of skin not corre- sponding to der- matomal distribu- tion.Sensory loss not explained by any neurological le- sion; may be accom- panied with pares- thesia.Psychogenic deafness.
F44.7 Mixed dissociative (conversion) disor- ders Combination of disorders specified in F44.0-44.6
F44.8 Other dissociative disorders Ganser’s syndrome- Multiple personali- tyPsychogenic • confusion • twilight state
F44.9 Dissociative (con- version) disorder, unspecified
The DSM-IV-TR talks about dissociative amnesia and fugue as part of dissociative disorders as included in the ICD-10 criteria but conversion disorder is a part of Somatoform disorders rather than dissociative disorders in the DSM-IV. Dissociative stupor, trance, convulsions, Ganser syndrome and motor disorders are all grouped together under Dissociative disorder NOS rather than being classified separately as in ICD-10. Dissociative Identity disorder, formerly known as multiple personality disorder is sub-classified as a part of "Other dis-sociative disorders" in ICD-10 whereas it has been classified separately in the DSM-IV. The American Psychiatric Association’s DSM-IV recognizes dissociative disorders as official diagnostic category; by contrast World Health Organization’s ICD-10 is more skeptical classifying dissociative disorders as conversion disorders and suggesting the dissociative identity disorder may be "a culture-specific or even iatrogenic condition." (Lalonde et al.2001) No matter what the differences are in the classification, the overall suggestibility of the symptoms and signs are the same and the same methods of assessment may be used to diagnose dissociative disorders.

Assessment

The first step is to do a detailed clinical interview including questions about significant childhood and adult trauma. Clinicians should use careful clinical judgment about how much detail of traumatic experiences to pursue during initial interviews, especially when those experiences seem to be poorly or incompletely remembered. A premature trauma anamnesis may evoke a florid decompensation (Chu et al. 2005). The patient should be asked about episodes of amnesia,fugue, depersonalization, derealization, identity confusion, and identity alteration, age regressions, autohypnotic experiences, hearing voices, passive-influence symptoms such as "made" thoughts, emotions, or behaviors and somatoform symptoms such as bodily sensations related to past trauma (Chu et al. 2005).

Measures of Dissociation

There are three classes of instruments that assess dissociation: Clinician-administered structured interviews, clinician-administered measures, and self-report instruments (Chu et al. 2005). Clinician-administered structured interviews The Structured Clinical Interview for DSM-IV Dissociative Disorders-Revised (SCID-D-R) (Bremner et al. 1993) is a 277-item interview that assesses five symptoms of dissociation: amnesia, depersonalization, derealization, identity confusion, and identity alteration. The SCID-D-R has good-to-excellent reliability and discriminant validity. The Dissociative Disorder Interview Schedule (DDIS) is a 132-item structured interview with a yes/no format that assesses the symptoms of the five DSM-IV dissociative disorders, somatization disorder, borderline personality disorder, and major depressive disorder. The DDIS also assesses substance abuse, Schneiderian first-rank symptoms, trance, childhood abuse, secondary features of Dissociative Identity Disorder, and supernatural/paranormal experiences. Clinician Administered Measures The Clinician Administered Dissociative States Scale (CADSS) (Bremner et al. 1998) has 27 items with 19 subject-rated items and 8 observer-scored items, all rated on a 0-4 scale. It has three factors that assess symptoms of amnesia, depersonalization and derealization. Self-Report Instruments There are six self-report measures of dissociation that have been used with some frequency (Chu et al. 2005): the Dissociative Experiences Scale [DES], the Questionnaire of Experiences of Dissociation [QED], the Dissociation Questionnaire [DIS-Q], Somatoform Dissociation Questionnaire [SDQ] and the Multiscale Dissociation Inventory [MDI]) Dissociative Experiences Scale (DES, Bernstein and Putnam, 1989) The Dissociative Experiences Scale is a widely used 28-item self-report measure for assessment of specific dissociative experiences (Bernstein et al. 1986, Carlson et al. 1993).Items are rated on a continuous scale (original version) or on an11-point Likert scale (revised version) that ranges from 0 ("never") to100 ("always"). DES items primarily tap absorption, imaginative involvement, depersonalization, derealization, and amnesia (Chu et al. 2005). The Questionnaire of Experiences of Dissociation (QED; Riley, 1988) is a 26-item, true/false self-report instrument-not very frequently used (Chu et al. 2005). The Dissociation Questionnaire (DIS-Q; Vanderlinden, Van Dyck,Vandereycken, Vetommen, & Verkes, 1993; Vanderlinden, 1993) is a 63-item, five-point Likert format, self-report instrument-commonly used in Europe (Chu et al. 2005). The Somatoform Dissociation Questionnaire-20 (SDQ-20) is a 20-item self-report instrument using a five-point Likert scale (Nijenhuis, Spinhoven,Van Dyck, Van der Hart, & Vanderlinden, 1996). The SDQ-20 is explicitly conceptualized as a measure of somatoform dissociation. The Multidimensional Inventory of Dissociation (MID) is a 218-item self-report, multiscale measure of pathological dissociation that makes diagnoses and yields a comprehensive dissociative profile (Dell, 2004). The MID is the only measure of dissociation that has validity scales: Defensiveness, Rare Symptoms, Attention-Seeking Behavior, Factitious Behavior, and Neurotic Suffering (Chu et al. 2005) The Multiscale Dissociation Inventory (MDI; Briere, 2002) is a 30-item multiscale measure of dissociation with a 5-point Likert format. The MDI is fully standardized, allowing t score comparisons to anormative group of trauma-exposed men and women. It yields six sub-scales–Disengagement, Depersonalization, Derealization, Emotional Constriction/Numbing, Memory Disturbance, and Identity Dissociation–and a total dissociation scale (Chu et al. 2005).

Other Psychological Tests

Along with more specific diagnostic testing (e.g., SCID-D-R, DES, etc.), standardized psychological tests (MMPI-2, Rorschach etc.) may aid the clinician in differential diagnosis and prognosis, the identification of co-morbid disorders, and the evaluation of treatment options (Chu et al. 2005).

Special investigations

No specific investigations are specific to Dissociative disorders. In one study, MRI revealed the amygdalar and hippocampal volumes to be smaller in females with Dissociative identity compared to healthy subjects (Vermetten et al. 2006). But the use of such expensive studies such as MRI is questionable to diagnose dissociative disorders, also when this finding is not specific to dissociative disorders. In another study it was documented that low serum lipid levels may be related to a high incidence of self-injurious behaviors and borderline features in patients with dissociative disorders (Agargun et al. 2004).

Other rating scales that are available for use to assess Dissociative disorders

Diagnostic Drawing Series (DDS) (Mills & Cohen, 1993 Adolescent Dissociative Experiences Scale-II (A-DES) Child Dissociative Checklist (CDC), Version 3 Peritraumatic Dissociative Experiences Questionnaire (PDEQ) Cambridge Depersonalization Scale Steinberg Deperson-alization Questionnaire Adolescent MID 6.0 Dissociative Features Profile (DFP)

Pathogenesis

The research regarding etiology of Dissociative Disorders is controversial. Several factors make it difficult to perform, especially the high co-morbidity of Dissociative Disorders with other psychiatric pathologies. The dissociation may be observed as a transient phenomenon secondary to a medical condition such as temporal lobe epilepsy (Bob, 2007). In addition, dissociative symptoms may be a part of the symptomatology of Substance Abuse, Borderline Personality Disorder, or Obsessive Compulsive Disorder. Some researchers even argue that Dissociative Disorders don’t exist as separate diagnoses at all and should be considered a part of post-traumatic psychopathology. As a general consensus, a link between dissociative symptoms in adulthood and self-reports of childhood traumatic events (including familial loss in childhood, sexual/physical abuse and neglect) has been documented.

Biological Factors

GENETICS To date, not many studies have been done to determine the genetic predisposition to Dissociative Disorders. Results of existing studies confirm that the dissociation may be partially genetically determined, although results of twin studies are controversial. One study, by Waller, 1997, found no evidence and another study, by Jang, 1998, found 48% to 55% genetic influence. A study by Savitz, 2008, found that there is involvement of COMT Val158Met polymorphism in mediating the relationship between pre-existing trauma and following development of dissociative psychopathology. NEUROBIOLOGY In the area of neurobiological research, multiple studies were done that confirm the presence of physiological changes associated with dissociative symptoms. As already mentioned, there is a hypothesis that early psychological trauma or abuse (i.e., stress) can mediate the development of those changes. To date, several neurotransmitter systems have been implicated in the development of Dissociative Disorders: Hypothalamo-Pituitary-Adrenal Dysfunction (HPA), Glutamate/N-methyl-D-aspartate (NMDA) receptor, Serotonin 5-HT2a, 5-HT2c, ?-aminobutyric acid (GABA), and Opioid receptors. The HPA axis is known to play a central role in medicating the stress response. Several studies on this have been done to date. Most of them presented similar findings showing that individuals with dissociative symptoms have basal HPA-axis hyperactivity with elevated cortisol and diminished pituitary negative-feedback inhibition (Simeon, 2006). As an extension of this dysregulation due to stress, some research was performed using neuroimaging. In both animal and human studies, stress at a young age has been shown to be associated with changes in the structure of the hippocampus. Smaller hippocampal and amygdalar volumes in patients with dissociative symptoms have been reported by some researchers (Vermetten, 2006). Decreased hippocampal volume may be explained by stress exposure; the hippocampus is a major target organ for glucocorticoids, which are released during stressful experiences, and prolonged exposure to glucocorticoids can lead to progressive atrophy of the hippocampus. The exact mechanism that can lead to smaller amygdalar volume is unclear. It is possible that other neurotransmitters play a role in this change. In their study, D’Souza et al. (2006) proposed that dissociative symptoms, similar to psychosis, may be related to the inhibitory (GABAergic) deficits that cause unopposed stimulation of serotonin receptors. Lysergic acid diethylamide (LSD), dimethyltryptamine (DMT) work as agonists of serotonin 5-HT2a and 5-HT2c receptors, again suggesting a possible mediating role for serotonin in dissociation. A similar mechanism might underlie cognitive effects of NMDA receptor antagonists, such as ketamine, which was found to cause a profound dissociative state in healthy individuals. NMDA receptors are widely distributed in the cortex, as well as in the hippocampus and the amygdala; therefore, it is possible that diminished NMDA-related neurotransmission may be related to dissociative states. The effect of cannabinoids confirm this hypothesis, as they have been shown to block NMDA receptors at sites distinct from other noncompetitive NMDA antagonists (Feigenbaum, 1989) and still cause dissociative symptoms. Several studies using positron emission tomography have been performed. One showed that depersonalization severity was correlated with an increase in cerebral blood flow (CBF) in the right frontal cortex and anterior cingulate, and a decrease in subcortical flow in the amygdala, hippocampus, basal ganglia and thalamus (Mathew, 1999). Reinders (2006) found psychobiological differences for the different dissociative identity states. Regional cerebral blood flow (rCBF) data revealed different neural networks to be associated with different processing of the neutral and trauma-related memory script. Sar et al. (2001, 2007) demonstrated decreased bilateral perfusion in frontal and occipital regions among patients with dissociative identity disorder (DID) compared with a group of non-traumatized healthy individuals, which the researchers think provides some validation of the existence of dissociative identity disorder as a distinct diagnostic category. These results also confirm the "orbito-frontal model" of Dissociative Identitiy Disorder proposed by Forrest (2001), which hypothesizes that the orbito-frontal cortex plays a critical role in the development of dissociative identities due to its inhibitory function. Research regarding the neurobiology of dissociative disorders is ongoing and continues.

Psychological Factors

There is growing interest in the role of early childhood disturbances of attachment and parenting in the development of dissociation (Dutra, 2009). From that article: "Bowlby, in 1973, suggested that infants may internalize dissociated or unintegrated internal working models of their primary caretakers, as well as of themselves. Main and Solomon (1990) then documented the existence of contradictory, confused, and disoriented behavior among some infants in the presence of the parent when needing comfort. These were termed disorganized/disoriented attachment behaviors. Subsequent meta-analyses have confirmed the association between infant disorganized attachment behavior, parental maltreatment, parental psychopathology, disturbed parent-infant interaction, and childhood behavior problems (Madigan et al. 2006; van IJzendoorn et al. 1999). Liotti (1992) further noted that there are suggestive parallels between infant disorganization and adult dissociation in that both phenomena reflect a pervasive lack of mental or behavioral integration." As discussed above in the "Biological Factors" section, early childhood trauma, loss or abuse are strongly correlated with the development of dissociative symptom. Along with the traumagenic theory of development of dissociative disorders, especially Dissociative Identity Disorder (DID), there are iatrogenic and pseudogenic positions (Reinders, 2006). The iatrogenic position takes the view that Dissociative Identity Disorder symptoms are often induced during psychotherapeutic treatment where there is good therapeutic alliance, high therapeutic dependency and high suggestibility. Therapy may contribute to the creation of false memories, and then separate and distinct identities, leading to the creation of Dissociative Identity Disorder phenomena. Laney and Loftus (2005) and Loftus and Davis (2006) describe cases where individuals that claimed to be amnestic had false memories that were "reconstructed" during therapy. Pseudogenic Dissociative Identity Disorder includes subjects who are simulating DID without any therapeutic intervention. It is a conscious process used for achieving secondary gain.

Social/Cultural Factors

CULTURAL FACTORS There is a growing body of research targeted at possible cultural differences, significance of the place of origin or other ethnical background in the development of dissociative disorders. Racial and ethnic differences were studied by Douglas (2009) in a non-clinical population and the results indicated differences in dissociation as a function of race: Africans and Asian Americans reported significantly higher rates of dissociation compared to Whites. A substantial proportion of recently published cases of dissociative disorders showed that immigration is an important factor in the development of DID (Staniloiu, 2009). Fatalism, trance, possession, spiritual and healing practices (Seligman, 2008; Moreira-Almeida A, 2008) are being studied. All this research can advance the ethnographic studies of dissociation and highlights the importance of social and cultural aspects of its development. JURISPRUDENCE One of the social aspects of debate is implication of DID in jurisprudence. This illustrates how iatrogenic and pseudogenic theories of development DID may be implicated. There are three categories of legal complications related to the diagnosis of dissociative disorders that the court system has to deal with (Reinders, 2006). Firstly, the individual suffering from DID may accuse another person of sexual or physical abuse. Secondly, the individual suffering form DID may claim not to be responsible for crimes committed in a different identity state. And, thirdly, if a person has multiple identities, which one can legally represent that person? FAMILIES To date, several family environmental factors were found to be associated with dissociation, including lack of parental care and warmth (Mann and Sanders, 1994; Modestin et al. 2002), inconsistent discipline (Braun and Sachs, 1985; Mann and Sanders, 1994), and poor relationship between parents (Maaranen et al. 2004). Additionally, all of these factors were also associated with abusive environments (Wolfe, l985). Familial and social support should be recognized as important protective factors against the development of DID (Korol, 2008).

Treatment

In treating patients with Dissociative Disorders, a variety of theoretical approaches are reported to be effective including cognitive behavioral therapy, hypnosis, psychopharmacolog-ical treatment, psychodynamic therapy, phenomenological treatment, contextual treatment, cognitive analytic therapy, feminist-informed treatment, and adjunctive treatment with Eye Movement Desensitization and Reprocessing (Brand et al. 2009). However, a review of the current literature examining the treatments for Dissociative Disorders illustrates a serious lack of well-designed studies on the treatment of Dissociative Disorders and a scarcity of controlled outcome research for Dissociative Disorder patients (Brand et al. 2009). A majority of the current information available regarding treatment recommendations for Dissociative Disorder is based off clinical and empirical evidence from case studies and case series. Although there are multiple approaches for treating Dissociative Disorders, the common element of these treatments addresses the dissociative pathology and exploring prior traumatic events. Treatment of Dissociative Disorders is associated with improvements in symptoms of dissociation, depression, general distress, anxiety and PTSD, as well as decreased use of medications and improved work and social functioning (Brand et al. 2009). Duration of treatment varies depending on the particular Dissociative Disorder being treated, with Dissociative Amnesia and Dissociative Fugue recovering more quickly and having a better outcome as compared to Dissociative Identity Disorder and Depersonalization Disor-der. However, a significant proportion of patients’ improvement during initial treatment may not remain stable over time, indicating the need for additional follow up for contingent intervention in the case of recurrent dissociative symptoms or other psychopathological states (Jans et al. 2008).

Psychotherapy

Overall, the most common form of treatment for the Dissociative Disorders is psychotherapy, which generally focuses on the dissociative psychopathology and associated trauma or stressor. Many different types of psychotherapy have been used in the treatment of Dissociative Disorders, including psychodynamic, cognitive behavioral, supportive, hypnotherapeutic, free association and drug assisted. Dissociative Disorder patients often present with challenging symptomatology and one must be flexible in the approach and technique applied (Turkus and Kahler, 2006). It is crucial to recognize the devastating effects that the past trauma or stressor has had on the patient’s life and their current state of dysfunction (Turkus and Kahler, 2006). Applying skill-building interventions at the beginning stages of treatment helps stabilize the patient and ameliorate the disabling dissociative symptoms, allowing treatment to progress and help patients to cope with painful affect and recollections of the traumatic experience (Turkus and Kahler, 2006). As psychotherapeutic techniques are applied in treatment, it is important to remember not to overwhelm the patient by forcing the intervention or insisting on following a preset time length for the treatment process as each patient’s progress may vary. Patients with Dissociative Amnesia and Dissociative Fugue generally recover more quickly, especially when the dissociative event is of short duration, and their symptoms may even resolve spontaneously when the individual is removed from the precipitating trauma or stressor. However, longer-lasting episodes become more difficult to treat and may be intractable (Stern et al. 2008). Clinicians should try to restore patients’ memories to consciousness as soon as possible; otherwise, the repressed memory may form a nucleus in the unconscious mind around which future dissociative episodes may develop (Sadock and Sadock, 2007). Treatment of Dissociative Amnesia is aimed at the restoration of missing memories while treatment of Dissociative Fugue is focused on the recovery of memory for identity and events preceding the fugue. Cognitive and psychodynamic are the most common psychotherapy techniques applied in treatment of Dissociative Amnesia and Dissociative Fugue; however, hypnotherapy and pharmacologically facilitated interviews are frequently necessary adjunctive techniques to assist with memory recovery (Sadock and Sadock, 2007). In treating patients with Dissociative Identity Disorder, extended psychotherapy remains the treatment of choice, although approaches vary widely and remain controversial (Stern et al. 2008). Successful psychotherapy requires the clinician to be comfortable with a range of psychotherapeutic interventions (psychoanalysis, psychodynamic therapy, cognitive therapy, behavioral therapy, hypnotherapy, etc.) and be willing to actively work to structure the treatment (Sadock and Sadock, 2007). Comfort with family treatment and systems theory is helpful in working with a patient who subjectively experiences himself or herself as a complex system of selves with alliances, family-like relationships and intragroup conflicts (Sadock and Sadock, 2007). Some clinicians approach treatment by delineating and mapping the alternate identities, inviting each to participate in the treatment, and facilitating communication between the various identities in an attempt to understand past episodes of trauma as experienced by each identity (Stern et al. 2008). Other clinicians focus on the function of the dissociative process in the here-and-now of the patient’s life and the ongoing treatment (Stern et al. 2008). They help patients become aware of using dissociation to manage feelings and thoughts within themselves and to manage the closeness and distance within relationships (Stern et al. 2008). All approaches seek to increase affect tolerance and to integrate the dissociated states within the patient (Stern et al. 2008). Patients with Dissociative Disorder who integrated their dissociated self states were found to have reduced symptomatology compared with those who did not integrate (Brand et al. 2009). Treatment of Depersonalization Disorder is difficult and patients are often refractory to interventions (Stern et al. 2008). A variety of psychotherapeutic techniques can be used to treat Depersonalization Disorder, although none of these have established efficacy (Simeon, 2004). Treatment of accompanying psychiatric conditions (such as depression or anxiety)may help and, as with other dissociative disorders, exploration of prior traumatic events may prove useful (Stern et al. 2008; Simeon, 2004).

Pharmacotherapy

Overall, the use of pharmacotherapy in the treatment of Dissociative Disorders is limited and controversial, as most medications (such as antidepressants and anxiolytics) are initi-ated to alleviate comorbid anxiety and mood symptoms, but do not treat the dissociative psychopathology. Currently, no pharmacological treatment has been found to reduce disso-ciation, per se (Stern, Rosenbaum et al. 2008). Although antidepressant medications are useful in the reduction of depression and stabilization of mood, one must be cautious in using benzodiazepines to reduce anxiety as they can also exacerbate dissociation (Sadock and Sadock, 2007; Stern, Rosenbaum et al. 2008). Presently, no specific pharmacotherapy exists for the treatment of Dissociative Amnesia and Dissociative Fugue other than pharmacologi-cally facilitated interviews. A variety of agents have been used for this purpose, including sodium amobarbital, thiopental, benzodiazepines and amphetamines (Sadock and Sadock, 2007). This procedure is generally used for more acute cases, but can be occasionally useful in refractory cases of chronic dissociative amnesia when patients are unresponsive to other interventions (Sadock and Sadock, 2007). The material uncovered in a pharmacologically facilitated interview needs to be processed by the patient in his or her usual conscious state. In treating patients with Dissociative Identity Disorder using pharmacotherapy, there are reports of some success with selective serotonin reuptake inhibitors, tricyclic antidepressants, monoamine oxidase inhibitors, ?-blockers, clonidine, anticonvulsants, and benzodiazepines in reducing intrusive symptoms, hyperarousal, anxiety and mood instability (Sadock and Sadock, 2007; Stern, Rosenbaum et al. 2008). Atypical antipsychotics have also been used for mood stabilization, overwhelming anxiety and intrusive PTSD symptoms in patients with Dissociative Identity Disorder, as they may be more effective and better tolerated than typical antipsychotics. Although not routinely used, other possible suggestions for pharmacologically treating Dissociative Identity Disorder include the use of prazosin in reducing nightmares, carbamazepine to reduce aggression, and naltrexone for amelioration of recurrent self-injurious behaviors (Sadock and Sadock, 2007). With regards to pharmacotherapy for Depersonalization Disorder, no medication has been shown to be efficacious to date, although research has been limited, and thus no definitive medication treatment guidelines exist (Simeon, 2004). Previous studies had suggested a possible role for serotonin reuptake inhibitors in treating primary Depersonalization Disorder, but unfortunately a more recently completed placebo-controlled trial, failed to show benefit with fluoxetine in 54 patients with Depersonalization Disorder (Simeon, 2004). As with the other Dissociative Disorders, treatment of comorbid anxiety and mood instability with antidepressants and anxiolytics may be useful.

Combined Treatment

Although psychotherapy is the most common and efficacious treatment approach for treating the Dissociative Disorders, it is not uncommon to combine psychotherapeutic technique and pharmacological management in clinical practice. Reducing the patients’ comorbid anxiety and mood instability with antidepressants and anxiolytics may help stabilize the patient overall and allow psychotherapy to progress, as well as help patients cope with painful affect and recollections of the traumatic experience as they arise.

Special Populations

Dissociative disorders can be a difficult set of disorders to diagnose due to their significant comorbidities and overlap with other psychiatric and medical diagnoses. Studies show a range of inpatient prevalences of 5% to 21% with outpatient prevalences ranging from 12% to 29%, which highlights the difficulty in accurate diagnosis (Brand et. al 2009). Dissociative disorders are shown to have significant comorbidity with multiple other psychiatric disorders that should be screened for including depression, borderline personality disorder, social anxiety, and somatization disorders (Evren et. al 2007) (Evren et. al 2009). More research needs to be done with dissociative populations to draw more firm conclusions, but many correlations have been gathered. Special populations that should be considered in relation to dissociative disorders include suicidal/self-mutilating, traumatized, eating disordered, substance abusing, and pediatric groups.

Suicidal and Self-Mutilating Populations

Both suicide attempts and self-mutilating behavior fall into the broader category of self-harm. While the difference between a suicidal or parasuicidal (self-mutilating) action may not always be easy to distinguish clinically, by definition they are quite distinct. Self-mutilation involves self-harm with no goal of suicide, while suicidal actions are meant to bring about one’s death. There is a fair amount of evidence supporting a relationship between dissociative disorder and suicide ideations/attempts. In one study of drug dependent patients there is a statistically significant increase in suicide attempts when comparing patients with dissociative disorder diagnoses to those without them (Tamar-Gurol et al. 2008). Another study showed that among patients with multiple suicide attempts, dissociative disorders are the strongest predictors of multiple suicide attempts when compared with borderline personality disorder, posttraumatic stress disorder, and alcohol abuse/dependence (Foote et al. 2008). With frequent comorbidity, there can be significant overlap between dissociative disorders, other psychiatric disorders, and suicidal behaviors. While there appears to be a link between dissociative disorders and suicidal ideations, a comorbid diagnosis of somatization disorder with dissociative disorder is a significant predictor of suicidal ideation (Ozturk and Sar, 2008). While suicidal behavior can be present in each specific dissociative disorder, it is particularly prevalent in Dissociative Identity Disorder possibly due to decreased affect tolerance (Kaplan and Sadock, 2007). While self-mutilation and suicide attempts are distinct entities, nearly 55% to 85% of people with self-mutilating behavior have made a suicide attempt (Evren et al. 2008). Thus with dissociative disorders carrying such a high risk for suicidal behaviors, it comes as no surprise that they also increase the risk for self-mutilation. Among alcohol dependent patients, those placed within a dissociative group based on results of Dissociative Experiences Scales were at higher risk for self-mutilation (Evren et al. 2008).

Traumatized Population

Traumatic events are a common factor in many psychiatric diagnoses including anxiety disorders, such as posttraumatic stress disorder, and personality traits like borderline personality disorder. A history of traumatic experience is quite common among all of the various dissociative disorders as well. Studies have shown a statistically greater incidence of emotional abuse among subsets with dissociative diagnoses than those without such diagnoses (Tamar-Gurol et al. 2008). However, the nature of the trauma can be quite diverse or specific from one dissociative diagnosis to the next. Dissociative fugue states are frequently seen around times of natural disasters, or during wartime among military personnel. Childhood trauma, usually of physical or sexual nature, is seen in 85% to 97% of patients with Dissociative Identity Disorder. Dissociative amnesia is often due to abuse; however, it can be related to wartime experiences as well. Like posttraumatic stress disorder, the severity of symptoms is highly correlated with the intensity of the combat (Kaplan and Sadock, 2007). With the correlation of traumatic experiences and dissociative disorders, presence of one should warrant screening for the other.

Eating Disordered Population

Many impulsive behaviors have been associated with dissociative disorders, and pathologic eating behaviors are included in this set. In fact, dissociative symptoms are frequently described in individuals with bulimic disorders (Waller et al. 2001). Among the various dissociative diagnoses, it appears that eating disorders are most prevalent with dissociative identity disorder (Kaplan and Sadock, 2007). One study looked at groups of women with eating disorders ranging from anorexia, anorexia with binge-purge subtype, bulimia nervosa, and binge-eating. These women were then administered Dissociative Experiences Scales (DES) to identify those with the most significant dissociative features. Findings showed the binge-purge subtype of anorexia to have the greatest proportion of dissociative cases while binge-eating disorder patients were lower and similar to control groups (Waller et al. 2001). Other factors like abuse or trauma may confound the analysis of studies like these. However, there appears to be a correlation between dissociative disorders and impulsive behaviors, which includes eating disorders.

Substance Abusing Population

Substance abuse is a common comorbidity with multiple psychiatric disorders including mood, anxiety, and psychotic disorders. Among those with dissociative disorders, substance abuse is frequently reported. However, studies show varied results in regards to their association. One study included inpatients with drug dependence (marijuana, cocaine, heroine, ecstacy, solvents) that often had comorbid alcohol dependence as well. The prevalence of dissociative disorders among the drug dependent inpatients was significantly higher than the general psychiatric inpatient population, showing correlation between the two (Tamar-Gurol, 2008). Another study included inpatients with alcohol dependence excluding any other comorbid drug abuse. Here the percentage of dissociative disorders among alcohol dependent patients was very similar to the general psychiatric inpatient population. This confers no increased risk of dissociative disorders among alcohol dependent inpatients (Evren et al. 2005). The reason for the difference seen between alcohol versus drug dependence is not known. However, both studies show that dissociative symptoms were present in a majority of the population before alcohol or drug use, 90% and 59.3% respectively (Evren et al. 2005)(Tamar-Gurol, 2008). This emphasizes the importance of screening for dissociative symptoms to potentially help prevent the progression to substance abuse or dependence.

Pediatric Population

Though pediatric populations are not frequently diagnosed with dissociative disorders, this subgroup may experience the trauma later associated with dissociative diagnoses. One study of drug dependent patients evaluated several variables between groups with dissociative disorders and those without them. Aside from suicide attempts, the only variable to reach statistical significance for increased risk for dissociative diagnoses was emotional abuse taking place during childhood (Tamar-Gurol, 2008). Another study showed that even among children and adolescents treated for dissociative disorders, 82.6% met the criteria for psychiatric disorders at an average of twelve years later. Nearly half of these had diagnosed personality disorders with significantly lower psychosocial adjustment in adulthood (Jans et al. 2008). Thus, recognizing childhood trauma and dissociative symptoms may prove helpful in starting early treatment to help adult adjustment and functioning. As often is seen in pediatric populations, there are sometimes differences in expression of symptoms between children and adults. In dissociative identity disorder children are noted to be less able to distinguish lapses in time and abnormal behaviors, and often teachers and relatives document these changes. In dissociative fugue adults are often noted to travel large distances or for prolonged periods of time. However, children and adolescents are often much more limited in this capacity and their fugues are often of shorter distances or of shorter duration (Kaplan and Sadock, 2007).

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