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 important events, not due to organic disorder or ordinary fatigue/forgetfulness
Centered on traumatic events e.g., accidents or unexpected
Psychoactive substance induced amnesic disorder
NOS Anterograde, retrograde amnesia Nonalcoholic organic amnesic syndrome Postictal amnesia in epilepsy
bereavements F44.1 Dissociative
fugue
Symptoms of dissociative amnesia + purposeful travel beyond the usual everyday range.
Postictal fugue in epilepsy
F44.2 Dissociative stupor
Profound diminution or absence of voluntary movement & normal responsiveness to external stimuli such as light, noise & touch.
Evidence of recent stressful event(s).
Organic catatonic disorder Stupor: NOS Catatonic Depressive manic F44.3 Trance & Possession disorders
Temporary loss of the personal identity & full awareness of the surroundings.
Involuntary or unwanted.
States associated with:
acute & transient psychotic disorders
organic personality disorder
postconcussional syndrome psychoactive substance intoxication schizophrenia F44.4 Dissociative motor disorders
Loss of ability to move the whole or a part of a limb or limbs (most common). Aphonia Dysphonia
F44.5 Dissociative convulsions
Epileptic seizures like movements but with
maintenance of consciousness or replaced by a state of stupor or trance.
Tongue biting, urinary incontinence, bruising due to falling are rare.
F44.6
Dissociative anaesthesia and sensory loss
Anaesthetic areas of skin not corresponding to dermatomal distribution.
Sensory loss not explained by any neurological lesion; may be accompanied with
paresthesia. Psychogenic deafness.
dissociative (conversion) disorders specified in F44.0-44.6 F44.8 Other dissociative disorders Ganser’s syndrome Multiple personality Psychogenic confusion twilight state F44.9 Dissociative (conversion) 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 dissociative 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.
[edit] 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).
[edit] Measures of Dissociation
Clinician-administered structured interviews, clinician-administered measures, and self-report instruments (Chu et al. 2005).
[edit] 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.
[edit] 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.
[edit] 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
subscales–Disengagement, Depersonalization, Derealization, Emotional
Constriction/Numbing, Memory Disturbance, and Identity Dissociation–and a total dissociation scale (Chu et al. 2005).
[edit] 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).
[edit] 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).
[edit] Other rating scales that are available for use to assess Dissociative
disorders (http://www.neurotransmitter.net/dissociationscales.html)
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 Depersonalization Questionnaire Adolescent MID 6.0 Dissociative Features Profile (DFP)
Textbook of Psychiatry/Dissociative Disorders/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.