University of Oxford

Dissociative (Conversion) Disorders

Dissociative (Conversion) Disorders

  • v Introduction and Definitions:

These terms replaced the old concept of hysteria (moving womb). However the term is still used until today even by clinician. It is best avoided as it creates clinical confusion and miscommunication.

The concept is that symptoms of physical illness or certain kind of mental illness have occurred in the absence of physical pathology with which they are normally associated and that the symptoms have been produced unconsciously.

The ICD 10 use the term interchangeably while the DSM-IV uses conversion for physical symptoms and dissociative for mental symptoms.

In the next sections the terms will be used interchangeably (ICD 10) for simplicity

Dissociative disorders can occur as primary disorder or as a feature of another psychiatric (e.g. depression) or organic disorder (temporal lobe epilepsy).

  • v Underlying “Mechanism of Action”:

The psychoanalytical explanation still offers the most plausible explanation for the occurrence of the symptoms of the disorder.

Although the symptoms are not produced deliberately, they present the patients ideas about the illness (i.e. from a personal experience or relative experience)

The symptoms usually confer some advantage to the patient:

  • Primary gain: exclusion from consciousness of anxiety due to psychological conflict. Repression of the i.d.
  • Secondary gain: visible gain such as paralysis in the hand of a person taking care of an elderly. Secondary gain is extremely important to establish diagnoses and it should be reconsidered if it is absent.
  • v Epidemiology:

Prevalence 3-6/1000 .F>M. very rare after 40 (suspect organicity)

  • v Aetiology:

  

•1.      Genetic: not very strong evidence although relatives have slightly higher rate. Twin studies do not support a strong genetic etiology. However somatization appears to be higher in relatives of patient with dissociation.

•2.      Organic: Some organic diseases can present with dissociation, especially if the CNS is involved (left side more than right). Recently huge interest and studies focus on the “organic” factors and possible neurological mechanism.

•3.      Psychological: Generally accepted that this is the immediate cause. The essential feature seems to be the capacity to dissociate i.e disconnects one aspect of psychological function from the rest when the person is subjected to severely stressful events.

•4.      Cultural: there has been decrease over the last decades especially in developed countries. Support for the role of social and cultural factors comes from studies showing that dissociative disorders are common among people from rural areas and lower socioeconomic class.

•5.      Personality:  more common in immature personalities and in personality disorders in general.

  • v Examples of Dissociative (conversion) Disorders:

-Dissociative Amnesia:

Sudden onset. A Person unable to recall long periods of life and may deny any knowledge of their previous life or personal identity.  Some have concurrent organic disease (e.g.  Epilepsy, MS or head injury), these patients with organic disorders may have similar symptoms and may be as suggestible as those without it.

-Dissociative Fugue:

Often occurs after severe stress. There is a loss of memory and wandering away from usual surrounding. When found the individual usually deny all memory of their whereabouts and may deny knowledge of personal identity. Fugue also occurs in epilepsy, severe depression and alcoholism. It may be associated with suicide attempts. Many give a history of severely disturbed relationship with their parents in childhood and others are habitual liars.

-Dissociative Stupor:

The patient is motionless and mute, not responding to stimulation, but aware of their surroundings. It is rare, but excludes schizophrenia, depression, mania and organic brain disorder.

-Ganser’s Syndrome:

Rare, commoner in prisoner, exclude psychosis (functional or organic) consist of four features:

  • 1. Giving ‘approximate answers’ to questions of intellectual function (e.g. 2+2= 5)
  • 2. Psychogenic physical symptoms
  • 3. Hallucinations (? Pseudo hallucinations) usually visual and elaborate.
  • 4. Apparent clouding of consciousness.

-Dissociative Identity Disorder (Multiple Personality Disorder):

Sudden alteration between two patterns of behavior each of which is forgotten by the patient when the other is present. Rare. Many report physical or sexual abuse (up to 95%). Patient often meet the criteria for other diagnoses especially antisocial personality disorders and drug abuse; they also have symptoms of anxiety and depression. Very suggestible.

-Dissociative Trance (Trance and Possession):

Temporary loss of the sense of personal identity and full awareness of the present surrounding. The person acting as if taken over by another personality for a brief period (e.g. religious ritual induced).

-Conversion Disorder:

Psychological cause leading to symptoms or deficit involving voluntary motor or sensory function. Common among people attending doctors. The pattern of symptoms reflects patients’ knowledge and sophistication and influenced by cultural and social factors.

With Motor symptoms:

  • Limb paralysis (psychogenic paralysis)ànot corresponding to nerves distribution, flexion and extension working simultaneously, wasting is absent.
  • Psychogenic disorder of gait (e.g. astasia-abasia)
  • Psychogenic tremor
  • Globus hysterics

 

With Sensory symptoms:

  • Anesthesia
  • Psychogenic blindness, deafness

With seizures and convulsions (Pseudo fits)

  • Distinguish from epilepsy in three ways:

-Does not become unconscious

-No stereotyped movement, incontinence, tongue bite, cyanosis or injury

-EEG normal.

-Interesting Related Syndrome!

Epidemic Hysteria: A dissociative disorder which spread within a group of people as an epidemic, this spread often happens in closed group of young women e.g. schools, nurses home, college resident (e.g. DMC!). Typically the epidemic starts in someone who is highly suggestible, histrionic (centre of attention) or psychotic (rare, refer to previous lectures; shared delusions).

  • v Differential Diagnoses:

Three ways in which physical disease may be wrongly diagnosed as a dissociative disorder.

  • 1. Symptoms may be of physical disease which has not been discovered (e.g. brain CA)
  • 2. Undiscovered brain disease may ‘release’ hysterical symptoms (e.g. TLE)
  • 3. Anxiety caused by the awareness of the early symptoms of physical disease may act as a non-specific stimulus which provokes additional dissociative symptoms such as fugue.

Examples of differential diagnoses:

  • Organic disease of the CNS
  • Parietal complex seizures
  • Histrionic personality(under stress)
  • Malingering.

To minimize error in diagnoses:

  • 1. Usually does not appear after 40
  • 2. Provoked by stress
  • 3. Secondary gain
  • 4. Belle indifference (hysterical indifference): less distress than would be expected of someone with the presenting symptoms.
  • v Prognosis:

Most recover quickly but if longer than one year becomes difficult and last for several years.

  • v Treatment:
  • Resolve stressful circumstances
  • Suggestion
  • Do not encourage behavior
  • Abreaction in extreme cases using hypnoses or IV barbiturate

Reference:

1. Boyle D, Davies S. Psychiatry, Mosby’s crash course 2002.

2. Steple D. Oxford 2.Handbook of Psychiatry, Oxford University Press, 2006

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