Radu V. Saveanu, MD
David P. Kasick, MD
DESCRIPTION
- Conversion disorder is a somatoform disorder defined as a condition characterized by symptoms or deficits affecting voluntary motor or sensory function in which there is a loss or alteration in physical functioning. These symptoms are suggestive of a physical disorder but, following investigation, are not found to have an identifiable medical explanation.
- By definition, the symptoms are not voluntarily produced, and are conceptualized as the physical expression of an underlying psychological conflict.
EPIDEMIOLOGY
Incidence
- The incidence of conversion symptoms varies widely depending on the population being studied; most estimates range from 5–10 per 100,000 in the general population, and 20–120 per 100,000 among hospital inpatients.
- It is estimated that 1–14% of patients treated in psychiatric or neurologic settings have experienced conversion symptoms.
Prevalence
Prevalence estimates are around 40 per 100,000.
RISK FACTORS
- Conversion symptoms are more common in rural areas, and lower socioeconomic groups (less psychologically sophisticated populations). These symptoms are also more common in military personnel exposed to combat situations.
- Age
- Conversion symptoms may present at any age, although onset is rare before age 5 or after age 35. Typically conversion symptoms are first seen in adolescence or early adulthood.
- Sex
- Conversion symptoms are more frequently diagnosed in women, although some authorities suggest that the disorder is probably gender-equal.
Genetics
No clear genetic link has been established.
GENERAL PREVENTION
Reducing or addressing factors that may lead to psychological conflict.
PATHOPHYSIOLOGY
- Recently some studies have indicated that there may be cerebral dysfunction in the motor and limbic regions in patients with conversion disorder. According to this hypothesis, conversion may reflect certain neurophysiologic vulnerabilities in these patients.
- Proposed abnormalities include inhibition of the motor and sensory processing by the prefrontal cortex and anterior cingulate cortex.
ETIOLOGY
- Until recently, historical explanations for conversion symptoms were limited to psychological models suggesting the subconscious conversion of mental distress or conflict into somatic symptoms.
- Now, modern advances in neuroimaging (PET, fMRI) have identified some of the possible correlating structural pathophysiologic changes in conversion patients.
- Psychodynamic conceptualizations include several explanations of conversion phenomenon, with symptoms potentially reflecting:
- An intrapsychic conflict: The patient may experience conflict over an unconscious, unacceptable, sexual, aggressive, or dependency wish. The somatic symptom maintains the unacceptable wish out of awareness and often resolves the conflict by “punishing or not rewarding” the wish (primary gain).
- An interpersonal communication motivated by obtaining gratification from the environment. In this model, patients who have great dependency needs use their conversion symptoms to obtain attention and to influence their environment (secondary gain). The patient's disability and “helplessness” can become powerful tools in controlling friends, family, or physicians.
COMMONLY ASSOCIATED CONDITIONS
- Conversion is probably multidetermined and represents a common pathway for a variety of etiologic factors. High rates of concomitant psychopathology have been found in patients with conversion symptoms. Depression and antisocial personality disorder are the most commonly reported. Patients with dissociative disorders have relatively high rates of conversion symptoms. Hysterical personality features are found in less than half of patients with conversion symptoms.
- A number of studies have found that patients with conversion symptoms also have high rates of medical and neurologic illness. Physical trauma, temporal lobe abnormalities, and multiple sclerosis may predispose to the development of conversion symptoms.
- Analyses of long-term follow-up studies report that <10% of patients initially diagnosed with conversion disorder are later found to have a medical or neurologic condition that explained their initial symptoms.
- The false-positive diagnosis rate may have declined over time due to advances in diagnostic technology. It is extremely important to keep an open mind regarding the possibility of an organic etiology when making a diagnosis of conversion disorder and to seek appropriate consultations in order to rule out an organic etiology.
HISTORY
- Weakness, paralysis, sensory disturbances, pseudoseizures, blindness, deafness, and aphonia are the most frequent complaints.
- Patients often show a puzzling lack of concern about their deficits. This characteristic lack of concern has been termed “la belle indifference.”
- History should include information about the patient's family, work, other possible stressors, as well as the possibility of secondary gain.
PHYSICAL EXAM
- Neurologic abnormalities are inconsistent and often lack a possible anatomic distribution on physical exam.
- Exam findings do not correlate or are out of proportion with other diagnostic findings or possible medical explanations.
DIAGNOSTIC TESTS AND INTERPRETATION
Lab
Initial Lab Tests
Laboratory testing should be considered to rule out an organic etiology. There are no specific tests to diagnose or rule out conversion disorder. Laboratory studies that are inconsistent with the presenting symptom(s) may help with diagnosis of conversion disorder.
Follow-Up & Special Considerations
LP to rule out an infection or a neurologic illness should be considered when appropriate.
Imaging
Initial Approach
A CT scan or MRI of the head or spinal cord should be considered to rule out a lesion in these areas.
Follow-Up & Special Considerations
- An EEG or prolonged EEG monitoring may be helpful in differentiating a true seizure disorder from pseudo seizures.
- Evoked potentials should be considered in the case of conversion blindness.
Diagnostic Procedures/Other
No psychological test can provide a definitive diagnosis of conversion disorder.
DIFFERENTIAL DIAGNOSIS
- The list of differential diagnoses may cover a good portion of a neurologic textbook. Diagnoses that may be more problematic to exclude are as follows:
- The diagnosis of a conversion symptom can be made only when the symptom in question cannot be adequately explained on the basis of a medical condition. What complicates the diagnosis is the fact that conversion symptoms and physical illness frequently coexist.
MEDICATION
First Line
- Medication has not been found to be generally effective for conversion disorder (1)[A].
- Adjunctive treatment of comorbid psychiatric disorders, for example, using antidepressants to treat co-occurring depression or anxiety, may be helpful.
Second Line
- Case reports have outlined the use of narcoanalysis, in which the patient is given amobarbital IV to the point of calm relaxation. The patient, who is in a relaxed state, is encouraged to discuss recent stresses or conflicts (2)[C].
- Amobarbital IV is given at a rate no faster than 50 mg/min. Infusion is continued until drowsiness, slurring of speech, or sustained lateral nystagmus occur. It is very uncommon to need to use 500 mg or more of Amytal.
- Contraindications:
- Precautions:
- Narcoanalysis must be administered with close monitoring for respiratory depression.
- Short acting benzodiazepines have also been recently described in facilitating hypnosis or psychotherapy, possibly due to a more favorable side effect profile (2)[C].
ADDITIONAL TREATMENT
General Measures
Treatment planning should focus on regaining function. Direct confrontation of the patient regarding the psychological nature of the symptom is not recommended. A simple approach of reassurance, relaxation, and suggestion is indicated. Patients are reassured that their symptoms will disappear and are encouraged to discuss any stressful events or feelings that most likely have been on their mind. Education surrounding the mind–body connection may be useful (2)[B].
- Withdrawal of medical and social attention toward the symptoms, while encouraging physical rehabilitation with physical and occupational therapists may be useful for conversion motor and gait disturbances (3)[B].
- Many conversion symptoms are fleeting, may remit by the time of hospital discharge. Prompt resolution is important since a number of studies have shown that there is a direct relationship between duration of conversion symptoms and chronic disability.
Issues for Referral
- Most patients respond to a course of brief supportive psychotherapy. The focus is on developing a solid working alliance in an environment of mutual trust, respect, and acceptance. The aim of this treatment is to help patients explore various areas of conflict or stress and to help them develop better coping mechanisms. The focus generally shifts from the conversion symptoms to the psychological makeup of the individual (2)[C].
- Cognitive behavioral therapy, aimed at focusing on identifying and changing beliefs and thinking patterns linked to the pathologic symptoms, as well as the development of adaptive behaviors at the expense of maladaptive conversion reactions, may also be helpful (2)[C].
Additional Therapies
Hypnotherapy is thought to offer some benefit in patients with acute symptoms, but needs further study. While patients are under hypnosis, it is suggested to them that their symptoms will gradually improve posthypnotically. Patients are also encouraged to discuss areas of conflict or stress. Other psychosocial interventions warrant further study (4)[C].
IN-PATIENT CONSIDERATIONS
Initial Stabilization
Standard of care medical evaluation for the presenting complaint.
Admission Criteria
Admission should be considered to rule out any serious medical condition and when the severity of the conversion disorder prevents patients from caring for themselves.
Discharge Criteria
Recovery of function and ability to care for basic needs and activities of daily living.
FOLLOW-UP RECOMMENDATIONS
Following discharge, patients may be referred to a psychiatrist for individual treatment.
Patient Monitoring
As prognosis is variable, follow-up for their neurologic complaints is warranted until symptoms resolve.
PATIENT EDUCATION
Patients should be educated about the possibility of recurrent symptoms under stress.
PROGNOSIS
- Good prognostic indicators include:
- Acute symptoms (<30 days)
- Fewer symptoms
- Absence of psychiatric comorbid conditions
- An identifiable stressor
- Good premorbid health
- Good intelligence
- Individual prognosis varies widely; although conversion symptoms are often self-limited and remit quickly, relapse is possible. One study found that symptoms relapse within 1 year in 20–25% of patients.
- Aphonia, blindness, and paralysis are associated with a better prognosis than pseudoseizures and conversion tremor.
COMPLICATIONS
Chronic conversion symptoms (>1 year) have a much poorer prognosis and may require long-term psychotherapy.
