Conversion Disorder

Conversion Disorder

Definition

As defined in DSM-IV, conversion disorders are characterized by symptoms or deficits affecting voluntary motor or sensory func-tion that suggest yet are not fully explained by a neurological or other general medical condition or the direct effects of a substance (see Table 54.1). The diagnosis is not made if the presentation is explained as a culturally sanctioned behavior or experience, such as bizarre behaviors resembling a seizure during a religious cer-emony. Symptoms are not intentionally produced or feigned, that is, the person does not consciously contrive a symptom for exter-nal rewards, as in malingering, or for the intrapsychic rewards of assuming the sick role, as in factitious disorder.

Four subtypes with specific examples of symptoms are de-fined: with motor symptom or deficit (e.g., impaired coordination or balance, paralysis or localized weakness, difficulty swallow-ing or lump in throat, aphonia and urinary retention); with sen-sory symptom or deficit (e.g., loss of touch or pain sensation, dou-ble vision, blindness, deafness and hallucinations); with seizures or convulsions; and with mixed presentation (i.e., has symptoms of more than one of the other subtypes). The list of examples is also contained among the pseudoneurological symptoms listed in the diagnostic criteria for somatization disorder. Although deter-mination is highly subjective and of questionable reliability and validity, association with psychological factors is required.

Whereas conversion symptoms are among the most dra-matic symptoms, somatization disorder is characterized by mul-tiple unexplained symptoms in many organ systems; in conver-sion disorder, even a single symptom affecting voluntary motor or sensory function may suffice. Such nosological inconsisten-cies have resulted in a great deal of confusion, both in research and in clinical practice.

The relationship of conversion disorder to the dissociative disorders warrants comment. Long recognized as related, they were subsumed as subtypes of hysterical neurosis in DSM-II: conversion involving voluntary motor and sensory functioning, and dissociation affecting memory and identity. DSM-IV-TR text acknowledges the symptomatic, epidemiological and prob-able pathogenetic similarities between conversion and dissocia-tive symptoms. Such symptoms have been attributed to similar psychological mechanisms, and they often occur in the same in-dividual, sometimes during the same episode of illness. DSM-IV-TR does suggest that patients with conversion disorder be care-fully scrutinized for dissociative symptoms.

Hallucinations are included among the sensory nervous symptoms in DSM-IV. The concept of conversion hallucinations has a long tradition and its inclusion as a conversion symptom was supported by the somatization disorder field trial, in which one-third of a large sample of nonpsychotic women with evi-dence of unexplained somatic complaints reported a history of hallucinations. Among the 40% who had symptoms that met criteria for somatization disorder, more than half reported hal-lucinations. Women with other conversion symptoms were more likely to report hallucinations than were those with no other conversion symptoms.

In general, conversion hallucinations (referred to by some as pseudohallucinations) differ in several ways from those in psy-chotic conditions. Conversion hallucinations typically occur in the absence of other psychotic symptoms, insight that the halluci-nations are not real may be retained, and they often involve more than one sensory modality, whereas hallucinations in psychoses generally involve a single sensory modality, usually auditory. Conversion hallucinations also often have a naive, fantastic, or childish content, as if they are part of a fairy tale, and are de-scribed eagerly, sometimes even provocatively, as an interesting story (e.g., “I was driving downtown and a flying saucer flew over my car and I saw you [the psychiatrist] in a window and I heard your voice calling to me”). They often bear some understandable psychological purpose, although the patient may not be aware of intent. In the example given, the “sighting” was reported at the time that no further sessions were scheduled.

Epidemiology

Vastly different estimates of the incidence and prevalence of conversion disorder have been reported. Much of this differencemay be attributable to methodological differences from study to study, including the changing definition of conversion disorder, ascertainment procedures and populations studied. General pop-ulation estimates have generally been derived indirectly, extrapo-lating from clinic or hospital samples.

Conversion symptoms themselves may be common; it was reported that 25% of normal postpartum and medically ill women had a history of conversion symptoms at some time dur-ing their life (Cloninger, 1993), yet in some instances, there may have been no resulting clinically significant distress or impair-ment. Lifetime prevalence rates of treated conversion symptoms in general populations are much more modest, ranging from 11 to 500 per 100 000 (see Table 54.1). About 5 to 24% of psychiatric outpatients, 5 to 14% of general hospital patients and 1 to 3% of outpatient psychiatric referrals reported a history of conversion symptoms, although their current treatment was not necessar-ily for conversion symptoms. A rate of nearly 4% of outpatient neurological referrals and 1% of neurological admissions (Ziegler and Paul, 1954) involved conversion disorder. In virtually all studies, an excess (to the extent of 2:1 to 10:1) of women reported conversion symptoms relative to men. In part, this may relate to the simple fact that women seek medical evaluation more often than men do, but it is unlikely that this fully accounts for the sex difference. There is a predilection for lower socioeconomic status; less educated, less psychologically sophisticated and ru-ral populations are overrepresented. Consistent with this, higher rates (nearly 10%) of outpatient psychiatric referrals are for con-version symptoms in “developing” countries. As countries de-velop, there may be a declining incidence in time, which may relate to increasing levels of education, and medical and psycho-logical sophistication.

Etiology and Pathophysiology

The term conversion implies etiology because it is derived from hypothesized mechanism of converting psychological conflicts into somatic symptoms, often symbolically (e.g., repressed rage is converted into paralysis of an arm that could be used to strike). A number of psychological factors have been promoted as part of such an etiological process, but evidence for their essential involvement is scanty at best. Theoretically, anxiety is reduced by keeping an internal conflict or need out of awareness by sym-bolic expression of an unconscious wish as a conversion symp-tom (primary gain). However, individuals with active conversion symptoms often continue to show marked anxiety, especially on psychological tests. Symbolism is infrequently evident, and its evaluation involves highly inferential and unreliable judgments. Overinterpretation of symbolism in persons with occult medi-cal disorder may contribute to misdiagnosis. Secondary gain, whereby conversion symptoms allow avoidance of noxious ac-tivities or the procurement of otherwise unavailable support, may also occur in persons with medical conditions, who may take advantage of such benefits.

Individuals with conversion disorder may show a lack of concern out of keeping with the nature or implications of the symptom (the so-called la belle indifférence). However, indifference to symptoms is not invariably present in conversion disorder and is also seen in individuals with general medical con-ditions, on the basis of denial or stoicism. Conversion symptoms may present in a dramatic or histrionic fashion and may be highly suggestible. A dramatic presentation is also seen in distressed individuals with medical conditions. Even symptoms based on an underlying medical condition may respond to suggestion, at leasttemporarily. In many instances, preexisting personality disorders (in particular histrionic personality disorder) are evident and may predispose to conversion disorder. Persons with conversion dis-order may often have a history of disturbed sexuality many (one-third) report a history of sexual abuse, especially incestuous.

If not directly etiological, many psychosocial factors have been suggested as predisposing to conversion disorder. At a minimum, many persons with conversion disorder are in cha-otic domestic and occupational situations. As previously men-tioned, individuals from rural backgrounds and those who are psychologically and medically unsophisticated appear to be pre-disposed, as are those with existing neurological disorders. In the last case, a tendency to conversion symptoms has been attrib-uted to “modeling”, that is, patients with neurological disorders are likely to have observed in others, as well as in themselves, various neurological symptoms, which they then may simulate as conversion symptoms.

Available data suggest a genetic contribution. Conver-sion symptoms are more frequent in relatives of individuals with conversion disorder. In a nonblinded study, rates of conversion disorder were found to be elevated tenfold in female (fivefold in male) relatives of patients with conversion disorder. Nongenetic familial factors, particularly incestuous childhood sexual abuse, may also be involved in some. Nearly one-third of individuals with medically unexplained seizures reported childhood sex-ual abuse, compared with less than 10% of those with complex partial epilepsy.

Diagnosis and Differential Diagnosis

As shown in Figure 54.1, the first consideration is whether the conversion symptoms are explained on the basis of a general medical condition. Because conversion symptoms by definition affect voluntary motor or sensory function (thus pseudoneuro-logical), neurological conditions are usually suggested, but other general medical conditions may be implicated as well. Neurolo-gists are generally first consulted by primary care physicians for conversion symptoms; psychiatrists become involved only after neurological or general medical conditions have been reasonably excluded. Nonetheless, psychiatrists should have a good appre-ciation of the process of making such exclusions. More than 13% of actual neurological cases are diagnosed as functional before the elucidation of a neurological illness (Perkin, 1989). Even after referral, vigilance for an emerging general medical condi-tion should continue. A significant percentage – 21 to 50% – of patients diagnosed with conversion symptoms are found to have neurological illness on follow-up.

Apparent conversion symptoms mandate a thorough eval-uation for possible underlying physical explanation. This evalua-tion must include a thorough medical history; physical (especially neurological) examination; and radiographical, blood, urine and other tests as clinically indicated. Reliance should not be placed on determination of whether psychological factors explain the symptom. Such determinations are unreliable except, perhaps, in cases in which there is a clear and immediate temporal rela-tionship between a psychosocial stressor and the symptom, or in cases in which similar situations led to conversion symptoms in the past. A history of previous conversion or other unexplained symptoms, particularly if somatization disorder is diagnosable, lessens the probability that an occult medical condition will be identified. Although conversion symptoms may occur at any age, symptoms are most often first manifested in late adolescence or early adulthood. Conversion symptoms first occurring in middle age or later should increase suspicion of an occult physical illness.

Symptoms of many neurological illnesses may appear in-consistent with known neurophysiological or neuropathological processes, suggesting conversion and posing diagnostic prob-lems. These illnesses include multiple sclerosis, in which blind-ness due to optic neuritis may initially present with normal fundi; myasthenia gravis, periodic paralysis, myoglobinuric myopathy, polymyositis and other acquired myopathies, in which marked weakness in the presence of normal deep tendon reflexes may occur; and Guillain–Barré syndrome, in which early extremity weakness may be inconsistent.

Complicating diagnosis is the fact that physical illness and conversion or other apparent psychiatric overlay are not mutually exclusive. Patients with physical illnesses that are incapacitating and frightening may appear to be exaggerating symptoms. Also, patients with actual neurological illness will also have “pseudo” symptoms. For example, patients with actual seizures may have pseudoseizures as well. Considering these observations, psychia-trists should avoid a rash and hasty diagnosis of conversion disor-der when faced with symptoms that are difficult to interpret.

As with the other somatoform disorders, symptoms of conversion disorder are not intentionally produced, in distinc-tion to malingering or factitious disorder. To a large part, this determination is based on assessment of the motivation for exter-nal rewards (as in malingering) or for the assumption of the sick role (as in factitious disorder). The setting is often an important consideration. For example, conversion-like symptoms are fre-quent in military or forensic settings, in which obvious potential rewards make malingering a serious consideration.

A diagnosis of conversion disorder should not be made if a conversion symptom is fully accounted for by a mood disorder or by schizophrenia (e.g., disordered motility as part of a cata-tonic syndrome of a psychotic mood disorder or schizophrenia). If the symptom is a hallucination, it must be remembered that the descriptors differentiating conversion from psychotic hallu-cinations should be seen only as rules of thumb. Differentiation should be based on a comprehensive assessment of the illness. In the case of hallucinations, post traumatic stress disorder and dis-sociative identity disorder (multiple personality disorder) must also be excluded. If the conversion symptom cannot be fully ac-counted for by the other psychiatric illness, conversion disorder should be diagnosed in addition to the other disorder if it meets criteria (e.g., an episode of unexplained blindness in a patient with a major depressive episode). In hypochondriasis, neurologi-cal illness may be feared (“I have strange feelings in my head; it must be a brain tumor”), but the focus here is on preoccupation with fear of having the illness rather than on the symptom itself as in conversion disorder.

By definition, if symptoms are limited to sexual dysfunc-tion or pain, conversion disorder is not diagnosed. Criteria for so-matization disorder require multiple symptoms in multiple organ systems and functions, including symptoms affecting motor or sensory function (conversion symptoms) or memory or identity (dissociative symptoms). Thus, it would be superfluous to make an additional diagnosis of conversion disorder in the context of a somatization disorder.

A last consideration is whether the symptom is a culturally sanctioned behavior or experience. Conversion disorder should not be diagnosed if symptoms are clearly sanctioned or even ex-pected, are appropriate to the sociocultural context, and are not associated with distress or impairment. Seizure-like episodes, such as those that occur in conjunction with certain religious ceremonies, and culturally expected responses, such as women “swooning” in response to excitement in Victorian times, qualify as examples of these symptoms.

Course, Natural History and Prognosis

Age at onset is typically from late childhood to early adulthood. Onset is rare before the age of 10 years and after 35 years, but cases with an onset as late as the ninth decade have been reported. The likelihood of a neurological or other medical condition is increased when the age at onset is in middle or late life. Develop-ment is generally acute, but symptoms may develop gradually as well. The course of individual conversion symptoms is generally short; half to nearly all symptoms remit by the time of hospital discharge. However, symptoms relapse within 1 year in one-fifth to one-fourth of patients. Typically, one symptom is present in a single episode, but multiple symptoms are generally involved longitudinally. Factors associated with good prognosis include acute onset, clearly identifiable precipitants, a short interval be-tween onset and institution of treatment, and good intelligence. Conversion blindness, aphonia and paralysis are associated with relatively good prognosis, whereas patients with seizures and tremor do more poorly. Some patients diagnosed initially with conversion disorder will have a presentation that meets criteria for somatization disorder when they are observed longitudinally.

Individual conversion symptoms are generally self-limited and do not lead to physical changes or disabilities. Rarely, physi-cal sequelae such as atrophy may occur. Marital and occupational problems are not as frequent in patients with conversion disorder as they are in those with somatization disorder.

Treatment

Reports of the treatment of conversion disorder date from those of Charcot, which generally involved symptom removal by sug-gestion or hypnosis. Breuer and Freud, using such psychoana-lytic techniques as free association and abreaction of repressed affects, had more ambitious objectives in their treatment of Anna O, including the resolution of unconscious conflicts. To date, whereas some recommend long-term, intensive, insight-oriented psychodynamic psychotherapy in pursuit of such goals, most psychiatrists advocate a more pragmatic approach, espe-cially for acute cases.

Therapeutic approaches vary according to whether the conversion symptom is acute or chronic. Whichever the case, di-rect confrontation is not recommended. Such a communication may cause a patient to feel even more isolated. An undiscovered physical illness may also underlie the presentation.

In acute cases, the most frequent initial aim is removal of the symptom. The pressure behind accomplishing this de-pends on the distress and disability associated with the symptom (Ford, 1995). If the patient is not in great distress and the need to regain function is not immediate, a conservative approach of re-assurance, relaxation and suggestion is recommended. With this technique, the patient is reassured that on the basis of evaluation the symptom will disappear completely and, in fact, is already be-ginning to do so. The patient can then be encouraged to ventilate about recent events and feelings, without any causal relationships being suggested. This is in contrast to attempts at abreaction, by which repressed material, particularly regarding a painful experience or a conflict, is brought back to consciousness.

If symptoms do not resolve with such conservative ap-proaches, a number of other techniques for symptom resolu-tion may be instituted. It does appear that prompt resolution of conversion symptoms is important because the duration of con-version symptoms is associated with a greater risk of recurrence and chronic disability. The other techniques include narcoanalysis (e.g., amobarbital interview), hypnosis and behavioral therapy. In narcoanalysis, amobarbital or another sedative–hypnotic medi-cation such as lorazepam is given intravenously to the point of drowsiness. Sometimes this is followed by administration of a stimulant medication, such as methamphetamine. The patient is then encouraged to discuss stressors and conflicts. This tech-nique may be effective acutely, leading to at least temporary symptom relief as well as expansion of the information known about the patient. This technique has not been shown to be especially effective with more chronic conversion symptoms. In hypnotherapy, symptoms may be removed with the suggestion that the symptoms will gradually improve posthypnotically. Infor-mation regarding stressors and conflicts may be explored as well. Formal behavioral therapy, including relaxation training and even aversive therapy, has been proposed and reported by some to be ef-fective. In addition, simply manipulating the environment to inter-rupt reinforcement of the conversion symptom is recommended.

Anecdotally, somatic treatments including phenothiazines, lithium and electroconvulsive therapy have been reported effec-tive. However, in many cases, this may be attributable to sim-ple suggestion. In other cases, resolution of another psychiatric disorder, such as a psychotic disorder or a mood disorder, may have led to the symptom’s removal. It should be evident from the preceding discussion that in acute conversion disorders, it may be not the particular technique but the influence of suggestion that is specifically associated with symptom relief. It is likely that in various rituals, such as exorcism and other religious ceremonies, immediate “cures” are based on suggestion. Suggestion seems to play a major role in the resolution of “mass hysteria”, in which a group of individuals who believe that they have been exposed to some noxious influence such as a “toxin” or even a “spell” expe-rience similar symptoms that do not appear to have any organic basis. Often, the epidemic can be contained if affected individu-als are segregated. Simple announcements that no such factor has been identified and that symptoms experienced by the group have been linked to mass hysteria have been effective.

Thus far, this discussion has centered on acute treatment primarily for symptom removal. Longer-term approaches include strategies previously discussed for somatization disorder – a pragmatic, conservative approach involving support and explo-ration of various conflict areas, particularly of interpersonal re-lationships. A certain degree of insight may be attained, at least in terms of appreciating relationships between various conflicts and stressors and the development of symptoms. Others advocate long-term, intensive, insight-oriented dynamic psychotherapy.