IS PANIC ATTACK A MASK OF PSYCHOGENIC SEIZURES? A COMPARATIVE ANALYSIS OF PHENOMENOLOGY OF PSYCHOGENIC SEIZURES AND PANIC ATTACKS

The absence of clear clinical criteria for diagnosing psychogenic seizures and the abundance of vegetative symptoms in their structure raise the question of how to differentiate these states from panic attacks (PA). Clinical symptoms of paroxysm were compared in a group of 32 patients with PA and in a group of 15 patients with psychogenic seizures. It was found that the symptoms classified as panic ones according to DSM-III R criteria are equally observed in both groups. These states are differentiated only by the symptom "fear of dying", observed in 20% of patients with psychogenic seizures and in 90% of patients with PA, and by the number of conversion symptoms (5.9 in patients with psychogenic seizures and 2.2 in patients with PA). It is suggested that in both types of paroxysms panic associated symptoms are not specific and these symptoms only reflect affective distress. The latter is specifically expressed in the form of the symptom "fear of dying" during panic attacks and in the form of conversion symptoms during psychogenic seizures.

KEY WORDS: Conversion symptoms, panic attack, psychogenic seizures.

INTRODUCTION

Paroxysmal hysterical states (psychogenic seizures) constitute a relatively amorphous category. There are neither clear positive criteria for diagnosing such paroxysms nor clarity in the terminology of these states. The following terms are usually used: hysterical fits, pseudo-seizures, pseudo-epileptic fits, psychogenic seizures. According to the DSM-III R, third edition, psychogenic seizures are not identified as a separate entity, but conversion symptoms are included in the definitions: "conversion disorders" and "somatization disorders" (1). At thesame time psychogenic seizures account for 20% of the symptoms observed in patients with hysteria (2).

Traditionally, the main criteria for diagnosing psychogenic seizures are motor phenomena (spasms, convulsions) and losses of consciousness. Therefore, psychogenic seizures are usually differentiated from neurological diseases such as epilepsy, syncopes, paroxysmal choreoatetosis, startle-reaction, myoclonal fits etc. Stefanis et al. (3) pointed out the tendency towards a reduction in classical dramatic forms of hysteria in 1976. It was also observed that they may be substituted by minor forms of conversion, mainly on account of vegetative conversion symptoms. Less dramatic fits without expressive motor phenomena and losses of consciousness were also observed by Fenton (4). It is highly probable that psychogenic seizures, accompanied by multiple vegetative disturbances (cardiopulmonary, gastrointestinal and other symptoms) without obvious motor phenomena can "simulate" panic attack (PA).

The question of similarity and difference between psychogenic seizures and PA is poorly discussed in the literature, although "hysterical outburst" within the PA structure (5), "PA with aggression" (6) and focal neurological phenomena in PA (7) have already been described. Attempts have also been made to isolate the paroxysms with neurological conversion symptoms in PA (8). Moreover, Sheehan et al. (9) applied DSM-III R criteria for panic disorders to patients with hysteria and came to the conclusion that in 70% of patients suffering from paroxysmal states, these states can be classified as "panic attacks".

Therefore, the main aim of this study was to perform a comparative analysis of clinical manifestations of psychogenic seizures and PA to investigate the representation of conversion symptoms within the structure of panic attacks and the representation of "panic" symptoms within the structure of psychogenic seizures.

MATERIALS AND METHODS

47 patients with anxiety and/or hysterical paroxysms were examined and treated at the Clinic of the Russian Centre on Autonomic Disorders of Moscow Medical Academy during the period 1988-1991. 32 (6 men and 26 women) patients suffered from PA, their average age was 33.2±1.1 years (range, 23-44 years). There were also 15 patients (1 man and 14 women) with psychogenic seizures whose age varied from 16 to 47 years (average 30.9±2.4 years).

The diagnosis and selection of patients in this study was carried out by researchers at the Centre who had previous experience in the diagnostics and treatment of anxiety and conversion disturbances. The identification of paroxysm as "panic attack" was carried out on the basis of DSM-III R criteria (1). The paroxysm was assessed as psychogenic seizure when it consisted of minor periods of neurological conversion disturbances (mutism, convulsions, spasms, pseudoparesis, losses of consciousness etc.) in combination with vegetative symptoms. This study included only the patients whose paroxysmal states had been assessed identically (not a single discrepancy in diagnostics) by three experienced researchers. The patients who gave rise to doubt, in even one of the experts, as to the type of the paroxysm were excluded from the analysis. None of the patients suffered from organic neurological diseases (excluded as a cause of paroxysmal states).

Each of the patients was requested to mark the symptoms typical of his paroxysm from the given list (Table l) and to range each of the symptoms according to the degree of their expression from 0 to 4 points (0 = not present, 1 = mild, 2 = moderate, 3 = severe, 4 = very severe). The list included symptoms of PA according to DSM-III R classification (group A) and neurological conversion symptoms (group B).

All the results were analysed using methods of variational statistics using confidence intervals of Student's distribution.

RESULTS

Table II summarizes "panic-associated" symptoms and conversion symptoms in two groups of patients in this study. 10 out of 14 "panic symptoms" were encountered in more than 70% of patients with psychogenic seizures. Such symptoms as "dyspnea", "palpitations", "dizziness", "vertigo" or "unsteady feling" exceeded 90%. Among "panic" symptoms the most rare were the "fear of going crazy or doing something uncontrolled during the attack" (7%) or the "fear of dying" (20%). However, 73% of patients with psychogenic seizures reported the "feeling of inner tension". Among the conversion symptoms the most common were by "sight and hearing disturbances" (93%), "pseudoparesis" (80%), "loss of speech and voice" (73%). "Convulsions" were observed in 60% of cases, the "loss of consciousness" in 53% of cases, the "elements of hysteric arc" in 33% of cases.

Of the patients with PA, 10 out of 14 "panic symptoms" were encountered in more than 70%. The most rare symptoms were the "feeling of unreality" (34%) and the "fear of going crazy or doing something uncontrolled during the attack" (31%). There was only one patient with PA who had neither the "fear of dying", nor the "feeling of inner tension". In more than 70% of cases, not a single conversion symptom was encountered. However, in more than 50% of cases patients reported "pseudoparesis" (56%) and "lump in the throat" (50%) and in more than one third of cases they reported "sight and hearing disturbances" (37.5%) and "convulsions" (31%). Not a single patient from this group reported the "loss of consciousness". 8 patients (25%) had 4 or more conversion symptoms during attacks.

The comparative analysis of "panic-associated" symptoms and conversion symptoms in the group of patients with psychogenic seizures and with PA showed the major statistically valuable difference of such symptoms as "the fear of dying" (x²=26.6, p<0.001), "losses of consciousness (x²=23.7, p<0.001), "gait disturbances" (x²=21.1, p<0.001). Other differences concerned only conversion symptoms: "loss of speech and voice" (x²=17.4, p<0.001), "sight and hearing disturbances" (x²=14.3, p<0.001). All the enumerated symptoms except the "fear of dying" prevailed in patients with psychogenic seizures. It was found that the symptoms classified as panic ones according to DSM-III R criteria are equally observed in both groups. These states are differentiated only by the symptom "fear of dying", observed in 20% of patients with psychogenic seizures and in 90% of patients with PA, and by the number of conversion symptoms (5.9 in patients with psychogenic seizures and 2.2 in patientis with PA).

Table III contains the subjective evaluation of the expression of the symptoms in question in patients with psychogenic seizures and PA.

The highest evaluation concerned palpitations and the fear of dying in both groups. There was a significant difference only as regards the "feeling of unreality" which was highly expressed in patients with PA.

DISCUSSION

In our study it was demonstrated that the symptoms classified as panic ones according to DSM-III R criteria are equally observed in a group of 32 patients with PA and in a group of 15 patients with psychogenic seizures. These states are differentiated only by the symptom "fear of dying", observed in 20% of patients with psychogenic seizures and in 90% of patients with PA, and by the number of conversion symptoms (5.9 in patients with psychogenic seizures and 2.2. in patients with PA).

This investigation also proves the complexity of differentiating between psychogenic seizures and PA. As a rule, the doctor does not observe the paroxysm himself, particularly in outpatients. Reporting the paroxysm, the patients usually emphasize vegetative symptoms, whereas abortive paroxysms are often limited to 3-4 vegetative symptoms. On the other hand, in DSM-IIIR criteria for PA it is not stipulated how many additional symptoms and what kind of symptoms there may be in a paroxysm.

The comparison of PA and psychogenic seizure symptoms clinically identified in a similar way showed a considerable overlapping of most symptoms in question. Nowdays there are no criteria that could be considered reliable in differentiating paroxysmal states. Desai et al. (10) suggested the state of unconsciousness as the differential diagnostic symptom to differentiate between psychogenic seizures and PA. However, in our study the "losses of consciousness" are encountered only in 50% of patients with psychogenic seizures. Therefore, it cannot be a sufficient criterion for diagnosing psychogenic seizures. This study showed that the presence of the "fear of dying" in the attack and the number of conversion symptoms make it possible to differentiate these states.

Patients with typical PA reported the presence of 3.15±0.26 conversion symptoms in the attack, whereas separate symptoms, e.g. "pseudoparesis", "a lump in the throat" occurred in half of the patients. Aronson et al. (11) analyzed the symptoms, which are not included in the descriptive DSM-III R criteria for PA and also pointed out the "lump in the throat" and "difficulty of swallowing" in 54.4% of patients with PA. Coyle et al. (2) observed the presence of 2-3 focal neurological symptoms in patients with PA: sensory - "numbness" and "tingling in a hemisensory distribution"; motor - "clumsiness" or "a feeling of heaviness of one or two extremities"; visual - "bilateral blurring or complete blindness". The authors excluded the organic origin of focal neurological symptoms and considered them to be somatic derivatives of hyperventilation. Many researchers observed hyperventilation disorders in the overwhelming majority of PA patients, based on symptoms (12) and on the data of biochemical investigations (13). At the same time they paid considerably less attention to neurological conversion symptoms. This study showed that 4 or more of the conversion symptoms can be observed in 25% of patients with PA.

Hyperventilation is a major mechanism of symptom formation for conversion disorders. Bearing in mind that such hyperventilation symptoms as "dyspnea", "paresthesias" etc. are equally observed in both groups of patients in this study, one can suggest the identical expression of hyperventilation disorders in these groups. However, taking into account that conversion symptoms are more widely represented in the structure of paroxysm in patients with psychogenic seizures than in patients with PA, one can assume the presence of other mechanisms participating in the formation of conversion symptoms in patients with psychogenic seizures. This problem requires further investigation.

The so-called "panic associated" symptoms were observed with the same frequency both in the group of patients with PA and with psychogenic seizures in our study. We speculate that "panic associated" symptoms are probably not specific, but reflect the state of affective distress (general arousal) common to both states. To a certain extent this is confirmed by the high and similar representation of the "feeling of inner tension" in patients with psychogenic seizures and with PA. We suggest that this symptom is an equivalent of affective distress, which is not differentiated by patients. Based on our results, we conclude that in one type of reaction affective distress is probably specifically expressed in panic or "fear of dying" (during PA), in another type of reaction it is expressed in conversion symptoms (during psychogenic seizures).

ACKNOWLEDGMENT

The authors wish to express their appreciation to Dr. Shepeleva I.P. for offering the clinical material.

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