Panic attack symptoms differentiate patients with epilepsy from those with psychogenic nonepileptic spells (PNES)

Highlights

• Patients with PNES report more panic attack symptoms during their events.

• Most of the panic attack symptoms were more common in patients with PNES.

• Endorsing four or more panic attack symptoms is sensitive and specific to PNES.

Abstract

Psychogenic nonepileptic spells (PNES) are frequently challenging to differentiate from epileptic seizures. The experience of panic attack symptoms during an event may assist in distinguishing PNES from seizures secondary to epilepsy. A retrospective analysis of 354 patients diagnosed with PNES (N = 224) or with epilepsy (N = 130) investigated the thirteen Diagnostic and Statistical Manual—IV-Text Revision panic attack criteria endorsed by the two groups. We found a statistically higher mean number of symptoms reported by patients with PNES compared with those with epilepsy. In addition, the majority of the panic attack symptoms including heart palpitations, sweating, shortness of breath, choking feeling, chest discomfort, dizziness/unsteadiness, derealization or depersonalization, fear of dying, paresthesias, and chills or hot flashes were significantly more frequent in those with PNES. As patients with PNES frequently have poor clinical outcomes, treatment addressing the anxiety symptomatology may be beneficial.

Introduction

Psychogenic nonepileptic spells (PNES) are behavioral events of psychological origin that resemble seizures caused by epilepsy but are not due to neurological or other medical disorders. It has been estimated that approximately 20 to 30% of patients referred to epilepsy centers have PNES [1], [2], [3]. Patients with PNES have variable but often poor outcomes [4], [5], [6], [7], [8]. The intractability of PNES is likely multifactorial, including an average of 7 years before accurate diagnosis [9], comorbid personality disorders [10], [11], duration of illness [12], history of abuse [13], [14], as well as frequently coexisting depression and anxiety [15].

A 2005 update on treatments for patients with PNES [16] noted that the majority of the literature consisted of class IV reports (case reports or case series) with a limited number of class III reports. Several of the more promising studies [17], [18], [19] employed cognitive–behavioral therapy (CBT) interventions. According to Goldstein et al. [17], CBT views PNES as characterized by a “vicious circle of behavioral, cognitive, affective, physiological and social factors.” What a patient experiences during PNES may include cognitions and emotions along with physiological symptoms, which could be incorporated as part of CBT treatment.

As indicated by Watson and colleagues [20], there is evidence that the subjective PNES experience is different from an epileptic seizure. Yet, there is little evidence in the literature that illuminates the patients' actual experience in PNES. People with epilepsy may have prodromal symptoms of fear, heart palpitations, diaphoresis, shortness of breath [21], paresthesias, nausea, chest discomfort, fear of dying [22], derealization, concerns of losing control, and tremors [23] that are characteristic of a panic attack. Similarly, patients with PNES may report symptoms reflective of a panic attack with their episodes. Vein and colleagues [24] found a group of patients with PNES who endorsed symptoms classic for a panic attack as typical of their paroxysmal event including dyspnea, palpitations, sweating, hot/cold flashes, trembling/shaking, chest pain, dizziness, abdominal distress, feeling of unreality, faintness, paresthesias, as well as fear of going crazy or doing something uncontrolled at a comparable level as another group diagnosed with panic attacks. Because of these similarities, it is not surprising that some patients with epilepsy [25], [26] were initially misdiagnosed as having panic attacks.

The available literature on panic symptoms in PNES is limited. One study [27] consisting of a medical review of patients with PNES found a high proportion of panic attack symptoms in adolescents but not in adults. However, this was a retrospective record review, and the patients were not specifically questioned about symptoms characteristic of a panic attack. Another study [28] assessing a select number of panic attack symptoms found that these were more common in patients with PNES compared with those with epilepsy.

Our study evaluated panic attack symptomatology in patients with PNES and in those with epilepsy. The thirteen criteria for a panic attack from the Diagnostic and Statistical Manual—IV-TR (DSM-IV-TR) [29] including heart palpitations, sweating, shaking, shortness of breath, choking feeling, chest discomfort, stomach distress, feeling dizzy/unsteady, derealization or depersonalization, fear of losing control, fear of dying, paresthesias, and chills or hot flashes were assessed for each patient. It was hypothesized that patients with PNES would report an overall higher number of total panic symptoms compared with those with epilepsy. In addition, we hypothesized that individuals with PNES would endorse a greater number of the majority of the panic attack symptoms. However, it was anticipated that there would be no difference between patients with PNES and those with epilepsy for the shaking and stomach distress symptoms. Increasing our understanding of the actual PNES experience may assist in formulating an individualized treatment plan leading to better outcomes.