• psychogenic non-epileptic seizures
• epilepsy
• personality disorder

Psychogenic non-epileptic seizures (PNES), while superficially resembling epileptic seizures, are not accompanied by the abnormal electrical discharges associated with epilepsy and cannot be explained by other medical conditions. Instead they are psychologically determined and, as patients with PNES may be misdiagnosed as having epilepsy, this disorder poses a considerable management problem. The development of a better understanding of the psychiatric characteristics of PNES patients and other risk factors associated with having PNES may not only assist, along with medical investigations, in the correct diagnosis of patients’ attacks, but may also inform effective treatment.

Though personality disorder has been diagnosed in very variable proportions of PNES patients, and research in this area is complicated by the use of different psychiatric classification systems and measures, the most common diagnoses associated with PNES have been borderline, histrionic, avoidant, and antisocial personality disorder.¹ Given that not all PNES patients satisfy formal diagnostic criteria for personality disorder, a different approach to understanding personality pathology is adopted in the paper by Reuber et al in this issue,² who used the dimensional assessment of personality pathology–basic questionnaire (DAPP-BQ) to identify personality profiles in PNES patients. While indicating that PNES patients as a group have greater pathology of personality than people with epilepsy or healthy controls, Reuber et al also found that the PNES patients’ scores on the DAPP-BQ did not form a single profile of personality traits. Instead they identified two large and one much smaller clusters of patients accounting for 84 of their sample of 85 PNES patients. The DAPP-BQ scores of the two larger clusters resembled the characteristics of borderline personality disorder and compulsive personality disorder, respectively. The third cluster of PNES patients had traits resembling the characteristics associated with avoidant personality; this cluster contained only four individuals.

While a diagnosis of personality disorder per se has been considered a poor prognostic factor in people with PNES,¹ Reuber et al’s approach to personality measurement in individuals with PNES offers the opportunity of moving away from the requirement to make a formal diagnosis of personality disorder before considering personality as one of the factors predictive of outcome. Reuber et al report, on the basis of their retrospective data, that those PNES patients with personality traits resembling borderline personality disorder had worse outcome on follow up in terms of seizure freedom than did the cluster with traits resembling compulsive personality disorder, despite the fact that more of the former than of the latter group had received (unspecified) psychiatric treatment. Reuber et al also address the possible use of different psychotherapeutic techniques for patients with different personality profiles. In addition to dialectical behaviour therapy,³ it may be significant in this context that cognitive therapy has also been developed for use with patients with borderline personality disorder.⁴ However, the use of these personality related psychotherapeutic approaches with people who have not received a formal diagnosis of personality disorder but who have PNES and other psychiatric comorbidities¹ requires careful evaluation alongside other cognitive behavioural methods⁵ before clear indications of their specific value and effectiveness with PNES patients can be obtained.