Dual diagnosis of epilepsy and psychogenic nonepileptic seizures: Systematic review and meta-analysis of frequency, correlates, and outcomes

Abstract

Comorbid epilepsy and psychogenic non-epileptic seizures (PNES) represent a serious challenge for the clinicians. However the frequency, associations and outcomes of dual diagnosis of epilepsy and PNES are unclear. The aim of the review was to determine the frequency, correlates and outcomes of a dual diagnosis. A systematic review of all published observational studies (from inception to Dec 2016) was conducted to determine the frequency, correlates and outcomes of dual diagnosis. We included studies of individuals of any age reporting a dual diagnosis of epilepsy and PNES. All observational study designs were included with the exception of case-reports and case series with fewer than 10 participants. The mean frequency of epilepsy in patients with PNES across all studies was 22% (95% confidence intervals [CI] 20 to 25%, range 0 % to 90 %), while the mean frequency of PNES in patients with epilepsy was 12% (95% CI 10 to 14%, range 1% to 62%). High heterogeneity means that these pooled estimates should be viewed with caution. A number of correlates of dual diagnosis were reported. Some studies delineated differences in semiology of seizures in patients with dual diagnosis vs. PNES or epilepsy only. However, most of the correlates were inconclusive. Only a few studies examined outcome in patients with dual diagnosis. Dual diagnosis is common in clinical practice, especially among patients referred to specialized services, and requires careful diagnosis and management.

Management of functional neurological disorder

“…Functional symptoms are quite frequently comorbid with neurological, general medical or psychiatric illness, and thus concurrent sub-specialty management will occasionally be required. For example, a meta-analysis of frequency of dual diagnosis of epilepsy and functional seizures showed that among patients with epilepsy, the frequency of functional seizures was 12%, while among those with functional seizures, the frequency of epilepsy was 22% [7]. Co-morbid psychiatric disorders may require psychiatric intervention [5].…”

“…Patients presenting to memory clinics, found to have no evidence of underlying neurodegenerative or neurological cause for their symptoms, encompass a diverse group with varying aetiologies for their symptoms [31]. A number of common and overlapping clinical profiles have been identified, including: (1) memory symptoms related to depression or anxiety, (2) 'normal' memory lapses that become the focus of attention, (3) health anxiety about dementia, (4) functional memory disorder, (5) memory symptoms as part of another functional disorder, (6) retrograde dissociative amnesia, (7) memory symptoms secondary to medication or drug use, (8) disease other than dementia causing memory symptoms, (9) functional memory symptoms in patients who later go on to develop dementia or another neurologic disease and (10) exaggeration or malingering [31]. Due to this heterogeneity, it is necessary to carefully assess a patient presenting with memory complaints suspected to be functional, specifically attempting to identify an underlying cause such as medical conditions (i.e.…”

Gilles-de-la-Tourette-Syndrom

“…Im Gegenteil, bei manchen GTS-Patienten kann eine plötzliche Zunahme der Intensität der Tics oder eine neuartige Semiologie der Tics auch Ausdruck einer funktionellen Überlagerung sein [57,58]. Als verwandtes Beispiel in der Neurologie seien hier nicht epileptische Anfälle bei Epilepsiepatienten genannt, die sich ebenfalls häufig in ihrer Intensität und Qualität von genuinen Anfällen unterscheiden [59]. Die Abgrenzung von Tics und funktionellen Tic-ähnlichen Bewegungen ist von besonderer Relevanz, da für die erfolgreiche Behandlung funktioneller Bewegungsstörungen ein Schwerpunkt in spezialisierter Physiotherapie und verhaltenstherapeutischen Maßnahmen wichtig ist [60].…”

Functional Cognitive Disorder: Diagnostic Challenges and Future Directions

“…Some individuals may manifest cognitive symptomatology due to a combination of etiological factors, corresponding to the concept of "functional overlay" seen in systematic and functional neurological conditions, whereby core symptoms caused by an underlying structural disease process are complicated by additional functional features [5]. A dual diagnosis of both epilepsy and psychogenic nonepileptic seizures is not uncommon [6], and individuals with chronic conditions such as multiple sclerosis may manifest additional functional symptoms, which can be misattributed [7]. In the context of cognitive symptoms, there are significant challenges around confirming diagnosis, potential for diagnostic evolution over time, and overlapping conditions.…”