Psychogenic non-epileptic seizures (PNES) in the context of concurrent epilepsy – making the right diagnosis

Abstract

Epilepsy is a risk factor for the development of psychogenic non-epileptic seizures (PNES) and comorbid epilepsy is recognized as a comorbidity in about 10–30% of patients with PNES. The combination of epileptic and nonepileptic seizures poses a particular diagnostic challenge. In patients with epilepsy, additional PNES may be suspected on the basis of their typical semiology. The possibility of additional PNES should also be considered if seizures fail to respond to antiepileptic drug treatment, in patients with frequent emergency admissions with seizures and in those who develop new types of seizures. The description of semiological details by patients and witnesses can suggest additional PNES. Home video recordings can support an initial diagnosis, however, especially in patients with mixed seizure disorders it is advisable to seek further diagnostic confirmation by capturing all habitual seizure types with video-EEG. The clinical features of PNES associated with epilepsy are similar to those in isolated PNES disorders and include longer duration, fluctuating course, asynchronous movements, pelvic thrusting, side-to-side head or body movement, persistently closed eyes and mouth, ictal crying, recall of ictal experiences and absence of postictal confusion. PNES can also present as syncope-like episodes with unresponsiveness and reduced muscle tone. There is no unique epileptological or brain pathology profile putting patients with epilepsy at risk of additional PNES. However, patients with epilepsy and PNES typically have lower educational achievements and higher levels of psychiatric comorbidities than patients with epilepsy alone. Psychological trauma, including sexual abuse, appears to be a less relevant aetiological factor in patients with mixed seizure disorders than those with isolated PNES, and the gender imbalance (i.e. the greater prevalence in women) is less marked in patients with PNES and additional epilepsy than those with PNES alone. PNES sometimes develop after epilepsy surgery. A diagnosis of ‘known epilepsy’ should never be accepted without (at least brief) critical review. This narrative review summarises clinical, electrophysiological and historical features that can help identify patients with epilepsy and additional PNES.

Increased suicide attempt risk in people with epilepsy in the presence of concurrent psychogenic nonepileptic seizures

“…Our study corroborates these findings and for the first time estimates the magnitude of risk specific to the concurrent presence of PNES. Given the scarcity of studies examining people with concurrent diagnosis,3 6 our findings represent a substantial advancement towards a better understanding of the psychopathology and risk profile associated to this condition.…”

“…20 Confirming the diagnosis of PNES is a long process and a clinical challenge, and misdiagnosis of PNES as epilepsy is common. 21 It is therefore essential to investigate cases where there is a suspicion for coexisting seizure types 6 and to acknowledge diagnostic uncertainty 22 ; failing to do so could lead to underestimation of risk in a population that is already at elevated risk of suicide, 2 and for whom prevention of premature mortality is a top priority. 23 Our study design allowed us to disentangle the individual effect of PNES and that of epileptic seizure disorder on the risk of attempting suicide in people with concurrent diagnosis.…”

“…Limited data and lack of community-level studies on people with concurrent diagnosis of epilepsy and PNES 6 pose considerable challenges towards accurate clinical risk assessment.…”

The assessment of the knowledge and practices of healthcare providers regarding paroxysmal non‐epileptic events (PNES) in children: A cross‐sectional study

“…However, it is well established in the literature that comorbidity between PNEs and epileptic seizures is common, with up to 10%–30% of patients with PNEs also having epileptic seizures 41 . The question “People with PNEs may also have epileptic seizures” is crucial because it stresses the possibility of comorbidity between PNEs and epileptic seizures.…”

Principles for delivering improved care of people with functional seizures: Closing the treatment gap

“…At the patient level FS can be difficult to distinguish from epileptic seizures, particularly for non-experts, leading to diagnostic errors and delays, conflicting treatment advice and anxiety (Jones et al, 2010). In all, 10–30% of patients with FS have a comorbid diagnosis of epilepsy, leading to problems differentiating functional from epileptic seizures in the same person (Liampas et al, 2021). The underlying basis of FS can vary widely between patients, with elements of post-traumatic stress disorder (PTSD), anxiety, dissociation and other factors variably involved, and a single explanation may not be easy to find in any particular case (Brown and Reuber, 2016a, 2016b).…”