From the Department of Neurology, University of Maryland School of Medicine, Baltimore, MD.
- Objective: To provide a review of psychogenic nonepileptic seizures, including a discussion of the diagnosis, treatment, and clinical significance of the disorder.
- Methods: Review of the relevant literature.
- Results: Psychogenic nonepileptic seizures are a common and potentially disabling neurologic disorder. They are most prevalent in young adults, and more commonly seen in women versus men. Certain psychosocial variables may impact the development of the condition. The diagnosis is made through a detailed history and observation of clinical events in conjunction with video EEG monitoring. Neuropsychological testing is an important component in the evaluation. Treatment includes establishment of an accurate diagnosis, management of any underlying psychiatric diagnoses, and regular follow-up with a neurologist or trained care provider.
- Conclusion: Psychogenic nonepileptic seizures represent a complex interaction between neurologic and psychological factors. Obtaining an accurate diagnosis through the use of video EEG monitoring and clinical observation is an important initial step in treatment and improved quality of life in this patient population.
Psychogenic nonepileptic seizures (PNES) are commonly encountered in outpatient specialty epilepsy clinics as well as inpatient epilepsy monitoring units. They comprise approximately 20% of all refractory seizure disorders referred to specialty epilepsy centers [1–4]. PNES are thought to be psychological in origin as opposed to arising from abnormal electrical discharges as in epileptic seizures. PNES may be more frequent and disabling than epileptic seizures, and patients with PNES may report worse outcomes [5,6]. Increased utilization of long-term video EEG monitoring along with greater recognition of psychogenic neurologic disorders has allowed for improved diagnosis of PNES. However, many diagnostic and therapeutic challenges remain. There are often delays in obtaining an accurate diagnosis, and optimal management remains challenging, often leading to inappropriate, ineffective, and costly treatment, sometimes for many years [6–8].
PNES are seen across the spectrum of age-groups, from children [9,10] to elderly persons, but they most often occur in young adults between the ages of 15 to 35 years [1,8]. Caution should be used when considering this diagnosis in infants or young children, in whom it is more common to see physiologic events that may mimic epileptic seizures, including gastroesophageal reflux, shuddering, night terrors, or breath holding spells [1,9,10].
PNES are prevalent within epilepsy practices. Patients with PNES comprise approximately 5% to 20% patients thought to have intractable epilepsy seen in outpatient centers, and within epilepsy monitoring units they account for 10% to 40% of patients [1,2,6,8]. A population-based study approximates the incidence of PNES at 1.4 per 100,000 people and 3.4 per 100,000 people between the ages of 15 to 24 years .
There is a female preponderance in PNES, which is similar to other conversion and somatoform disorders. Overall, women comprise approximately 70% to 80% of patients with the PNES diagnosis [1,2,6]. There are psychosocial variables that are seen in some patients with this disorder. An important factor that has been described is past history of sexual or physical abuse. In one series, there was a history of sexual abuse in almost 25% of patients with PNES, and history of either sexual abuse, physical abuse, or both in 32% of patients . A history of sexual and/or physical abuse is not exclusive to these patients, and can certainly be seen in patients with epilepsy as well. For example, in a control population of epilepsy patients, there was a reported rate of past sexual or physical abuse approaching 9% .