Psychogenic nonepileptic seizures: clinical characteristics and outcome

Abstract

Background: Clinical characteristics, outpatient situation, and outcome in patients with psychogenic nonepileptic seizures (PNES) remain to be elucidated.

Methods: Patients diagnosed with PNES after video-electroencephalography (EEG) monitoring (VEM) 03/2000-01/2016 at the Erlangen Epilepsy Center were surveyed between June 2016 and February 2017. Primary outcome was PNES cessation defined as no PNES episodes within > = 12 months prior to the interview. Secondary outcome variables included quality of life (QoL) and dependency. Sensitivity analysis included patients with proven PNES during VEM without comorbid epilepsy.

Results: Ninety-nine patients were included (median age 38 (interquartile range (IQR 29-52)) years; 68 (69%) females, follow-up 4 (IQR 2.1-7.7) years). Twenty-eight (28%) patients suffered from comorbid epilepsy. Twenty-five (25%) patients reported PNES cessation. Older age at symptom onset (odds ratio (OR) related to PNES cessation: 0.95 (95% CI 0.90-0.99)), comorbid epilepsy (OR 0.16 (95% CI 0.03-0.83)), anxiety disorder (OR 0.15 (95% CI 0.04-0.61)), and tongue biting (OR 0.22 (95% CI 0.03-0.91)) remained independently associated with ongoing PNES activity after adjustment. Sensitivity analysis (n = 63) revealed depressive disorder (OR 0.03 (95% CI 0.003-0.34)) instead of anxiety as independent predictor, while this seemed relevant only in patients older than 26 years at onset (OR 0.04 (95% CI 0.002-0.78) versus OR 0.21 (95% CI 0.02-1.84) in patients younger than 26 years). PNES cessation was associated with increased median QoL (8 (IQR 7-9) versus 5.5 (IQR 4-7); p < .001) and an increased frequency of financial independency (14 (56%) versus 21 (28%); p = .01).

Conclusions: We found poor outcomes in PNES especially in older patients at onset with comorbid depressive disorder. Comorbid epilepsy also seems to be a major risk factor of ongoing PNES activity, which in turn affects patients' daily living.

Keywords: activities of daily living; mental disorders; nonepileptic seizures; patient-relevant outcome; prognosis.