Are we overusing the diagnosis of psychogenic non-epileptic events?

Abstract

In order to determine how often results of video/EEG (V-EEG) studies may change the clinical diagnosis of paroxysmal events, we prospectively studied 100 consecutive patients (75 females, 25 males) admitted for diagnosis of recurrent paroxysmal spells. The presumed diagnosis of the referring physician was obtained. Episodes were classified as epileptic seizures (ES), psychogenic non-epileptic events (PNEE), or physiologic non-epileptic events (PhysNEE). Eighty-seven patients had diagnostic events. A final diagnosis of ES was made in 21 patients, PNEE in 39, PNEE + ES in 20, and PhysNEE in seven. All PhysNEE were unsuspected. ES were misdiagnosed as PNEE more frequently than the reverse (57% vs. 12%, P< 0.001). Among the 64 patients with recorded events who had been suspected of having PNEE, 14 (21.9%) were misdiagnosed: two had PhysNEE and 12 (18.75%) had ES. Among the 23 patients with recorded events who were thought to have ES, 12 (39.1%) were misdiagnosed: seven had PNEE, five PhysNEE. V-EEG changed the clinical diagnosis in 29.8% of the patients with recorded events. Our data suggests that clinicians have become more aware of PNEE since the advent of V-EEG and have little problem recognizing them. However, they may be more prone to make a false-positive diagnosis of PNEE in ES with some atypical features. At this point, efforts should be channeled to better training in the proper recognition of ES that mimic PNEE.