The Necessity of Video-EEG Monitoring in Older Adults-Part III: Physiologic Nonepileptic Seizures in Later Life
Abstract number :
2.122
Submission category :
Year :
2001
Submission ID :
414
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
K.A. Hirschorn, MD, Neurology, Mayo Clinic, Scottsdale, AZ; D.R. Chabolla, MD, Neurology, Mayo Clinic, Jacksonville, FL; J.J. Bortz, PhD, Psychology, Mayo Clinic, Scottsdale, AZ; J.I. Sirven, MD, Neurology, Mayo Clinic, Scottsdale, AZ
RATIONALE: A number of physiologic events can convincingly mimic seizures in older adults. However, little is known about the degree of overlap of clinical and diagnostic features of Physiologic non-epileptic seizures (PhNES) with epileptic seizures (ES). We describe clinical and diagnostic features of a sample of older adults diagnosed with PhNES via inpatient video-EEG monitoring (v-EEG).
METHODS: Computerized databases were searched for all admissions of patients 60 years and older who underwent v-EEG monitoring between 1995 and 2000 at the Mayo Clinics in Arizona and Florida. Patients determined to have a physiological cause to their symptoms, but not ES or psychogenic seizures, with typical spells captured during v-EEG were included. Patients with v-EEG confirmation of ES documented in this same time frame were included in a comparative analysis.
RESULTS: Of 509 cases monitored, 77 (15%) were age 60 and older (Mean age=70.2, range=60-86 years). Physiologic NES was documented in 17 patients (22%; 10 male, 7 female). Epilepsy was documented in 41 patients (53%), of which 24 were male and 17 were female.
PhNES and ES groups did not differ in average duration of events, mean age, marital status, driving, or incidence of injury (p=NS). Patients with PhNES were as likely to be treated with antiseizure drugs (AED) as those with ES in that an equal number of patients were taking at least one (AED) at the time of evaluation (79%).
The majority of PhNES and ES patients had abnormalities on MRI (65% PhNES, 83% ES, p=NS). In both groups, leucoariosis was the most common finding, occurring in 29% of PhNES and 24% of ES patients. The groups did not differ in the occurrence of v-EEG abnormalities (59% PhNES , 73% ES patients). The majority of PhNES patients had normal outpatient EEGs (41%) compared to 27% of ES patients with negative findings.
Of the 17 PhNES patients, 5 had dizziness and 5 had loss of awareness as the major symptom (29% in each category); 3 had multiple symptoms (18%), and convulsions, tremor/focal movements, falls, and incontinence were reported by one patient in each category (6%, respectively).
Discharge diagnoses of PhNES patients were as follows: TIAs (5) syncope (5); encephalopathy (2); vertigo(1), sleep disorder(1), and tremor(1).
CONCLUSIONS: These findings highlight the difficulty in distinguishing between ES and PhNES in older adults based on clinical grounds alone. There is considerable overlap between diagnostic test results in both PhNES and ES patients with all diagnostic variables failing to differentiate PhNES from ES patients. These data underscore the need for v-EEG monitoring in older patients with recurrent events.