Abstracts

RATIONALE: Treatment of epilepsy in older adults is increasingly common yet very little is known regarding clinical features of chronic seizures in late life. Thus, we describe demographic, clinical, EEG, MRI and social features of older adults with epilepsy diagnosed by inpatient video-EEG (v-EEG) recording.
METHODS: Computerized databases were searched for all patients 60 years and older who underwent v-EEG recording between 1995 and 2000 at the Mayo Clinics in Florida and Arizona. Only patients with v-EEG confirmed epilepsy were included in the analysis.
RESULTS: Of 509 cases recorded, 77 (15%) were age 60 and older, and 41 (53%) of these were diagnosed with epileptic seizures (ES) (24 males and 17 female; mean age = 70.2, range = 60 to 86 years). Three patients (4%) had a mixture of ES and psychogenic seizures and were not included in this analysis. Forty-three percent of the 77 cases were found to have either physiological or psychological imitators of epilepsy.
The majority of patients had adult-onset epilepsy with a mean duration at v-EEG of 13.7 years. Thirteen continued to drive up to the time diagnosis was confirmed. Minor seizure related injuries occurred in 11 (27%) and major injuries, such as fractures, in 1 (2%). At least one antiepileptic drug was tried in 83% of patients prior to v-EEG.
Outpatient EEGs were abnormal during wakefulness and sleep in 30 (73%) patients with focal epileptiform activity noted in 18 (44%). Only 17% of the patients had a normal MRI. Leukoariosis was the most common finding(10), followed by intraparenchymal tumor (8), cortical or subcortical infarction (6), hippocampal asymmetry (5), subdural hematoma (4), and generalized atrophy (1). No correlations were noted between specific EEG and MRI findings. Only 2 (5%) had both normal EEG and brain MRI before v-EEG referral.
Seizures were clinically characterized by memory loss or loss of consciousness in the vast majority of patients, followed by: focal tremor, dizziness, convulsions and speech changes. The seizures were localizable on EEG to one brain region or lateralized to one hemisphere in 61% of recordings. During v-EEG recording 31 (75%) had focal interictal epileptiform activity. All patients had either abnormal ictal or interictal epileptiform activity.
CONCLUSIONS: Video-EEG recording is an important tool for diagnosing seizures in the older adult. Outpatient EEGs and MRIs were abnormal in most of our patients with epilepsy; however, the outpatient clinical characteristics of seizures were strikingly nonspecific. Such findings highlight the utility of v-EEG monitoring in this population as well as the potential for preventing the serious consequences of under and over-treatment of seizures in older adults.