Abstracts

Clinical diagnosis of epilepsy remains difficult in elderly. The aim of the present study was to obtain prospective data to justify the use of the electroencephalogram (EEG) in the emergency room when facing with symptoms suggesting epileptic seizure in elderly people.
This prospective observational study was carried out in line with inpatients in five geriatric centres. Full consent from patients/family was obtained before entering in the study. To be included, patients ([gt]70 years old) needed to have clinical signs suggesting epilepsy and no previous epilepsy diagnosis. There were no inclusion/exclusion criteria regarding concomitant diagnoses or treatment. The EEG has to be performed [lt] 3 h after onset of clinical event and confirmed by an expert in the next 24 hours. The primary criterion was the frequency of patients with clinically suspected epilepsy confirmed by expert review.
On thirty-six selected patients, six had normal EEG and atypical clinical signs and were not included. Hence, 30 patients were included . Among these patients, the diagnosis of epileptic seizures (46% generalized, 63 % partials) was confirmed by the expert in 27 patients. The rate of concordance was thus 90.0% with 90% CI of [0.76; 0.97]. From this population two patients were excluded from analysis (EEG performed [gt] 3 h). 25 patients were then included for further analysis (23 female; 2 male, mean age 87 years; 72-103). According to the first EEG reading, 96% of analysed patients showed at least one electrical abnormality : spikes(41%), spike and wave complexes typical (23%) or atypical (41%), all of these abnormalities being focal (41%) or diffuse(64%) , intermittent (27%) or by bursts (9%). Patients could have more than one electrical abnormality. The first expert analysis of EEG confirmed the presence of typical electrical abnormalities (76%) and atypical abnormalities (16%). The [italic]a posteriori[/italic] review all EEGs by the expert showed typical epileptiform abnormalities (20%), atypical epileptiform activities (44%) and non epileptiform abnormalities (32%). One patient had a non-interpretable EEG, but typical epileptic symptoms. Clinical manifestations of seizure were: isolated mental confusion (36%), tonico-clonic seizures (36%), loss of consciousness with fall (32%), loss of contact (20%). Post-ictal confusion was found in 20% of patients and incontinence in 16%. Hyper- or hypotonia, tongue biting, acute psychic signs, focal deficit syndrome, autonomic disturbance, motor automatism (wandering) and chewing were reported in one patient each.
Clinical symptoms and EEG are often atypical in elderly people. EEG performed within the first 3 hours following the onset of a clinical event is a valuable tool to confirm its epileptic nature and may help to initiate or delay an antiepileptic treatment. EEG has to be more easily accessible in emergency units and elederly care structures.
[Supported by: Pfizer]