Abstracts

Rationale: Although extensive data of paroxysmal non-epileptic events (PNEE) is available in adult patients, less is known of PNEE in the elderly. The purpose of this study was to compare clinical characteristics of PNEE in elderly and non-elderly adult patients. Methods: We retrospectively review data of patients aged 60 years or older admitted to the Epilepsy monitoring unit from January 2005 to December 2009. A control group of adult patients with ages between 20 and 45 years with recorded PNEE was used for comparisons. PNEE were classified as physiological or psychogenic. Psychogenic PNEE were classified as follows: 1) Bilateral motor movements, 2) Focal motor events, 3) Transient unresponsiveness or reduced responsiveness; 4) Predominantly sensory or autonomic events. Physiological PNEE included syncope, sleep disorders, movement disorders, transient ischemic attacks, and migraine headaches. We also reported whether patients were or not taking anti-epileptic drugs (AEDs). Significance levels were set at 5%. A Bonferroni correction was made and significance was identified when p ?.0071. All analysis were conducted using SAS v9.2. Results: In total, PNEE only was recorded in 35 (24.5%) out of 143 patients aged 60 years or older. Mean age of elderly patients was 68.2 7.5 years and mean age of non-elderly patients was 33.3 7.7 years. The age of onset of PNEE was 62.2 11.1 years and 29.6 8.6 years in elderly and non-elderly adults, respectively. In the elderly group, 57.1% were female and in the non-elderly group, 80% were female. No differences (p = 0.132) were found in the type of psychogenic PNEE: 17 (48.6%) elderly and 18 (51.4%) non-elderly patients had bilateral motor movements; 2 (5.7%) elderly and 1 (2.9%) non-elderly patient had focal motor movements, 3 (8.6%) elderly and 10 (28.6%) non-elderly patients had transient unresponsiveness; 5 (14.3%) elderly and 5 (14.3%) non-elderly patients had predominantly sensory or autonomic events. Seven (20%) elderly and 2(5.71%) non-elderly patients had physiological PNEE, including syncope, non-epileptic myoclonus, orthostatic tremors, intoxication, and migraine headache (p = 0.15). We found 26 (74.3%) elderly and 9 (25.7%) non-elderly patients aware and responsive during the PNEE. Significantly (p< .0001) more elderly patients were responsive when compared to non-elderly patients. The estimated percent of elderly patients responsive during the PNEE remained significant (p = 0.0015) after adjustment for gender differences. No differences were found between groups regarding the duration (p = 0.18) or frequency (p = 0.48) of PNEE. Most elderly (74.3%) and non-elderly (71.4%) patients were taking AEDs and no differences (p = 0.78) were found between groups. Conclusions: Elderly patients were more likely to be responsive and following verbal commands properly during the PNEE than non-elderly adult patients. We did not find any other differences in semiology, duration, or frequency of PNEE between these two age groups. More than 70% of elderly and non-elderly patients were taking unnecessary AEDs.