Abstracts

Rationale: Several case reports described epilepsy-derived progressive memory impairment. However, clinical characteristics of cognitive dysfunction and a long-term improvement of memory by antiepileptic medication have not been fully understood.Methods: We investigated a 59-year-old male who presented with forgetfulness including important matters, word finding difficulty, dizziness, and visual hallucination, and diagnosed as having mild cognitive impairment which might be a prodrome of progressive dementia. At the age of 61 years he developed monthly episodes of loss of awareness and memory lapse over several months. His EEG showed epileptiform discharges regional in bilateral frontotemporal areas. Administration of carbamazepine completely suppressed his seizures. Memory function was chronologically evaluated by the Wechsler Memory Scale - Revised (WMS-R). General cognitive function was evaluated by the Hasegawa Dementia Scale - Revised (HDS-R, full score 30 points, cut-off 21 points). No overt seizures occurred during these examinations.Results: When he started having episodes of memory lapse at age 61, he showed a general cognitive decline (HDS-R scores, 16 points). Four months after starting carbamazepine his HDS-R score improved to 23 and subsequently almost stable over 4 years. WMS-R scores were 79-90-80-79-53 (verbal memory - visual memory – general memory - intention/concentration - delayed recall) at age 59, declined to 83-68-75-98-53 at age 61, and improved to 102-91-97-88-90 at age 65.Conclusions: In middle-aged patients, epilepsy can cause progressive memory disturbance resembling to dementia which can be improved by sufficient seizure control by medication. Acceleration of neuronal damage by seizures may underlie cognitive impairment.