Abstracts

Rationale: Epileptic seizure disorders have become an increased source of conern in Veterans given the relative high exposure to traumatic brain injury. In general, 50% of adults with focal epilepsy are expected to develop treatment-resistant epilepsy, although when seizuers begin after the age of 50, seizure freedom is likely to occur in 70% of patients. The purpose of this study was to examine wheter the frequency of treatment resistant epilepsy was different in veterans and if the cause and age of onset of the seizure disorder played a factor. Methods: Retrospective study of 214 consecutive outpatient veterans followed in the outpatient clinic of the Miami VA Epilepsy Center of Excellence. Data collected from the medial records included: age of onset of epilepsy, cause , seizure type and epilepsy syndrome, response to pharmacotherapy, presence of psychiatric comorbidities (divided into mood disorder, PTSD, polisubstanceabuse, other), antiepileptic regimen and adherence to medical treatment. Results: Among the 214 patients, 88% were males, the mean age range was 52.31 (SD 15.17 ) years. 162 patients (70.3%) had focal epilepsy presenting with complex partial with or without secondarily GTC (generalized tonic clonic) seizures. The remaining patiens had GTC seizures without evidence of focality by clinical semiology and electrographicrecordings.Among those with focal epilepsy 30.3% was caused by TBI. The comorbid conditions in all patients with epilepsy inlcuded mood disorders (53.2%), PTSD (14%), polisubstace abuse (30.2%) and other psychiatric diseases (30%). Among 214 patints; 43 had not been compliant with their AED regimen or had just ben started on one AED. Hence treatment response was not assessed in these patients. Among the remaining 171 patients, treatment-resistant epilepsy defined as a failure to achieve seizure freedom after two or more AED trials was identified in 34 patients (19%). The mean age of onset of seizure free patients was 37.8+-18.1 years old, which did not differ from that of patients with persistent seizures (35.6 +- 18.1 years old). In addition, seizure- freedom was not associated with duration of seizure disorder, cause of epilepsy and the presence of comorbidities. Lack of adherence to medical treatment was high (25%) Conclusions: The frequency of seizure freedom in this cohort of veterans is lower than that of the general population. These findings cannot be accounted by age of onset of the seizure of the seizure disorder or any of the other examined variables