Abstracts

Rationale: There is a bidirectional relationship between epilepsy, and depression and anxiety. Depression and anxiety are both under recognized and undertreated in patients with epilepsy. Treatment for depression can be more than 6 months delayed, and by over a year for other mood disorders in an epileptic population. Epileptic patients with depression and anxiety have a poorer prognosis, with reduced efficacy of antiepileptic drugs and epilepsy surgery noted. Approximately 25% of all patients with epilepsy are aged 60 years or older and as the population ages, some predict that half of all newly diagnosed with epilepsy will be older than 65 years by 2020. The negative effects of mood disorders in the general epileptic population has been established. Although the rate of depression decreases to 5% to 10% in older adults living in the community, higher rates of depression have been associated with other conditions such as stroke, cardiovascular disease, Parkinson’s and dementia. Little is known about rates of depression in older adults with epilepsy. Methods: Upon IRB approval, patient data was retrieved retrospectively from the electronic medical record of all patients seen at the Rush Epilepsy Clinic between 2014-2016. Patients aged 60 years and older with a confirmed diagnosis of epilepsy were included. Exclusion criteria included diagnosis of psychogenic non-epileptic spells, cognitive impairment and other conditions that prohibited the patient from completing all screening questionnaires. Demographic data, neuroimaging, electroencephalographic data and clinical data, including scores for NDDI-E and PHQ-GAD - 7 that were administered during the outpatient visit, were obtained as measurements for depression, anxiety and risk for suicide respectively. Results: Seventy-three patients have been thus far identified, (48 were female) all aged over 60 years with a mean age of 66 +/- 7 years. The average duration of epilepsy was 17 +/- 20 years. The median seizure frequency was 1 seizure every year, the majority were on a single antiepileptic drug (AED), nine required three AEDs and 14 required two AEDs. The average score on the NDDI-E was 11+/- 4 (>10 is diagnostic for depression), on the PHQ-GAD-7 was 5 +/- 5 (>15 is diagnostic for anxiety). Fifty-two percent (n=38) scored positive for depression, while only five percent (n=4) scored positive for anxiety. A higher age was not associated with depression (p=0.39), however a longer duration of epilepsy (21+/- 4 years versus 12 +/- 4 years) was associated with depression (p=0.10)(See Figure). Conclusions: Approximately 17%-30% of patients will meet formal criteria for major depressive disorder and 21% of patients with poorly controlled temporal lobe epilepsy will have major anxiety disorder. Higher rates (20-60%) of depression are associated with intractable epilepsy, however our patients were not intractable and had a higher than expected rate of depression (52%) but did not suffer from anxiety (5%). While advanced age in this older cohort was not associated with depression, duration of epilepsy appeared to have an effect. A comparison with a younger cohort will need to be performed to further understand this relationship. In this vulnerable population, however, depression rates appear significantly higher than expected and further study needs to be made to understand the effects and to optimize treatment. Funding: none