Abstracts

Rationale: While depression, dysthymia, and subsyndromic mood disorders are common comorbid conditions in patients with epilepsy, they are often not recognized and, therefore, many patients receive no treatment for their mood symptoms. This is despite the fact that mood disorders have consistently been shown to have a significant impact on health-related quality of life in patients with epilepsy. Our objective was to determine the prevalence of mood disorders in our clinic population and how best to screen for mood disorders.Methods: A program was implemented in our tertiary care clinic to screen for mood disorders utilizing questionnaires administered by nursing staff. Screening consisted of questions regarding a diagnosis of depression and treatment, and risk of suicidality, the Interictal Dysphoric Disorder Inventory (IDDI), the Patient Health Questionnaire (PHQ-9), and the Quality Of Life In Epilepsy (QOLIE-10). A chart review was completed of the first 104 patients who underwent this screening.Results: 100 patients completed the questionnaire and screening. 31 patients (31%) met a definite diagnosis of depression based on the IDDI. 54 patients (54%) patients were at least mildly depressed based on the PHQ-9. No difference in the prevalence of depression was observed for gender, patient age, and family history of depression, seizure freedom over the preceding 4 weeks or employment status. Three patients identified as depressed on the IDDI did not meet criteria for mild depression on the PHQ-9. All of the patients (19) who identified themselves as having current thoughts of suicide were diagnosed as at least mildly depressed on the PHQ-9, however the IDDI did not identify 8 of these patients as being depressed. Quality of life was significantly associated with a diagnosis of mild depression (diagnosis associated with a score of 1.17 greater on the QOLIE-10 compared to non-depressed, CI = 0.85 to 1.49, p<0.0001) as well as having had seizures in the preceding 4 weeks (presence of seizure(s) associated with a score of 0.56 greater on the QOLIE-10 compared to no seizures, CI = 0.21 to 0.91, p<0.002). In those patients for which the information was available (70), review and discussion with the clinic nurse took a mean of 19.6 minutes to complete. In addition, many patients indicated to the nursing staff that they preferred the organization and syntax of the PHQ-9.Conclusions: Depression is a common condition seen in our clinic population. The PHQ-9 is a sensitive means of screening for depression and most importantly, identified all patients with risk of suicidality. Depression and ongoing seizures are both significantly associated with health-related quality of life in patients with epilepsy. Our results suggest that the PHQ-9 could be used as a screening tool to detect clinically significant depressive symptoms in an outpatient epilepsy clinic setting.