Abstracts

Rationale: With the overall prevalence rate up to 50 %, psychiatric co-morbidities, especially depressive and anxiety disorders, are common in patients with epilepsy. The interictal dysphoric disorder (IDD), defined by Blumer in 2000 and 2004, is an attempt to distinguish the atypical symptomatology of mood disorders in patients with epilepsy. The existence of IDD as a diagnostic entity is debated. Co-morbid mood disorders, especially depressive disorders, are under-diagnosed in patients with epilepsy, and have been associated with lower quality of life, worse seizure control and higher risk of suicidality. The main aim of this study was to identify co-morbid depression, anxiety, and IDD in patients with epilepsy by using self-report screening inventories followed by the mini international neuropsychiatric interview (MINI). A further objective was to specify the correlation between IDD, depression, and anxiety and assess the quality of life in patients with these disorders. Methods: Adult epilepsy patients from the outpatient epilepsy-clinic at Copenhagen University Hospital North Zealand were prospectively included from January 1, 2013. The following self-report inventories were used to screen patients for anxiety (Anxiety Status Scale = ASS), depression (Major Depression Inventory = MDI, Neurological Disorders Depression Inventory for Epilepsy = NDDI-E), IDD (Interictal Dysphoric Disorder Inventory = IDDI), quality of life (Quality Of Life In Epilepsy = QOLIE31, WHO Five well-being index = WHO-5), and side effects of antiepileptic drugs (Liverpool Adverse Events Profile = LAEP). Patients with scores above threshold in ASS, MDI, NDDI-E or IDDI underwent a mini international neuropsychiatric interview (MINI) to assess if depression, anxiety or some other psychiatric disorder could be diagnosed.Results: By May 31, 2013 67 epilepsy patients have returned the self-report inventories. 18 patients (27%) scored above threshold in one or more self-report inventories. 16 of these patients underwent a MINI, and 14 had IDD, depression, anxiety disorder or a combination of these three disorders. Two of the 16 patients undergoing MINI did not fulfill the diagnostic criteria for a psychiatric disorder. 60 % of the patients diagnosed with IDD also fulfilled the criteria for depression. All patients with scores above threshold in the self-report inventories had considerably lower quality of life, lower scores of well-being, and higher scores in adverse reactions to antiepileptic drugs when compared to patients with normal scores. Conclusions: By screening for depression, anxiety, and IDD in our outpatient population, a quarter of the patients scored above threshold. Almost all of these turn out to have either depression, anxiety, IDD or a combination of these disorders. A major part of patients with IDD also fulfills the diagnostic criteria for depression. Depression, anxiety, and IDD are associated with lower quality of life and well-being, and higher reports of adverse reactions to antiepileptic drugs.