Abstracts

Rationale: The prevalence of depression and anxiety disorder in multiple sclerosis (MS) (50%) and epilepsy (30%) is significantly elevated relative to the general population. Yet, little is known regarding the frequency of mood disorder in those individuals with both diagnoses. The goal of this retrospective study was to determine the risk of mood disorder when both epilepsy and MS co-exist the same person.Methods: Retrospective patient chart review from patients followed by our Multiple Sclerosis or Epilepsy subspecialists evaluated between 12/2002 and 4/2013. Eligibility criteria: diagnosis of MS, diagnosis of epilepsy with onset concurrent or following the MS diagnosis, age 18 and older, and presence of an MS lesion which could account for seizures. Individuals with idiopathic epilepsy and other neurological disorders were excluded. The diagnoses of MS and epilepsy were established by the respective subspecialists. Psychiatric diagnoses were determined by a psychiatrist to whom all patients reporting or observed to have mood disturbances were referred. The data collected included: MS subtype, duration of illness, history of disease modifying therapy, epilepsy subtype, epilepsy duration, electroencephalogram (EEG) findings, antiepileptic medication history, seizure frequency, psychiatric diagnosis, psychiatric treatments, and neuroimaging findings. Results: A total of 13 individuals had both MS and epilepsy and met the study s eligibility criteria. Eleven of the 13 patients (85%) were referred to psychiatry due to concerns regarding a mood disorder. All eleven were diagnosed with depression, anxiety disorder, or both. An Axis I diagnosis of mood disorder was found in 11/13 (85%), with depressive disorder in 10/13 (77%), anxiety disorder in 4/13 (31%), and both anxiety and depression in 3.13 (23%). Mood disorder treatment consisted of either a selective serotonin receptor inhibitor (SSRI) in 7/13 (54%), two SSRI s in 2/13 (15%), two antipsychotics in 1/13 (7%), SSRI and benzodiazepine were prescribed in 1/13 (7%), and a benzodiazepine alone in 1/13 (7%). Individuals with either relapsing MS 7/13 (54%) or progressive MS 6/13 (47%) were equally likely to have a mood disorder. Most patients had good seizure control defined as seizure free for greater than one year. A total of 8/13 (61%) required monotherapy; two patients were treated additionally with gabapentin for pain, and two received benzodiazepine for mood related problems. Polytherapy for epilepsy was necessary in three (15%).Conclusions: Patients with comorbid diagnoses of MS and epilepsy are at great risk for depression, anxiety disorder, or both. Such individuals should be screened for mood disorder; and psychiatric treatment initiated when indicated as mood disorder is closely linked to quality of life.