Abstract

OBJECTIVE: To investigate changes in depressive and suicidality status and their relationship with seizure outcomes after addition or substitution of another antiseizure medication (ASM) in adults with drug-resistant focal epilepsy. METHODS: 770 consecutively enrolled patients were assessed and followed prospectively for seizure outcome and depressive status over a 6-month period after starting treatment with a newly introduced ASM. The Neurological Disorders Depression Inventory for Epilepsy (NDDIE) was used to screen for depression and suicidality. Correlations of NDDIE results with clinical and treatment-related variables were assessed by using a stepwise logistic regression model. RESULTS: At baseline, 50.0% of patients had a positive screening test result for depression and 13.0% had a positive screening test result for suicidal ideation. A psychiatric comorbidity at baseline was associated with a 2.3 times increased risk of an initially negative NDDIE screening result becoming positive at re-assessment after 6 months. Number of ASMs taken at baseline also correlated with an increased risk of a change in depression screening test results from negative to positive during follow-up, whereas no association was identified with sociodemographic and epilepsy-related variables, including seizure outcomes. Approximately 6% of patients initially negative at screening for suicidal ideation became positive at the 6-month re-assessment. The risk of switch from a negative to a positive screening test result for suicidal ideation was increased more than two-fold in individuals who screened positive for depression at baseline, and was unrelated to type of ASM introduced, sociodemographic variables or seizure outcomes. SIGNIFICANCE: Almost 1 in 5 adults with drug resistant focal epilepsy who screen negative for depression become positive when re-assessed 6 months after a treatment change. 6.1% who screen initially negative for passive suicidal ideation become positive at re-assessment 6 months later. These changes in screening status are independent of type of ASM introduced or seizure outcomes, but correlate with psychiatric status at baseline.