Effect of drug treatment changes and seizure outcomes on depression and suicidality in adults with drug-resistant focal epilepsy.

Abstract

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. 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. 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. 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.