Seizures exacerbate depressive symptoms in persons with epilepsy

The mechanisms behind comorbid symptoms of depression in persons with epilepsy (PWE) remain largely unknown. Our study aimed to learn whether seizures moderate fluctuations in depressive symptoms in PWE when controlling for preictal symptoms of depression. We enrolled 57 adult PWE admitted to the New York University (NYU) Langone Epilepsy Monitoring Unit (EMU) from 2021 to 2024. Thirty-seven participants had a seizure. Twenty of the admitted patients did not have seizures during the admission period and therefore served as controls. All participants were seizure free for > 7 days prior to participation. Upon admission, all participants completed the Montgomery-Asberg Depression Rating Scale (MADRS) to evaluate baseline mood. The MADRS was repeated acutely (4-24 h post seizure or admission) and subacutely (2-7 days post seizure or discharge) for both groups. Linear regression models revealed that individuals with higher baseline MADRS scores (indicating higher depressive symptoms) experienced worse mood acutely post-seizure, while lower baseline MADRS scores were associated with acute mood improvement (R² = 0.59, p < 0.001). Experiencing a seizure was not associated with subacute mood outcomes, which were instead driven by acute mood state (R² = 0.56, p < 0.001). In conclusion, we found that seizures exacerbate pre-ictal depressive symptoms and that post-ictal depressive symptoms persist up to 7 days after seizure resolution. This study may provide evidence for a bidirectional relationship and demonstrate a vicious cycle between depression and epilepsy.