Comorbid impulsivity after one year of epilepsy surgery

Psychiatric comorbidities in patients with drug-resistant epilepsy (DRE) are frequently observed before and after epilepsy surgery. Impulsivity, defined as behaviors that are poorly conceived, are also frequent among patients with epilepsy. The aim of this study was to determine the presence of comorbid impulsivity in patients with DRE after one year of epilepsy surgery.

Patients who underwent epilepsy surgery for DRE and completed the postsurgical assessment protocol one year after surgery were included. All patients underwent a presurgical protocol comprising of neurological, psychiatric, neuropsychological, video-EEG and MRI assessments. The psychiatric evaluation was performed before and one year after surgery using SCID-I, SCID-II, GAF scale of DSM IV, and Beck Depression Inventory II. One year after surgery, Barratt Impulsiveness Scale 11, and Engel classification of seizures, were administered.

A total of 38 patients were included in this study, 21 women (55.3%) and 17 men (44.7%), mean age 36 years (SD = 9.4). Higher impulsivity was associated with a worse epilepsy seizure outcome (p < 0.05), one year after surgery. According to the multiple linear regression analysis, a worse epilepsy seizure outcome was associated with higher levels of nonplanning impulsivity (p < 0.05) (p < 0.05, β -0.5, r² 0.25). The GAF score was negatively associated with motor score (p < 0.05, β -0.584, r² 0.42) and with the total BIS-11 score (p < 0.05, β -0.557, r² 0.39).

Impulsivity has been associated with a worse post-surgical seizure outcome. Larger studies about impulsivity might confirm these preliminary findings.