Depression in intractable partial epilepsy varies by laterality of focus and surgery.
OBJECTIVE
Depression sometimes occurs after surgical treatment for medically intractable partial epilepsy. The risk of pre- and postsurgical depression may vary by laterality of seizure focus. We reviewed the pre- and postsurgical psychological assessments and clinical courses of patients to identify those at highest risk for postsurgical mood disorders.


METHODS
Depression status was assessed in a consecutive series of epilepsy patients before and 1 year after epilepsy surgery with the use of Scale 2 of the MMPI-2 and a clinical depression index (CDI) scoring the occurrence of depressive symptoms, psychiatric referral, or attempted/completed suicide. Outcome at 1 year was modeled by regression techniques as functions of preoperative mood measurements, side of epilepsy surgery, and preoperative verbal intelligence.


RESULTS
The CDI and Scale 2 MMPI-2 correlated significantly (r = 0.341; p < or = 0.01). Left (n = 54 subjects) and right (n = 53) surgery groups did not differ by sex, seizure outcome, age, education, age at first seizure, duration of epilepsy, or intellect. Higher presurgical depressive morbidity (p = 0.0037) and right-sided surgery (p = 0.0003) predicted higher postoperative CDI. Higher preoperative Scale 2 scores, indicating worse depressive traits, predicted worse postoperative Scale 2 scores (p < 0.0001). Although side of surgery did not predict Scale 2 scores, Scale 2 scores of patients with preoperative right-sided foci tended to have worse postsurgical Scale 2 scores (p = 0.08). Findings for the temporal lobectomy subgroup (n = 90) were similar to those of the overall sample.


CONCLUSIONS
Patients undergoing right hemispheric epilepsy surgery, especially those with high presurgical depression-related morbidity, may be particularly susceptible to clinical depression. Our findings support other studies that show an interhemispheric modulation of depressive traits and symptoms.
Quigg
Mark
M
Department of Neurology, F E Dreifuss Comprehensive Epilepsy Program, University of Virginia, Charlottesville, Virginia 22908, USA. quigg@virginia.edu
Broshek
Donna K
DK
Heidal-Schiltz
Susan
S
Maedgen
Jennifer W
JW
Bertram
Edward H
EH
D000293:Adolescent; D000328:Adult; D015897:Comorbidity; D003866:Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology; D004828:Epilepsies, Partial / Q000175:diagnosis* / Q000523:psychology / Q000601:surgery*; D004827:Epilepsy / Q000175:diagnosis / Q000523:psychology / Q000601:surgery; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008950:MMPI; D008297:Male; D009483:Neuropsychological Tests; D011183:Postoperative Complications / Q000175:diagnosis* / Q000453:epidemiology; D011569:Psychiatric Status Rating Scales; D013405:Suicide / Q000706:statistics & numerical data; D013702:Temporal Lobe / Q000601:surgery*; D016896:Treatment Outcome