Abstracts

Rationale: Data on proconvulsant activity of the selective serotonin reuptake inhibitors (SSRI) are contradictory, some experimental data may also suggest anticonvulsant properties. In addition, fluoxetine was protective in a SUDEP model with DAB/2 mice. We compared electrographic seizure duration (eSD), duration of convulsions, and postictal EEG depression after sGTCS during video-EEG monitoring of the patients treated continuously with SSRIs with their matched controls. Methods: A case-control study was nested within the cohort of 162 patients with focal epilepsies admitted due to presurgical evaluation in Video-EEG monitoring Unit in Innsbruck, Austria, from 01/2006 to 03/2008. Focal complex seizures (FCSs) and sGTCSs of the patients who were treated during monitoring continuously with SSRIs were the cases. The controls were selected from patients with the same seizure type matched to a case according to sex, age (± 5 years), epilepsy etiology (symptomatic or cryptogenic) and type of recording (surface or intracranial EEG). Seizures were matched in order of their appearance during monitoring sessions. Results: We identified 19 CPSs and 16 sGTCSs in 11 patients treated with SSRIs and matched them with same seizure type of 13 control patients. Final analysis of 35 case-control pairs was performed. eSD of the seizures in patients treated with SSRI (median 132 s; 27-1850) lasted significantly longer (p<0.001) then controls eSD (median 85 s; 22-168). eSD of the SGTCS cases (median 126 s; 65-695) were longer (p = 0.015) then eSD of the SGTCSs controls (median 113.5 s; 65-190). Similarly, eSD of the FCSs cases (median 133 s; 27-1877) were longer (p = 0.004) then eSD of the FCSs controls (median 62 s; 22-99). There was no statistical difference between convulsive phase of cases SGTCS (median 66 s; 56-279) and controls SGTCS (median 68 s; 60-126), as well as between difference of the duration of postictal EEG depression after SGTCSs between cases (median 214.5 s; 105-420) and controls (median 219.5 s; 20-407). Conclusions: Our results strongly suggest that SSRIs treatment is associated with prolonged electroencephalographic seizure duration in patients with focal epilepsies.