The association between seizure clustering and convulsive status epilepticus in patients with intractable complex partial seizures

Purpose: We examined the association between seizure clustering and convuls ive status epilepticus (SE) in patients with intractable complex partial se izures, to identify whether patients whose seizures typically cluster are a t high risk for convulsive SE (CSE). Methods: Seventy-six patients with intractable complex partial epilepsy who underwent presurgical evaluation in the Montefiore Epilepsy Management Uni t from 1993 to 1997 were contacted and interviewed about typical seizure fr equency and distribution and history of CSE. Seizure clustering was defined as three or more complex partial seizures within a 24-h period, with retur n to baseline between seizures. Results: Of the 76 patients contacted, 21 (28%) had experienced at least on e episode of CSE, and 36 (47%) typically experienced clustered seizures. SE occurred in 16 (44%) of 36 patients with clustered seizures, and in five ( 12.5%) of 40 patients with nonclustered seizures (p < 0.002). Of 53 patient s with temporal lobe epilepsy, CSE occurred in 13 (50%) of 26 patients with clustered seizures, and four (14.8%) of 27 patients with nonclustered seiz ures (p < 0.006). Conclusions: Patients with intractable complex partial or localization-rela ted epilepsy who typically experience seizure clustering are at a significa ntly higher risk for CSE than are patients with nonclustered seizures.