To investigate the clinical and electrophysiological characteristics of patients with sudden unexpected death of epilepsy (SUDEP).
Methods:
Using "epilepsy" as the keyword, the relevant cases entered from October 2011 to March 2012 were searched in the database of the Electroencephalogram (EEG) Monitoring Center, Xijing Hospital, the Air Force Military Medical University. Telephone follow-up was conducted for all confirmed epilepsypatients, and for the death cases confirmed by telephone follow-up, the patients identified as consistent with SUDEPdiagnosis were included in this study based on their past medical history, clinical data, death details, etc, and their clinical and neuroelectrophysiological characteristics were summarized and analyzed.
Results:
Among the 1 232 patientswho underwent 24-hour video-EEGmonitoring during the study period, 354 patients were successfully followed up by telephone interview, of whom 17 patients were died (4.8%), 12 individuals met the diagnosis of SUDEP (7 men, 5 women). The duration of the disease in 9 patients exceeded 10 years. Eight cases presented with focal-bilateral tonic clonic seizures. Nine patients were treated with anti-seizure drug monotherapy. All the 24-hour video EEG of 12 patients were abnormal. There were 8 occasions when the EEG occipital α background rhythm slowed down compared with the standard frequency of peers or was dominated by slow waves. Interictal epileptic discharge (IED) located in temporal lobe were found in 12 EEGrecords, of which 9 EEGrecords were found with frontal IED. One of the 12 cases received 24-hour video EEG twice within 6 years, and his EEG background rhythm was significantly slower and the IED region was expanded compared with the first EEGrecord. At the third year after reexamination of EEG, SUDEP developed in this patient.
Conclusions:
SUDEPpatients have a long course of disease and bilateral tonic-clonic seizure. The interictal EEG shows occipital slow α activity and temporofrontal epileptiform discharges, which may increase the risk of SUDEP.