Effect of Epileptiform Discharge Index on Cognitive Impairment in Adult Epilepsy Patients under Different Conditions

Abstract

Objective The study explored the effect of epileptiform discharge index (IED) on cognitive impairment in adult epilepsy patients under different conditions. Methods A total of 50 epilepsy patients treated in our hospital from Jun. 2019 to Dec. 2020 were selected as observation group, and 50 healthy persons in the same period were selected as control group. The time of sleep in Ⅰ-Ⅱ stages, time of sleep in Ⅲ-Ⅳ stages, total sleep time, number of arousal and frequency of sleep phase transition in two groups were compared. IED in patients with epilepsy in waking and sleeping stages were measured and its relationship with Wechsler Intelligence Scale (WAIS-RC) and Wechsler Memory Scale (WMS-RC) scores were analyzed. Results The time of sleep in Ⅰ-Ⅱ stages of observation group was longer than that of control group. The time of sleep in Ⅲ-Ⅳ stages of observation group was significantly shorter than that of control group. The number of arousal and frequency of sleep phase transition in observation group were significantly higher than those in control group. WAIS-RCIQ and WMS-RCMQ of epilepsy patients in sleeping stage with 10%<IED<50% were significantly lower than those with 0%<IED<1% and 1%<IED<10%. WAIS-RCIQ and WMS-RCMQ of the patients in sleeping stage with IED>50% were significantly lower than those with 0%<IED<1% and 1%<IED<10%. WAIS-RCIQ and WMS-RCMQ of epilepsy patients in waking stage with 10%<IED<50% were significantly lower than those with 0%<IED<1% and 1%<IED<10%. WAIS-RCIQ and WMS-RCMQ of the patients in waking stage with IED>50% were significantly lower than those with 0%<IED≤1% and 1%<IED≤10%. During waking and sleeping stages, there was significant difference of WAIS-RCIQ and WMS-RCMQ among the four groups (0%<IED<1%, 1%<IED<10%, 10%<IED<50%, IED>50%). Conclusion Epileptiform discharges could reduce sleep quality and severely affect cognitive function of patients, and 10% might be the lowest threshold of epileptiform discharge affecting cognitive function of patients.