Effect of subclinical epileptiform discharges on cognitive function in adult epilepsy / 中华神经科杂志

ABSTRACT

Objective To investigate the effect of subclinical epileptiform discharges (SED) on the cognition of adult patients with epilepsy,exploring the mechanism of SED that leads to cognitive impairment in adult patients with epilepsy to raise physicians' attention about SED.Methods Patients were collected in the Department of Neurology,China-Japan Union Hospital of Jilin University from March 2016 to March 2017.Sixty adult patients with epilepsy without clinical episodes in the last three months were selected as SED group and 40 healthy volunteers as control group.Medical history of the SED group was recorded in detail.All patients were examined by Self-rating Anxiety Scale,Self-rating Depression Scale,Pittsburgh Sleep Quality Index scale in order to exclude organic brain disorders,metabolic diseases,anxiety,depression,sleep disorders and drug-induced cognitive dysfunction.Subjects in the two groups received Montreal Cognitive Assessment (MoCA),electroencephalogram and blood oxygen level dependent functional magnetic resonance imaging examination.Finally,the results were compared between the two groups.Results ①SED had different effects on cognitive function in adult patients with epilepsy,and the MoCA score (26(22,27)) showed statistically significant difference compared with the control group (29 (28,29),Z =-6.26,P =0.00).②Different discharges indexes showed different effects on cognitive function aspects.Cognitive impairment was significant when the discharges indexes were ＞ 10％ (discharges indexes 1％-10％MoCA score 26(26,28),discharges indexes 10％-50％MoCA score 22(19.5,25),Z =-4.74,P =0.00).③The cognitive function of epilepsy patients was positively correlated with the duration of education (r =0.41,P =0.00) and the time interval to recent seizure (r =0.31,P =0.02),and negatively correlated with SED (r =-0.57,P=0.17).There was no correlation between cognitive function and duration of disease and onset age.The SED was the main influencing factor of cognitive function in epilepsy.④Compared with healthy people,epilepsy patients with SED showed differences in resting brain function network connection,with strong connective regions at the right inferior temporal gyrus,right hippocampus,bilateral thalamus,with weak connective regions at the double medial upper frontal gyrus,lateral dorsal frontal gyurs.Conclusions SED had an effect on the cognitive function of adult patients with epilepsy.The mechanism of cognitive impairment in adult epilepsy with SED may be related to abnormal brain function in cognitive-related areas.