Clinical Application Of EEG Nonlinear Analysis In Early Diagnosis Of Alzheimer’s Disease

Objective: To investigate the clinical application value of EEGnonlinear analysis in early diagnosis ofAlzheimer’s disease.Method:Mini-mental State Examination(MMSE),Montreal CognitiveAsswssment Scale(MoCA),Global deterioration Scale(GDS),Clinicaldementia rating scale(CDR),Hachinski ischemic index(HIS),Hamiltondepression rating scale(HDRS),activity of daily living(ADL)were completedand EEG were recorded from13mild Alzheimer’s disease patients(MildAD),9amnestic mild cognition impairment patients(aMCI),10vasular cognitiveimpairment patients(VCI) and10normal aged (NA) subjects.Electrodes withsignificance(P＜0.01)were slected to investigate the value of EEG nonlinearanalysis in early diagnosis of Alzheimer’s disease using receiver operatingcharacteristic(ROC)curves.Results:①Nonlinear parameters D2,PD2,Dm,LE,Cx,ApEn,C-ApEn canreflect the overall trend of cognition impairment,in which D2,PD2,Cx,ApEnshowed highly statistical significant differences(P＜0.01);The AD patientshad significantly lower Cx values except at the O2(P＜0.01),lower KE valuesonly at the O1(P＜0.01),and higher values of LE at the O1,O2~electrodes(P＜0.01~,P＜0.05)compared with NA subjects. D2(P4,F7), PD2(P3,T6and thewhole brain mean value),KE(P4,O1),Cx(F7~,T5), ApEn (F7,T4,T6~) weresignificantly lower for aMCI group in contrast to NA subjects(P＜0.01~,P＜0.05). Compared with VCI group,all D2, PD2,Dm,LE,KE,Cx,ApEn,C-ApEn in mildAD group had significant difference(P＜0.05).The LE,KE,Cx,ApEn,C-ApEn values of the EEGs for the aMCI patients were different from thoseof VCI patients(P＜0.05) and significant differences of D2,PD2,Dm,LE,KE,Cx,ApEn,C-ApEn were also found(P＜0.05) when contrastedaMCI patients with mildAD ones.③The diagnosis values of8selectednonlinear parameters are higher at the most electrodes where P＜0.01.Compared with NA group, the diagnosis values of Cx were higher except T5for mildAD. The sensitivity and specificity of LE were69.2%,80%respectively with the moderate diagnosis value only at O2.And84.6%,90%respectively for KE with the moderate diagnosis value only at O1. On theother hand,between aMCI group and NA group, the sensitivity and specificityof Cx were88.9%,70%respectively only at F7with the moderate diagnosisvalue.And77.8%,90%separately for ApEn at T6with the higher diagnosisvalue.Conclusion: Nonlinear analysis of EEG can objectively evaluate thebrain function changes, albeit the sensitivity and specificity for mildAD aresuperior to aMCI, which may contribute to AD early diagnosis.