The Therapeutic Mechanism Of Electromagnetic Convulsion Therapy In Schizophrenia

[Background & Objectives] To date,the repeated reevaluation results of electroconvulsive therapy(ECT)still affirm that it is an effective method for the treatment of schizophrenia(SZ).Magnetic convulsive therapy(MST)has the same effect and little cognitive impairment and is well known.The purpose of this study is as follows: 1.By brain-derived neurotrophic factor(BDNF)and substructure of hippocampus to investigate neural plasticity mechanism of electromagnetic convulsive treatment in SZ;2.Comparison of the differences of ECT/MST in the treatment of SZ with clinical assessment and cognitive function assessment;3.To look for clinical,cognitive and biological indicators to predict the efficacy of ECT/MST in the treatment of SZ.[Methods] Diagnostic criteria for psychiatric diagnosis and Statistics(DSM-IV)diagnostic criteria for schizophrenia.The clinical symptoms were evaluated by positive and negative symptom scale(PANSS).The Repeatable Battery for repeated the Assessment of Neuropsychological Status(RBANS)were used to evaluate cognitive function,blood samples were collected,and brain structural imaging was scanned.According to the research purpose,the research is divided into two parts.The first part studies the relationship between the efficacy and BDNF in SZ patients with ECT.The second part uses brain-derived neurotrophic factor(BDNF)and hippocampal substructure to investigate neural plasticity mechanism of electromagnetic convulsive treatment in SZ,construction of clinical effect prediction model by Logistic regression,comparison of the differences between ECT and MST from four aspects of clinical,cognitive,hippocampal substructure and BDNF.[Results] The first part studies 160 cases of schizophrenia patients and 77 healthy controls.There was no correlation between patients' Positive and Negative Syndrome Scale(PANSS)score and serum BDNF level before ECT;however,a negative correlation was observed after ECT(total: r =-0.692;P < 0.01).From baseline to remission after ECT,serum BDNF level increased(P < 0.001)and their PANSS score decreased(P < 0.001).Changes in BDNF(2.21 ± 4.10 ng/ml)and PANSS score(28.69 ± 14.96)were positively correlated in the ECT group(r = 0.630;P < 0.01).In the second part we studied 51 cases of schizophrenia patients.There was correlation between patients' baseline BDNF levels and hippocampal substructure volume.This correlation was enhanced in the response group.Changes in BDNF levels and hippocampal substructure volume were correlated in the patients.There were 33 cases in ECT group and 18 cases in MST group,and the difference in hippocampal substructure volume between the two groups was compared by t test.Using the factor analysis to reduce the 24 hippocampal subfields to seven common factors.And then the main effects of clinical group on hippocampal subfields in units of the seven common factors were observed by multivariate analysis of variance(ANOVA).Thus the right_CA4,right_GC-ML-DG,left_molecular_layer_HP,left_CA1,and left_subiculum were selected as regions of interest(ROI),and the right_CA4 ? right_GC-ML-DG and left_molecular_layer_HP finally entered into Logistic regression model ?(?=12.395 P=0.030).On the basis of the above 3 prediction factors,the clinical symptoms(baseline PANSS total score),RBANS(baseline Attention score)and hematological index(baseline M/P ratio)entered into Logistic regression model ?(?=17.255 P=0.008),improving the predictive efficacy of the model significantly.ECT is superior to MST in the treatment of positive symptoms of schizophrenia,but according to the analysis of effective rate and PANSS reduction rate,it is found that there is no significant difference in the overall efficacy of ECT and MST.The total score of RBANS in ECT group was significantly decreased,while the total score of RBANS was not significantly changed before and after MST intervention.ECT group in the left hippocampus(subiculum,CA1,molecular_layer_HP,GC-ML-DG,CA3,CA4,HATA)and the right hippocampus(tail,molecular_layer_HP,GC-ML-DG,CA3,CA4,HATA)volume increased significantly than that of MST and there is significant difference.After intervention,plasma BDNF level was significantly increased,while proBDNF level was significantly decreased,M/P ratio increased significantly,but proBDNF in ECT group was decreased significantly than MST group.[Conclusion] 1.The neuroplasticity hypothesis of electromagnetic convulsion therapy for the treatment of SZ-the clinical effect is achieved by increasing the level of BDNF and then increasing the volume of the substructure of the hippocampus.2.the hippocampal substructure volume can be used as a predictor of the efficacy of electromagnetic convulsions in the treatment of SZ.3.ECT and MST were similar in clinical efficacy,and MST intervention did not affect neurocognitive function.The increase in the volume of substructure of hippocampus in ECT group was more obvious,and the decrease of plasma proBDNF level was more significant.