Follow-up Study Of Cognitive Function And Brain Biochemical Metabolism In Patients With Acute Major Depressive Disorder

Objective:To explore the natural course of Major depressive disorder(MDD),and the dynamic changes of cognitive function and brain biochemical metabolic level of patients with MDD.Methods:According to the diagnostic criteria of the American Diagnostic and Statistical Manual of Mental Disorders 5th edition(DSM-5),131 patients with acute MDD(MDD group)were enrolled,and 39 healthy controls(HC group)were recruited.After inclusion,clinical assessment,cognitive function test and ~1H-magnetic resonance spectroscopy(~1H-MRS)scanning were performed for both groups and patients with MDD were followed up for one year,and were evaluated at 3 months,6 months,9months,12 months after baseline.In this study,MARTICS consensus cognitive function test(MCCB)was used to evaluate the cognitive function of participants,and~1H-MRS was used to detect the levels of important brain biochemical metabolites such as N-acetylaspartate(NAA),Choline(Cho)of participants.According to the normality of samples,independent sample T-test and Mann-Whitney U test were used to compare the differences between acute MDD group and HC group,complete remission group and partial remission group during the follow-up period.Paired T-test or Wilcoxon test was used to compare the changes in patients with MDD before and after acute and follow-up stage.Pearson or Spearman analysis was used to analyze the relationship among cognitive function and brain biochemical metabolism in patients with MDD.Results:1.During the one-year follow-up period,a total of 56 MDD patients completed the follow-up evaluation,with a follow-up response rate of 43%.Among them,9 patients had turned mania during the follow-up period,with a manic conversion rate of 16%.7patients fell off during the treatment,with a fall rate of 13%.Among the remaining 49patients with maintenance therapy,36 patients achieved effective treatment,with an effective rate of 64%;22 patients had complete remission,with a remission rate of39%.The manic conversion rate and treatment drop rate at 9 months after baseline were higher than those at other time points,while the effective rate and remission rate were lower than those at other time points.2.The patients with acute MDD performed worse in many cognitive domains and total cognition(p<0.001),such as speed of processing(p<0.001),working memory(p<0.012),verbal learning(p<0.001),visual learning(p<0.001)and social cognition(p<0.001).The Cho/Cr ratio of bilateral putamen was higher than that of HC group.The performance of social cognition of MDD patients was negatively correlated with left putamen Cho/Cr ratio(r=0.368).3.The results of the acute phase and the follow-up period showed that the speed of processing(p=0.018),working memory(p=0.008),visual learning(p=0.022)and other cognitive domains as well as total cognition(p=0.001)were significantly improved in SF3 compared with the baseline period,especially the cognitive domain of working memory.However,there was no significant difference in the level of brain biochemical metabolism between acute period and follow-up period.The performance of speed of processing in patients during follow-up period was positively correlated with the NAA/Cr ratio in the left thalamus(r=0.403).4.There was no significant difference in cognitive function between the complete remission group and the partial remission group during the follow-up period,but in terms of brain biochemical metabolism,the ratio of Cho/Cr in the left cingulate gyrus in the complete remission group was lower than that in the partial remission group(p=0.043),and the ratio of Cho/Cr in the right putamen was higher than that in the complete response group(p=0.026).Conclusion:1.During the follow-up period,patients with acute MDD may have clinical states such as irritability,treatment loss,recurrence,remission and so on.In the course of natural development of MDD,9 months after baseline is the high incidence period of disease fluctuation.Therefore,it is necessary to strengthen the management of the whole course of disease,especially in the consolidation phase.2.Patients with acute MDD have cognitive impairment in several cognitive domains,such as speed of processing,working memory,verbal learning,visual learning,social cognition and so on.The impairment of working memory,visual learning was improved with the remission of depressive symptoms,showing state characteristics.while speed of processing,verbal learning and social cognition show trait characteristics.3.In patients with acute MDD,the phospholipid metabolism in the putamen increased,and the high phospholipid metabolism in the left putamen was associated with the impairment of social cognitive function.The residual cognitive impairment of speed of processing in follow-up period was associated with thalamic neuronal activity.4.Whether the outcome of treatment in the acute phase reached complete remission had no significant effect on the cognitive symptoms of patients,but had an effect on the level of brain biochemical metabolism of patients,which suggested that the level of brain biochemical metabolism of patients might be related to the treatment response.