Clinical Significance Of Anhedonia And Psychomotor Retardation In Major Depressive Disorder

Objective: To explore the significance of anhedonia and psychomotor retardation in the diagnosis of melancholic major depressive disorder(m MDD)subtypes and the antidepressant of fluvoxamine treatment.Method: This study recruited sixty-seven patients with MDD(major depressive disorder,MDD)and thirty-six Healthy Controls(HC).After completing baseline clinical evaluation,blood sample collection,and resting-state functional magnetic resonance imaging,all enrolled MDD patients received monotherapy with fluvoxamine.After two months of treatment,this study recollected clinical symptoms,blood samples,and resting-state functional magnetic resonance imaging of MDD patients.This study used the "2&5/9" standard established by psychiatrists based on previous studies to label the enrolled MDD as m MDD and non-melancholic MDD(nm MDD).The "2&5/9" standard requires the m MDD to meet both anhedonia and psychomotor retardation and 5 or more of the other 9 symptoms.This study used the Snythe Hamilton Pleasure Scale to assess the degree of anhedonia,the Stroop-color test and Trail Making Test A to assess psychomotor speed.This study detected plasma interleukin-6(IL-6)levels in all enrolled subjects;IL-6 is one of the most consistent inflammatory factors with evidence of correlation with anhedonia and psychomotor retardation.This study identified symptom-related regions of interest(ROI)based on imaging research evidence of anhedonia and psychomotor retardation.This study used DPABI software to preprocess structural and functional resting state magnetic resonance imaging data,extracting whole brain functional connections related to symptoms and functional connections between ROIs.Finally,this study summarized the clinical evaluation,biological,and imaging indicators of anhedonia and psychomotor retardation.Finally,this study used support vector machine algorithms on MATLAB(1)based on the baseline values in the clinical evaluation,biological,and imaging indicators of anhedonia and psychomotor retardation,as well as the changes in baseline values and two-month follow-up,predictive models for m MDD subtype diagnosis were constructed;(2)based on the baseline values in the clinical evaluation,biological,and imaging indicators of anhedonia and psychomotor retardation,as well as the changes in baseline values and two-month follow-up,predictive models for the antidepressant efficacy of fluvoxamine were constructed.Result: A total of sixty-four baseline MDD patients,thirty-two HC patients,and forty-seven MDD patients who completed fluvoxamine monotherapy for two months were included in the analysis.Clinical data analysis: The HAM-D17(p<0.001),HAM-A(p<0.001),and SHAPS(p<0.001)of MDD were significantly higher than those of HC,while the psychomotor speed of MDD was significantly lower than that of HC(p<0.001).The psychomotor speed of the m MDD is lower than that of the nm MDD(p=0.030).There is no difference between m MDD and nm MDD subtypes in the two-month antidepressant efficacy of fluvoxamine(△2M-HAM-D17:p=0.367;△2M-QIDS-SR:p=0.144).Biological indicators analysis: There was no significant difference in baseline IL-6 levels between the m MDD and the nm MDD subtype(p=0.909).Imaging data analysis: 1.The whole-brain functional connections related to anhedonia were mainly in the left ventral prefrontal cortex,and the whole-brain functional connections related to psychomotor speed were mainly in the caudate nucleus,putamen and thalamus.2.The functional connection between ROI correlated with the degree of anhedonia are mainly between the left ventral prefrontal cortex and left putamen(r=-0.298,p=0.039),the left ventral prefrontal cortex and right caudate nucleus(r=-0.267,p=0.039),the left putamen and right caudate nucleus(r=-0.332,p=0.021),the right putamen and right caudate nucleus(r=-0.380,p=0.008),the left caudate nucleus and right caudate nucleus(r=-0.363,p=0.011);The functional connection between ROI correlated with psychomotor speed is the functional connection between the right basal ganglia and the left thalamus(r=0.396,p=0.006).3.The differences in functional connections between m MDD and nm MDD are the whole brain functional connection of significant clusters in the left Caudate nucleus(cluster1:p=0.001)and in the right caudate nucleus(cluster2:p < 0.001),the functional connection between the left ventral prefrontal cortex and the left putamen(p=0.006),and between the bilateral Nucleus accumbens(p=0.017).The predictive model for m MDD subtype diagnosis:(1)Based on the baseline values of clinical evaluation,biological,and imaging indicators of anhedonia and psychomotor retardation,the predictive model for diagnosing m MDD subtypes constructed had poor predictive performance.The classification accuracy of validation and testing was74.00% and 64.29%,respectively,while the sensitivity and specificity of model testing were 42.86% and 85.71%.(2)Based on the changes in clinical evaluation,biological,and imaging indicators of anhedonia and psychomotor retardation during two months of follow-up,an effective predictive model for diagnosing m MDD subtypes cannot be constructed(parameters c and g indicated that the model was overfitting).The predictive model for the antidepressant efficacy of fluvoxamine:(1)Based on the baseline values of clinical evaluation,biological,and imaging indicators for anhedonia and psychomotor retardation,an effective predictive model for the antidepressant efficacy of fluvoxamine cannot be constructed(R-Squared < 0).(2)Based on the changes in clinical evaluation,biological,and imaging indicators of anhedonia and psychomotor retardation during two months of follow-up,an effective predictive model for the antidepressant efficacy of fluvoxamine cannot be constructed(R-Squared<0)..Conclusion: 1.There are some differences in psychomotor speed and imaging functional connection between melancholic MDD and non-melancholic MDD: The anhedonia and psychomotor retardation were correlated with some special imaging functional connection;2.The combination of indicators related to anhedonia and psychomotor retardation cannot construct an effective predictive model for melancholic MDD,indicating the this symptom combination cannot distinguish melancholic MDD from non-melancholic MDD;3.The combination of indicators related to anhedonia and psychomotor retardation cannot predict the two-month antidepressant efficacy of fluvoxamine in MDD.