The Study Of Cerebral Autoregulation In Patients With Depression

Research purposes:The purpose of this study was to investigate the function of cerebral autoregulation（CA）in depressed patients.To explore the relationship between various clinical manifestations of depression and CA to gain a deeper understanding of the pathophysiological mechanism of depression.These would help to discover of new auxiliary examination methods to guide clinical evaluation and treatment.Research methods:A total of 65 depressed patients and 43 healthy people were included in this study.General clinical data such as gender,age,BMI,education level,study and work situation,labor type,marital status,and place of residence were collected.The HAMD-17,SAS and PHQ-15 scales were used to assess the subjects’ degree of depression,anxiety and somatic symptoms.The dynamic cerebral autoregulation（d CA）was monitored by combined Transcranial Doppler Ultrasound（TCD）and non-invasive finger blood pressure,and recorded continuously for 10 minutes.The data of cerebral blood flow velocity（CBFv）and blood pressure was analyzed by transfer function analysis,and the d CA parameters such as phase difference（PD）,gain,rate of recovery CBFv（Ro Rc）were derived.Subsequently,supine-to-stand cerebral blood flow regulation was performed.First,the subjects lied supine on the examination bed for 2～3 minutes.Secondly,the subjects were instructed to change from the supine position to the upright position,monitored CBFv for 2 minutes and finally returned to the supine position for 2～3 minutes.The left middle cerebral artery CBFv was recorded continuously in three stages.Peak systolic flow velocity（Vs）and end-diastolic flow velocity（Vd）in supine and upright positions were measured twice each,and the average value was taken.Calculating the difference between Vs and Vd supine-to-stand positions respectively.Statistical analysis of the obtained data was performed to evaluate CA function in depressed patients.Results:There was no statistical difference in general clinical data between the depression group and the control group.Depressed patients had significantly higher HAMD-17,SAS and PHQ-15 scores than healthy individuals.Compared with the control group,PD in left and right sides were decreased in the depression group,but there was no difference in PD between the two sides.The bilateral gain had an increasing trend,and the bilateral Ro Rc had a decreasing trend in the depression group,but there was no statistical difference.In addition,the difference of Vs and Vd between supine-to-stand positions in the depression group was significantly greater than that in the control group.There was no significant difference in bilateral PD between the mild depression group and the control group.Compared with the control group and the mild depression group,the bilateral PD was lower in the moderate depression group,and the left PD was significantly lower in the severe depression group.There were no significant differences in PD,gain,and Ro Rc between depression alone,depression with mild anxiety,and depression with moderate to severe anxiety.The same results were found in mild,moderate,and severe somatic symptom groups.We also found that anxiety and somatic symptoms affected the difference in Vd between supine-to-stand positions.The more severe the somatic symptoms,the smaller the Vd difference between supine-tostand positions.After correlation analysis,univariate and multivariate analysis,it was found that PHQ-15 scores was positively correlated with HAMD-17 scores,and age and HAMD-17 scores were the independent influencing factors of left PD in depressed patients.Conclusion:1.CA was impaired in depressed patients.2.Subgroup analyses showed that d CA was not impaired in patients with mild depression.But d CA was significantly impaired in patients with moderate and severe depression.Anxiety had no effect on d CA in patients with depression.Anxiety and somatic symptoms could affect the difference in Vd between supine-to-stand positions.3.Age and HAMD scores were the independent influencing factors of left PD in depressed patients.4.In patients with depression,the more severe the somatic symptoms,the more severe the depressive symptoms.