Correlation Analysis Between Alpha And Theta Oscillations In STN And Depressive Symptoms In Parkinson’s Disease

Backgroud:Parkinson’s disease(PD)is a neurodegenerative disease affecting a variety of motor and non-motor symptoms,which worsen the patients’ quality of life.At present,the treatment of the symptoms of PD patients mainly relies on medications.But when PD symptoms are very severe and medications cannot well moderate them,deep brain stimulation(DBS)can be considered as the final options for the treatment.The development of DBS provides the opportunity to directly obtain the electrical signals of the deep brain nuclei,which may provide electrophysiological basis for the diagnosis and treatment of diseases.Previous studies have found that patients with depression may have abnormal alpha and theta oscillations which is significantly related to depressive symptoms in the brain.There are also abnormal theta-alpha oscillations in STN of some PD patients.Therefore,we speculate that the abnormal alpha and theta oscillations in STN may be related to depressive symptoms in PD patients.Objective:To explore the correlation between alpha and theta oscillations of STN and the depressive symptoms in PD patients.Methods:We conducted a retrospective case-control study on 16 PD patients with(dPD group,HAMD-24≥15)or without depressive symptoms(nPD group,HAMD-24<15).We analysis that:1.the difference in the average power spectral density(PSD)of alpha and theta oscillations of the local field potential(LFP)recorded in the STN during DBS operation between dPD group and nPD group;2.the correlation between the average PSD of alpha and theta oscillations with the 24 items Hamilton depression rating scale(HAMD-24)of PD patients pre-operation and 4 months post-operation;3.factors affecting the quality of life of PD patients.Results:1.The dPD group had a higher PSD of alpha oscillations and a lower PSD of theta oscillations in the left ventral STN.2.The PSD of alpha oscillations of the left ventral STN were positively correlated to the severity of depressive symptoms in the same period,whereas the PSD of theta oscillations of the same place was negatively correlated with severity of depressive symptoms in the same period.However,the average PSD of the alpha or theta oscillations of the left ventral STN is not correlated with the severity of depressive symptoms in PD patients 4 months after DBS.3.The quality of life of PD patients is significantly related to the severity of motor symptoms,depressive symptoms,anxious symptoms,swallowing disordes,voice disorders,and sleep disorders before DBS.However,the quality of life of PD patients is only related to the severity of depressive symptoms and voice disorders4 months after DBS.Conclusion:1.The abnormal alpha and theta oscillations of the left ventral STN could be used as biomarkers of PD with depressive symptoms which might guide STN-DBS treatment.2.The motor symptoms of PD patients are greatly improved after DBS,and the existence of depressive symptoms may become one of the determinants of the quality of life of PD patients after DBS.Therefore,the improvement of depressive symptoms after DBS may contribute to better quality of life for PD patients.