A Resting-state Functional MRI Study On Newly Diagnosed Drug-naive Parkinson's Disease Patients With Anxiety

Backgroud:Anxiety could occur in all stages of Parkinson's disease(PD)even before the appearance of motor symptoms,which seriously affected the health related quality of life of PD patients.However,the pathophysiological mechanism of anxiety in PD was not fully clear.Objective:This study aimed to explore the pathophysiological mechanism of anxiety in PD by analysis regional homogeneity(ReHo)and functional connectivity(FC)of resting-state functional MRI(rs-fMRI).Methods:40 drug-naive early-stage PD patients were divided into PD with anxiety(n=21)and PD without anxiety(n=19)based on the Hamilton anxiety rating scale(HAMA)scores in our cross-sectional studies.20 healthy volunteers with similar age,sex and education level were included as normal controls(NC).All participants were scanned with 3.0 T MRI apparatus.SPM 12.0 software package on MATLAB 2013b platform was used for ReHo and FC analsis.Results:13 male early-stage PD patients and 27 female early-stage PD patients were include in this study,the average age was 60.43±7.47 years,the average age of onset 57.92± 8.43 years,the average education time was 4.98± 7.43 years,the average duration was 1.24 ± 0.36 years,the average Hoehn and Yahr stage(H&Y stage)was 1.17±0.64,the average Unified Parkinson's Disease Rating Scale part ?(UPDRS ?)total score was 20.25±10.47,the average Montreal Cognitive Assessment(MoCA)score was 19.24± 3.57,the average Non-Motor-Symptoms Scale(NMSS)score was 21.57 ±10.29,the average HAMA score was 12.91± 2.86,and the average Hamilton Depression Rating Scale(HAMD)score was 3.42±1.35.The HAMA score of PD patients with anxiety were significantly higher than PD patients without anxiety.The duration,age of onset,H&Y stage and scores of UPDRS III,MMSE,MoCA,NMSS and HAMD of PD patients with anxiety were no significantly different from PD patients without anxiety.The ReHo values of the left cerebellum and the left middle frontal gyrus were obvious different among PD patients with anxiety,PD patients without anxiety and NC,The ReHo values of PD patients with anxiety increased significantly in left cerebellum and decreased significantly in the left middle frontal gyrus than PD patients without anxiety and NC respectively in post-hoc t test paired comparisons.The ReHo values of PD patients without anxiety decreased significantly in the left middle frontal gyrus than NC.The left cerebellum with significantly increased ReHo value and the highest Peak value was choosed as region of interest(ROI)for further FC analysis.The FC values between left cerebellum and right cerebellum,left inferior temporal gyrus,right middle temporal gyrus,right caudate nucleus,and right anterior cingulate cortex were obvious different.The FC values between left cerebellum and right cerebellum of PD patients with anxiety decreased significantly while FC values between left cerebellum and right caudate nucleus,the right anterior cingulate cortex increased significantly than PD patients without anxiety in post-hoc t test paired comparisons.The FC values between left cerebellum and right cerebellum of PD patients with anxiety decreased significantly than NC.All results aboved were corrected by GRF(cluster-level P value<0.001,voxel-level P value<0.05).The HAMA scores of PD patients with anxiety were significantly negative correlated with ReHo values of left middle frontal gyrus and FC values between left cerebellum and right cerebellum in Pearson correlation analysis.Conclusion:Anxiety was common in PD and associated with local abnormal spontaneous electrical activity of left cerebellum and left middle frontal gyrus,Changes of FC between left cerebellum and right cerebellum,and changes of FC between left cerebellum and right caudate nucleus,left cerebellum,right anterior cingulate cortex may be involved in brain functional network mechanism of anxiety in PD.