Network Centrality Measured By Resting-state FMRI In Non-neuropsychiaric Systemic Lupus Erythematosus

Objective:Using voxel-wise degree centrality(DC),as measured by resting-state functional magnetic resonance imaging(rs-fMRI),we aimed to investigate the functional brain network in systemic lupus erythematosus(SLE)patients without neuropsychological symptoms(non-NPSLE),which can help finding clues for diagnosis of neuropsychiaric systemic lupus erythematosus(NPSLE)earlier and understanding its pathogenesis further.Methods:Firstly,24 non-NPSLE patients(non-NPSLE group)and 24 gender-and age-matched healthy controls(HCs group)were enrolled to undergo rs-fMRI and 3D-T1 MRI scans,then clinical data of non-NPSLE patients were collected as well as systemic lupus erythematosus disease activity index(SLEDAI)scores were calculated.Then,image data were processed by an fMRI processing assistant called DPARSF on the Matlab 2012 a station and the rs-fMRI data were analyzed by using voxel-based DC method(the matrix correlation coefficient threshold was 0.25).Finally,statistical analysis was done to compare the group differences of DC and population and the correlation between brain regions with DC value statistically different and clinical variables was analyzed in non-NPSLE group.Results :1.Compared with HCs group,non-NPSLE group showed decreased DC in several areas including right medial frontal gyrus/superior frontal gyrus/middle frontal gyrus,right caudate nucleus,left middle frontal gyrus/inferior frontal gyrus,left anterior cingulate cortex,posterior lobe of left cerebellum,but increased DC in right postcentral gyrus/precuneus/paracentral lobule.2.Correlation analysis showed a positive correlation between DC value of right medial frontal gyrus/superior frontal gyrus/middle frontal gyrus and C3 in non-NPSLE group.Conclusions:1.Our research showed that alteration of functional brain network was already present in non-NPSLE patients whose conventional brain MRI was negative,suggesting that they may had been in the stage of subclinical NPSLE.So it was necessary for early assessment and intervention in non-NPSLE patients to prevent a further damage of cerebral function which may result in NPSLE eventually.2.Our research also showed that there was a positive correlation between DC value of right medial frontal gyrus/superior frontal gyrus/middle frontal gyrus and C3 in non-NPSLE group,indicating that cerebral dysfunction in some areas of non-NPSLE patients may be related to C3.This would lead to an further understanding of the underlying pathogenesis of NPSLE and provide a potential direction for the development of early intervention.