Resting Functional Magnetic Resonance Imaging Study Of Abnormal Spontaneous Brain Activity In Patients With Stable COPD

Objective:Abnormal changes in brain structure and function in patient with chronic obstructive pulmonary disease have been reported.However,the abnormalities in local spontaneous activity in patients with stable COPD remain largely unclear.The present research apply regional homogeneity（ReHo）method,that based on voxel level,to analysis local abnormal brain activity on patients with COPD,and to explore the relationships between this kind of change and clinical parameters of patients with COPD（e.g.,pulmonary function,blood gas analysis,cognitive）.Thus,aim to describe the possible pathogenesis of congnitive impairment in patient of COPD.Materials and methods:In present study,19 patients with stable COPD were recruited,which diagnosed by the department of aspiration in the first affiliated hospital of Nanchang university,with an average age of 62.7±5.9 year.There were 20 similar（including sex,years,and number of years of education）normal control（NC）with an average age of60.8±6.3 year.Subjects in both groups underwent resting functional magnetic resonance imaging（fMRI）,arterial blood gas analysis,pulmonary function detection and neurocognitive assessment.Then,the strength of ReHo value in the whole brain of all subjects were obtained by DPABI V4.3 software based on the MATALAB2016b platform,and the two-sample t-test analysis was conducted to obtain the brain map with statistical differences in the ReHo value of the two groups.Partial correlation method was utilized to evaluate the relationship between the brain regions with altered ReHo values and the arterial blood gas analysis,lung function index and cognitive function score in COPD patients.In addition,The brain area of ReHo value difference between groups was analyzed by receiver operative characteristic（ROC）curve.Results:（1）PaO₂（p<0.001）,SaO₂（p=0.008）,FVC（p<0.001）,FEV₁（p<0.001）,and FEV₁/FVC（p<0.001）in COPD patients were significantly lower than that in the NC group,while PaCO₂ was higher than that in the NC group（p<0.001）.The total scores of COPD patients in the MoCA（p<0.001）cognitive assessment scales was lower than those in the NC group,and the scores in the MoCA scale naming（p=0.026）,visual space and execution（p=0.012）and memory tests（p<0.001）were also lower than those in the NC group.（2）Compared with NC group,the patients with COPD showed significantly lower ReHo values in the bilateral precuneus,left occipital lobe,the right lingual and right precentral gyrus,and the area showed higher ReHo value was no found.（3）Correlation analysis results showed that the ReHo value of precuneus was positively correlated with FEV₁%,FEV₁/FVC and localization function（r=0.465,p=0.045;r=0.763,p<0.001;r=0.601,p=0.070）,while negatively correlated with arterial partial pressure of carbon dioxide（r=-0.611,p=0.005）.Conclusion:The stable COPD patients demonstrated abnormal synchrony of regional spontaneous activity in various regions,and the abnormal area with abnormal ReHo values were whole related to visual processing pathway,and further correlation analysis showed partial region with ReHo abnormalities correlated with lung function,arterial blood gas analysis and cognitive evaluation,which might provide us with a new perspective to deeper understand the underlying pathophysiology of congnitive impairment in patient of COPD.