A Study Of Cognitive Dysfunction And Brain Functional Changes In Patients With Stable Chronic Obstructive Pulmonary Disease

Objective:The study was aimed to explore the influence of C-reactive protein?CRP?,procalcitonin?PCT?,neutrophil/lymphocyte ratio?NLR?and blood gas analysis results in patients with chronic obstructive pulmonary disease and meanwhile,to evaluate the intrinsic brain activity in COPD patients using the amplitude of low-frequency fluctuation?ALFF?method.Methods:The Montreal cognitive function scale?MoCA?score was performed on 120patients with COPD admitted to the respiratory department of the first affiliated hospital of Nanchang university from December 2017 to March 2019.According to MoCA score,63 patients in the cognitive impairment group and 57 patients in the cognitive normal group were divided into two groups,meanwhile,indicators such as CRP,PCT,NLR,PaO₂,PaCO₂ and SaO₂ were detected in the two groups,and the clinical diagnostic value of these indicators in patients with cognitive dysfunction in COPD was evaluated through receiver operating characteristic curve?ROC?.Among them,19 patients with COPD agreed to accept resting-state functional MRI scans respiratory functions tests,at the same time,20 recruited normal controls?NCs?matched in age,sex,and education subjected to the same tests.The local spontaneous brain activity was examined using the voxel-wise ALFF.Pearson's correlation analysis was used to investigate the relationships between the brain regions with altered ALFF signal values and the clinical features in COPD patients.Results:1.Compared with the normal cognitive group,CRP,PCT,NLR and PaCO₂ were significantly increased and PaO₂ was significantly decreased in the cognitive impairment group,with statistically significant differences?p<0.001?,while SaO₂,age,and gender were not significantly different between the two groups.The area under the ROC curve for the prediction of cognitive dysfunction in COPD patients by individual and combined detection was as follows:CRP 0.910?95%ci:0.776-0.977?,PCT 0.945?95%CI:0.823-0.992?,NLR 0.897?95%CI:0.765-0.971?,PaO₂ 0.966?0.855-0.998?,PaCO₂ 0.959?0.843-0.996?,and combined detection 0.982?95%CI:0.881 to 1.000?.2.Compared with the NCs,COPD patients showed significantly lower cognitive function scores.Also,lower ALFF areas in the cluster of the posterior cingulate cortex?PCC?and precuneus,as well as a higher ALFF area in the brainstem were also found in COPD patients.The mean ALFF values in the PCC,precuneus,and brainstem showed high sensitivity and specificity in operating characteristic curves analysis,which might have the ability to distinguish COPD from NCs.Meanwhile,the mean signal values of the lower ALFF cluster displayed significant positive correlations with FEV1/FVC proportion and significant negative correlation with PaCO2;the higher ALFF cluster showed significant positive correlation with FEV1 proportion in COPD.Conclusion:Inflammatory indicators and blood gas analysis have important guiding significance for the diagnosis of cognitive impairment in COPD patients.Furtherm ore,according to the results of the present study,the COPD patients showed abnormal intrinsic brain activities in the precuneus,PCC,and brainstem,which might provide useful information to better understand the underlying pathophysiology of cognitive impairment.