The Relationship Between Oxidative Stress Factors And Complicated Cognitive Impairment In Chronic Obstructive Pulmonary Disease And Their Clinical Significance

ObjectivesTo explore the relationship and clinical significance of serum oxidative stress factors 8-OHdG,3-NT,8-iso-PGF_2α,T-SOD on chronic obstructive pulmonary disease（COPD）with and without cognitive impairment,and to provide new prevention and treatment ideas for clinical COPD complicated with cognitive impairment.MethodsThe cognitive domain of COPD patients hospitalized in respiratory department of our hospital from January 2016 to December 2017 was assessed by the Montreal Cognitive Assessment（MoCA）scale.According to the results,53 COPD patients with cognitive impairment were selected as the case group and 53 COPD patients as the control group.The general clinical data,blood gas analysis and lung function of the two groups were analyzed respectively.Enzyme-linked immunosorbent assay（Enzyme-linked immunosorbent assay）was also used.The serum levels of 8-OHdG,3-NT,8-iso-PGF_2αand T-SOD were measured by ELISA.The clinical value of these factors in screening COPD with or without cognitive impairment was evaluated by receiver operating characteristic curve（ROC）.The data were analyzed by SPSS20.0software.Results 1 There was no significant difference in sex,age,body mass index and years of education between COPD with cognitive impairment and simple COPD group（P>0.05）,but there was significant difference in smoking index（P<0.05）.2 There was no significant difference in hypertension,diabetes mellitus,coronary heart disease,cerebral infarction and chronic nephropathy between COPD with cognitive impairment and simple COPD group（P>0.05）.3 There was no significant difference in blood gas analysis between the two groups in PH value and PaO₂（P>0.05）,but there was significant difference in PaCO₂ level.PaCO₂ level in COPD with cognitive impairment group was significantly higher than that in simple COPD group（P<0.05）.4 There was no significant difference in lung function between the two groups in FEV1/FVC and FEV1%pred（P>0.05）.5 The levels of 8-iso-PGF_2a,8-OHdG and 3-NT in COPD with cognitive impairment group were significantly higher than those in COPD without cognitive impairment group,and the activity of T-SOD was significantly lower than that in simple COPD group（P<0.05）.6 Smoking index and PaCO₂ levels were correlated with COPD with cognitive impairment.The higher the smoking index,the higher the risk of COPD with cognitive impairment.After excluding smoking index and PaCO₂ level,the levels of8-iso-PGF_2a,8-OHdG,3-NT and T-SOD activity were significantly correlated with cognitive impairment in COPD patients.The higher the levels of 8-iso-PGF_2a,8-OHdG and 3-NT,the higher the risk of cognitive impairment in COPD patients.The lower the level of T-SOD activity,the higher the risk of cognitive impairment in COPD patients.7Multivariate logistic regression analysis showed that smoking index was not related to COPD with cognitive impairment,but PaCO₂,T-SOD,3-NT,8-OHdG,8-iso-PGF_2aa were all related to COPD with cognitive impairment,among which 8-OHdG was most closely related to COPD with cognitive impairment.8 The area under the ROC curve of COPD patients’cognitive impairment predicted by 8-OHdG level was 0.780（95%CI 0.687,0.873）,and the sensitivity and specificity were 58.5%and 92.5%respectively.8 The area under ROC curve of 8-OHdG combined with T-SOD for predicting cognitive impairment in COPD patients was 0.868（95%CI 0.801,0.935）.The sensitivity and specificity were92.5%and 67.9%respectively.Conclusions1 8-OHdG,3-NT,8-iso-PGF_2a,T-SOD were associated with cognitive impairment in COPD patients.With the increase of 8-iso-PGF_2a,8-OHdG and 3-NT levels,the risk of cognitive impairment in COPD patients increased.With the decrease of T-SOD level,the risk of cognitive impairment in COPD patients increased.2 8-OHdG can predict cognitive impairment in COPD patients to some extent,but its sensitivity is low.The combination of 8-OHdG and T-SOD can significantly improve the sensitivity in predicting cognitive impairment in COPD patients.Figure2;Table18;Reference135...