The Clinical Value Of Red Blood Cell Distribution Width And Superoxide Dismutase In Patients With Chronic Obstructive Pulmonary Disease

1.Background and ObjectiveChronic Obstructive Pulmonary Disease(COPD for short)has increased morbidity and mortality worldwide year after year,causing serious economic and social burdens.At present,it is considered that inflammation and oxidative stress are two important mechanisms for the development of COPD.Inflammation and oxidative stress can increase Red Cell Distribution Width(RDW for short),and some studies suggest that RDW is associated with the severity and prognosis of COPD,but its significance in predicting AECOPD has not been widely recognized clinically.Superoxide Dismutase(SOD for short)can inhibit oxidative stress and inflammation.If oxidative stress is related to changes in blood RWD and SOD values,there should be a correlation between RDW and SOD;if these two indicators can independently predict the progression of COPD,then the combining these indicators to predict the progress of COPD and to eveluate treatment effect shall be more advantageous?At present,there are few studies on these issues.Since both RWD and SOD data are easily collected and monitored,it is necessary to conduct an in-depth study of their status in the evaluation of COPD.This study was to investigate the effect of RDW and SOD on the severity and therapeutic effect of COPD.At the same time,the correlation between RDW and SOD and other inflammatory markers and lung function was analyzed to further understand the change of RDW and SOD in COPD,providing new ideas for the assessment and treatment of COPD.2.Research objects and methods2.1 Research objectThis study is a retrospective analysis.A total of 80 inpatients in the People’s Liberation Army 305 Hospital during the period from 2012 to 2017 that met the criteria for the AECOPD,74 outpatients who met the criteria for stable COPD and 87 normal person serving as the control group were selected from the physical examination center of our hospital to collect a variety of data.The three study groups were matched for gender and age.2.2 Data CollectionCollect patient’s age,sex,total length of hospitalization,total hospitalization data,(average)number of acute exacerbations within a year,complication of pulmonary heart disease,mMRC scores,etc.;detailed records of white blood cell count,neutrophil percentage,lymphocyte percentage,RDW,SOD,serum C-reactive protein,serum albumin,brain sodium and other experimental group indicators;collection of lung function data:FEV1,FEV1%pred,FVC,FEV1/FVC%2.3 Statistical MethodsApply SPSS20.0 software to do statistical analysis.Measured data were expressed as mean±standard deviation.The mean of the two groups was compared using independent sample t-test.One-way ANOVA was used to compare between more than two groups..The count data is represented by the composition ratio,and the comparison between groups is performed using the chi-square test.The correlation analysis uses the Pearson test.The ROC curve was used to analyze the diagnostic value,sensitivity,specificity,and node values of related indicators.Selecting P<0.05 was considered statistically significant.3.Results(1)The RDW,WBC,CRP,and NLR in the AECOPD group were higher than those in the stable COPD group and healthy control group.The SOD was lower than that in the stable COPD group and the healthy control group.The differences between the two groups were statistically significant.(all P<0.05).(2)Both in the AECOPD group and the stable COPD group,RDW was negatively correlated with SOD,and the blood RDW was positively correlated with BNP in AECOPD patients(both P<0.05).(3)COPD patient was grouped by lung function GOLD Grade,serum RDW levels are grade IV>grade III>grade II>grade I;serum SOD levels are grade I>grade II>grade III>grade IV;Both FEV1/FVC and FEV1%pred were negatively correlated with blood RDW and positively correlated with SOD in both AECOPD group and stable COPD group.AECOPD patients were divided into four groups according to the average of RDW and SOD.FEV1/FVC and FEV1%pred were the lowest in RDW high SOD low group,and FEV1/FVC and FEV1%pred were highest in RDW low SOD high group(all P<0.05).The sensitivity of SOD in diagnosing COPD patients with lung function damage was 91.37%,specificity was 88.7%,AUC was 0.876;RDW sensitivity was 42.6%,specificity was 94.8%,AUC was 0.649;The sensitivity of combinating SOD and RDW to diagnose COPD patients with lung function damage was 91.37%,the specificity was 88.7%,and the AUC was 0.959.(4)The blood RDW levels in patients with AECOPD complicated with pulmonary heart disease were significantly higher than those in non-complicated patients;the RDW levels in patients with frequent acute exacerbations were significantly higher than those in normal acute exacerbations patients,and the SOD levels were significantly lower than those in common attack patients;COPD patients were grouped by ABCD tools.RDW levels was Group D>C>B>A,SOD was A>B>C>D;AECOPD patients were divided into two groups by RDW,SOD mean.In the RDW high group mMRC score was higher than that in the RDW low group(all P<0.05).In the high SOD group mMRC score was lower than that in the low SOD group,but there was no significant difference between the two groups(P>0.05).(5)Serum RDW levels in the AECOPD group were positively correlated with days of hospitalization and hospitalization costs,and SOD levels were negatively correlated with hospital days(P<0.05).(6)AECOPD patients were divided into four groups according to the average of RDW and SOD.The proportion of D group,frequent acute exacerbation,and MMRC score were the highest in high RDW low SOD group,and the proportion of D group,frequent acute exacerbation,and MMRC score were the lowest in low RDW high SOD group(7)The sensitivity of SOD in diagnosing chronic obstructive pulmonary disease during acute exacerbation was 92.4%,specificity was 52.5%,AUC was 0.707,RDW sensitivity was 55%,specificity was 71.4%,AUC was 0.678,CRP and WBC sensitivity were 70.3%80%respectively,the specificity was 72.1%,53.2%respectively,and the AUC was 0.730,0.7 respectively.The diagnostic sensitivity of SOD combined with RDW was 86.7%,the specificity was 82.5%,and the AUC was 0.912.4.Conclusion1.RDW,SOD can reflect the degree of inflammation in patients with COPD.2.Both of blood RDW,SOD have the value to assess COPD severity.The assessment of RDW combining with SOD is better than a single assessment.3.RDW and SOD have the value of assessing lung function impairment in COPD patients alone.And SOD combining with RDW is more effective than single diagnosis in evaluating lung function impaiment of COPD patients.4.RDW has a certain reference value for diagnosing COPD associated with pulmonary heart disease.