| Objective To evaluate the risk factors for readmission within 1 year in patients with acute exacerbation of chronic obstructive pulmonary disease（AECOPD）combined with cardiac dysfunction and to develop a predictive model.Methods Patients with AECOPD combined with cardiac dysfunction who were hospitalized at the First Hospital of Lanzhou University from January 2018 to December 2019 were retrospectively included.The basic characteristics of the patients,the first routine blood results after admission,the main indicators of pulmonary function,the indicators of cardiac function,the last routine blood results before discharge,the interval of hospitalization,the comorbidities and the readmission of the patients within 1 year were recorded through the electronic medical record system.1.Patients were divided into a readmission within 1 year group and a no readmission within 1 year group according to whether they were readmitted within 1year after being discharged from hospital after treatment.The basic characteristics of the patient,the first routine blood results after admission,the main indicators of pulmonary function,the indicators of cardiac function,the last routine blood results before discharge,the patient’s length of stay,comorbidities and readmission within 1year are recorded through the electronic medical record system.2.Data from this study were analysed using SPSS 26.0 and R 4.2.2 software.Dichotomous or multicategorical variables were expressed as frequencies（percentages）,and between-group comparisons were only made using the chi-square test to compare the differences between the two groups of patients.Continuous variables were first tested for normal distribution,and if the continuous variables conformed to a normal distribution,they were expressed as mean±standard deviation（Mean±SD）and the means between the two groups were compared using the independent samples t-test;if the continuous variables did not conform to a normal distribution,they were expressed using the median（interquartile spacing）and the two groups were compared using a non-parametric test.Haematological parameters with a heavily skewed distribution were log-transformed and converted to dichotomous variables for analysis using a calculation of the subject operating characteristic（ROC）curve with the area under the curve（AUC）taking the best cut-off value.Binary logistic regression was used to analyse whether the inclusion factor was a risk factor for readmission within 1 year in patients with AECOPD combined with cardiac dysfunction.We considered P<0.05 to be statistically different.R 4.2.2 was applied to construct a predictive model for the column line graph,and the model was internally validated using the Bootstrap method,and calibration curves were plotted to produce a consistency index,subject operating characteristic（ROC）curves were plotted,and the area under the curve was calculated to assess the predictive validity of the model,and the clinical applicability of the model was assessed by clinical decision curve analysis.3.Risk factors associated with readmission within 1 year in patients with AECOPD combined with cardiac dysfunction were included,a column line graph prediction model was developed using R language,and internal validation and clinical effectiveness analysis were completed.Results 1.A total of 298 patients with AECOPD combined with cardiac dysfunction were included in this study,of whom 197（66.1%）were male patients and101（33.9%）were female patients.Among them,there were 126 patients in the readmission group within 1 year,including 86（68.3%）male patients and 40（31.7%）female patients;172 patients in the no readmission group within 1 year,including 111（64.5%）male patients and 61（35.5%）female patients.The results of the univariate analysis suggested that:percentage of neutrophils tested on admission,percentage of eosinophils tested on discharge,B-type natriuretic peptide,Pa O2,Sa O2,FEV1,smoking index,Aspergillus infection and FEV1pre≤50%were risk factors for readmission within 1 year in patients with AECOPD combined with cardiac insufficiency.2.Three risk factors associated with readmission within 1 year of discharge were finally screened by covariate diagnosis with binary logistic regression analysis,arterial oxygen saturation（OR=0.972,95%CI:0.946-0.998;P=0.038）,B-type natriuretic peptide（OR=0.423,95%CI:0.195-0.921;P=0.030）,Aspergillus infection（OR=0.099,95%CI:0.011-0.924;P=0.042）.A line graph model was constructed based on the above three independent risk factors,and the model was validated using the Bootstrap method with a consistency index of 0.677（95%CI:0.575-0.780）,and the calibration curve fitted well with the ideal curve.Conclusion A line graph risk prediction model based on three predictors,namely arterial oxygen saturation,B-type natriuretic peptide and Aspergillus infection,for readmission within 1 year in patients with AECOPD combined with cardiac insufficiency has good predictive ability and clinical applicability,which can provide reference for clinicians to screen high-risk patients and help reduce the incidence of readmission within 1 year. |
