The Early Warning Factors Of Venous Thromboembolism Among Patients With Acute Exacerbation Of Chronic Obstructive Pulmonary Disease

Objective:Chronic Obstructive Pulmonary Disease(COPD)is a common disease of the respiratory system,mainly occurring in middle-aged and elderly people,whose main clinical symptoms are repeated cough,expectoration,dyspnea and so on.AECOPD is the acute exacerbation of chronic obstructive pulmonary disease,which refers to the sudden exacerbation of clinical symptoms of COPD patients in a short period of time.When the condition is serious or complications occur,it can directly affect the clinical prognosis of patients and even threaten life.Venous thromboembolism(VTE)is a common complication in patients with AECOPD.There are two main types: deep venous thrombosis(DVT)and pulmonary thromboembolism(PTE).Because some patients with VTE have very similar clinical symptoms with AECOPD,physicians often pay attention to AECOPD in clinical diagnosis and neglect VTE complications,resulting in delays in diagnosis and treatment.This study intends to find possible early warning factors by analyzing the clinical data of VTE in AECOPD patients,and provide basis for early diagnosis and active prevention and treatment.Methods:From January 2015 to December 2019,441 AECOPD inpatients from the Pulmonary Circulation Department of Shanghai Pulmonary Hospital and the Respiratory Medicine Department of our hospital were retrospectively analyzed.The results of ultrasound and CT pulmonary angiography of the lower limb vein were used to determine whether the patients were complicated with VTE,and the incidence of VTE in AECOPD patients was calculated.AECOPD patients with VTE were included in VTE group,and AECOPD patients without VTE were included in non VTE group.The data of gender,age and other general data,lower limb pain and swelling,walking difficulty,fever and other clinical symptoms,bed time,hormone use,diuretic use and other treatment data,laboratory blood routine,biochemical,blood gas analysis,lung function,cardiac ultrasound and other indicators were collected.Data statistics of the two groups of patients: if the continuous data were normal distribution and variance homogeneity,two independent samples t test was used,otherwise Wilcoxon rank sum test was used;chi square test or exact probability method was used for classified data according to the actual situation,and Wilcoxon rank sum test was used for grade data.Multivariate logistic regression was used to screen the early warning factors.Logistic stepwise regression method was used to establish the model,and nomogram was used to show the prediction model.Results:(1)Among 441 patients with AECOPD,57 patients had VTE,with an incidence of 12.92%.Among them,there were 12 patients with PTE,with an incidence of 2.72%,42 patients with DVT,with an incidence of 9.52%,and 3 patients with DVT and PTE,with an incidence of 0.68%;(2)The results of univariate analysis showed that the incidence of VTE group was not significantly different from that of patients in terms of gender,history of thrombophlebitis,varicose veins of lower limbs,use of hormones and diuretics(P > 0.05).In VTE group,there were 16 cases(28.07%)with venous thrombosis,22 cases(38.6%)with lower limb swelling,21 cases(36.84%)with walking difficulty,8 cases(14.04)with lower limb pain,16 cases(28.07%)with increased heart rate,23 cases(40.35%)with fever duration ≥ 3 days and bed time ≥ 3 days,38 cases(66.67%)with high Padua score,and the difference was statistically significant(P < 0.05).The incidence of VTE group was not significantly different from that of white blood cell(WBC),hemoglobin(Hb),platelet(PLT),plasma fibrinogen(Fib),D-dimer(D-D),brain natriuretic peptide(BNP),C-reactive protein(CRP),cardiac troponin(Tn I),procalcitonin(PCT)and forced vital capacity(FVC)in the percentage of predicted values(P > 0.05).The VTE group had statistically significant differences in hydrogen ion concentration index(PH),arterial partial pressure of oxygen(Pa O2),arterial partial pressure of carbon dioxide(Pa CO2),erythrocyte sedimentation rate(ESR),activated partial thromboplastin time(APTT),homocysteine(Hcy),pulmonary artery systolic pressure(PASP),percentage of forced expiratory volume in the first second(FEV1%),DLco,etc.(P < 0.05);(3)Multivariate logistic regression analysis found that the early-warning factors of AECOPD patients with VTE were as follows:bed-rest time(> 3 days),history of venous thrombosis,lower limb swelling,fever(> 3 days),increased D-D,decreased Pa CO2 and Sp O2,increased ESR,and decreased FEV1%.(4)The prediction model is presented by nomogram,the overall accuracy of the model was 96.15%,95% CI was(93.90%,97.74%),sensitivity was 77.19%,specificity was 98.96%,positive predictive value was 91.67%,negative predictive value was 96.69%.According to the above variables,the occurrence of VTE can be well predicted,the area under ROC curve was 0.881.Conclusion:There are many predictive factors of venous thromboembolism in patients with AECOPD,and the incidence of VTE is as high as 12.92%.Among them,age,bedridden time ≥ 3 days,history of venous thrombosis,swelling of lower limbs,fever ≥ 3 days,increase of D-D and ESR,decrease of Pa CO2 and Sp O2,and decrease of FEV1% are important early warning factors.The performance of VTE prediction model based on early warning factors needs to be further verified by larger clinical samples.It is necessary to evaluate AECOPD patients with early warning factors in clinical work.Patients with VTE risk should arrange relevant examination as soon as possible to make a clear diagnosis.Once diagnosed,active treatment should be taken to prevent the disease from aggravating and reduce the mortality rate.