A Retrospective Real-world Cohort Study Of Bronchoalveolar Lavage In The Treatment Of Pneumoconiosis

Objective（s）:Through a real-world retrospective cohort study,the short-term efficacy and safety of bronchoalveolar lavage in the treatment of pneumoconiosis were observed,the effects of bronchoalveolar lavage on Long-term lung function in patients with pneumoconiosis were discussed,and the effects of bronchoalveolar lavage on survival status of patients with pneumoconiosis were analyzed.Methods:1.Build a database for the study.Through the analysis of clinical data of patients with pneumoconiosis diagnosed and treated in two Grade A comprehensive hospitals in Yunnan Province from January2013 to January 2018,a total of 1,175 patients were included in 1654 cases,and the database was established.Bronchoalveolar lavage was used as the exposure factor,and the patients were divided into conventional group and lavage group.The conventional group was given conventional therapy,and the lavage group was given bronchoalveolar lavage on the basis of conventional therapy.2.To observe short-term efficacy and safety bronchoalveolar lavage in the treatment of pneumoconiosis.The symptom changes of pneumoconiosis patients before and after treatment were compared between the two groups.The intraoperative and postoperative complications of lavage group were observed.Qualitative data were expressed as relative numbers,We balanced confounding factors by matching propensity scores,and the Chi-square test was used for comparison between groups.3.To investigate the effect of bronchoalveolar lavage on Long-term lung function in pneumoconiosis patients.Patients with pneumoconiosis who were followed up for more than 2 years and qualified for pulmonary function report were selected from the database,and The annual decline of pulmonary function indexes in the first second forced expiratory volume in the two groups was observed.Student’s t-test was used for inter-group differences,and paired t test was used to compare intra-group differences.4.To analyze the effects of bronchoalveolar lavage on the survival status of the Patients with pneumoconiosis.The patients admitted for the first time were selected,and the survival status of the two groups at 3 and 5 years after treatment was observed after PSM balanced confounding factors.The Kaplan–Meier method was used to estimate the rate of survive,and the log-rank test was used to compare the distribution of survival curves between two groups.Results:1.A total of 736 cases were included in the lavage group and 918 cases in the conventional group,and 524 cases were included in the lavage group and the conventional group,respectively,after balancing the confounding factors of age,years of exposure to dust and Smoking status.The improvement rates of cough,sputum,chest tightness,wheezing,chest pain and dyspnea after treatment were in the lavage group were higher than those in the conventional group（98.0%,97.3%,93.2%,94.7%,91.2%,87.5%vs 94.3%,93.7%,76.1%,89.3%,79.4%,69.6%）and the differences were statistically significant（P<0.05）.The incidence of intraoperative and postoperative complications of 736 patients in lavage group was 1.22%,including transient fever in7 cases,nasal bleeding in 1 case and induced arrhythmia in 1 case.2.178 patients with pneumoconiosis who were followed up for more than 2 years and qualified for pulmonary function report were included,including 84 patients in the conventional group and 94 patients in the lavage group.In contrast,the annual decline in the FEV₁ after bronchoalveolar lavage was significantly less in the lavage group than in the conventional group（45.17±17.33ml per year vs 61.34±22.25ml per year;difference,16 ml per year[95%CI,10.30 to 22.04],P<0.001）.3.A total of 612 patients were selected based of PSM.Before matching,there were statistically significant differences in age,years of exposure to dust,Smoking status and underlying diseases between groups（P<0.001）,but after matching,there were no statistically significant differences between groups（P>0.05）.Kaplan-Meier survival curve showed that the 3-year overall survival rate was 94.1%,and that of the lavage group was 95.8%,which was slightly higher than that of the conventional group（92.5%）,but the difference was not statistically significant（P>0.05）.The5-year overall survival rate was 87.3%,and the survival rate of the lavage group was90.2%,which was higher than that of the conventional group（84.3%）,with statistical significance（P<0.001）.Conclusion（s）:1.Bronchoalveolar lavage can effectively relieve the clinical symptoms of patients with pneumoconiosis,with low complication rate,effective and safe.2.Bronchoalveolar lavage ameliorated the annual decline in the FEV₁ after treatment in patients with pneumoconiosis.3.Bronchoalveolar lavage improves the 5-year survival rate of pneumoconiosis patients.