infection increases the readmission rate of COPD patients.

Introduction: Acute exacerbation of COPD (AECOPD) leads to rapid deterioration of pulmonary function and quality of life. It is unclear whether the prognosis for AECOPD differs depending on the bacterium or virus identified. The purpose of this study is to determine whether readmission of patients with severe AECOPD varies according to the bacterium or virus identified.

Methods: We performed a retrospective review of medical records of 704 severe AECOPD events at Korea University Guro Hospital from January 2011 to May 2017. We divided events into two groups, one in which patients were readmitted within 30 days after discharge and the other in which there was no readmission.

Results: Of the 704 events, 65 were followed by readmission within 30 days. Before propensity score matching, the readmission group showed a higher rate of bacterial identification with no viral identification and a higher rate of identification with the (=0.003 and =0.007, respectively). Using propensity score matching, the readmission group still showed a higher identification rate (=0.030), but there was no significant difference in the rate of bacterial identification, with no viral identification (=0.210). In multivariate analysis, the readmission group showed a higher identification rate than the no-readmission group (odds ratio, 4.749; 95% confidence interval, 1.296-17.041; =0.019).

Conclusion: identification is associated with a higher readmission rate in AECOPD patients.