Factors affecting the length of stay and hospital readmission rates after an acute exacerbation of chronic obstructive pulmonary disease: a systematic review and meta-analysis

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) are often readmitted to hospital for treatment due to an acute exacerbation of the disease. However, there are few up-to-date studies investigating the lengths of stay and risk factors for readmission after an acute exacerbation of COPD. This study evaluated the length of stay in patients with an acute exacerbation of COPD and the factors that influenced their readmission. METHODS: A search of the PubMed, Cochrane Central Register of Controlled Trials, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, and Weipu databases, carried out using the following search terms: airflow limitation, airway disease, airway obstruction, chronic obstructive pulmonary disease, COPD, length of stay and influencing factors, long-term oxygen therapy, lung disease, readmission, and respiratory system disease. The Cochrane risk of bias tool was used to evaluate the quality of the retrieved studies, and a network meta-analysis was performed using RevMan 5.20. RESULTS: Collectively, they included information on the length of stay for 630 patients who had been readmitted to hospital after an acute exacerbation of COPD (the readmitted group) and information on 688 patients who had not been readmitted (the non-readmitted group). Meta-analysis results showed that there was no difference in patient anxiety [risk ratio (RR) 1.22, 95% confidence interval (CI): 0.70–2.14] or long-term oxygen therapy (RR 1.91, 95% CI: 0.98–3.73) between the readmitted group and the non-readmitted group. However, there was a significant difference between the forced expiratory volume in one second (FEV1) predicted value [mean difference (MD) −5.85, 95% CI: −11.14 to −0.57] and the global initiative for chronic obstructive lung disease (GOLD) classification (C or D) (RR 1.61, 95% CI: 1.05–2.47). DISCUSSION: In summary, no significant relationship was found between patient state of anxiety, long-term oxygen therapy, length of hospital stay, and readmission rate after an acute exacerbation of COPD. However, FEV1 predicted values and GOLD classifications (C or D) had an impact on the length of hospital stay and readmission rate after acute exacerbation of COPD. Larger samples, multiple centers, and further research are needed to confirm the findings of this research.