Qinglin Chen,1,* Xinmao Wang,1,* Xiujuan Yao,1 Luo Zhang,2– 4 Xiaofang Liu1 

1Department of Respiratory and Critical Care Medicine, Beijing Tongren Hospital, Capital Medical University, Beijing, People’s Republic of China; 2Beijing Laboratory of Allergic Diseases, Beijing Municipal Education Commission, Beijing, People’s Republic of China; 3Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, People’s Republic of China; 4Key Laboratory of Otolaryngology Head and Neck Surgery of Ministry of Education of China, Beijing Institute of Otolaryngology, Beijing, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Xiaofang Liu, Department of Respiratory and Critical Care Medicine, Beijing Tongren Hospital, Capital Medical University, No.2, Xinanhuan Road, Yizhuang District, Beijing, 100176, China, Email xfliutrhos@163.com Luo Zhang, Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University; Key Laboratory of Otolaryngology Head and Neck Surgery of Ministry of Education of China, Beijing Institute of Otolaryngology, No. 17, Hougou Hutong, Chongnei, Dongcheng District, Beijing, 100730, China, Email dr.luozhang@139.com

Purpose: The aim of this study was to explore the predictive value of the chronic obstructive pulmonary disease (COPD) specific comorbidity test index (COTE) and pulmonary comorbidities for moderate-to-severe acute exacerbation and hospitalization in COPD patients.
Patients and Methods: This was a retrospective cohort study. We included 470 patients with stable COPD. Patients were divided into high or low-risk comorbidity group according to whether COTE score ≥ 4, and pulmonary comorbidities and extrapulmonary comorbidities group according to comorbidity origin. Moderate-to-severe acute exacerbation events and other clinical parameters were compared between groups. Multifactorial analysis and Lasso regression were used to screen risk factors and establish predictive models for moderate-to-severe acute exacerbation and hospitalization. The receiver operating characteristic (ROC) curve was used to assess the value COTE score and pulmonary comorbidities in predicting moderate-to-severe acute exacerbation and hospitalization.
Results: When compared with the low-risk comorbidity and extrapulmonary comorbidities group, the rate of patients with ≥ 2 moderate-to-severe acute exacerbations and requiring hospitalization due to acute exacerbations is higher in high-risk comorbidity and pulmonary comorbidities group (χ²=18.45, χ²=40.15, χ²=8.82, χ²=23.68). Multifactorial analysis showed that comorbid with asthma, lung cancer were risk factors for moderate-to-severe acute exacerbations, while asthma, bronchiectasis, lung cancer, and high COTE score were risk factors for patients requiring hospitalization due to acute exacerbations. The AUC for COTE > 5.5 and a combination of at least one pulmonary comorbidity as potential indication of moderate-to-severe acute exacerbations of COPD and hospitalization due to acute exacerbations was 0.667 (95% CI: 0.615, 0.719) and 0.740 (95% CI: 0.688, 0.792), respectively. The prediction models including COTE and pulmonary comorbidities can predict moderate-to-severe acute exacerbations (internal validation of AUC: 0.984, 95CI%: 0.964– 1) and hospitalization (internal validation of AUC: 0.978, 95CI%: 0.959– 0.998) of COPD.
Conclusion: COTE score and a combination of at least one pulmonary disease can predict the risk of moderate-to-severe acute exacerbations and hospitalization due to acute exacerbations in patients with COPD.

Keywords: acute exacerbation, chronic obstructive, comorbidity, hospitalization, pulmonary disease