This commentary refers to ‘Association of beta-blocker use with survival and pulmonary function in patients with chronic obstructive pulmonary and cardiovascular disease: a systematic review and meta-analysis’ by Yang et al., 2020;41:4415–4422 and the discussion piece ‘β-Blocker and survival and pulmonary function in patients with chronic obstructive pulmonary and cardiovascular disease’, by H. Tang et al., 2021;42:1180.
First, regarding the ‘inclusion criteria’, we included retrospective studies, the data sources were all from databases. They included patients with chronic obstructive pulmonary disease (COPD) based on the medical record, use of medications, and prior admissions. COPD is a very complex disease with different disease phenotypes and overlaps with other diseases. In the past 2 years, Global Strategy for the Diagnosis, Management and Prevention of Chronic Obstructive Pulmonary Disease (GOLD)1 and Global Strategy for Asthma Management and Prevention (GINA)2 have jointly recommended the concept of Asthma COPD Overlap Syndrome (ACO),3 which is used to describe a patient who has characteristics of both COPD and asthma. Patients with ACO have persistent airway obstruction. There are two phenotypes of bronchial inflammation (Th1 and Th2) in the airway of one patient. Their clinical features are consistent with both asthma and COPD. All of the above is not the focus of this study. This article focuses on the problem of insufficient prescription of β-blockers in patients with COPD. One of the fundamental issues is the concern regarding β-blockers and associated airway smooth muscle constriction. However, it is impossible to distinguish asthma from COPD in some retrospective studies. Considering that these patients have the characteristics of COPD, we still included these studies pointed out by Dr Yang.
Second, regarding ‘Some hazard ratios shown in the forest plots were inconsistent with the data provided in the original articles’, The values of hazard ratio in Gottlieb 1998 and Hawkins 2009 were all obtained from the Kaplan–Meier plots in the original study using methods suggested by Tierney et al.4
Finally, regarding ‘inconsistencies found between different sections of the SR’, Dr Yang and colleagues5 are right, we will contact the magazine to make corrections. We regret the errors. Overall, the final results and conclusions did not change substantially.
Conflict of interest: none declared.
Contributor Information
Yan-Li Yang, Department of Respiratory and Critical Care Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
Zi-Jian Xiang, Technical department, Beijing Zhiyun Data Technology Co. Ltd, No. 1397, New Materials Chuangye Building, 7 Fenghui Zhong Lu, Haidian District, Beijing 100094, China.
Jing-Hua Yang, Technical department, Beijing Zhiyun Data Technology Co. Ltd, No. 1397, New Materials Chuangye Building, 7 Fenghui Zhong Lu, Haidian District, Beijing 100094, China.
Wen-Jie Wang, Technical department, Beijing Zhiyun Data Technology Co. Ltd, No. 1397, New Materials Chuangye Building, 7 Fenghui Zhong Lu, Haidian District, Beijing 100094, China.
Zhi-Chun Xu, Technical department, Beijing Zhiyun Data Technology Co. Ltd, No. 1397, New Materials Chuangye Building, 7 Fenghui Zhong Lu, Haidian District, Beijing 100094, China.
Ruo-Lan Xiang, Department of Physiology and Pathophysiology, Peking University School of Basic Medical Sciences, No.38 Xueyuan Road, Haidian District, Beijing 100191, China.
References
- 1.Global Strategy for the Diagnosis, Management and Prevention of Chronic Obstructive Pulmonary Disease (GOLD) 2021. https://goldcopd.org/ (27 December 2020).
- 2.Global Strategy for Asthma Management and Prevention (2020. update). https://ginasthma.org/ (27 December 2020)
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- 5. Yang Y-L, Xiang Z-J, Yang J-H, Wang W-J, Xu Z-C, Xiang R-L. Association of β-blocker use with survival and pulmonary function in patients with chronic obstructive pulmonary and cardiovascular disease: a systematic review and meta-analysis. European Heart Journal 2020;41:4415–4422. [DOI] [PMC free article] [PubMed] [Google Scholar]