It has been found that some patients with COVID-19 still show various degrees of abnormal chest imaging. However, there were few reports on the impacts of COVID-19 on pulmonary functions. Recently, the team of Zhong Nanshan and Li Shiyue of the First Affiliated Hospital of Guangzhou Medical University/Guangzhou Institute of Respiratory Health and the team of Lei Chunliang of Guangzhou the Eighth People’s Hospital jointly reported the pulmonary function characteristics of patients with COVID-19 at discharge. They found that some patients showed different degrees of impairment to lung functions, mainly pulmonary diffusion dysfunction followed by restrictive ventilation dysfunction. The impairment degree was related to the severity of illness during hospitalization.

A total of 110 patients with COVID-19 were included in the study, and accepted pulmonary function examination at discharge. The study found 51 cases (47.2%) with abnormal DLCO, 27 cases (25.0%) with abnormal total lung volume (TLC), 15 cases (13.6%) with abnormal forced expiratory volume (FEV1), 10 cases (9.1％) with abnormal forced vital capacity ( FVC), 5 cases (4.5％) with abnormal FEV1/ FVC and 8 cases (7.3％) with abnormal small airway function. There were significant differences in the proportion of abnormal lung diffusion functions between subgroups of different severity, 30.4% for mild, 42.4% for normal, and 84.2% for severe (p < 0.05); as the severity of the disease increased, the pulmonary diffusion function was affected more obviously. The expected TLC proportion of severe patients was much lower than that of mild or ordinary patients, which indicated that patients with severe pneumonia showed relatively more severe pulmonary dysfunctions.

The research results were published online in the European Respiratory Journal on May 7th. The first authors are Mo Xiaoneng, Jian Wenhua and Su Zhuquan, and the corresponding authors are Li Shiyue, Chen Ruchong and Zhong Nanshan. This study is the first one to summarize the pulmonary function characteristics of patients with COVID-19 at discharge, suggesting that pulmonary function examination should be included in the follow-up treatment for patients with COVID-19, especially for critically ill patients. At the same time, they proposed that pulmonary rehabilitation can also be used as a follow-up intervention measure.