Skip to main content

Main menu

  • Home
  • Current issue
  • ERJ Early View
  • Past issues
  • For authors
    • Instructions for authors
    • Submit a manuscript
    • Author FAQs
    • Open access
    • COVID-19 submission information
  • Alerts
  • Podcasts
  • Subscriptions
  • ERS Publications
    • European Respiratory Journal
    • ERJ Open Research
    • European Respiratory Review
    • Breathe
    • ERS Books
    • ERS publications home

User menu

  • Log in
  • Subscribe
  • Contact Us
  • My Cart

Search

  • Advanced search
  • ERS Publications
    • European Respiratory Journal
    • ERJ Open Research
    • European Respiratory Review
    • Breathe
    • ERS Books
    • ERS publications home

Login

European Respiratory Society

Advanced Search

  • Home
  • Current issue
  • ERJ Early View
  • Past issues
  • For authors
    • Instructions for authors
    • Submit a manuscript
    • Author FAQs
    • Open access
    • COVID-19 submission information
  • Alerts
  • Podcasts
  • Subscriptions

Abnormal pulmonary function in COVID-19 patients at time of hospital discharge

Xiaoneng Mo, Wenhua Jian, Zhuquan Su, Mu Chen, Hui Peng, Ping Peng, Chunliang Lei, Shiyue Li, Ruchong Chen, Nanshan Zhong
European Respiratory Journal 2020; DOI: 10.1183/13993003.01217-2020
Xiaoneng Mo
1Department of Respiratory medicine, Guangzhou Eighth People's Hospital, Guangzhou, China
4Drs Mo, Jian and Su are joint first authors
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Wenhua Jian
2China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
4Drs Mo, Jian and Su are joint first authors
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Zhuquan Su
2China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
4Drs Mo, Jian and Su are joint first authors
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Mu Chen
1Department of Respiratory medicine, Guangzhou Eighth People's Hospital, Guangzhou, China
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Hui Peng
2China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Ping Peng
2China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Chunliang Lei
3Department of hepatology, Guangzhou Eighth People's Hospital, Guangzhou, China
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Shiyue Li
2China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Ruchong Chen
2China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Nanshan Zhong
2China State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Data
  • Info & Metrics
  • PDF
Loading

Abstract

In discharged survivors with COVID-19, impairment of diffusion capacity is the most common abnormality of lung function followed by restrictive ventilatory defect, which are both associated with the severity of the disease. Pulmonary function test (not onl

To the editors

On the 11th of March 2020, the World Health Organisation(WHO) declared the Coronavirus Disease 2019 (COVID-19) as a pandemic. As of 22 April, more than 2.4 million cases have been confirmed worldwide [1]. In light of the widely documented lung injuries related with COVID-19 [2–3], concerns are raised regarding the assessment of the lung injury for discharged patients. A recent report portrayed that discharged patients with COVID-19 pneumonia are still having residual abnormalities in chest CT scans, with ground-glass opacity as the most common pattern [4]. Persistent impairment of pulmonary function and exercise capacity have been known to last for months or even years [5–8] in the recovered survivors with other coronavirus pneumonia (severe acute respiratory syndrome/SARS and middle east respiratory syndrome/MERS). However, until now, there is no report in regard to pulmonary function in discharged COVID-19 survivors. Our manuscript aims to describe the characteristics of pulmonary function in these subjects.

We recruited laboratory confirmed non-critical COVID-19 cases, from February 5th to March 17th from admitted patients. According to the WHO interim guidance [9] and the guidance from china [10], disease severity were categorised as mild illness(mild symptoms without radiographic appearance of pneumonia), pneumonia(having symptoms and the radiographic evidence of pneumonia, with no requirement for supplemental oxygen), severe pneumonia(having pneumonia, including one of the following: respiratory rate>30 breaths/min; severe respiratory distress; or SpO2≤93% on room air at rest), and critical cases (e.g. respiratory failure requiring mechanical ventilation, Septic shock, other organ failure occurrence or admission into the ICU). Critical cases were excluded from our study. Spirometry and pulmonary diffusion capacity test (Cosmed PFT Quark, Rome, Italy) were performed following the ATS-ERS guidelines on the day of or 1 day before discharge. To minimise cross infections, carbon monoxide diffusion capacity (DLCO) was measured by the single-breath method. Written informed consent was obtained from all patients, and the study was approved by the ethics committee of The Guangzhou Eighth People's Hospital.

One-hundred and ten discharged cases were recruited, which included 24 cases of mild illness, 67 cases of pneumonia and 19 cases of severe pneumonia (table 1). The mean age of these cases was 49.1 years and fifty-five of them were females. Forty-four (40%) patients had at least one underlying comorbidity, of which 23.6% had hypertension and 8.2% had diabetes. Only 3 patients (2.7%) were reported having chronic respiratory diseases (one patient with asthma, one with chronic bronchitis and one with bronchiectasis). No significant differences were found among the three groups of cases, in the relation to gender, smoking status, underlying disease and the BMI value. The duration from onset of disease to pulmonary function test was 20±6 days in cases with mild illness, 29±8 days in cases with pneumonia and 34±7 days in cases that presented severe pneumonia. On the day of discharge, the SpO2% on room air at rest was normal in all subjects and no significant difference was found among the different groups (all p>0.05).

View this table:
  • View inline
  • View popup
TABLE 1

Demography and pulmonary function characteristics of discharged patients with COVID-19

Spirometry was uneventfully completed in all patients, except for two failed diffusion capacity tests. Anomalies were noted in DLCO% in 51 cases (47.2%), total lung capacity (TLC)% in 27 (25.0%), forced expiratory volume in the first second (FEV1)% in 15 (13.6%), forced vital capacity (FVC) % in 10 (9.1%), FEV1/FVC in 5 (4.5%), and small airway function in 8 (7.3%). Table 1 shows a significant difference in impaired diffusing-capacity among the different groups of severity, which accounted for 30.4% in mild illness, 42.4% in pneumonia and 84.2% in severe pneumonia, respectively(p<0.05). This trend of the gradual decrease in level of DLCO among patients was identical with the varying degree of severity. For about half (25/51) of the DLCO-impaired patients, the DLCO corrected for alveolar volume (DLCO/VA) was still within the normal range, which might indicate that DLCO decrease was more than the DLCO/VA in recovered subjects. The value of TLC % predicted in severe pneumonia cases was much less than that of pneumonia or mild illness, suggesting higher impairment of lung volume in severe cases. There was no significant difference among the discharged survivors with different severity in regard to other ventilatory defects (e.g. FEV1, FVC, FEV1/FVC).

Recent studies reveal that the lung is the most affected organ by COVID-19 [2, 3], with pathologies that include diffuse alveolar epithelium destruction, capillary damage/bleeding, hyaline membrane formation, alveolar septal fibrous proliferation, and pulmonary consolidation. Previous studies have demonstrated that the recovered patients with coronavirus pneumonia can be left with damaged lungs. Impaired lung function was common and could last for months or even years. In the follow-up studies lasting from half a year to 2 years in the rehabilitating SARS patients [5–7], impaired DLCO was the most common abnormality, ranging from 15.5% to 43.6%, followed by defected TLC, ranging from 5.2% to 10.9%. Wan et.al showed that 37% of MERS survivors still presented with an impairment of DLCO, but normal TLC at 12 months [8]. Our study seems to be more consistent with the findings in SARS. Interestingly, in our study, the greater decline in DLCO versus DLCO/VA suggests that diffusion membrane may be more causative of the pulmonary dysfunction compared to lowered lung volume. The low proportion and severity of small airway dysfunction in our cohort also suggests that COVID-19 is more likely associated with diffuse lung epithelial damage and small airway congestion. when evaluating lung fibrotic changes in SARS, the Dynamic DLCO scores were found more sensitive than HRCT [11]. Whether survivors of COVID-19 with impairment of DLCO or residual abnormalities of chest CT will develop pulmonary fibrosis requires further investigation.

There are limitations in our study. Firstly, the lack of the baseline PFT results prior to the illness make it difficult to make a comparison with the results after the illness. there are only a minority of patients having chronic respiratory disease, it should be acceptable to speculate that the basic lung function in majority of patients would be normal. The interpretation regarding to the impact of the COVID-19 on lung function remain valid. Secondly, the association between CT image and the lung function parameter wasn't analysed in our study. Finally, this cross-sectional analysis only provides a short follow-up, the long-term dynamic variation of the lung function after hospital discharge still require further investigation.

In conclusion, our study firstly reveals that, in discharged survivors with COVID-19, impairment of diffusion capacity is the most common abnormality of lung function followed by restrictive ventilatory defect, which are both associated with the severity of the disease. Pulmonary function test (not only spirometry, but also diffusion capacity) should be considered to performed in routine clinical follow-up for certain recovered survivors, especially in severe cases. Subsequent pulmonary rehabilitation might be considered as an optional strategy. Long-term studies are needed to address whether these deficits are persistent.

Acknowledgement

We thank the hospital staffs for their efforts in collecting the data. We also thank Weijie Guan, MD, Yi Gao, MD, Zhe Zhang, MD, Jinping Zheng, MD and Guangqiao Zeng, MD (First affiliated hospital of Guangzhou Medical University) for critical opinion. None of these individuals received compensation for their contributions.

Footnotes

  • Author Contributions: Drs S Li, R Chen and N Zhong contributed equally as senior authors. Drs S Li, R Chen and N Zhong had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

  • Concept and design: X Mo, R Chen, S Li.

  • Acquisition, analysis, or interpretation of data: X Mo, W Jian, Z Su, M Chen, H Peng, P Peng, C Lei, R Chen, S Li

  • Drafting of the manuscript: X Mo, W Jian, Z Su, R Chen

  • Critical revision of the manuscript for important intellectual content: C Lei, N Zhong

  • Support statement: The study funders/sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

  • Conflict of interest: Dr. Mo has nothing to disclose.

  • Conflict of interest: Dr. Jian has nothing to disclose.

  • Conflict of interest: Dr. Su has nothing to disclose.

  • Conflict of interest: Dr. Chen has nothing to disclose.

  • Conflict of interest: Dr. Peng has nothing to disclose.

  • Conflict of interest: Dr. Peng has nothing to disclose.

  • Conflict of interest: Dr. Lei has nothing to disclose.

  • Conflict of interest: Dr. Li has nothing to disclose.

  • Conflict of interest: Dr. Chen has nothing to disclose.

  • Conflict of interest: Dr. Zhong has nothing to disclose.

  • Received April 16, 2020.
  • Accepted April 27, 2020.
  • Copyright ©ERS 2020
http://creativecommons.org/licenses/by-nc/4.0/

This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial Licence 4.0.

References

  1. ↵
    1. World Health Organization
    . Coronavirus disease (COVID-19) Situation Report-93. www.who.int/docs/default-source/coronaviruse/situation-reports/20200422-sitrep-93-covid-19.pdf?sfvrsn=35cf80d7_4. Accessed April 22, 2020.
  2. ↵
    1. Zhou F,
    2. Yu T,
    3. Du R, et al.
    Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. Lancet 2020; 395: 1054–1062. doi:10.1016/S0140-6736(20)30566-3
    OpenUrlCrossRefPubMed
  3. ↵
    1. Xu Z,
    2. Shi L,
    3. Wang YJ, et al.
    Pathological findings of COVID-19 associated with acute respiratory distress syndrome. Lancet Respir Med 2020; 8: 420–422. doi:10.1016/S2213-2600(20)30076-X
    OpenUrlPubMed
  4. ↵
    1. Wang YH,
    2. Dong CJ,
    3. Hu Y, et al.
    Temporal Changes of CT Findings in 90 Patients with COVID-19 Pneumonia: A Longitudinal Study. Radiology 2020; 200843. doi:10.1148/radiol.2020200843
  5. ↵
    1. Hui DS,
    2. Joynt GM,
    3. Wong KT, et al.
    Impact of severe acute respiratory syndrome (SARS) on pulmonary function, functional capacity and quality of life in a cohort of survivors. Thorax 2005; 60: 401–409. doi:10.1136/thx.2004.030205
    OpenUrlAbstract/FREE Full Text
    1. Hui DS,
    2. Wong KT,
    3. Ko FW, et al.
    The 1-year impact of severe acute respiratory syndrome on pulmonary function, exercise capacity, and quality of life in a cohort of survivors. Chest 2005; 128: 2247–2261. doi:10.1378/chest.128.4.2247
    OpenUrlCrossRefPubMedWeb of Science
  6. ↵
    1. Ngai JC,
    2. Ko FW,
    3. Ng SS, et al.
    The long-term impact of severe acute respiratory syndrome on pulmonary function, exercise capacity and health status. Respirology 2010; 15: 543–550. doi:10.1111/j.1440-1843.2010.01720.x
    OpenUrlCrossRefPubMed
  7. ↵
    1. Park WB,
    2. Jun KI,
    3. Kim G, et al.
    Correlation between Pneumonia Severity and Pulmonary Complications in Middle East Respiratory Syndrome. J Korean Med Sci 2018; 33: e169. doi:10.3346/jkms.2018.33.e169
    OpenUrl
  8. ↵
    Clinical management of severe acute respiratory infection when COVID-19 is suspected. Released by World Health Organization on 13 March 2020. www.who.int/publications-detail/clinical-management-of-severe-acute-respiratory-infection-when-novel-coronavirus-(ncov)-infection-is-suspected
  9. ↵
    Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia (Trial Version 7). Released by National Health Commission & State Administration of Traditional Chinese Medicine on March 3, 2020. www.who.int/docs/default-source/wpro---documents/countries/china/covid-19-briefing-nhc/1-clinical-protocols-for-the-diagnosis-and-treatment-of-covid-19-v7.pdf?sfvrsn=c6cbfba4_2
  10. ↵
    1. Xie L,
    2. Liu Y,
    3. Xiao Y, et al.
    Follow-up study on pulmonary function and lung radiographic changes in rehabilitating severe acute respiratory syndrome patients after discharge. Chest 2005; 127: 2119–2124. doi:10.1378/chest.127.6.2119
    OpenUrlCrossRefPubMed
PreviousNext
Back to top
View this article with LENS
Vol 57 Issue 2 Table of Contents
European Respiratory Journal: 57 (2)
  • Table of Contents
  • Index by author
Email

Thank you for your interest in spreading the word on European Respiratory Society .

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Abnormal pulmonary function in COVID-19 patients at time of hospital discharge
(Your Name) has sent you a message from European Respiratory Society
(Your Name) thought you would like to see the European Respiratory Society web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Print
Alerts
Sign In to Email Alerts with your Email Address
Citation Tools
Abnormal pulmonary function in COVID-19 patients at time of hospital discharge
Xiaoneng Mo, Wenhua Jian, Zhuquan Su, Mu Chen, Hui Peng, Ping Peng, Chunliang Lei, Shiyue Li, Ruchong Chen, Nanshan Zhong
European Respiratory Journal Jan 2020, 2001217; DOI: 10.1183/13993003.01217-2020

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero

Share
Abnormal pulmonary function in COVID-19 patients at time of hospital discharge
Xiaoneng Mo, Wenhua Jian, Zhuquan Su, Mu Chen, Hui Peng, Ping Peng, Chunliang Lei, Shiyue Li, Ruchong Chen, Nanshan Zhong
European Respiratory Journal Jan 2020, 2001217; DOI: 10.1183/13993003.01217-2020
del.icio.us logo Digg logo Reddit logo Technorati logo Twitter logo CiteULike logo Connotea logo Facebook logo Google logo Mendeley logo
Full Text (PDF)

Jump To

  • Article
    • Abstract
    • To the editors
    • Acknowledgement
    • Footnotes
    • References
  • Figures & Data
  • Info & Metrics
  • PDF
  • Tweet Widget
  • Facebook Like
  • Google Plus One

More in this TOC Section

  • Effect of corrected GLI reference equations on carbon monoxide transfer factor interpretation
  • Head-to-head comparison of SARS-CoV-2 antigen-detecting rapid test with self-collected nasal swab versus professional-collected nasopharyngeal swab
  • Single-cell RNA sequencing identifies macrophage transcriptional heterogeneities in granulomatous diseases
Show more Research letter

Related Articles

Navigate

  • Home
  • Current issue
  • Archive

About the ERJ

  • Journal information
  • Editorial board
  • Reviewers
  • CME
  • Press
  • Permissions and reprints
  • Advertising

The European Respiratory Society

  • Society home
  • myERS
  • Privacy policy
  • Accessibility

ERS publications

  • European Respiratory Journal
  • ERJ Open Research
  • European Respiratory Review
  • Breathe
  • ERS books online
  • ERS Bookshop

Help

  • Feedback

For authors

  • Instructions for authors
  • Submit a manuscript
  • ERS author centre

For readers

  • Alerts
  • Subjects
  • Podcasts
  • RSS

Subscriptions

  • Accessing the ERS publications

Contact us

European Respiratory Society
442 Glossop Road
Sheffield S10 2PX
United Kingdom
Tel: +44 114 2672860
Email: journals@ersnet.org

ISSN

Print ISSN:  0903-1936
Online ISSN: 1399-3003

Copyright © 2021 by the European Respiratory Society