Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

To investigate whether the symptoms of ‘long-COVID’ are associated with any long-term damage that reduces the function of the lungs and respiratory system, a study led by University of Oxford researchers used a novel computational approach to assess how COVID-19 may affect long-term lung function.

A 3D render of Covid Virus

As a respiratory disease, COVID-19 infection mainly affects the lungs. While most people recover completely, a significant number of individuals experience symptoms that can persist for weeks or months post COVID infection, sometimes referred to as ‘long-COVID’. 

The results of the study assessing how COVID-19 may affect long-term lung function have just been published in the Journal of Applied Physiology. It was based on 178 participants who were grouped into four categories:

  1. Control participants, who had not had COVID-19.
  2. Those who had COVID-19 and were managed in the community.
  3. Those who were hospitalised with COVID-19 but not admitted to an intensive care unit (ICU).
  4. Those who were admitted to an ICU with severe COVID-19 and in most cases received invasive mechanical ventilation.

The participants were studied six months and twelve months after COVID-19 infection, using a novel computational approach to assess lung function.

Key findings:

  • Prior COVID-19 infection was associated with more uneven inflation of the lungs during normal breathing. This is something that is part of normal aging in the lung. The changes seen after COVID-19 in this study are roughly equivalent to those associated with 15 years of normal aging but are still much smaller than those seen in established lung disease.
  • There was an association between hospitalisation with COVID-19 and smaller lung volumes, but it is not known whether the smaller volumes are caused by COVID-19 infection, or instead represent a predisposing factor for more severe infection.
  • Admission to the ICU was associated with an enlarged respiratory dead space (the volume of gas that is breathed into the lungs but does not participate in gas exchange). This may have been caused by COVID-19 infection, but equally may have been caused by the process of mechanical ventilation.

The research team assessed lung function using a novel technique called computed cardiopulmonography. In this method, participants breathe through a mouthpiece connected to the measuring device that uses lasers to take highly precise measurements of gas composition. These measurements are then fed into a computational model of the respiratory and cardiovascular systems to estimate values for aspects relating to the individual’s lung function. For each individual, the model was adjusted to take into account physiological factors that can influence lung function, such as sex, age, height, and body mass.

This technique has already been shown capable of predicting whether patients with asthma required an increase in their medication. It also shows promise as a method to detect sub-clinical lung disease, opening the possibility of eventually treating patients earlier to prevent the onset of more significant disease.

Lead author Professor Peter Robbins, from the University of Oxford’s Department of Physiology, Anatomy and Genetics, said: ‘Our study illustrates the capability of this new technique to study aspects of lung function not so easily measured through standard clinical tests. However, without measurements prior to infection, it is not possible to conclude whether these differences result directly from COVID-19 infection, or whether they are actual risk factors associated with the lungs that predispose towards more serious disease.’

Respiratory Consultant Dr Nayia Petousi, from the University of Oxford’s Nuffield Department of Medicine, and one of the clinical leads for the study, said: ‘We hope that by providing insight into the understanding of post-COVID effects on the lungs the results can be of help in the clinical management of patients.’

Similar stories

New genetic mutation linked to rare conditions

Researchers from Wellcome Centre for Human Genetics at the Nuffield Department of Medicine, have discovered that a rare type of genetic variant can be responsible for two well-known skeletal disorders.

Essential research by COI improves understanding of COVID

Since the start of the pandemic, the CAMS-Oxford Institute (COI) has carried out 11 projects to better understand COVID-19, resulting in 21 published research articles.

Study opens a pathway to better diagnosis and treatment of autoimmune diseases

A study published in Nature by researchers from Washington University School of Medicine in St. Louis, Stanford University School of Medicine and Oxford University have developed a way to find the crucial protein fragment that drives autoimmunity, as well as the immune cells that respond to it.

Constant genetic surveillance needed to counter multidrug-resistant malaria strains

Continual monitoring of genetic changes in parasite populations is a powerful tool for analysing malaria outbreaks and identifying emerging multidrug-resistant malaria strains, say researchers from NDM’s Mahidol-Oxford Tropical Medicine Research Unit (MORU).

Lancet study informs WHO guidelines for the treatment of malaria in pregnancy

The study from the Worldwide Antimalarial Resistance Network (WWARN) provides compelling evidence that artemether-lumefantrine should now replace quinine as the treatment of choice in the first trimester.

Bacterial infections linked to one in eight global deaths, according to GRAM study

Data showing 7.7 million deaths from 33 bacterial infections can guide measures to strengthen health systems, particularly in low-income settings