Recipient organisationNIHR Bristol Clinical Research Facility
NIHR supportRecorded as supported by this research centre
PeriodFeb 2025 — Jan 2027
In plain English
AI plain-English summary
Nearly 2 million people in the UK live with long COVID, and many of them struggle to breathe normally even when their lungs are clear. Doctors suspect the problem lies not in the lungs themselves but in a faulty breathing-control reflex triggered by small organs in the neck called the carotid bodies, which the COVID-19 virus can infect and disrupt. This study will test whether temporarily switching off that reflex—using a well-tolerated medicine called dopamine—can restore normal breathing in people with long COVID. The researchers will compare 27 patients with long COVID to 27 healthy volunteers, measuring breathing at rest and during exercise. If the approach works, it could lead to a new treatment for breathlessness that affects millions of people and costs the UK economy an estimated £8 billion each year. It would also confirm that long COVID breathing difficulties are a neurological reflex problem, not a lung disease—shifting how doctors diagnose and manage the condition. This is applied clinical research with a direct path to patient benefit.
View original technical description
Long-COVID is a condition in which people continue to have health problems for many months or years after a COVID-19 infection. It is a big health and economic problem in the UK, affecting nearly 2 million people and costing £8 billion each year. Many people with long-COVID experience ongoing breathing difficulties. They have a pattern of erratic breathing during exercise and even at rest, even though their lungs appear normal. We're not sure why this happens, but there is increasing evidence that this is due to disruption of the control of breathing, coordinated by the brain and nervous system, rather than a specific lung problem. A key part of this breathing control system is the carotid chemoreflex. This reflex is driven by small organs in the neck called the carotid bodies which monitor the chemical status of the blood, sending signals into the brain causing breathing and circulatory adjustments. The carotid chemoreflex, thus, controls breathing and feelings of breathlessness. When someone gets infected with the COVID-19 virus, the virus can get into the carotid bodies and disrupt their normal function. This could explain why some patients with long-COVID are breathless at rest and during exercise despite their lungs being normal. Our recent research shows that the carotid chemoreflex is more sensitive in people with long-COVID who don't have other health issues. This might be one of the reasons why they feel breathless and breathe too heavily during exercise.In this study we will temporarily “switch off” the carotid chemoreflex with a medicine called dopamine. We know that temporary use of dopamine does not cause many side-effects in people because it has been used extensively in people with and without health problems. We will recruit 27 people with Long covid and 27 healthy people. The results of the two groups will be compared to determine whether temporarily switching off the carotid chemoreflex improves breathing at rest and during exercise in people with long-COVID.
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know