COVID-19-Induced Lung Gas-Exchange Damage Behind Long COVID Sleep Issues and Brain Changes
Nikhil Prasad Fact checked by:Thailand Medical News Team Nov 29, 2025 40 minutes ago
Medical News: A new study from researchers at the University of Iowa is helping to explain why many people continue to experience breathlessness, fatigue, sleep problems, and “brain fog” years after a COVID-19 infection. Using advanced lung and brain imaging, the team uncovered subtle but important links between reduced lung gas-exchange efficiency and changes in brain activity and sleep quality. These findings add to a growing body of evidence suggesting that lingering symptoms may be tied to a lung–brain pathway, and this
Medical News report highlights why this connection matters for millions still struggling with Long COVID.
Study links subtle lung gas-exchange problems with brain and sleep abnormalities in Long COVID patients
Why Standard Tests Miss the Problem
Although many Long COVID patients complain of breathing difficulties and ongoing cognitive issues, routine tests often show normal results. To examine this further, the scientists used a special imaging method called xenon-129 MRI, which can detect tiny abnormalities in lung gas exchange that traditional scans cannot. Participants also underwent brain MRI, cognitive assessments, and detailed symptom surveys nearly three years after their initial infection. The group included adults who continued to report fatigue, sleep problems, shortness of breath, and mental cloudiness long after recovering from the acute phase of the illness.
What the Researchers Found
The study revealed something unexpected. Overall lung function appeared normal when comparing Long COVID participants to healthy controls. However, within the Long COVID group, those with lower lung gas-exchange efficiency experienced more severe sleep disturbances, poorer performance on executive-function tasks, and higher cerebral perfusion on brain imaging. This means that the brain was receiving increased blood flow, possibly as a compensatory mechanism to counter reduced oxygen transfer in the lungs. These subtle associations were not visible on standard pulmonary tests, showing how small changes in lung function can still affect sleep and brain activity.
The Lung–Brain Link Becoming Clearer
The connections uncovered in the study point to a possible physiological chain reaction: when gas exchange in the lungs becomes less efficient, the brain may adjust blood flow to maintain oxygen availability. This may also disrupt sleep, which in turn worsens fatigue, concentration problems, and mental clarity. Interestingly, even though participants reported noticeable cognitive difficulties, most scored normally on objective cognition tests. This suggests that subjective “brain fog” may be influenced by fluctuating symptoms, sleep disruption, stress, or subtle neurological changes that short tests cannot fully detect.
What This Means for Long COVID Patients
These findings open new directions for understanding Long COVID. They suggest that gas-exchange issues in the lungs may continue long after infection, even when routine tests appear
normal. When combined with altered brain perfusion and poor sleep quality, these changes could help explain why symptoms persist for years. More research is needed with larger groups, including individuals who recovered without ongoing symptoms, to fully understand the lung–brain relationship. However, these early insights show that Long COVID is a multi-system condition and that both respiratory and neurological pathways may play important roles. Improving sleep, reducing inflammation, and monitoring lung microfunction may eventually guide better treatments that help patients regain quality of life.
The study findings were published in the peer reviewed journal: Scientific Reports.
https://www.nature.com/articles/s41598-025-26568-y
For the latest COVID-19 News, keep on logging to Thailand
Medical News.
Read Also:
https://www.thailandmedical.news/articles/coronavirus
https://www.thailandmedical.news/articles/long-covid
Share
Tweet
Share
