Patients with severe asthma show structural brain changes and altered neural communication pathways linked to chronic inflammation.
RT’s Three Key Takeaways:
- Brain Structure Alterations: Patients with severe type-2 asthma showed less-organized white matter networks and size differences in the hippocampus and temporal lobes compared to patients with well-controlled asthma.
- Inflammation Link: Higher levels of type-2 inflammation were associated with greater structural variations in brain white matter across study participants.
- Reversibility Questions: Researchers are now examining whether targeted medical therapies that reduce airway inflammation can prevent or reverse these structural changes in the brain.
Individuals living with severe asthma exhibit measurable differences in the structure of their brains compared to individuals whose asthma is well controlled, according to research presented at ERS 2026.
The investigation, led by researchers from the National Institute for Health and Care Research (NIHR) Biomedical Research Centre: Bristol and City St George’s University of London in the UK, suggests that systemic inflammation driving severe respiratory disease can extend beyond the lungs to affect the central nervous system.
“Asthma is usually thought of as a disease of the lungs, but growing evidence suggests its effects may extend well beyond the airways,” said George Nava, NIHR academic clinical lecturer in the Bristol Academic Respiratory Unit, in a news release. “We wanted to investigate whether people with severe type-2 asthma show more differences in brain structure compared to those whose asthma is well controlled.”
Evaluating Brain White Matter and Neural Pathways
Severe type-2 asthma stems from an overactive immune response that causes persistent inflammation, frequent exacerbations, and breathing difficulties, with many patients remaining difficult to treat despite intensive medical management, according to the researchers.
To evaluate neurological effects, the research team recruited 50 patients with severe type-2 asthma and compared them with 25 patients with well-controlled mild or moderate type-2 asthma. All participants underwent magnetic resonance imaging (MRI) using quasi-diffusion imaging (QDI), an advanced imaging technique capable of mapping the microscopic organization of white matter pathways that carry signals between different brain regions.
The imaging revealed that patients with severe asthma had less-organized white matter networks than those with well-controlled disease, according to the study. Investigators also identified measurable volume differences in specific brain structures, including the hippocampus and the temporal lobes.
“We found measurable differences in brain structure in people with severe type-2 high asthma compared with people whose asthma was mild-moderate and well controlled,” said Nava. “Across all participants, higher levels of type-2 inflammation were associated with greater differences in brain white matter. While this study cannot prove that inflammation causes these changes, it does suggest there may be a biological link that deserves further investigation.”
Clinical Implications and Future Research
The research team is now tracking participants to examine whether these neurological variations shift after patients initiate targeted therapies designed to control severe type-2 inflammation, according to the presentation.
“One of the most important questions is whether these brain changes can be prevented or reversed,” said James Dodd, professor of respiratory medicine at the University of Bristol and chief investigator for the study. “We hope our ongoing work will help answer that.”
Independent experts highlighted the clinical importance of recognizing systemic manifestations of chronic pulmonary inflammation.
“We already know that asthma can have effects beyond the lungs, including impacts on memory, thinking and wellbeing,” said Apostolos Bossios, head of the ERS assembly on airway diseases, asthma, COPD, and chronic cough, and associate professor of respiratory medicine at the Karolinska Institutet.
Bossios noted in the release that type-2 asthma represents the most common phenotype, with approximately 5% to 10% of patients progressing to severe disease marked by ongoing symptoms, reduced quality of life, and frequent exacerbations despite high-intensity treatment.
“The chronic inflammation associated with asthma can negatively affect brain health,” said Bossios. “Studying how this inflammation is linked to changes elsewhere in the body could help us to understand the wider impact of the disease and help determine whether these changes can be prevented or reversed with treatment.”
