A breakthrough study reveals that rising temperatures and drier air due to global warming can lead to dehydration and inflammation in human airways. Researchers emphasize the need for proactive measures to mitigate these health risks.
A cross-institutional study partially funded by the National Institutes of Health indicates that global warming could lead to increased airway inflammation in humans. The researchers attribute this to the rising vapor pressure deficit (VPD), a measure of how much water the air can absorb, leading to dehydration, and subsequently, inflammation of the airways.
A higher VPD means greater water evaporation rates, thereby drying out ecosystems and, crucially, human airways. According to the study published today in the journal Communications Earth & Environment, exposure to dry air can cause dehydration and trigger the body’s inflammatory and immune responses, exacerbating conditions like asthma, allergic rhinitis and chronic cough.
“Air dryness is as critical to air quality as air dirtiness, and managing the hydration of our airways is as essential as managing their cleanliness,” lead author David Edwards, an adjunct professor of medicine at the Johns Hopkins University School of Medicine, said in a news release. “Our findings suggest that all mucosa exposed to the atmosphere, including ocular mucosa, are at risk in dehydrating atmospheres.”
The Research Process: Plant Behavior Mirrors Human Response
The researchers drew parallels between plant transpiration and the dehydration of mucus in the upper airways.
Plants suffer cellular damage from high transpiration rates, threatening their survival.
Similarly, when the human bronchial epithelium cells (lining the upper airway) were exposed to dry air, they demonstrated reduced mucus thickness and increased inflammatory proteins, known as cytokines.
Further investigation in animal models with healthy and pre-existing dry airways showed that mice exposed to intermittent dry air displayed significant inflammatory responses.
Implications and Future Risks
Based on climate models, the study predicts that the majority of the United States will face heightened risks of airway inflammation by the latter half of the century.
“This manuscript is a game changer for medicine, as human mucosa dehydration is currently a critical threat to human health, which will only increase as global warming continues,” added co-author Justin Hanes, the Lewis J. Ort Professor of Ophthalmology at the Wilmer Eye Institute, Johns Hopkins Medicine.
The researchers emphasized the importance of understanding how dry air impacts airway hydration to develop preventive or therapeutic interventions. Potentially, this could help mitigate or reverse the inflammatory effects of dehydration through effective behavioral changes or medical treatments.
A Call to Action
The study suggests a proactive approach to managing air dryness can help reduce the health risks associated with global warming. Collaboration among numerous institutions, such as Johns Hopkins University, Boston University, Imperial College London and others, underscores the global significance of this issue.
“Understanding how our airways dehydrate on exposure to dry air can help us avoid or reverse the inflammatory impact of dehydration by effective behavioral changes, and preventive or therapeutic interventions,” Edwards added.
Aurélie Edwards, Dan Li and Linying Wang of Boston University, Kian Fan Chung of Imperial College London, Deen Bhatta and Andreas Bilstein of Sensory Cloud Inc., Indika Endirisinghe and Britt Burton Freeman of Illinois Institute of Technology, and Mark Gutay, Alessandra Livraghi-Butrico and Brian Button of the University of North Carolina contributed to the study.
Source: Johns Hopkins Medicine