Long-term exposure to air pollution and lack of green spaces significantly increases the risk of hospitalization for respiratory conditions, according to new research presented at the European Respiratory Society (ERS) International Congress in Vienna this week.

Researchers from the University of Bergen, Norway, found that even in Northern Europe, where air pollution levels are relatively low, exposure to particulate matter, black carbon, and nitrogen dioxide increased the risk of respiratory hospitalization by 30-45% for each measured increase in these pollutants.

The team analyzed data from 1,644 people across five Northern European countries, using the European Community Respiratory Health Survey. They examined respiratory hospitalizations from 2000 to 2010 and evaluated their connection to long-term exposure to air pollutants and green spaces between 1990 and 2000. 

Researchers considered particulate matter, black carbon, nitrogen dioxide, ozone and “greenness” — a measure of vegetation near homes.

 “Air pollution causes persistent inflammation and oxidative stress in the respiratory system,” explained Shanshan Xu, lead researcher from the University of Bergen. “These harmful processes contribute to the development and exacerbation of chronic respiratory diseases, which can escalate into severe health episodes requiring hospital care.”

While access to green spaces led to a decrease in hospitalizations, researchers found it also increased emergency room visits, primarily among people with hay fever.

“It is also likely that long-term exposure to air pollution could lead to a decreased tolerance or increased sensitivity to these pollutants, explaining why even moderate or low levels might cause severe health effects in certain populations,” Xu said.

Traffic and air pollution

A second study led by researchers at the University of Leicester revealed a strong connection between traffic-related air pollution and the progression from asthma to chronic obstructive pulmonary disease (COPD). The study also found that higher exposure to nitrogen dioxide increases this risk, especially in individuals with a genetic predisposition.

“For every 10 micrograms per cubic meter higher exposure to particulate matter, the risk of developing COPD was 56% higher among asthmatic patients,” said lead author Dr Samuel Cai.

“People with asthma should always be aware of air pollution around them and, if necessary and resources allow, take measures such as wearing masks, use an indoor air purifier and reducing outdoor activities when air pollution is at high levels.”

The findings underscore the critical need for effective clean air initiatives and regulations, according to Professor Zorana J. Andersen, Chair of the ERS Health and Environment Committee.

“Air pollution affects everybody, but most people are very limited in the actions they can take against it to protect their health,” she stated. “It falls to policy-makers to come up with some bold actions to tackle air pollution in our cities.”

The power of laughter and genetics

The ERS Congress, which welcomed nearly 20,000 delegates onsite or online over five days, covered a wide range of respiratory health topics. Notable presentations included studies on genetic risk factors for asthma, the impact of medical clowns on pediatric pneumonia patients, and the effects of fine particulate matter on respiratory immune responses.

Researchers presented a new method for calculating a person’s genetic risk of developing asthma. The study, involving about 12,000 participants, successfully predicted asthma-related conditions, with particularly strong results for childhood-onset asthma.

“Using the power of genetics, we were able to predict asthma and asthma-related outcomes in individuals by generating polygenic risk scores,” Bernard S. Striker, the lead author, explained. “We also showed distinct, genetically driven pathways underlying asthma pathophysiology, which could contribute to personalized treatment approaches and risk mitigation.”

In an unconventional study showcasing the congress’s diverse research, scientists found an unexpected aid for children’s respiratory illnesses: laughter. The research on pediatric pneumonia treatment showed that medical clowns significantly reduced hospital stays for young patients.

Dr Karin Yaacoby-Bianu, a pediatric pulmonologist from the Carmel Medical Center in Israel, reported that children with pneumonia who received twice-daily visits from medical clowns during their first 48 hours of hospitalization had shorter hospital stays – 43.5 hours on average compared to 70 hours.

“Laughter and humor may also have direct physiological benefits by lowering respiratory and heart rates, reducing air trapping, modulating hormones, and enhancing the immune function,” Yaacoby-Bianu said.

The results also showed children supported by clowning required fewer days of intravenous antibiotics. While the study didn’t investigate specific mechanisms, Yaacoby-Bianu suggested that by alleviating stress, medical clowns may indirectly support the body’s natural defense mechanisms, potentially reducing the need for antibiotic interventions.

“We proved that laughter is good for health,” Yaacoby-Bianu told Bloomberg. “Every procedure you try to do with a clown is much easier, much nicer. The child forgets that he is in a hospital.”

The conference also highlighted growing concerns over fine particulate matter (PM2.5) and its impact on respiratory health. A comprehensive review examined how PM2.5 affects the respiratory immune system, suggesting that exposure significantly impairs immune cells’ response to microbial infections, potentially contributing to the development of severe respiratory diseases.

Among the hundreds of presentations in Vienna, other cutting-edge topics included the unique health dangers of wildfire smoke, AI-supported respiratory illness diagnoses and lung disease, and the effect of asthma on miscarriages.