Allergy and Asthma Patients Flock to Emergency Rooms

Warmer winters are driving up oak pollen, sending more people to the hospital

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The sneezing, watery eyes and runny noses from seasonal allergies are poised to land more people in the emergency room as temperatures rise, researchers have found.

In a study published online yesterday in GeoHealth, scientists reported that warmer winters resulting from climate change will lead to more intense pollen from oak trees, spelling more misery for allergy sufferers.

“We believe that this is a health risk that has been underappreciated and is likely worsening,” said lead author Susan Anenberg, an environmental scientist at Environmental Health Analytics LLC, a health research and consulting firm.


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Several previous studies have shown that allergy seasons are continually getting worse as pollen gradually emerges earlier each year with greater vigor and longer duration (Climatewire, Aug. 25, 2016).

Increased carbon dioxide levels around plants like ragweed also leads to greater pollen production. For allergy sufferers, this pollen can trigger an immune response ranging from mild symptoms like headaches to severe problems like difficulty breathing.

Anenberg and her team sought to quantify the impact of this alarming allergy accrual.

The researchers looked at emergency room visits related to asthma, a common allergy complication, stemming from exposure to pollen from oak trees. This already leads to more than 20,000 emergency room trips in the United States each year, mostly for children younger than 18, with damages estimated at $10.4 million.

“We picked oak pollen as a model simply because we had enough underlying data about how oak pollen is influenced by the climate,” Anenberg said.

The researchers calculated emergency room visits between 1994 and 2010 across the Midwest, Northeast and Southeast in the United States. They then projected how these patterns would change under different climate scenarios.

Under a severe warming scenario, the researchers found that emergency room visits could increase 10 percent by 2090 in the studied regions as oak pollen seasons grow. A moderate warming scenario would avert half of that increase.

Anenberg acknowledged that there are some limitations and uncertainties in the study. The analysis only looked at the eastern portion of the continental United States, so it’s unclear whether the trend would happen farther west.

The researchers were also unable to obtain baseline daily emergency room visit rates for some of the regions in the study, so they used an annual average that likely underestimated the daily rates during pollen season.

In addition, asthma is not the only allergy-related complication that lands people in hospitals; evidence shows that cardiovascular disease worsens with pollen exposure.

The population itself is also becoming more sensitized to pollen, and asthma rates are on the rise.

For these reasons, the results likely underestimate how many hospitalizations from allergies will result from climate change.

Anenberg said the next step is to conduct similar assessments in other regions. “We’d like to expand this beyond the eastern United States to other parts of the country and also around the world,” she said.

Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.

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