Study: Thunderstorms Linked to Rise in Asthma-Related Emergency Department Visits

Asthma-related emergency department (ED) visits rose significantly on thunderstorm days in Wichita, Kansas, according to data presented at the American College of Allergy, Asthma & Immunology (ACAAI) 2025 Annual Scientific Meeting. The authors wrote that their findings support storm-specific public health preparedness, including education and modifications to asthma action plans to ease health care burden and limit weather-related ED visits in this patient population.¹

How Does Weather Impact Patients With Asthma?

Asthma is a condition in which the airways narrow and swell and may produce extra mucus. This can make it difficult to breathe, trigger coughing, cause wheezing on exhalation, and lead to shortness of breath. Because asthma cannot be cured, it is crucial to effectively treat and manage its symptoms to improve quality of life.

For some, certain types of weather can trigger asthma symptoms. Extreme weather, such as high heat, cold weather, high humidity, and thunderstorms, can exacerbate an individual’s asthma symptoms.² Notably, climate change, air pollution, and exposure to smoke from wildfires have been shown to hinder the quality of life of patients with asthma and increase the number of asthma-related hospitalizations.^2-4

Thunderstorms’ Impact on Asthma and Related Symptoms

The authors refer to “thunderstorm asthma,” an environmental phenomenon marked by surges in asthma exacerbations during or shortly after storms. Although this idea has been documented internationally, few studies have evaluated this effect in US regions that have high allergen burdens. For this study, the investigators assessed whether thunderstorms are associated with increased asthma-related ED visits in Wichita, Kansas, and explores what demographics are impacted.¹

What Did the Study Evaluate?

The Ascension Health Institutional Review Board approved this study, which retrospectively analyzed 4439 asthma-related ED visits from January 1, 2020, to December 31, 2024, across 3 hospitals in Wichita. Thunderstorm days (n = 38) were identified using meteorological records from the National Centers for Environmental Information. Additionally, each ED visit was classified as occurring on a storm or nonstorm day. Daily asthma admissions were compared using a Mann-Whitney U test, and multivariable logistic regression assessed the relationship between storm day admissions and age, gender, zip code, and ED disposition.¹

Study Results

Of the 4439 asthma-related ED visits, approximately 14.1% (n = 627) occurred on 38 thunderstorm days. The mean number of admissions on storm days (17.91 visits) was significantly higher than those on nonstorm days (3.09 visits; Mann-Whitney U = 41,787.5; p < 5.55 × 10?²²). Despite the higher frequency of ED visits on storm days, they accounted for only 2% of calendar days but over 14% of asthma visits. Regression identified older age as a significant predictor of storm-day presentation (β = 0.0071, p = .002) whereas gender, zip code, and disposition were not observed to be significant.¹

“These results confirm that thunderstorms can pose a serious health risk for people with asthma, even in the United States,” lead study author Diala Merheb, MD said in a news release. “Because storms are unpredictable, patients and health care providers should include storm-specific precautions in asthma action plans.”⁵

What is the Pharmacist’s Role?

According to the Asthma and Allergy Foundation, when hard rain from thunderstorms hit pollen grains, it can break them up, make them smaller, and easier for people to inhale. The winds from storms will then carry pollen grains to where they can be inhaled in the lungs.²

“If you or your child has asthma, it’s smart to think about thunderstorms the same way you prepare for high-pollen days or cold weather. Understanding triggers and having a clear plan can help avoid emergency room visits,” study author Selina Gierer, DO, allergist and ACAAI member, said in the news release.⁵

Pharmacists play a critical role in helping patients with asthma prepare for thunderstorms and reduce the risk of ED visits. As highly accessible health care professionals, pharmacists can educate patients about “thunderstorm asthma,” reinforce the importance of controller medication adherence, and ensure patients have refills for rescue inhalers and spacers before severe weather. They can also review and update asthma action plans to include storm-specific precautions, such as remaining indoors during high-pollen or high-wind events, monitoring weather alerts, and recognizing early signs of exacerbation. Pharmacists can also counsel patients on proper inhaler technique, which is especially vital during sudden symptom flares, and help identify environmental allergens that may worsen during storms.

By providing real-time guidance, recommending preventive therapies, and collaborating with specialists and other health care professionals to adjust treatment plans when needed, pharmacists help patients better manage their asthma, avoid severe flare-ups, and ultimately prevent unnecessary ED visits during storm-related risk periods.

REFERENCES

1. Merheb D, Nguyen T, Gierer S, Chang H. Thunderstorm-associated increases in asthma ed visits in a midwestern us city: a five-year review. Ann Allergy Asthma Immunol. 2025;135(5, Supplement 1):S4. doi:10.1016/j.anai.2025.08.022

2. Asthma and Allergy Foundation. Asthma Triggers – Weather. Accessed November 26, 2025. https://aafa.org/asthma/asthma-triggers-causes/weather-triggers-asthma/

3. McGovern G. Air Pollution and Seasonal Variability Associated With Asthma- and COPD-Related Hospital Admissions. Pharmacy Times. January 20, 2025. Accessed November 26, 2025. https://www.pharmacytimes.com/view/air-pollution-and-seasonal-variability-associated-with-asthma--and-copd-related-hospital-admissions

4. Gerlach A. Wildfire Smoke Exposure Heightens Lung Cancer Risks and Complicates Patient Outcomes. Pharmacy Times. January 14, 2025. Accessed November 26, 2025. https://www.pharmacytimes.com/view/wildfire-smoke-exposure-heightens-lung-cancer-risks-and-complicates-patient-outcomes

5. American College of Allergy, Asthma, and Immunology. Thunderstorms linked to surge in asthma ER visits, new study shows. News release. November 6, 2025. Accessed November 26, 2025. https://www.eurekalert.org/news-releases/1103520