What is Asthma?

Asthma is a chronic (long-term) condition affecting people of all ages, causing changes to the airways of the lungs.^1,2 There is always some degree of swelling in the lungs with asthma, however, this can worsen, which is called a flare.² During a flare, swelling from inflammation, increased thick mucus production, and tightening of the muscles around small airways causes airway narrowing, making it harder to breathe.^1-3 Untreated or poorly controlled asthma can result in scarring of the lungs, called airway remodeling.² When this occurs, asthma treatments may not work as well and breathing can remain difficult.²

Allergic asthma is the most common type of asthma; it typically starts in childhood, and is often present along with eczema and allergic rhinitis (hayfever).⁴ Airborne allergens that are inhaled help drive the inflammatory process and asthma symptoms.⁴ Allergic asthma often continues on into adulthood, and flares with the change in seasons is more likely.⁴

Rapid Facts on Asthma in Children and Adults

According to the Centers for Disease Control and Prevention (CDC), 1 in 13 people in the US has asthma.³ Current rates of asthma in adults in children include⁵
- 8.7% of adults (age 18 and older)
- 6.2% of children (younger than age 18)
Annual number of physician office visits for asthma: 4.9 million⁵
Number of emergency department visits for asthma (not including chronic obstructive asthma): 939,000⁵
Number of deaths from asthma (in 2021): 3,517⁵
Low income is linked to asthma prevalence, exacerbations, hospitalizations, and intensive care unit admission⁵
In addition to low income, inequities in wealth, homeownership, level of education, and employment opportunities contribute to asthma disparities⁶
Black and Latino Americans have a higher asthma rates of asthma and are at greater risk for death from asthma-related causes^6,7

References

World Health Organization (WHO). Asthma. 5/4/23. https://www.who.int/news-room/fact-sheets/detail/asthma
American Lung Association (ALA). What is asthma? Last updated 4/19/23. https://www.lung.org/lung-health-diseases/lung-disease-lookup/asthma/learn-about-asthma/what-is-asthma
National Institutes of Health (NIH). National Heart, Lung, and Blood Institute (NHLBI). LMBB: What is asthma? 3/2020. https://www.nhlbi.nih.gov/resources/lmbb-what-asthma-fact-sheet
Global Initiative for Asthma. Global Strategy for Asthma Management and Prevention, 2023. Updated July, 2023. Available from: www.ginasthma.org.
Centers for Disease Control and Prevention. National Center for Healthcare Statistics. Asthma. https://www.cdc.gov/nchs/fastats/asthma.htm
Grant T, et al. Asthma and the social determinants of health. Ann Allergy Asthma Immunol. 2022;128:5-11. https://www.annallergy.org/article/S1081-1206(21)01132-7/fulltext
NIH/NHLBI. Asthma: Causes and triggers. Last updated 3/24/22. https://www.nhlbi.nih.gov/health/asthma/causes

All URLs accessed 1/24/24.