Asthma is a significant noncommunicable disease in adults and children. The condition is the most common chronic disease in children.
The Asthma and Allergy Foundation of America (AAFA) notes that in the United States, nearly 26 million people — equal to 1 in 13 individuals — have asthma.
People with asthma experience symptoms including coughing, wheezing, shortness of breath, and a tight chest. These symptoms often result from an allergic or hypersensitivity reaction that causes spasms and mucus overproduction in the airways. This then leads to temporary obstructions.
This article discusses the global prevalence of asthma. It also details the causes, symptoms, and treatment of the condition.
A systematic analysis of the Global Burden of Disease published in
However, the
In the U.S.
The AAFA reports that nearly 26 million people in the U.S. have asthma. This number includes around 21 million adults ages 18 or older and around 4 million children under 18.
Black adults are the most likely population group to have asthma in the U.S. Female adults are more likely to have asthma than male adults — around 9.7% compared with 6.2%. Conversely, male children are more likely to have asthma than female children — around 7.3% compared with 5.6%.
Additionally, data from the
In the United Kingdom
The British Lung Foundation reports that more than 8 million people have a diagnosis of asthma in the U.K. This is equal to about 12% of the population.
While some may have grown out of the condition, 5.4 million currently receive asthma treatment.
Determining whether or not asthma is increasing may depend on where in the world researchers are calculating the number of people affected.
For instance, a
Additionally, the American Lung Association reports that asthma prevalence flattened out between 2010 and 2018, having been on the rise between 2001 and 2010.
However, there has still been a sharp increase in asthma prevalence since the 1960s.
Why is it increasing?
There is no definitive answer on why asthma is increasing. However, some researchers suggest a few potential reasons,
- increase in exposure to indoor allergens such as dust mites, cat hair, and fungi due to the modernization of housing with tighter insulation and plush furniture and carpets
- decrease in exposure to unhygienic environments in early life
- lack of exposure to beneficial bacteria, also known as microbial diversity
Doctors do not know the exact cause of asthma but are aware of the triggers that can irritate the airways of people with asthma.
These include:
- colds and flu
- allergies — for instance, to pollen, dust mites, or animal hair
- smoke, fumes, and pollution
- medication — particularly nonsteroidal anti-inflammatory drugs such as ibuprofen and aspirin
- emotional responses, such as stress or laughing
- sudden changes in temperature — for instance, cold air, wind, thunderstorms, heat, and humidity
- mold or damp
- exercise
Some people may develop asthma due to triggers in their working environment. For instance, they may work around chemicals, fumes, flour, or wood dust.
Certain factors can also increase a person’s risk of developing asthma, including:
- having an atopic condition such as eczema, a food allergy, or hay fever
- having a family history of asthma or atopic conditions
- having a lung infection called bronchiolitis as a child
- exposure to tobacco smoke as a child
- having a mother who smoked during pregnancy
- being premature — defined as being born before 37 weeks — or having a low birth weight
People with asthma usually have times when their asthma symptoms worsen, interspersed with times when they can breathe easily. The most common symptoms of asthma include:
- wheezing
- breathlessness
- a tight chest
- coughing
When a person has an asthma attack, their asthma symptoms worsen for a short period. This can happen suddenly or over the course of a few days.
A person having a severe asthma attack may:
- wheeze, cough, and develop severe and constant chest tightness
- become too breathless to eat, speak, or sleep
- breathe faster
- have a fast heartbeat
- feel drowsy, confused, exhausted, or dizzy
- have blue lips or fingers
- faint
No asthma treatments can currently cure the condition, but they can relieve a person’s symptoms and allow them to live a full life.
Available asthma treatments include:
- Inhalers: For example, reliever inhalers to alleviate the symptoms as they arise, preventer inhalers to stop symptoms from arising, or combination inhalers that do both.
- Oral tablets: For instance, leukotriene receptor antagonists or theophylline to stop the symptoms from developing, or steroids, which a person can either take to relieve the symptoms when they arise or stop them from developing.
- Biologic therapies: These are injections to help manage symptoms in people with severe asthma.
- Bronchial thermoplasty surgery: This may be an option for people with severe asthma. A surgeon passes a tube down the throat and into the lungs to apply heat to the muscles around the airways, which helps to stop them from narrowing.
Some people may also try complementary therapies, including breathing techniques such as Buteyko and the Papworth method, to help manage their asthma.
An average of 10 people die from asthma every day in the U.S., but almost all deaths from asthma are avoidable if people get the treatment they need.
Deaths from asthma increased for the first time in 20 years in 2020, and in 2021 3,517 people died from asthma.
The American Lung Association provides information on ways for people with asthma to find support to help them manage their condition.
Alongside its Lung HelpLine, the organization signposts people to support communities such as:
Asthma is a major noncommunicable disease in adults and children and the most common chronic disease in children. Asthma prevalence is higher today than it was before the 1960s.
However, research suggests that while the epidemic may be continuing in low- to middle-income countries, it may be subsiding in higher-income countries.
Doctors are not clear on the exact cause of asthma or why so many people develop the condition. However, they are aware of certain environmental triggers, such as animal fur, pollen, colds, and flu.