Important facts
- Asthma is a major noncommunicable disease that affects both children and adults, and is the most common chronic disease among children.
- Inflammation and narrowing of the small airways in the lungs leads to asthma symptoms, which may come in the form of a combination of coughing, wheezing, shortness of breath, and chest tightness.
- Asthma affected an estimated 262 million people in 2019 (1), and caused 455,000 deaths.
- Inhaled medications can help control asthma symptoms and allow people with asthma to live normal, active lives.
- Avoiding asthma triggers can also help reduce symptoms of the disease.
- Most asthma-related deaths occur in low- and lower-middle-income countries, where underdiagnosis and undertreatment are a challenge.
- WHO is committed to improving diagnosis, treatment and monitoring of asthma to reduce the global burden of noncommunicable diseases and make progress towards universal health coverage.
Overview
Asthma is a chronic lung disease that affects people of all ages. It is caused by inflammation and contraction of the muscles surrounding the bronchial tubes, making breathing more difficult.
Symptoms can include coughing, wheezing, shortness of breath and chest tightness. These symptoms can be mild or severe, and may come and go over time.
Although asthma can be a serious condition, it can be managed with the right treatment. People with asthma symptoms should talk to a health professional.
Impact of disease
Asthma is often underdiagnosed and undertreated, especially in low- and middle-income countries.
People with insufficiently treated asthma can suffer from sleep disturbances, daytime fatigue, and poor concentration. People with asthma and their families may miss school and work, financially affecting the family and the wider community. If symptoms are severe, people with asthma may need to receive emergency health care and may be hospitalized for treatment and monitoring. In severe cases, asthma can lead to death.
Symptoms
Asthma symptoms can vary from person to person, and sometimes the symptoms worsen significantly, known as an asthma attack. Symptoms are often worse at night or during exercise.
Common symptoms of asthma include:
- Persistent cough, especially at night
- Wheezing when exhaling, and sometimes when inhaling
- Shortness or difficulty breathing, sometimes even while resting
- Chest tightness, making deep breathing difficult.
Some people experience worse symptoms when they have a cold or during weather changes. Other irritants include dust, smoke, fumes, grass and tree pollen, animal fur, feathers, strong-smelling soaps, and perfumes.
Symptoms can be caused by other conditions as well. People with symptoms should talk to a health care provider.
The causes of disease
Many factors have been linked to an increased risk of asthma, although it is often difficult to pinpoint a single direct cause.
- The likelihood of developing asthma increases if other members of the family also have asthma - especially a close relative, such as a parent or sibling.
- People with other allergic conditions, such as eczema and rhinitis (hay fever), are more likely to develop asthma.
- Urbanization is associated with an increased prevalence of asthma, possibly due to multiple lifestyle factors.
- Some events that affect an individual at an early age affect the developing lungs and may increase the risk of developing asthma. These events include low birth weight, premature birth, exposure to tobacco smoke and other sources of air pollution, and viral respiratory infections.
- Exposure to a range of environmental allergens and irritants is also thought to increase the risk of asthma, including indoor and outdoor air pollution, house dust mites, mold, and on-the-job exposure to chemicals, fumes or dust.
- Children and adults who are overweight or obese have a greater risk of developing asthma.
treatment
Asthma cannot be cured, but there are many treatments available. The most common treatment is the use of an asthma inhaler, which delivers the medicine directly to the lungs.
Asthma sprays can help control the disease and enable people with asthma to live a normal, active life.
There are two main types of asthma inhalers:
- Bronchodilators (eg salbutamol), which open the airways and relieve symptoms;
- Steroids (such as beclometasone) that reduce inflammation of the airways, relieving asthma symptoms and reducing the risk of severe asthma attacks and death.
People with asthma may need to use an asthma inhaler daily. Their treatment will depend on the frequency of symptoms and the types of asthma inhalers available.
Asthma inhalers can be difficult to use, especially for children and during emergencies. Using a spacer device will make it easier to use the sprayer. This helps deliver the medicine to the lungs more easily. The spacer is a plastic container with a mouthpiece or mask at one end and a hole that connects to the sprayer at the other end. A home-made spacer from a 500 ml plastic bottle can be just as effective as a commercially manufactured spacer.
Access to asthma inhalers is a problem in many countries. In 2021, bronchodilators were available in public primary health care facilities in half of low- and lower-middle-income countries, and steroid inhalers were available in a third of these countries.
It is also important to raise community awareness to reduce myths and stigmatizing practices associated with asthma in some settings.
Self-care
People with asthma and their families should be educated to understand more about their asthma. This includes their treatment options, irritants to avoid, and how to manage their symptoms at home.
It is important for people with asthma to know how to increase their dose of treatment when their symptoms get worse to avoid having a serious attack. Health care providers may give people with asthma an action plan to help them get more control of their treatment.