Key takeaways
- Asthma involves inflammation and constriction of the airways, making them overly sensitive to various triggers like pollen, smoke, or even cold air.
- While the exact causes of asthma are not fully understood, a combination of genetic predisposition, childhood infections, and early allergen exposure might play a role.
- Doctors use lung function tests, such as peak flow and spirometry, and allergy testing to diagnose asthma and identify potential allergic triggers.
Asthma is a chronic disease that affects the air passages in the lungs. No single cause has been identified, but several factors may contribute to its development:
- family history, though no specific “asthma gene” has been found
- childhood viral infections, such as respiratory infections
- early exposure to allergens
Despite ongoing research, the reason why some people develop asthma while others don’t is unclear. Allergies frequently occur alongside asthma, but not everyone with allergies develops asthma.
While asthma causes are unknown, doctors have identified the leading causes of asthma symptoms.
According to the
While asthma is prevalent in both developed and developing nations, WHO states that most asthma-related deaths occur in low- and middle-income countries. This disparity likely stems from limited awareness about the condition and restricted access to treatments.
When you have asthma, the lining of your airways becomes inflamed and swollen. This inflammation makes your air passages especially sensitive to irritants and asthma triggers.
The swelling can also narrow your airways, restricting airflow and making it difficult for air to move through them. As a result, you experience difficulty breathing both in and out.
When airways come into contact with asthma triggers, the surrounding muscles contract.
This causes the air passages to become even narrower, giving you a tight feeling in the chest like a rope is being tightened around it. Mucus can get lodged in the narrowed airways, causing more breathing difficulties.
Asthma triggers vary from person to person. When airways encounter these triggers, they become inflamed, constrict, and fill with mucus. The airway lining may swell, causing the passage to narrow.
Asthma triggers include:
- pollen
- dust mites or cockroaches
- mold
- fireplaces
- pet hair or dander
- changes in weather, especially cold air
- respiratory infections such as the common cold
- tobacco smoke
- stress and strong emotions
- hormonal fluctuations
- exercise and physical activity (exercise-induced asthma)
- allergic reaction to certain foods, such as eggs, nuts, and milk
- sulfites and food preservatives
- heartburn or acid reflux
- certain medications, such as beta-blockers, aspirin (Bayer), and ibuprofen (Advil, Motrin)
- unfavorable air quality that is high in nitric oxide, ozone, and sulfur dioxide gases
- chemicals and fragrances
Depending on how severe your asthma is, you might experience symptoms long term or only when you encounter triggers. Symptoms typically worsen at night.
Allergies are widely considered a possible cause of asthma. When allergies trigger asthma symptoms, the condition is called allergic asthma.
Substances that cause your allergic reactions can also prompt asthma symptoms. For instance, if you have seasonal pollen allergies, you might experience worsened asthma during those times of year.
Research also suggests a connection between asthma and atopy — a predisposition to develop multiple allergies.
Some data suggest
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Doctors diagnose asthma with a physical exam and lung function tests. Two common tests are peak flow and spirometry.
A peak flow test uses a meter to measure your breathing capacity, with results tracked over time. If your peak flow readings are low, asthma may be suspected.
Spirometry measures your breathing differently. It checks how much difficulty you have in exhaling. During this test, you breathe in deeply, then exhale as quickly as you can while the device measures your airflow.
If allergic asthma is suspected, you may also be tested for allergies. Blood tests are typically used for food allergies.
For most other allergies, though, skin testing yields more accurate results. This works by pricking the skin and inserting a small amount of a suspected substance.
After several minutes, your doctor examines your skin for reactions. A positive response appears as a large, red bump.
Asthma remains a significant health problem, especially for children. While people still die from asthma in developing nations, outcomes are usually better in developed countries where resources and early detection are abundant.
After being diagnosed with asthma, your primary goal will be to keep the condition under control and prevent asthma attacks. Although asthma attacks aren’t usually deadly, severe symptoms can lead to hospital stays.