Overview

Asthma is a chronic respiratory condition characterized by inflammation and narrowing of the airways in the lungs, which makes it difficult for a person to breathe properly.

When an individual with asthma is exposed to certain triggers (listed below), the airways become swollen, produce extra mucus, and the muscles around them tighten. This makes it hard for air to flow in and out of your lungs, causing symptoms such as wheezing, coughing, shortness of breath, and chest tightness.

Asthma can range from mild to severe and can be a life-long condition, but it can be managed with proper treatment and lifestyle changes.

Prevalence

According to the World Health Organization (WHO), it’s estimated that over 300 million individuals worldwide have asthma, and the prevalence is increasing in many countries, especially among children.

In the United States, asthma affects approximately 25 million Americans, or 8% of the population. Asthma is more common in women than in men, and it’s more prevalent in urban areas than in rural areas.

Additionally, asthma can have a significant impact on your quality of life, as it can limit physical activity, disrupt sleep, and/or require ongoing medical treatment.

Symptoms

The signs and symptoms of asthma can vary from person to person, and they can also vary in severity and frequency.

Common signs and symptoms include the following:

• Wheezing
• Shortness of breath
• Coughing: A persistent cough, especially at night or early in the morning, which may produce mucus.
• Difficulty breathing
• Rapid breathing: Breathing faster than normal, especially during physical activity or exercise.
• Fatigue: Feeling tired or weak due to difficulty breathing and inadequate oxygen supply.

Not everyone with asthma experience all of these symptoms, and some individuals may even have symptoms that are mild or infrequent.

Some people with asthma may have symptoms that worsen during certain times of the year or in response to certain triggers, such as exposure to allergens or respiratory infections.

• Difficulty breathing
• Swelling of your face, throat, and/or tongue
• Increased heartbeat
• Dizziness and/or fainting
• Confusion and/or disorientation

If you experience any of these symptoms after exposure to an allergen, seek emergency medical care immediately.

Triggers

Asthma triggers are substances or conditions that can cause inflammation and narrowing of the airways in those with asthma, leading to asthma symptoms.

Some common asthma triggers may include the following:

• Allergens: pollen, dust mites, animal dander, and/or mold.
• Irritants: tobacco smoke, air pollution, chemicals, and/or strong odors.
• Respiratory infections
• Exercise
• Weather changes: cold air, humidity, or sudden changes in temperature
• Strong emotions: stress or anxiety.
• Medications:aspirin or non-steroidal anti-inflammatory drugs (NSAIDs) including ibuprofen or naproxen can trigger asthma symptoms.

It's important for those with asthma to identify their triggers and take steps to avoid or minimize exposure to them, as this can help prevent asthma symptoms and reduce the need for medication. Your doctor can work with you to identify your triggers and develop a plan for managing your asthma.

Types of Asthma

There are several types of asthma based on their triggers, symptoms, and underlying causes.

Some of the most common types of asthma include the following:

• Allergic asthma: triggered by exposure to allergens such as pollen, dust mites, or pet dander.
• Non-allergic asthma: triggered by exercise, cold air, stress, or respiratory infections.
• Occupational asthma: caused by exposure to certain substances in the workplace, such as chemicals, dust, or fumes.
• Exercise-induced asthma: triggered by physical activity or exercise.
• Childhood asthma: diagnosed in children and can improve or go away as they age.
• Adult-onset asthma: diagnosed in adults who have never had asthma before.
• Severe asthma: difficult to control and may require higher doses of medication or other treatments.

Diagnosis

Asthma diagnosis usually involves a combination of medical history, physical exam, and lung function tests.

Here are the typical steps taken in an asthma diagnosis:

• Medical history

• Physical exam

• Lung function tests

  The 2 most common tests are spirometry and peak flow measurement.

  • Spirometry measures how much air you can exhale and how quickly.

    FVC (expiratory forced vital capacity): After taking a deep breath, your FVC consists of the maximum volume of air that’s exhaled.

    FEV1 (forced expiratory volume in one second): How much air you can obstructively exhale in 1 second is your FEV1.

  • Peak flow measurement measures how fast you can exhale. A peak flow meter is used to determine the peak expiratory flow rate (PEFR).

    This can be used as an initial diagnostic to screen for variability in expiratory airflow restriction. In other words, this test is used to determine how quickly you can blow air out of your lungs.

    For a period of 2 weeks, you will use the peak flow meter twice daily to monitor your PEFR; if your average daily PEFR fluctuation is more than 10%, this implies an asthma diagnosis.

• Bronchoprovocation tests

  These tests involve inhaling a substance that can trigger asthma symptoms, such as methacholine, and monitoring lung function to see if symptoms develop.

• Allergy testing

  If an allergy is suspected to be a trigger for asthma, allergy testing may be performed to identify specific allergens.

Treatment Options

The treatment of asthma aims to control symptoms, prevent complications, and improve lung function.

Treatment options for asthma may include the following:

Inhaled bronchodilators

These are medications are part of a drug class of medications called beta-2 agonists, that help relax the muscles around your airways, making it easier to breathe.

They can be short-acting, such as albuterol, for quick relief of symptoms or long- acting, such as salmeterol, for use as a maintenance medication.

Some examples include the following:

• Short-acting beta-2 agonists (SABAs): used as needed (rescue therapy) for acute asthma symptoms.
  • Albuterol (ProAir HFA, ProAir RespiClick, Proventil HFA, Ventolin HFA, ProAir Digihaler)
  • Levalbuterol (Xopenex, Xopenex HFA)
  • Epinephrine (Primatene mist)
• Long-acting beta-2 agonists (LABAs)
  • Salmeterol (Serevent Diskus)

Inhaled corticosteroids

These medications reduce inflammation in your airways, which can help prevent asthma symptoms from developing. They are typically used as maintenance medications and may be combined with bronchodilators.

Some examples include the following:

• Beclomethasone (QVAR RediHaler)
• Budesonide (Pulmicort Flexhaler, Pulmicort Respules)
• Ciclesonide (Alvesco)
• Fluticasone (Flovent HFA, Flovent Diskus, Flovent Ellipta)
• Fluticasone + Salmeterol (Advair Diskus, Advair HFA, AirDuo RespiClick, Wixela Inhub)
• Mometasone (Asmanex HFA, Asmanex Twisthaler)

Leukotriene modifiers

These medications can help reduce inflammation in your airways and may be used in conjunction with inhaled corticosteroids.

Some examples include the following:

• Montelukast (Singulair)
• Zafirlukast (Accolate)
• Zileuton (Zyflo, Zyflo CR)

Immunomodulators

These medications, such as omalizumab, are used for individuals with severe asthma that is difficult to control with other medications.

Combination inhalers

These inhalers contain both a bronchodilator and an inhaled corticosteroid, which can provide both quick relief of symptoms and long-term asthma control.

Allergy medications

For those with asthma triggered by allergies, allergy medications such as antihistamines or allergy shots may be helpful.

It's highly recommended for those with asthma to work with their doctor to develop an asthma management plan that includes a treatment plan tailored to your specific needs. Proper treatment can help prevent complications and your improve quality of life.

Complications

Uncontrolled or poorly controlled asthma can lead to a variety of complications, including the following:

• Respiratory infections: Individuals with asthma are at higher risk of developing respiratory infections, such as pneumonia and bronchitis.
• Lung damage: In some cases, repeated asthma attacks can cause irreversible lung damage, leading to chronic respiratory problems.
• Sleep disturbances: Asthma symptoms can worsen at night, leading to sleep disturbances and fatigue.
• Side effects of medications: Some asthma medications can cause side effects, such as jitteriness, tremors, and/or increased heart rate.
• Depression and anxiety: Asthma can cause emotional distress, leading to depression and/or anxiety in some.

Prevention

There is no known way to prevent asthma entirely, as the exact cause of asthma is not yet fully understood. However, there are steps that can be taken to reduce your risk of developing asthma or prevent asthma symptoms from worsening:

• Avoid triggers
• Maintain a healthy lifestyle:
• Manage allergies: Allergy shots or avoiding allergens, can help prevent asthma symptoms.
• Avoid smoking
• Get vaccinated: Getting vaccinated against influenza and pneumonia can help prevent respiratory infections, which can trigger asthma symptoms.
• Follow an asthma management plan